Journals >Chinese Journal of Lasers
Contents
2004
Volume: 31 Issue s1
174 Article(s)
Export citation format
Research Article
Laser Devices and Laser Physics
Radiation from Nanostructured Materials and Example
WANG Shao-min, SHEN Yong-hang, XU Jin-xin, HU Lai-gui, ZHU Jie, YANG De-ren, ZHANG Hui, and YAO Jian-quan
A visible, white and dazzling radiation was observed at room temperature when the nanostructured materials in vacuum were irradiated by many kinds of semiconductor laser diodes (LDs). The photoluminescence from different nano-materials have common property as well as individual characteristics. Some nanostructured semiA visible, white and dazzling radiation was observed at room temperature when the nanostructured materials in vacuum were irradiated by many kinds of semiconductor laser diodes (LDs). The photoluminescence from different nano-materials have common property as well as individual characteristics. Some nanostructured semiconductor can be stimulated to emit an ultraviolet radiation besides visible light A normal InGaAs LD operating at 980 nm is a typical example, which possesses a strong deep UV emission at room temperature..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 1 (2004)
Study on DPL Technology of Hectowatt Green Laser
WANG Wei-min, YAO Zhen-yu, PANG Yu, GAO Qing-song, CHEN Xiao-lin, TONG Li-xin, and ZHANG Lei
Diode laser arrays side-pumped Nd:YAG slab double-pass laser power amplifier is studied in the paper. Experimental results and numerical simulations of laser performance are presented. ΜΟΡΑ system has been built up using gaussian beam as source. Over 210 mJ energy per pulse green laser output at 500 Hz repetition rate Diode laser arrays side-pumped Nd:YAG slab double-pass laser power amplifier is studied in the paper. Experimental results and numerical simulations of laser performance are presented. ΜΟΡΑ system has been built up using gaussian beam as source. Over 210 mJ energy per pulse green laser output at 500 Hz repetition rate is achieved Beam quality M2 is less than 6.5.The fluctuation of the laser output energy is less than 2%. The result shows that the experimental data have been consistent with the numerical calculation results..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 5 (2004)
LD Pumped Nd:YAG Laser with Output Power of 300 W
JIANG Dong-sheng, ZHAO Hong, WANG Jian-jun, and ZHOU Shou-huan
The careful theoretical and experimental study was performed on the relationship between laser output power and beam quality for the cw laser diode pumped Nd:YAG rod laser. In the condition of LD side pumping, the pumping uniform and the absorption efficiency to pumping light was compensated by optimizing the laser resThe careful theoretical and experimental study was performed on the relationship between laser output power and beam quality for the cw laser diode pumped Nd:YAG rod laser. In the condition of LD side pumping, the pumping uniform and the absorption efficiency to pumping light was compensated by optimizing the laser resonator with dual rod structure. The thermal induced birefringence was compensated by inserting polarization rotator and optical image system between two rods. The average laser output power of 300W with 25% light-light conversion efficiency was obtained when the total pumping power was 1200 W. The Q-switched laser beam at repetition rate of 15 kHz with average output power of 240 W, beam quality Af of 18 and pulse width of 110 ns was obtained too..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 8 (2004)
Relativistic Modification of the Measurement of Electron Temperature in HL-1M Tokamak by Laser Scattering
FENG Jie, HUANG Yuan, SHI Pei-lan, and DENG Zhong-chao
This article briefly describs the measurement of electron temperature in HL-1M Tokamak plasma and the way of relativistic modification due to blue shift in the case of higher electron temperature. A simple formula to calculate electron temperature is given under the condition that relativistic modification is taken intThis article briefly describs the measurement of electron temperature in HL-1M Tokamak plasma and the way of relativistic modification due to blue shift in the case of higher electron temperature. A simple formula to calculate electron temperature is given under the condition that relativistic modification is taken into account on HL-1M Tokamak The blueshift is approximately proportional to the electron temperature. When electron temperature is hundreds of eV’ the blueshift is small, when electron temperature is thousands of eV, the blueshift is great The error of electron temperature is proportional to electron temperature to the forth power. When electron temperature is higher than 1 keV, the error is great than that of not taking into account relativistic effect, it is about 100-200 eV. When electron temperature is below 1 keV, the error is smaller than that of not taking into account relativistic effect, it is about 5-60 eV..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 11 (2004)
Broadly Tuning BBO Optical Parametric Oscillator in the Visible and Infrared range without Changing Optical Components
YAO Bao-quan, WANG Yue-zhu, and WANG Qi
To realize broad tunable range in 0.4-2.0 μm of BBO ΟΡΟ without changing optical components, two kinds of cavity configurations such as double right-angle prisms ring cavity and linear cavity pumped from side direction with two walk-off compensating crystals were used. Although the longer resonator and high intracavityTo realize broad tunable range in 0.4-2.0 μm of BBO ΟΡΟ without changing optical components, two kinds of cavity configurations such as double right-angle prisms ring cavity and linear cavity pumped from side direction with two walk-off compensating crystals were used. Although the longer resonator and high intracavity loss lead to higher threshold, both the configurations can ensure the broad tunable output with the range of 0.43-0.65 μm for signal and 0.78-2.01 μm for idler without changing mirrors or crystals..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 14 (2004)
Energy Pooling Collisions for Rb(5P)+Cs(5D) in a Rb-Cs Mixture
SHEN Yi-fan, and DAI Kang
The rate coefficient for energy-pooling collision Rb(5P)+Cs(5D)→Rb(5S)+Cs(8D) in the Rb-Cs vapor mixture has been measured using a known energy-pooling rate coefficient of a homonuclear reaction [ie.,Cs(6P)+Cs(5D)→Cs(6S)+Cs(7D J)]. Populations of the Cs(6P,5D) arid Rb(5P) states have been produced by photodissociation The rate coefficient for energy-pooling collision Rb(5P)+Cs(5D)→Rb(5S)+Cs(8D) in the Rb-Cs vapor mixture has been measured using a known energy-pooling rate coefficient of a homonuclear reaction [ie.,Cs(6P)+Cs(5D)→Cs(6S)+Cs(7D J)]. Populations of the Cs(6P,5D) arid Rb(5P) states have been produced by photodissociation of Rbj and 0? molecules by the use of a dye laser radiation. The resulting fluorescence includs the components emitted in the decay of the exited states produced by photodissociation and the components arised from the collisionally populated excitation-states. By combining relative intensities of the components with Cs(6P), Rb(5P) states effective lifetimes, the rate coefficient for the heteronuclear energy-pooling is obtained to be cm3/s. The contribution to the rate coefficient from other processes is discussed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 17 (2004)
On Quantum Optics and Quantum Information Questions in Tavis-Cummings Model
XIA Yun-jie, ZUO Zhan-chim, and ZHAO Jia-qiang
In this paper, the time evolution of Tavis-Cummings model and the non-classical properties of field are studied The function of second order coherence is accurately evaluated and the relation between second order coherence function and atomics coupling is discussed The quantum entanglement produced in this system is stIn this paper, the time evolution of Tavis-Cummings model and the non-classical properties of field are studied The function of second order coherence is accurately evaluated and the relation between second order coherence function and atomics coupling is discussed The quantum entanglement produced in this system is studied in detail. The three-qubit entangled state can be obtained under the proper initial state. Using the Coffinan definition of three-paiticle entanglement, the entanglement measure of three-qubit is discussed in this system. The system will evolve into W-entangled state for some initiai conditions and the necessary condition for W-entangled state is given. The 3-tangle of the system will change with the system initial state, coupling coefficients between the two atoms and field or atoms..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 20 (2004)
Linear Optical Elements and Generation of Quantum Entanglement
SONG Peng, and XIA Yun-jie
The application of even and odd coherent states in quantum information is studied. We generate a kind of entanglement with beam splitter by inputting even and odd coherent states into lossless beam splitter. We relate the density operators at the input and output ports of the beam splitter by means of the angular-momenThe application of even and odd coherent states in quantum information is studied. We generate a kind of entanglement with beam splitter by inputting even and odd coherent states into lossless beam splitter. We relate the density operators at the input and output ports of the beam splitter by means of the angular-momentuni transformation and the connection between it's unitary matrix representation and three-dimensional angular-momentum group. Then we get the joint output photo-number distribution. When the vacuum state is injected into one input port while even or οdd coherent state is injected into the other, quantum entanglement is generated at the output ports. Even and odd coherent states have the opposite output quantum entanglement properties in this case. When arbitrary even or οdd coherent states are injected into both of separate input ports, there will be more complicated quantum entanglement at both of output ports..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 23 (2004)
Theory of Quasi-State Modes of Random Lasers
LIU Jing-song, WANG Chun, WANG Ke-jia, WANG Hong, and LV Jian-tao
The dynamical evolution of the localized states of optical beams is investigated by use of the quasi-state modestheory of random lasers in one-dinmension random meida with four-level atomic system Results show that the larger thepump rate, the shorter the formation time of the localized states.The dynamical evolution of the localized states of optical beams is investigated by use of the quasi-state modestheory of random lasers in one-dinmension random meida with four-level atomic system Results show that the larger thepump rate, the shorter the formation time of the localized states..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 26 (2004)
Influences of Linewidth Enhancement Factor of Semiconductor Laser on Self-Mixing Signal
LV Liang, GUI Hua-qiao, XIE Jian-ping, ZHAO Tian-peng, and MING Hai
This paper presents a theoretical analysis on self-mixing interference by using a three-mirror model. The laser self-mixing signal with different values of the linewidth enhancement factor α is obtained by numerical solution Results indicate that adopt semiconductor laser with big values of a can enhance SNR of self-miThis paper presents a theoretical analysis on self-mixing interference by using a three-mirror model. The laser self-mixing signal with different values of the linewidth enhancement factor α is obtained by numerical solution Results indicate that adopt semiconductor laser with big values of a can enhance SNR of self-mixing signal and in favor of direction discrimination..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 29 (2004)
Experimental Study of Tm,Ho:YLF Laser Cooled by Liquid N2
YAO Bao-quan, WANG Yue-zhu, DONG Li-qiang, and LI Yu-feng
Tm (6%), Ho (0.5%):YLF laser cooled by liquid nitrogen pumped by a laser diode with 792 nm wavelength was studied in theory and experiment The maximum 350 mW output power was obtained, and optical-optical conversion efficiency is 20% corresponding to 28% slope efficiency. The threshold power and output power dependenceTm (6%), Ho (0.5%):YLF laser cooled by liquid nitrogen pumped by a laser diode with 792 nm wavelength was studied in theory and experiment The maximum 350 mW output power was obtained, and optical-optical conversion efficiency is 20% corresponding to 28% slope efficiency. The threshold power and output power dependence on the temperature of Tm,Ho:YLF crystal and the wavelength of LD were also studied..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 32 (2004)
Edge-Pumped Thin-Disc Nd:YAG Lasers
LIU Qiang, GONG Ma-U, YAN Ping, and JU Li-yang
The thin-disc lasers design based on conduction cooling and a novel pumping geometry called edge pumping was developed The edge pumping geometry separated the cooling and optical pumping interfaces, resolves prior difficulties with high average power pumping and the rejection of amplified spontaneous emission (ASE), siThe thin-disc lasers design based on conduction cooling and a novel pumping geometry called edge pumping was developed The edge pumping geometry separated the cooling and optical pumping interfaces, resolves prior difficulties with high average power pumping and the rejection of amplified spontaneous emission (ASE), simplifying the laser head desiga The 5 W output power with sloppy efficiency 11.9% from 1at.-% Nd:YAG using edge pumping six corners disc was obtained The pump light distributing and absorbing in the disc are analyzed using tray trace, problem for edge pumping disc laser are indicated..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 35 (2004)
High Power Nd:YAG Thin Disk Laser Pumped by 2D-Stacks Diode Array
TANG Chun, TU Bo, JIANG Jian-feng, GAO Song-xin, GAO Qing-song, YAO Zhen-yu, and WU De-yong
The principle of high-brightness and high-average-power thin-disk laser is introduced and the design principle is put forward. The experiment is carried out with Nd:YAG of 1 mm thickness and 1.4% Nd doping pumped by home-made CW 1 kW 2D-stacks diode array. The pump gain area is 5 mm×7 mm. The peak output power of The principle of high-brightness and high-average-power thin-disk laser is introduced and the design principle is put forward. The experiment is carried out with Nd:YAG of 1 mm thickness and 1.4% Nd doping pumped by home-made CW 1 kW 2D-stacks diode array. The pump gain area is 5 mm×7 mm. The peak output power of 397 W is achieved with 39.3% optical to optical efficiency at 20% duty cycle Q-CW running mode..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 38 (2004)
Frequency Tunable LD Pumped Non-Planar Ring Cavity Single Frequency Nd:YAG Laser
YANG Su-hui, SUN Wen-feng, LI Zhuo, ZHAO Chang-ming, and WEI Guang-hui
A non-planar unidirectional ring laser cavity with a corner cube prism and a specially cut Nd:YAG crystal is reported in this paper. 230 mW single frequency output power was obtained from the laser cavity at pumping power of 1 W. Slope efficiency is 51%. By changing the length of the laser cavity with a piezoelectric cA non-planar unidirectional ring laser cavity with a corner cube prism and a specially cut Nd:YAG crystal is reported in this paper. 230 mW single frequency output power was obtained from the laser cavity at pumping power of 1 W. Slope efficiency is 51%. By changing the length of the laser cavity with a piezoelectric ceramic, 560 MHz frequency modulation rang was observed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 41 (2004)
Study of LD End-Pumped Yb:YAG Solid State Laser
LI Lei, YANG Su-hui, SUN Wen-feng, and ZHAO Chang-ming
The parameters of LD end-pumped Yb:YAG solid state laser were calculated, when the pump light waist were assumed to be 400 μm or 160 μm, the laser waist was 130 μm, and Yb:YAG crystal was 8 at-% doped The calculation was testified perfectly in experiment.The parameters of LD end-pumped Yb:YAG solid state laser were calculated, when the pump light waist were assumed to be 400 μm or 160 μm, the laser waist was 130 μm, and Yb:YAG crystal was 8 at-% doped The calculation was testified perfectly in experiment..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 43 (2004)
Theoretical Study on Temperature Distribution Characteristics in Working Medium Side-Pumped by Diode Bars
ZHAO Hong, JIANG Dong-sheng, ZHOU Shou-huan, WANG Jian-jun, ZHANG Da-yong, and ZHAO Shu-yun
Temperature distribution characteristics in working medium side-pumped by diode bars are completely theoretical studied Intra-relationship between gain distribution and temperature distribution is analyzed. With computer, temperature distribution characteristics in different conditions are theorial calculated and discuTemperature distribution characteristics in working medium side-pumped by diode bars are completely theoretical studied Intra-relationship between gain distribution and temperature distribution is analyzed. With computer, temperature distribution characteristics in different conditions are theorial calculated and discussed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 46 (2004)
Study on LD End-Pumped and Passively Q-Switched Miniature Laser with High Repetition
ZHANG Da-yong, ZHAO Hong, JIANG Dong-sheng, WANG Jian-jun, ZHAO Shu-yun, YANG Tao, and ZHOU Shou-huan
The principle of LD end-pumped and passively Q-switched Nd:YAG/Cr4+:YAG laser is introduced in the paper, the result of relative simulation and experiment is also presented The stable single longitude mode laser pulse with energy of 33 μJ and FWHM of 3.9 ns with 2 kHz high repetition is acquired.The principle of LD end-pumped and passively Q-switched Nd:YAG/Cr4+:YAG laser is introduced in the paper, the result of relative simulation and experiment is also presented The stable single longitude mode laser pulse with energy of 33 μJ and FWHM of 3.9 ns with 2 kHz high repetition is acquired..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 49 (2004)
Diode Pumped YAG Lasers Amplifier Research
SUN Wei-na, WANG Wei-li, ZHU Chen, WANG Zhi-tong, YANG Wen-shi, and WANG Xiao-han
A diode-pump ΜΟΡΑ system with high beam quality and high peak power is introduced in this article. The amplification character of the laser is studied By optimizing the pumping structure and using the image transmission and phase conjugation technology, the laser output reaches 400mJ per pulse at a typical repetition rA diode-pump ΜΟΡΑ system with high beam quality and high peak power is introduced in this article. The amplification character of the laser is studied By optimizing the pumping structure and using the image transmission and phase conjugation technology, the laser output reaches 400mJ per pulse at a typical repetition rate of 40 Hz, and pulse width is 7 ns, beam quality is better than 2 times diffraction limit..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 52 (2004)
High Power Diode-Pumped Nd:YAG 1.319 μm TEM00 Laser
SUN Xiao-jie, YU Ying-pu, and PEI Bo
A diode-pumped Nd:YAG 1.319 μm ΤΕΜ00 laser with high power is presented. Through optimizing the stable resonator and inserting a diaphragm to get large fundamental mode volume and reduce the rod thermal lensing, when pumping power is 343 W, an output of 6 W TEM00 1.319 μm laser with an optical-to-optical efficiency of A diode-pumped Nd:YAG 1.319 μm ΤΕΜ00 laser with high power is presented. Through optimizing the stable resonator and inserting a diaphragm to get large fundamental mode volume and reduce the rod thermal lensing, when pumping power is 343 W, an output of 6 W TEM00 1.319 μm laser with an optical-to-optical efficiency of 1.74% and beam quality M2<2 has been demonstrated..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 55 (2004)
Green and Blue Laser Emission Based on Nd:GdAl3(BO3)4 Crystal Pumped by Ti:sapphire Laser
CHEN Yu-jin, HUANG Miao-liang, LUO Zun-du, HUANG Zhi-yun, and HUANG Yi-dong
Pumped by a Ti:sapphire laser, a continuous wave blue laser emission was generated in a non-linear laser crystal Nd:GdAla(B03)4 (NGAB) by self-sum-frequency-mixing (SSFM) between the pumping and the fundamental lasers. Based on the SSFM, simultaneously CW green and blue laser emission were achieved by insert a non-linePumped by a Ti:sapphire laser, a continuous wave blue laser emission was generated in a non-linear laser crystal Nd:GdAla(B03)4 (NGAB) by self-sum-frequency-mixing (SSFM) between the pumping and the fundamental lasers. Based on the SSFM, simultaneously CW green and blue laser emission were achieved by insert a non-linear optical crystal KTP between the NGAB crystal and the output mirror of the cavity..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 58 (2004)
Study on a Gain-Switched Nd3+:YVO4 Microchip Laser
SHENG Fang, Ы Dong-ming, and CHEN Jun
Using gain-switching technique in the N<f*:YVO4 microchip laser pumped by the laser diode (LD), steady single mode laser pulse-trains with pulse-width of 60-140 ns and repetition rate of 1 kHz are obtained. The LD is driven by a repetitive modulating pulse current added on a DC bias. The repetition rate of laser outUsing gain-switching technique in the N
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 61 (2004)
High Efficiency Ring Resonator 1.57 μm OPO Laser
BAO zhao-ri-ge-tu, ZHAO Hai-xia, and ZHOU Shou-huan
By using ring resonator of noncritical phase matching of KTP crystal, the output energy of 20 mJ in 1.57 μm eye safe laser is obtained. The conversion efficiency is 58%, the laser has the properties of compaction,simplicity easy engineering. This is propitious to extend aplication in the field of laser ranging and laseBy using ring resonator of noncritical phase matching of KTP crystal, the output energy of 20 mJ in 1.57 μm eye safe laser is obtained. The conversion efficiency is 58%, the laser has the properties of compaction,simplicity easy engineering. This is propitious to extend aplication in the field of laser ranging and laser radar..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 64 (2004)
1319 nm and 1338 nm Nd:YAG Laser with Single Spectral Line
SHEN Hong-yuan, ZENG Rui-rong, ZHANG Ge, HUANG Cheng-hui, and WEI Min
1319 nm or 1338 nm laser can be generated by secondary transition of Nd3+ ion from 4F3/2-4I13/2 in YAG crystal. The stimulated emission cross sections of both spectral lines approach to each other, and are 1/5 of that of 1064 nm primary transition. In order to achieve laser of single spectral line in secondary transiti1319 nm or 1338 nm laser can be generated by secondary transition of Nd3+ ion from 4F3/2-4I13/2 in YAG crystal. The stimulated emission cross sections of both spectral lines approach to each other, and are 1/5 of that of 1064 nm primary transition. In order to achieve laser of single spectral line in secondary transition with high efficiency, three-chromatic mirror technology is used to restrain spectral lines of primary transition and other transition in secondary transition,and then several lasers of single spectral line in secondary transition have developed: 1) LD pumped 1319 nm or 1338 nm TEMo, mode Nd:YAG CW laser. Output power 200 mW, efficiency 20%; 2) Kr lamp pumped 1319 nm TEM00, mode Nd:YAG CW laser. Output power 6 W, efficiency 0.12%; 3) Kr lamp pumped 1319 nm high power Nd:YAG CW laser. Output power 100 W, efficiency 1.67%.
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 66 (2004)
Theoretic Study of Intracavity Frequency Doubling Red and Green Dual-Wavelength Laser
ZHANG Ge, SHEN Hong-yuan, HUANG Cheng-hui, HUANG Ling-xiong, WEI Yong, WEI Min, and ZENG Rui-rong
The four level rate equations of intracavity frequency doubling of 1079.5 nm and 1341.4 nm dual-wavelength Nd:YAlO3 laser are built and solved numerically. The results show that the continual wave (CW) dual-wavelength frequency doubled laser can be realized and CW red and green lasers can be achieved simultaneously. TwThe four level rate equations of intracavity frequency doubling of 1079.5 nm and 1341.4 nm dual-wavelength Nd:YAlO3 laser are built and solved numerically. The results show that the continual wave (CW) dual-wavelength frequency doubled laser can be realized and CW red and green lasers can be achieved simultaneously. Two methods for achieving the balanced output of red and green lasers are compared The method through changing the geometry factor to get the balanced output of red and green lasers is more effective than that through the adding of the additional loss..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 69 (2004)
The Research on Dual-Wavelength Laser System with a Voltage Controlled Q-Switch Structure in the Cavity
CHEN Chang-shui, WU В?аn, WANG Jin, GONG Chuan-bo, ZHU Ling, SONG Qiu-ming, and XIE Jian-ping
A flashlamp-pumped CrLiSAF laser system with a voltage controlled Q-switch structure in the cavity has been designed. The relation of laser output behaviors with input energy is studied experimentally. The pulse width of 30 ns and the pulse energy of 30 mJ had been gained The two pulses gained by a voltage controlled QA flashlamp-pumped CrLiSAF laser system with a voltage controlled Q-switch structure in the cavity has been designed. The relation of laser output behaviors with input energy is studied experimentally. The pulse width of 30 ns and the pulse energy of 30 mJ had been gained The two pulses gained by a voltage controlled Q-switch structure in the cavity was very important in different lidar sysytems..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 73 (2004)
Experiment on High Power Laser Diode Linear Arrays Coupling with Optic Fiber
WU De-yong, GAO Song-xin, LV Wen-qiang, and WEI Bin
The optic characters of high power laser diode linear arrays are analyzed, and a device is designed to reshape its laser beam, the emission of a 10 mm width continued wave laser diode linear arrays can be coupled into a fiber by the device. The laser beam of laser diode is collimated in fast direction by a cylindrical The optic characters of high power laser diode linear arrays are analyzed, and a device is designed to reshape its laser beam, the emission of a 10 mm width continued wave laser diode linear arrays can be coupled into a fiber by the device. The laser beam of laser diode is collimated in fast direction by a cylindrical micro lens, then a pair of step-mirrors symmetries the beam parameter products in fast direction and slow direction, and a focusing lens couples the light into an optical fiber. Experiment is carried out, the emission of a laser diode linear array with 42 W laser power was coupled into a fiber witii the core diameter of lmm and numerical aperture of 0.38. The output power of 25 W from the fiber is obtained with the coupling efficiency of 59.5%..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 76 (2004)
Recent Progress of Photonic Crystal Lasers
XU Gui-wen, OUYANG Zheng-biao, RUAN Shuang-chen, and LI Jing-zhen
Recent progress of photonic crystal lasers is reviewed. The structures, operating principles and features, and the fabrication methods of various kinds of photonic crystal lasers are reviewed. A preview of the future development of the photonic crystal lasers is presented.Recent progress of photonic crystal lasers is reviewed. The structures, operating principles and features, and the fabrication methods of various kinds of photonic crystal lasers are reviewed. A preview of the future development of the photonic crystal lasers is presented..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 79 (2004)
New High Efficiency Eye-Safe OPO Solid State Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Adjust-free resonator is applied in the Cr4+:YAG passive Q switched ΟΡΟ laser. Overall performance of laser is much better than that in plane-parallel resonator the wall-plug efficiency rises from 2.2%o to 2.7%o, the 1.57 μm pulse energy rises from 18 mJ to 21.4 mJ, the pulse width decreases from 24 ns to 7.8 ns, the bAdjust-free resonator is applied in the Cr4+:YAG passive Q switched ΟΡΟ laser. Overall performance of laser is much better than that in plane-parallel resonator the wall-plug efficiency rises from 2.2%o to 2.7%o, the 1.57 μm pulse energy rises from 18 mJ to 21.4 mJ, the pulse width decreases from 24 ns to 7.8 ns, the beam divergence decreases from 8 mrad to 7 mrad. Also, the stability of the directional prism resonator's output pulse energy, beam direction, pulse width and wave sh叩e are much better than that of the plane parallel resonator's. After optimization, a smart ΟΡΟ laser with small, nigh efficiency, high stability and high beam quality is obtained..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 82 (2004)
Study on Rate Equation of Microchip Laser
HUANG Zhi-yun, HUANG Miao-liang, LUO Zun-du, GONG Xing-hong, and HUANG Yi-dong
A rate equation of the microchip laser based on a quasi-three level system is proposed, which has taken the fluorescence concentration quenching and the Boltzmann distribution resulted from thermal effect into account This rate equation is applied to Yb3+:YAl3(BO3)4 microchip laser, and the comparison of the calculatedA rate equation of the microchip laser based on a quasi-three level system is proposed, which has taken the fluorescence concentration quenching and the Boltzmann distribution resulted from thermal effect into account This rate equation is applied to Yb3+:YAl3(BO3)4 microchip laser, and the comparison of the calculated and experimental results shows that this equation is valid to a certain extent Finally, some schemes about the optimization of the Yb3* concentration and the crystal thickness of the Yb3+:YAl3(BO3)4 microchip laser are given..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 85 (2004)
Design and Analysis of Shot Pulse Z-Fold RF Waveguide CO2 Laser with Common Electrode
TIAN Zhao-shuo, WANG Peng-hua, MU Jin-long, and WANG Qi
Design of electro-optically cavity-dumped Z-fold RF waveguide CO2 laser with common electrode is presented The structures of Z-fold and cavity dump are used for the transmitter laser to improve laser output power greatly at the condition of limited size. The construction of single channel is used for the local laser. TDesign of electro-optically cavity-dumped Z-fold RF waveguide CO2 laser with common electrode is presented The structures of Z-fold and cavity dump are used for the transmitter laser to improve laser output power greatly at the condition of limited size. The construction of single channel is used for the local laser. The two channels are excited by the same RF source This kind of structure is helpful for improving the heterodyne frequency stabilization. In addition, the control method for the laser waveform of cavity dumps is analyzed in theory..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 87 (2004)
External Frequency Doubling Study of Yb3+ Doped Pulse Fiber Laser
LIN Hao-jia, YAN Pei-guang, DU Chen-lin, RUAN Shuang-chen, ZHOU Chao-ming, REN Ning, and LV Ke-cheng
An efficient green laser through the direct external frequency doubling of a 1064 nm Yb3+ doped pulse fiber laser by the use of a KTP crystal was developed The maximum average green power is 1.78 W at the average Ш input power of 10 W, resulting in the conversion efficiency of 17.8%.An efficient green laser through the direct external frequency doubling of a 1064 nm Yb3+ doped pulse fiber laser by the use of a KTP crystal was developed The maximum average green power is 1.78 W at the average Ш input power of 10 W, resulting in the conversion efficiency of 17.8%..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 90 (2004)
Investigation on Transient Gain Characteristics of Yb-doped Double Clad Fiber Amplifier
KONG Ling-feng, LOU Qi-hong, ZHOU Jun, WU Zhong-lin, DONG Jing-xing, WEI Yun-rong, and ZHU Jian-qiang
A reduced model for transient gain is proposed and low repetition rate pulse after YDCFA is investigated through numerical calculation· Transient gain saturation and recovery is also discussed theoretically. Pulse amplified characteristics at different pump power and repetition rate are obtained through experimentA reduced model for transient gain is proposed and low repetition rate pulse after YDCFA is investigated through numerical calculation· Transient gain saturation and recovery is also discussed theoretically. Pulse amplified characteristics at different pump power and repetition rate are obtained through experiment, which is well in agreement with theoretical analysis..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 93 (2004)
Spectrum Emitted by Laser-Induced Plasma:Influence of the Spatial Inhomogeneity of the Plasma
LIN U-yun, WANG Sheng-bo, GUO Da-hao, WU Hong-xing, XIA Xiao-ping, DAI Yu-sheng, LI Guo-jie, and LI Jing
Some results of the laser induced plasma spectra in the visible range are presented. It is noticed that the spatial shape and fluorescent color of the induced plasma are different for different target materials, and the induced plasma beam is perpendicular to the target despite whether the laser is oblique to the targeSome results of the laser induced plasma spectra in the visible range are presented. It is noticed that the spatial shape and fluorescent color of the induced plasma are different for different target materials, and the induced plasma beam is perpendicular to the target despite whether the laser is oblique to the target The optimum location in the plasma for spectral analysis is different for various targets which depends on the atomic mass. And a characteristic spectrum of the ArI (578.352 nm) is discovered in the plasma spectra of red copper and the Fe doped with Zn, while ArI (578.155 nm) is discovered in the plasma spectra of brass..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 96 (2004)
Effects of Purity and Pressure on 309nm Spectrum of Argon Excited by Electron Beam
ZHAO Yong-peng, WANG Qi, WU Yin-chu, and LIU Jin-cheng
The relativistic electron beam is used to excite argon and the effects of purity and pressure on 309 nm spectrum are studied. The experimental results of purity show that the intensity of 309 nm spectrum decreases with the increase of purity. These results are inconsistent with that the 309 nm spectrum would originate The relativistic electron beam is used to excite argon and the effects of purity and pressure on 309 nm spectrum are studied. The experimental results of purity show that the intensity of 309 nm spectrum decreases with the increase of purity. These results are inconsistent with that the 309 nm spectrum would originate from the transition of H2O. When the pressure of argon is changed, there is a maximum of intensity at 0.08 MPa, and the intensity is almost changeless between 0.1 MPa and 0.2 MPa Thus, the 309 nm spectrum does not originate from the transition of excimer or ionic excimer, which is mainly formed by three body collision..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 99 (2004)
Study on Capillary Plasma Z-Pinch Evolution Based on Snow-Plow
CHENG Yuan-li, LI Si-ning, and WANG Qi
The origin parameters for Ne-like Ar 46.9 nm, Ne-like Kr and Ni-like Xe laser by capillary discharge are estimated The impedance characteristic of capillary for different lengths of gas column is investigated both in theory and experiments. Based on “snow-plow" model, the Ζ-pinch evolution in сapillаrу discharge iThe origin parameters for Ne-like Ar 46.9 nm, Ne-like Kr and Ni-like Xe laser by capillary discharge are estimated The impedance characteristic of capillary for different lengths of gas column is investigated both in theory and experiments. Based on “snow-plow" model, the Ζ-pinch evolution in сapillаrу discharge is presented. Calculated and measured results of pinch time are compared..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 103 (2004)
Enhancement of Stimulated Raman Scattering of Weak-Gain Raman Modes in Circular Cavity
YANG Rui, WANG Ya-li, CHEN Tian-jiang, JIANG Nan, and PU Xiao-yun
The enhancement of stimulated Raman scattering (SRS) of week-gain Raman modes is demonstrated in pendant drops by overlapping the Stokes of the Raman modes with Rhodamine 640 dye gain profile. After obtaining the optimal dye concentration and the pumping intensity, the technique is used to investigate the minority specThe enhancement of stimulated Raman scattering (SRS) of week-gain Raman modes is demonstrated in pendant drops by overlapping the Stokes of the Raman modes with Rhodamine 640 dye gain profile. After obtaining the optimal dye concentration and the pumping intensity, the technique is used to investigate the minority species in binary mixture pendant drops. The limit of detectable concentration for the minority species, methanol in methanol-ethanol and ethanol in ethanol-water mixtures, is greatly reduced..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 107 (2004)
Infrared Grating Monochromator Calibration of Microcomputer Control
QU Yan-chen, REN De-ming, HU Xiao-yong, LIU Feng-mei, ZHOU Bo, JIANG Yong-liang, CHEN Chun-yu, and SONG Wen-mei
Applying grating diffraction equation, multilevel diffractive characteristic of calibration lines of standard optical source was analyzed. Computer simulative calculation was completed on multilevel diffraction of standard optical source to solve intensity distribution of multilevel diffraction. Multilevel diffraction Applying grating diffraction equation, multilevel diffractive characteristic of calibration lines of standard optical source was analyzed. Computer simulative calculation was completed on multilevel diffraction of standard optical source to solve intensity distribution of multilevel diffraction. Multilevel diffraction spectrum distribution of Hg lamp and He-Ne laser were measured, and the order of spectrum was defined. Fit curve was obtained by data processing and polynomial fitting. Infrared grating monochromator calibration was validated to be correct by measuring wavelength of a continuum wave CO2 laser and monitoring its wavelength to use a spectrum analysis instrument synchronously..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 110 (2004)
Harmonic Oscillator Mathematical Modeling of TEA CO2 Laser
QU Уаn-chen, REN De-ming, HU Xiao-yong, LIU Feng-mei, ZHANG Li-li, JIANG Yong-liang, SONG Bao-an, and SONG Wen-mei
Harmonic oscillator mathematical model is a description of TEA CO2 laser vibrational dynamics, and it simplifies temperature model The equations are built using four characteristic variables for three vibration states of CO2 molecule and one of N2 molecule to show energy variety, to relate time to output intensity in cHarmonic oscillator mathematical model is a description of TEA CO2 laser vibrational dynamics, and it simplifies temperature model The equations are built using four characteristic variables for three vibration states of CO2 molecule and one of N2 molecule to show energy variety, to relate time to output intensity in cavity, light flux and gas temperature. The laser pulse waveform can be calculated with varied laser's parameters. The output power and energy can be obtained with intensity, it provides theoretical basis for laser design. Theoretical calculations shows a good agreement with the experimental result..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 113 (2004)
Kinetic Analysis of Electrooptical Q-switched CO2 Pulse Laser
WANG Qi, LU Wei, SHANG Tie-liang, and TIAN Zhao-shuo
On the basis of the previous achievement of research on lasers in our lab the kinetic calculation of Q-switched CO2 pulse laser was completed using the CO2 laser six-temperature modeL In the calculation, the peak power of Q-switched optical pulse was obtained, the variation curves of peak generation time and pulse widtOn the basis of the previous achievement of research on lasers in our lab the kinetic calculation of Q-switched CO2 pulse laser was completed using the CO2 laser six-temperature modeL In the calculation, the peak power of Q-switched optical pulse was obtained, the variation curves of peak generation time and pulse width vs ambient temperatures were estaoushed, and the different curves of these variables vs increasing laser frequency were worked out, which affords the grounds in theory for solving the problem caused by the working using electrooptical Q-switched CO2 pulse laser in outfield..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 116 (2004)
Experimental Investigation of Dark Resonances in Selective Reflection Spectroscopy of Cs Atoms
ZHAO Yan-ting, ZHAO Jian-ming, HUANG Tao, XIAO Lian-tuan, and JIA Suo-tang
Electromagnetically induced transparency (ΕΓΓ) and coherent population trapping (CPT) have received considerable attention in recent years. In this paper, dark resonances in selective reflection spectroscopy of A-type Cs atoms are reported. The temperature of Cs was heated about 150 ℃ and the coupling beam was tuned toElectromagnetically induced transparency (ΕΓΓ) and coherent population trapping (CPT) have received considerable attention in recent years. In this paper, dark resonances in selective reflection spectroscopy of A-type Cs atoms are reported. The temperature of Cs was heated about 150 ℃ and the coupling beam was tuned to the resonant frequency of the transition 6S1/2(F=4)→6P3/2(F=3) and the probe beam frequency was scanned over the transition 6S1/2(F=3)→6P3/2. The frequency detuning and intensity effect of coupling laser were demonstrated in dark resonances spectrum. The obvious induced transparency was observed in the selective reflection spectrum with sub-Doppler structure. The result was important to study the atomic coherent, atom-wall collision, long-range interactions between excited atoms and solid-state surfaces..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 119 (2004)
A Temperature Control Unit for Intracavity SHG
SONG Ting-ting, ZHU Xiao, QI Li-jun, YANG Yun-feng, and QIU Fu-sheng
In high average power lasers, local heating of frequency doubling crystals induced by the residual absorption at the interacting frequencies leads to the destruction of the perfect phase matching condition, which drastically reduces the conversion efficiencies to the second-harmonic generation. In order to obtain high In high average power lasers, local heating of frequency doubling crystals induced by the residual absorption at the interacting frequencies leads to the destruction of the perfect phase matching condition, which drastically reduces the conversion efficiencies to the second-harmonic generation. In order to obtain high efficiency SHG output, a temperature control system is developed using a semiconductor cooler to acljust the temperature and a temperature sensor AD590 as the temperature measurement component The temperature accuracy is 0.1 ℃..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 122 (2004)
A Single Pulse Picosecond Nd:YAG Frequency-Doubled Laser
GAO Hong-wen, SUN Chuan-dong, CHEN Zhi, WANG Guo-zhi, and FENG Shan
A single pulse picosecond Nd:YAG frequency-doubled laser is made up of a resonator, single pulse-selector, amplifier, double frequency crystal, light beam expander and collimator and so on. In order to generate a series of mode-locked pulse laser lights, a passive mode-locked dye cell is used in the resonator. A singleA single pulse picosecond Nd:YAG frequency-doubled laser is made up of a resonator, single pulse-selector, amplifier, double frequency crystal, light beam expander and collimator and so on. In order to generate a series of mode-locked pulse laser lights, a passive mode-locked dye cell is used in the resonator. A single pulse laser light is obtained from the series of mode-locked pulse laser lights after they have passed the single pulse-selector. Finally, output of a laser light beam with energy of 120 mJ and wavelength of 532 nm is realized after the single pulse laser light is amplified and doublea in frequency. Because a laser light drift controller, which is researched and developed by ourselves, is usea in the resonator of the laser, a out-triggering synchro-precision of better than 2 μs is obtained from the laser..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 125 (2004)
An Usable CuBr Laser for Wise Laser Large Screen Displayer
LIU Cai-ming, CHEN Hong-shan, and CHEN Shui-qiao
A kind of discharge tube and calefaction device were designed By using a single stage magnetic pulse compressor in pulse discharge power supply of laser, the power of the CuBr laser has increased by two times as compared with that of then the previous prototype. Average power of 8 W and an efficiency of 1% are obtainedA kind of discharge tube and calefaction device were designed By using a single stage magnetic pulse compressor in pulse discharge power supply of laser, the power of the CuBr laser has increased by two times as compared with that of then the previous prototype. Average power of 8 W and an efficiency of 1% are obtained..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 128 (2004)
Experimental Study on MOPA System of Four-Pass Configuration with Optical Fiber Phase-Conjugator
LI Dong-ming, ZHOU Tao, CHEN Jun, TANG Chun, GAO Qing-song, PANG Yu, TONG Li-xing, and ZHUO You-fu
Using optical nber with diameter of 0100 mm and ￠200 mm as phase-coryugator, the energy reflectivity, stability, fidelity and output energy in ΜΟΡΑ system of four-pass configuration are presented Applying optical fiber of 0100 mm core diameter, 6 mJ output energy and 41% SBS reflectivity have been obtained, SBS threshoUsing optical nber with diameter of 0100 mm and ￠200 mm as phase-coryugator, the energy reflectivity, stability, fidelity and output energy in ΜΟΡΑ system of four-pass configuration are presented Applying optical fiber of 0100 mm core diameter, 6 mJ output energy and 41% SBS reflectivity have been obtained, SBS threshold is 0.73 mJ. Applying optical fiber of 0200 nun core diameter, 21 mJ output energy and 37% SBS reflectivity have been obtained, SBS threshold is 1.1 mJ..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 131 (2004)
23-TW Ti:Sapphire Laser System at 10-Hz Repetition Rate
LIN Li-huang, XU Zhi-zhan, LI Ru-xin, WANG Wen-yao, JIANG Yun-hua, YANG Xiao-dong, LENG Yu-xin, ZHANG Zhen-quan, WANG Yi-min, and ZANG Wen-qi
A 23-TW Ti:sapphire laser system at a repetition rate of 10 Hz has been built. After compression, a final output of 778-mJ/33.9-fe pulse centered at 790 nm was obtained The characteristics of the 23-TW Ti:sapphire laser system are presented.A 23-TW Ti:sapphire laser system at a repetition rate of 10 Hz has been built. After compression, a final output of 778-mJ/33.9-fe pulse centered at 790 nm was obtained The characteristics of the 23-TW Ti:sapphire laser system are presented..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 134 (2004)
Development about the Research of Semiconductor Saturable Absorption Mirror
WANG Yong-gang, MA Xiao-yu, and ZHANG Zhi-gang
In this article, the history of development of ultrashort laser technology in China and abroad is introduced as well as the manufacture and the application in solid-state lasers of many kinds of semiconductor saturable absorption mirrors (SESAMs) with different wavelengths. The several general technologies and applicatIn this article, the history of development of ultrashort laser technology in China and abroad is introduced as well as the manufacture and the application in solid-state lasers of many kinds of semiconductor saturable absorption mirrors (SESAMs) with different wavelengths. The several general technologies and application methods to make SESAMs are analyzed The three types of SESAMs at wavelength of 1.06 μτη made by metal organic vapor deposition (MOCVD) were studied The passive mode-locking of Nd:YAG laser with SESAM was realized. The pulse duration is 10 ps; Frequency is 150 MHz; Output power is above 100 mW..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 137 (2004)
Investigation of the Excited State Dynamics of a Novel Porphyrin Side-Chain Polymer
WANG Hui, DENG Li, HUANG Ya-ping, ZHAO Fu-li, Lin Wei-zhu, WANG Jian, NIU Yong-ping, and LIANG Zhao-xi
The excited-state dynamics and third-order nonlinear optical properties of a novel porphyrin side-chain polymer, 5-hydroxy-10,15,20-triphenyl-porphyrin-poly(glycidyl methacrylate) (HTPP-PGMA) have been comparatively studied with a monomelic compound, 5, 10, 15, 20-tetraphenylpoipliyrin (TPP) by using picosecond and femThe excited-state dynamics and third-order nonlinear optical properties of a novel porphyrin side-chain polymer, 5-hydroxy-10,15,20-triphenyl-porphyrin-poly(glycidyl methacrylate) (HTPP-PGMA) have been comparatively studied with a monomelic compound, 5, 10, 15, 20-tetraphenylpoipliyrin (TPP) by using picosecond and femtosecond transient absorption and fluorescence spectroscopy techniques. The ultrafast initial fluorescence decay (-300 ps) and has been observed ?л HTPP-PGMA, which is absence in TPP. Picosecond transient mirrorless optical bistable responses have been observed in both HTPP-PGMA and TPP. The HTPP-PGMA exhibits a faster decay of the output pulses. The ultrafast excited-state dynamics observed in HTPP-PGMA can be explained by the charge transfer (CT) between the porphyrin chromophores..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 140 (2004)
Study on Passively Mode-Lock Using a Semiconductor Saturable Absorber Mirror
YANG Yun-feng, ZHU Xiao, QI Li-jun, SONG Ting-ting, and QIU Fu-sheng
The structure and the parameters of semiconductor saturable absorber mirror (SESAM) are introduced The principle of passively mode-lock is analysed. The optimized project is raised in three different aspects after a discussion about the reason of Q-switched profile mode-locking.The structure and the parameters of semiconductor saturable absorber mirror (SESAM) are introduced The principle of passively mode-lock is analysed. The optimized project is raised in three different aspects after a discussion about the reason of Q-switched profile mode-locking..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 143 (2004)
Spatial Chirp of the Nonlinear Crystal for a Femtosecond BBO Optical Parametric Oscillator
MA Jing, ZHANG Ruo-bing, ZHAO Hua-jun, ZHANG Wei-li, and WANG Qing-yue
The spatial chirp of the nonlinear crystal for a femtosecond BBO ΟΡΟ is calculated theoretically and analyzed The oscillating loops in the resonant cavity and the optical paths in the nonlinear crystal of OTO for different wavelength rays are given· The analytical expressions of the spatial chirp in the nonlinear The spatial chirp of the nonlinear crystal for a femtosecond BBO ΟΡΟ is calculated theoretically and analyzed The oscillating loops in the resonant cavity and the optical paths in the nonlinear crystal of OTO for different wavelength rays are given· The analytical expressions of the spatial chirp in the nonlinear crystal are deduced. Moreover, variation of the spatial chirp with cavity parameters is calculated..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 146 (2004)
Study of an Acousto-Optic Programmable Dispersion Filter for the Femtosecond Pulse Compression
ZHAO Hua-jun, ZHANG Ruo-bing, MA Jing, ZHANG Zhi-gang, and WANG Qing-yue
Acousto-optic programmable filter (AOPDF) as an amplitude and phase modulator is introduced It can compensate in real time for dispersion and precompensate for gain narrowing in femtosecond chirp-pulse amplifier (CPA). Numerical simulation shows the characteristic of the AOPDF in the femtosecond pulse compression whichAcousto-optic programmable filter (AOPDF) as an amplitude and phase modulator is introduced It can compensate in real time for dispersion and precompensate for gain narrowing in femtosecond chirp-pulse amplifier (CPA). Numerical simulation shows the characteristic of the AOPDF in the femtosecond pulse compression which utilizes the LiNb03 crystal as an acousto-optic crystal..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 149 (2004)
Realization and Analysis for a SPIDER Apparatus
HE Tie-ying, CHAI Lu, WANG Qing-yue, and ZHANG Zhi-gang
This paper demonstrated the experiment results for characterizing femtosecond pulses from a Ti:sapphire oscillator with a SPIDER apparatus. The model of spectral filter of the nonlinear crystal in a SPIDER apparatus has been constructed. The relationship between the bandwidth of the conversion efficiency of BBO crystalThis paper demonstrated the experiment results for characterizing femtosecond pulses from a Ti:sapphire oscillator with a SPIDER apparatus. The model of spectral filter of the nonlinear crystal in a SPIDER apparatus has been constructed. The relationship between the bandwidth of the conversion efficiency of BBO crystal and the crystal thickness has been calculated The choice range of the BBO thickness adapting to the different widths of pulses has been discussed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 152 (2004)
Storage of Ultrashort Optical Pulses in a Resonant Photonic Bandgap Structure
WU Jia-wen, XIAO Wan-neng, ZHAO Ji, SHAO Hui-guo, ZHOU Jian-ying, and J. P. Prineas
A practical method of slowing and stopping an incident ultrashort light pulse with a resonantly absorbing Bragg reflector is demonstrated numerically. It is shown that an incident laser pulse with suitable pulse area evolves from a given pulse waveform into a stable, spatially-localized oscillating or standing gap soliA practical method of slowing and stopping an incident ultrashort light pulse with a resonantly absorbing Bragg reflector is demonstrated numerically. It is shown that an incident laser pulse with suitable pulse area evolves from a given pulse waveform into a stable, spatially-localized oscillating or standing gap soliton. It is proven that multiple gap solitons can be simultaneously spatially localized, resulting in efficient optical energy conversion and storage in the resonantly absorbing Bragg structure as atomically coherent states..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 155 (2004)
Transients of the Optical Constants for Ta2O5 Film Under Excitation of Femtosecond Laser Pulses
LIU Jian-hua, M. Mero, A. Sabbah, and W. Rudolph
Ultrafast changes of reflection and transmission were measured simultaneously for Ta2O6 single layer on fused silica substrate under excitation of femtosecond laser pulses. Peak modifications of -3.4% for index of refraction and 0.042 for extinction coefficient were retrieved respectively by a model of single absorptioUltrafast changes of reflection and transmission were measured simultaneously for Ta2O6 single layer on fused silica substrate under excitation of femtosecond laser pulses. Peak modifications of -3.4% for index of refraction and 0.042 for extinction coefficient were retrieved respectively by a model of single absorption layer on transparent substrate. The maxinia of changes emerged about 100 fs after the pump pulse, and then decayed with a time constant of about 600 fs..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 158 (2004)
Phase-Matched High-Order Harmonic Generation in Static Gas
XIE Xin-hua, ZENG Zhi-nan, LI Ru-xin, CHEN Shu, and XU Zhi-zhan
Phase-matched high-order harmonic generation in Ar gas-filled cell was investigated experimentally. The phase-matched 27th order harmonic driven by a commercially available solid-state femtosecond laser system at 0.55 mJ/pulse energy level and 1 kHz repetition rate was obtained. Spectral blueshift and broadening of higPhase-matched high-order harmonic generation in Ar gas-filled cell was investigated experimentally. The phase-matched 27th order harmonic driven by a commercially available solid-state femtosecond laser system at 0.55 mJ/pulse energy level and 1 kHz repetition rate was obtained. Spectral blueshift and broadening of high-order harmonics were analyzed. Moreover, the source size of high-order harmonic generation was enhanced under the phase-matching condition..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 161 (2004)
Fabrication of Refractive Index-Modulated Grating in Fused Silica by a Femtosecond Laser
GUO Heng-chang, WANG Xi, FANG Ying, PENG Chao, YANG Hong, JIANG Hong-bing, and GONG Qi-huang
The refractive index-modulated grating, performed by line scan in fused silica with a femtosecond laser at wavelength of 810 nm and repetition rate of 1 kHz, were presented Dependence of the refractive index-modulation on femtosecond laser pulse energy, scan speed, spacing period, and scanning repetitions was investigaThe refractive index-modulated grating, performed by line scan in fused silica with a femtosecond laser at wavelength of 810 nm and repetition rate of 1 kHz, were presented Dependence of the refractive index-modulation on femtosecond laser pulse energy, scan speed, spacing period, and scanning repetitions was investigated The refractive Index modulation reached to 3×10-3 after several scanning repetitions. It was revealed that the accumulation effect played a very important role in the formation of refractive index-modulated structures..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 164 (2004)
Active Control of Ultrashort Pulse Spectrmn by Acousto-Optic Programmable Dipersive Filter
HUANG Xiao-jun, WEI Xiao-feng, PENG Han-sheng, WANG Xiao-dong, YUAN Xiao-dong, LIULan-qin, ZENG Xiao-ming, ZHOU Kai-nan, GUOYi, LIN Dong-hui, and ZHANG Xiao-min
It is reported that an acousto-optic programmable dispersive fiber (AOPDF) is applied to an ultrashort pulse in the CPA laser system. The AOPDF is based on a collinear acousto-optic interaction· The acoustic frequency is a variable function of time and provides control over the group delay of the diffracted opticaIt is reported that an acousto-optic programmable dispersive fiber (AOPDF) is applied to an ultrashort pulse in the CPA laser system. The AOPDF is based on a collinear acousto-optic interaction· The acoustic frequency is a variable function of time and provides control over the group delay of the diffracted optical pulse. Simultaneously, the spectral amplitude of the diffracted optical pulse is driven by the acoustic signal's intensity. The AOPDF permits precompensation for gain narrowing through amplitude shaping before amplification. The spectra of the amplified pulse keeps sufficient width after compression, and the ultra-short pulse can be obtained..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 166 (2004)
Self-Starting Femtosecond Ti:Sapphire Laser with Low-Threshold Pump
LING Wei-jun, WEI Zhi-yi, SUN Jing-hua, and WANG Zhaohua
A low-threshold self-starting Kerr-lens mode-locked Ti:sapphire laser was demonstrated by use of a tight focusing cavity design and a semiconductor saturable-absorber mirror (SESAM). With a 3% and a 12% output couplers, mode-locking thresholds as low as 390 mW and 600 mW weve achieved, respectively. Stable femtosecond A low-threshold self-starting Kerr-lens mode-locked Ti:sapphire laser was demonstrated by use of a tight focusing cavity design and a semiconductor saturable-absorber mirror (SESAM). With a 3% and a 12% output couplers, mode-locking thresholds as low as 390 mW and 600 mW weve achieved, respectively. Stable femtosecond laser pulses with average power of 114 mW were generated for pump power at 1.2 W, which correspond to a typical duration of 17 fs and bandwidth of 47 nm..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 169 (2004)
Properties of Super-Continuum Spectra Generated in Photonic Crystal Fibers with Symmetric and Asymmetric Structure
ZHANG Jun, WEI Zhi-yi, HAN Hai-nian, ZHAO Ling-hui, and Nie Yu-xin
This paper reports the generation of super-continuum spectra in the photonic crystal fibers with a symmetric and asymmetric structure and ultra-broaden spectra covered from UV to infrared were obtained in both nbers. Especially, the generation of third harmonic wave was observed with the asymmetric photonic crystal fibThis paper reports the generation of super-continuum spectra in the photonic crystal fibers with a symmetric and asymmetric structure and ultra-broaden spectra covered from UV to infrared were obtained in both nbers. Especially, the generation of third harmonic wave was observed with the asymmetric photonic crystal fiber, the polarization effects of super-continuum spectra were also studied Using the polarization effect, it will enable us to control the distribution and relative intensities of super-continuum components, which is very beneficial in many applications..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 172 (2004)
Primary Observation of Slow Light Propagation in Solid State Material
ZHANG Yun-dong, FAN Bao-hua, YUAN Ping, and MA Zu-guang
Slow light propagation is initially observed in solid state materials at room temperature. The slowdown of light resulting from dramatic change of refractive index by spectral hole technique in Ruby at 514.5 nm is investigated. Measured delay is about 2.31 ms, corresponding to group velocity as low as 43.215 m/s.Slow light propagation is initially observed in solid state materials at room temperature. The slowdown of light resulting from dramatic change of refractive index by spectral hole technique in Ruby at 514.5 nm is investigated. Measured delay is about 2.31 ms, corresponding to group velocity as low as 43.215 m/s..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 175 (2004)
Surface-Enhanced Raman Scattering of the Liquid Crystal
ZHOU Hai-guang, and WANG Fu-lin
By using surface-enhanced Raman scattering (SERS), the orientation of liquid crystal 5CB absorbed on nano-roughened Ag and Au electrodes was studied. The results suggest that the orientation of LC 5CB absorbed on nano-roughened Ag electrode is different from that of Au electrode. This implies that the interaction betweBy using surface-enhanced Raman scattering (SERS), the orientation of liquid crystal 5CB absorbed on nano-roughened Ag and Au electrodes was studied. The results suggest that the orientation of LC 5CB absorbed on nano-roughened Ag electrode is different from that of Au electrode. This implies that the interaction between LC 5CB and Ag is different from the interaction between LC 5CB and Au. The conclusion is that the orientation of LC 5CB absorbed on nano-roughened Ag electrode is perpendicular, and the oriental ton of LC 5CB absorbed on nano-roughened Au electrode is more complicated, including parallel, perpendicular and tilted..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 177 (2004)
Second-Order Optical Nonlinearity of Glasses in the Al2O3-Na2O-B2O3-SiO2 Pseudoquadruplex System
WANG Xue-feng, GU Shao-xuan, ZHAO Xiu-jian, and YU Jia-guo
Electrical/thermal poling, heat treatment and ultrasonic acid treatment were used to investigate the properties of second harmonic generation in the 1.6Аl2O3-6.1Na2O-24.8B2O3-67.5SiO2(wt-%) pseudoquadruplex glass, together with UV-Vis-NIR optical transmission spectra, scanning electron microscopy (SEM), X-ray dlffiactiElectrical/thermal poling, heat treatment and ultrasonic acid treatment were used to investigate the properties of second harmonic generation in the 1.6Аl2O3-6.1Na2O-24.8B2O3-67.5SiO2(wt-%) pseudoquadruplex glass, together with UV-Vis-NIR optical transmission spectra, scanning electron microscopy (SEM), X-ray dlffiaction (XRD) and Maker fringe measurements. The results show that electrical/thermal poling induces the generation of second harmonic (SH) signal in the glass. When thermal field is constant (280 ℃), the Intensity of SH signal increases with increasing electric field and poling time. Heat treatment induces the combination and growth of the mlcrocrystals in the glass, thus at some angles the strong SH signal appears. Ultxasonic acid treatment induces the formation of thin microcrystals at surface and the strong SH signal appears in the broad range of angles. The existed crystallized phase in this glass is α-cristobalite..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 181 (2004)
Study on the Fluctuation of Colliding-Enhanced YAG Phase-Conjugate Ring Laser Cavity
QU Jun, ZHANG Wei-jun, GAO Xiao-ming, LIU An-ling, HUANG Wei, PEI Shi-xin, YANG Yong, and SHAO Jie
In this paper, a colliding-enhanced YAG phase-coryugate ring laser cavity is reported which has low threshold and lower fluctuation comparing with line phase-conjugate resonator. The output energy and peak power fluctuation under different conditions are given.In this paper, a colliding-enhanced YAG phase-coryugate ring laser cavity is reported which has low threshold and lower fluctuation comparing with line phase-conjugate resonator. The output energy and peak power fluctuation under different conditions are given..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 185 (2004)
Picoseconds Pulse Generation by Two-Stage Stimulated Brillouin Scattering Compressor
WANG Chao, LV Zhi-wei, and HE Wei-ming
The theory model is transient model including the effect of the pump depletion. The results of numerical simulation are consistent with the experimental results. The picoseconds pulse was obtained by two-stages stimulated Brillouin Scattering (SBS) compressor to compress 8 ns laser pulse. The experiment used CCl4 as SBThe theory model is transient model including the effect of the pump depletion. The results of numerical simulation are consistent with the experimental results. The picoseconds pulse was obtained by two-stages stimulated Brillouin Scattering (SBS) compressor to compress 8 ns laser pulse. The experiment used CCl4 as SBS medium. The laser pulse was compressed to 1.5 ns by the first stage compressor. In the second compress stage, by the use of 532 nm and 1064 nm as a pump, separately, the shortest pulse of 60 ps was obtained. The results show that the pulse with the duration shorter than the medium acoustic lifetime can be achieved by SBS compressor. The results of numerical simulation are consistent with the experimental results..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 188 (2004)
Study on Monocycle-Like Optical Pulse
CHEN Xiao-wei, XIANG Wang-hua, LIN Li-huang, and LI Ru-xin
Principles for monocycle-like pulse generation by crossed phase modulation in the silicon fiber are introducea in this paper. By using split-step Fourier method the effect of pulse parameters on the spectra broadening is numerically analyzed in detail. Finally, ultrabroad-band spectrum ranging from 200 to 1000 THz is aPrinciples for monocycle-like pulse generation by crossed phase modulation in the silicon fiber are introducea in this paper. By using split-step Fourier method the effect of pulse parameters on the spectra broadening is numerically analyzed in detail. Finally, ultrabroad-band spectrum ranging from 200 to 1000 THz is achieved, and the Fourier transform of this spectrum can give a near monocycle optical pulse..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 191 (2004)
Coulomb Explosion and Angular Distribution of Ions in Intense Femtosecond Laser
MA Ri, REN Hai-zhen, CHEN Jian-xin, LI Xia, WU Cheng-yin, YANG Hong, and GONG Qi-huang
Mass spectras of CS2, CH, and CH3OH were measured with a time-of-flight (TOF) under conditions with laser intensity varying from 1013 W/cm2 to 1016 W/cm2 and a pulse duration of 110 fs. Different mass spectras with linear polarization and circularly polarization were observed The angular distribution of ions of CS2 indMass spectras of CS2, CH, and CH3OH were measured with a time-of-flight (TOF) under conditions with laser intensity varying from 1013 W/cm2 to 1016 W/cm2 and a pulse duration of 110 fs. Different mass spectras with linear polarization and circularly polarization were observed The angular distribution of ions of CS2 indicated a spatial alignment from the coulomb explosion of highly charged parent ion. Moreover, the comparision of mass spectra with CH4 and CH3OH does not exhibit a feature of the double peak splited from C ions, which manifestes a concerted explosive process of CH4 This is consistent with the results of CS2 analysed by the method of the kinetic energy release(KER)..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 195 (2004)
Theory of Kerr-Lens Mode-Locked Cr4+:YAG Laser
SONG Li-jun, SONG Yan-rong, and ZHOU Guo-sheng
Based on the traditional ABCD law, the relative variation of spot size in the laser medium is analyzed. The results show that the introduction of SESAM destroyed the continuity of the laser stability and enhanced the nonlinearity of the laser. So the mode-locked pulses are generated easily due to the SESAM. The spectruBased on the traditional ABCD law, the relative variation of spot size in the laser medium is analyzed. The results show that the introduction of SESAM destroyed the continuity of the laser stability and enhanced the nonlinearity of the laser. So the mode-locked pulses are generated easily due to the SESAM. The spectrum width of 40пш has been obtained experimentally..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 198 (2004)
Optical Limiting Characteristic of Semiconductor Nano-Particles Bi2S3 and NiS
ZHANG Yun-dong, ZHU Jun-jie, ZHANG Yun-jun, and YUAN Ping
The optical limiting characteristic of semiconductor nano-particles Bi2S3 and NiS were investigated in experiment. Their nonlinear limiting thresholds are 0.11 J/cm2 and 0.21 J/cm2, respectively. From the result of the open Z-scan for the samples, the nonlinear absorption coefficients of Bi2S3 and NiS are β≈8 cm/GW andThe optical limiting characteristic of semiconductor nano-particles Bi2S3 and NiS were investigated in experiment. Their nonlinear limiting thresholds are 0.11 J/cm2 and 0.21 J/cm2, respectively. From the result of the open Z-scan for the samples, the nonlinear absorption coefficients of Bi2S3 and NiS are β≈8 cm/GW and β≈9 cm/GW, respectively. It was found that the measured result of the closed scan of NiS in alcohol solution indicates the self-focusing effect in it. That is, the nonlinear refractive index of NiS solution n2>0, corresponding γ≈2.66×10-41 cm2/GW..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 201 (2004)
Soliton Interference in Polarization Division Multiplexing System With Higher-Order Effects
ZHU Hai-dong, and Li Qi-liang
In the Manakov PDM system, solitons polarize on two orthogonal axes, which can overcome the interaction of the solitons, increase the information rate of the communication system. The solitons are assumed to be the sech forms, and the TOD and Kerr nonlinearity can not be ignored. The envelops of the solitons satisfy thIn the Manakov PDM system, solitons polarize on two orthogonal axes, which can overcome the interaction of the solitons, increase the information rate of the communication system. The solitons are assumed to be the sech forms, and the TOD and Kerr nonlinearity can not be ignored. The envelops of the solitons satisfy the extended coupled Manakov equations。 The equations can be solved by the Lagrange method and perturbation theory..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 204 (2004)
Theory and Experiment of Stimulated Brillouin Scattering Pumped with Broadband Laser
WANG Chao, LV Zhi-wei, LIN Dian-yang, WANG Xiao-hui, ZHAO Xiao-yan, TANG Xiu-zhang, ZHANG Hai-fen, and SHAN Yu-shen
The paper presents a theory model to describe the process of stimulated Brillouin scattering (SBS) pumped with broadband laser. The mode is assumed that the broadband spectral is made of many narrow bands. It considers the effect of pump depletion and optical breakdown on SBS. The maximum reflectivity of 45% is got in The paper presents a theory model to describe the process of stimulated Brillouin scattering (SBS) pumped with broadband laser. The mode is assumed that the broadband spectral is made of many narrow bands. It considers the effect of pump depletion and optical breakdown on SBS. The maximum reflectivity of 45% is got in experiment The theoretical results are consistent with the experiment..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 207 (2004)
A New Approach to the Problems of Third-Order Dispersion in the Fiber with Slowly Decreasing Dispersion
LI Chao, and WU Ting-wan
In this paper, a brief mathematic method is used to analyze the compression effect of negative third-order and fourtii-order dispersion on soliton in nonlinear Schrodinger equation involved with high-order dispersion in the fiber with slowly decreasing dispersion. The mathematic expressions of the shift of the optimum In this paper, a brief mathematic method is used to analyze the compression effect of negative third-order and fourtii-order dispersion on soliton in nonlinear Schrodinger equation involved with high-order dispersion in the fiber with slowly decreasing dispersion. The mathematic expressions of the shift of the optimum compression length are got Their predictions agree quite well with either the known-experiment results or numerical simulation. At the same time, the research is also extended in the positive third-order dispersion and dark soliton..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 210 (2004)
Development of Laser Technology about the "Laser 2003 World of Photonics"
[in Chinese]
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 213 (2004)
Study on Tracking Experiment of Imaging Laser Radar Based on DSP
WANG Qi, SUN Jian-feng, LI Qi, LU Wei, ZHOU Lai, SHANG Tie-Uang, and TIAN Zhao-shuo
In this paper, a tracking method of imaging laser radar that is based on DSP is implemented. By using designed digital image processing circuit board and server components, adopting centroid tracking algorithm, control singal output by DSP and complex programmable logic device (CPLD). The result indicates that trackingIn this paper, a tracking method of imaging laser radar that is based on DSP is implemented. By using designed digital image processing circuit board and server components, adopting centroid tracking algorithm, control singal output by DSP and complex programmable logic device (CPLD). The result indicates that tracking experiment of imaging laser radar is finished well..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 215 (2004)
Application and Development of Under-Water Target Detection by Laser
ZHANG Zheng-yu, ZHOU Shou-huan, ZHANG Xiao-long, XUAN Fei, and SUI Xiao-lin
Characteristic, advantage, development and application of under-water target detection by laser are introduced in this paper. Imaging pattern is analyzed and development tendency is summarized.Characteristic, advantage, development and application of under-water target detection by laser are introduced in this paper. Imaging pattern is analyzed and development tendency is summarized..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 218 (2004)
Applications of Light Emitting Diode Technology in Photobiology and Medicine
LIU Jiang, LIU Cheng-yi, FAN Guang-han, and WANG Xiao-jing
The investigations and applications of light emitting diode (LED) technology in plant, animal cell, animal model, human clinical, biomaterial and environment protection are summarized in this paper.The investigations and applications of light emitting diode (LED) technology in plant, animal cell, animal model, human clinical, biomaterial and environment protection are summarized in this paper..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 221 (2004)
Research of Some Key Technologies in UV Communication System
YANG Jian-kun, CHANG Sheng-li, YANG Jun-cai, JIA Hong-hui, and Li Xiu-jian
Ultraviolet light communication is a new means of optical information transmission technology developed since 1990's. In this paper, some key technologies developed from the experiment are described in detail. These technologies include the designs of high speed UV source frequency modulator, high sensitive opticalUltraviolet light communication is a new means of optical information transmission technology developed since 1990's. In this paper, some key technologies developed from the experiment are described in detail. These technologies include the designs of high speed UV source frequency modulator, high sensitive optical receiver system and the design of weak signal detect and process modular, etc. The UV communication system has accomplished good voice and high speed digital data bidirectional communication in semi-duplex way and its maximal communication baud rate is up to 9600 bps which is twice as the baud rate of the UV communication system made by GTE company for USA navy in 2000. Furthermore, in some distance, the system can achieves a non-line-sight communication..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 224 (2004)
Laser Diode End-Pumped Er-Yb Co-Doped Phosphate Glass Waveguide Amplifiers
CHEN Hai-yan, DAI Ji-zhi, YANG Ya-pei, HUANG Xiu-jiang, GUAN Zhou-guo, and LIU Yong-zhi
A comprehensive review on laser diode end-pumped Er-Yb co-doped phosphate glass waveguide amplifiers is presented It consists of Er-Yb co-doped phosphate glass, structure and characteristics of optical waveguide amplifiers, etc. The combination of this good performance and potential low cost makes these amplifier devicA comprehensive review on laser diode end-pumped Er-Yb co-doped phosphate glass waveguide amplifiers is presented It consists of Er-Yb co-doped phosphate glass, structure and characteristics of optical waveguide amplifiers, etc. The combination of this good performance and potential low cost makes these amplifier devices attractive for a variety of applications including boosters, in-line, optical lossless splitters, optical CATV systems and metro networks..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 227 (2004)
Fabrication of Low Loss Single-Mode Rib Waveguides in Silicon-on-Insulator
LIN Zhi-lang, CHENG Xin-li, WANG Yong-jin, and ZHANG Feng
Theoretical analyses and experiments have been implemented to minimize surfaces induced scattering loss and Fresnel reflection loss which dominate the losses in silicon-on-insulator rib waveguides. 20 mm long single-mode rib waveguides samples with the fiber-chip-fiber insertion losses below 2.15 dB have been fabricateTheoretical analyses and experiments have been implemented to minimize surfaces induced scattering loss and Fresnel reflection loss which dominate the losses in silicon-on-insulator rib waveguides. 20 mm long single-mode rib waveguides samples with the fiber-chip-fiber insertion losses below 2.15 dB have been fabricated in thick-film silicon-on-insnlator..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 230 (2004)
Experiment of Long-Period Fiber Gratings Fabricated by CW CO2 Laser Pulses
LUO Shou-yu, YAN Ming, LI Li-li, ZHANG Zhi-ming, and XIA Yu-xin
In this paper, long-period fiber gratings are analyzed by using the coupled mode theory, and the recent progress of the fabrication technology using CW CO2 laser pulses is briefly presented, and stiffiiess of mode coupling changing with the length of grating is observed.In this paper, long-period fiber gratings are analyzed by using the coupled mode theory, and the recent progress of the fabrication technology using CW CO2 laser pulses is briefly presented, and stiffiiess of mode coupling changing with the length of grating is observed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 233 (2004)
Anti-Noise Properties of Micro-Cavity Semiconductor Laser for Spontaneous Emission Factor Modulation
WANG Ying-long, CHU Li-zhi, ZHENG Yun-long, ZHOU Yang, ZHANG Rong-mei, YAN Zheng, and SHANG Yong
Supposing that input modulation signal is actual phonetic signal and its adjoint noise is additive white noise, for spontaneous emission factor modulation, by using small signal appoximatation, the signal-to-noise ratio (SNR) gain is derived in various parameters through frequency domain analysis against laser in the pSupposing that input modulation signal is actual phonetic signal and its adjoint noise is additive white noise, for spontaneous emission factor modulation, by using small signal appoximatation, the signal-to-noise ratio (SNR) gain is derived in various parameters through frequency domain analysis against laser in the premise of large input SNR The results of numerical simulation show that when the pass band range of the band pass filter (BPF) is 300-3400 Hz, signal-to-noise ratio gain oscillates with bias current in the background of constant 1; while the pass band range of BPF increases to a certain degree, tunning-up modulating bias current and parameters of the cavity can improve the anti-noise properties of laser..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 235 (2004)
Study on a Novel Interleaver Based on Dual-Pass Mach-Zehnder Interferometer
ZHANG Ting, CHEN Kai, and SHENG Qiu-qin
A novel interleaver based on dual-pass Mach-Zehnder interferometer is proposed, of which the principle and the characteristics are analyzed both on theoiy and experiment Compared with the traditional M-Z interferometer, the isolation of the new structure is enhanced greatly. When the frequency spacing reaches 50 GHz, iA novel interleaver based on dual-pass Mach-Zehnder interferometer is proposed, of which the principle and the characteristics are analyzed both on theoiy and experiment Compared with the traditional M-Z interferometer, the isolation of the new structure is enhanced greatly. When the frequency spacing reaches 50 GHz, its isolation is more than 25 dB. The experiment result is of importance in the application of interleaver..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 238 (2004)
Systematic Study of Multi-Function DWDM Optical Filter Composite Module
MENG Yi-chao, HUANG Zhao-ming, WANG Lu-tang, PENG Fen, and Fang Nian
A novel multi-function DWDM optical filter composite module is proposed and systematically studied, complete theoretical model and numerical simulation results are givea Performance demanded for them by DWDM optical network and fabrication techniques are discussed also. Much effort was devoted to the modeling, design aA novel multi-function DWDM optical filter composite module is proposed and systematically studied, complete theoretical model and numerical simulation results are givea Performance demanded for them by DWDM optical network and fabrication techniques are discussed also. Much effort was devoted to the modeling, design and analysis of bi-directional finite impulse response (FIR) type de-interieaver based on cascaded asymmetric M-Z interferometer. Adoption of wideband 3×3 fiber coupler in the structure provides such advantage as in-line monitoring of the fabrication process conveniently, meanwhile, attached by other optical components like optical circulator, fiber grating dispersion compensator, F-P wavelength channel monitor and MZI-DWDM, its function is strengthened, which is important for intelligent DWDM ail-optical network especially..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 241 (2004)
A Tbit/s Hybrid Optical Router Switching System Architecture
ZHOU Xin-jun, CAO Ming-cui, LUO Zhi-xiang, LUO Feng-guang, and XU Jun
A new Tbit/s large capacity hybrid optical router switching system architecture was discribed, which employs high speed optical interconnection network to transmit informaUon, VCSEL/PIN as optoelectronic and electrooptical device, and high speed large scale integrate circuit to process the information· The proposeA new Tbit/s large capacity hybrid optical router switching system architecture was discribed, which employs high speed optical interconnection network to transmit informaUon, VCSEL/PIN as optoelectronic and electrooptical device, and high speed large scale integrate circuit to process the information· The proposed architecture uses high speed packet switching circuit chip, scalable switching fabric and shared buffer output queue scheme. The result shows that it is feasible to construct a router switching core with cell loss rate below 10^, port rate at 2.5 Gb/s and scalable 1024×1024 switching fabric..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 245 (2004)
Study on the Technology for Micro-Porus Polymer Waveguide
ZHU Da-qing, YANG Zhen-yu, JIN Xi, LIU Yong-jun, and HAN Xiao-xing
The mirco-porus PMMA film was made by removing the PS phase with cyclohexane from the mixture of PS and PMMA which were dissolved with THF. The microstxucture and the refractive index of the film and the light loss (632.8 nm) in the film were studied.The mirco-porus PMMA film was made by removing the PS phase with cyclohexane from the mixture of PS and PMMA which were dissolved with THF. The microstxucture and the refractive index of the film and the light loss (632.8 nm) in the film were studied..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 249 (2004)
Locating Method for Laser Danger Source Based on Doppler Effect
WANG Lian-fen, ZHANG Qing-hua, and ZHAO Xuan-ke
From the point of view of relativity principle and Doppler effect, the formula of changing value in receiver frequency for double antenna directional locating device is derived,. Under the circumstance of ignoring high order-small, it shows that Doppler frequency deviation is the sine function of angle between laser emFrom the point of view of relativity principle and Doppler effect, the formula of changing value in receiver frequency for double antenna directional locating device is derived,. Under the circumstance of ignoring high order-small, it shows that Doppler frequency deviation is the sine function of angle between laser emitting direction and reference direction of receiver. At some special location, frequency deviation is zero. According to this location of "zero point", the danger signal direction of laser can be determined..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 252 (2004)
Single Pulse Laser Ablation on Superabrasives Grinding Wheels by Nd:YAG Lasers
XIE Xiao-zhu, LI Li-jun, and CHEN Gen-yu
Acousto-optic Q-switched Nd YAG pulse laser is employed to dress resin bonded superabrasives wheels in orthogonal direction. The crater depth of single pulse is measured by Taly surface roughness instrument and the surface morphology of ablated crater is observed by light microscope (LM). This рrфеr theoretically analyAcousto-optic Q-switched Nd YAG pulse laser is employed to dress resin bonded superabrasives wheels in orthogonal direction. The crater depth of single pulse is measured by Taly surface roughness instrument and the surface morphology of ablated crater is observed by light microscope (LM). This рrфеr theoretically analyzed the formation of ablated crater, experimentally established the relation between the crater depth and pulse laser intensity, and studied on the crater depth influenced by laser parameters: average power, pulse repetition frequency and defocus distance. Experiment indicates that, on the basis of single pulse ablation on the wheels, a favorable topography is obtained by selecting suitable laser parameters..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 254 (2004)
PLC Control System of 3500 W Fast Axial Flow CO2 Laser
[in Chinese], and [in Chinese]
A PLC control system for 3500 W fast axial flow C02 laser is introduced in this article. The study of control programms focuses on the analog parameters of gas & laser power. This PLC software based on IEC1130 is stabilization, simple and credibility.A PLC control system for 3500 W fast axial flow C02 laser is introduced in this article. The study of control programms focuses on the analog parameters of gas & laser power. This PLC software based on IEC1130 is stabilization, simple and credibility..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 257 (2004)
Research on Large Numerical Aperture Multiple-Composition Glass Incoherent Flexible Fibre
YU Feng-xia, ZHOU Yan-yan, YU Li-ting, WANG Xin-wei, LIU Yu, TANG Ji-long, and ZHANG Wen-tao
The incoherent flexible fibre, made through matched drawing by using SiO2-B2O3-La2O3-Nb2O5-RO systematic glass as core and using low refractive index material made by ourselves as cladding, has a numerical aperture of 0.8725 and on angle of light reception of 122°. It enlarges the observing scope of the medical faThe incoherent flexible fibre, made through matched drawing by using SiO2-B2O3-La2O3-Nb2O5-RO systematic glass as core and using low refractive index material made by ourselves as cladding, has a numerical aperture of 0.8725 and on angle of light reception of 122°. It enlarges the observing scope of the medical fabric endoscope on the pathological changes of inner cavities of human viscera. It satifies the special requirement of observation and diagnosis on medical apparatus and instruments.In this article, the scope of the fundamental composition of SiO2-B2O3-La2O3-Nb2O5-RO system is desgivened, the requirement on the properties of the materical which is used to make large numerical aperture fibre is discussed, some factors which have influence on the performance of fibre are analysed, and the result of preliminary research is given at the end..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 260 (2004)
Study of Near-Infrared Tunable Diode Laser Spectrometer
HUANG Wei, GAO Xiao-ming, ZHANG Wei-jun, PEI Shi-xin, QU Jun, SHAO Jie, LI Xiao-yun, YANG Yong, and LEI Li-qiao
Absorption spectroscopy with tunable diode laser (TDLAS) in the near-infrared region is a well-known technique for the chemical analysis of gas mixtures and sensitive detection. In this paper a TDLAS measurement system is presented which can be used to integrated system detect trace gas and control process.Absorption spectroscopy with tunable diode laser (TDLAS) in the near-infrared region is a well-known technique for the chemical analysis of gas mixtures and sensitive detection. In this paper a TDLAS measurement system is presented which can be used to integrated system detect trace gas and control process..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 263 (2004)
Microstructure and Properties of Laser-Induced Combustion Synthesis Zr55Ti10.8Al17.1Ni17.1 Alloy
WANG Yan-fang, WANG Cun-shan, LI Gang, PAN Xue-min, XIA Yuan-Uang, and DONG Chuang
Bulk metallic glasses, like many crystalline intermetallics, have large negative enthalpy of mixing among the m^jor constituent elements, and hence are potential candidates of self-propagating high-temperature reaction systems. Based on this characteristic, the laser-induced combustion synthesis (LCS) technique is applBulk metallic glasses, like many crystalline intermetallics, have large negative enthalpy of mixing among the m^jor constituent elements, and hence are potential candidates of self-propagating high-temperature reaction systems. Based on this characteristic, the laser-induced combustion synthesis (LCS) technique is applied to fabricate Zr55Ti10.8Al17.1Ni17.1 alloy. The product consists of amorphous, Zr2Ni and Ζr6Al2Ni intermetallic phases and Ti/Zr solid solution· Compared with single amorphous alloy, the product shows higher microhardness and lower friction coefficient..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 267 (2004)
Fatigue Growth Rates of Laser Shock Processed Metal Sheet
[in Chinese], and [in Chinese]
In this paper, compact tension(CT) specimens of 2024T62 sheet with thickness of 2.5 mm, a superalloy with thickness of 1.5 mm and a high-strength steel sheet with thickness of 1.7 mm were treated by laser shock processing, three spots with diameter of 6 mm overlapped along the extension line of precut crack. The fatiguIn this paper, compact tension(CT) specimens of 2024T62 sheet with thickness of 2.5 mm, a superalloy with thickness of 1.5 mm and a high-strength steel sheet with thickness of 1.7 mm were treated by laser shock processing, three spots with diameter of 6 mm overlapped along the extension line of precut crack. The fatigue crack growth rates of laser shock processed specimens were compared with those without LSP, the results show that effects of laser shock strengthening have much difference along the crack growth line, the fatigue growth rates can't be fitted by the Paris formula, but decreased in whole..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 270 (2004)
Five-Fold Resonator CO2 Laser Welding Equipment with High Beam Quality
HU Chang-kui, CHEN Pei-feng, WANG Tao, and LIANG Jun
This paper introduced a whole set of high-power СОr laser welding equipment with high beam quality, analyzed the optical system primarily, including the five-fold resonator of laser, three workspace light switched system, reflect focused system. The output power of the laser reached 2.5 kW and the output power fluctuatThis paper introduced a whole set of high-power СОr laser welding equipment with high beam quality, analyzed the optical system primarily, including the five-fold resonator of laser, three workspace light switched system, reflect focused system. The output power of the laser reached 2.5 kW and the output power fluctuation is ±4%。The ТЕМ00+ТЕМ01 laser beam with 1.6 mrad divergent angle has been obtained by the design of five-folded resonator, The ability of laser has been used properly and the efficiency has been improved by the use of three-workspace switch. The metal paraboloid reflector has been used to focus the beam in order to overcome the influence of thermal lens and spherical difference. Meanwhile, the 20CrMnTi alloy gears in automobile, gear-box have been welded, the welded seam with good appearance was obtained, the depth/width of the welded seam exceed 3:1, the thermal influenced zone is narrow and the melted zone has no shortcoming..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 273 (2004)
Signal Process of Laser Location-Tracking System for Hoist Based on Wavelet Transform
ZHOU Meng-rаn, and LIU Wen-qing
The Tracking system can measure the traveling distance with the laser working in infra-red wave band by measuring the phase difference with modulated light wave shuttling the measured distance. Since noise contained signal process of the hoist's distance measuring is realized by wavelet transform. Based on differenThe Tracking system can measure the traveling distance with the laser working in infra-red wave band by measuring the phase difference with modulated light wave shuttling the measured distance. Since noise contained signal process of the hoist's distance measuring is realized by wavelet transform. Based on different properties of noise and the signal working in different scale, noise can be eliminated by consulting the threshold value, after that real signal will be reconfigured. This system can improve the precision of distance measure by showing the hoist's real location exactly. Date process of laser location-tracking signal can be realized by the simulating of MATLAB software. All in ail, this system can realize digital control of the riser's location and speed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 276 (2004)
Diagnostics of Singlet Oxygen Generator for Chemical Oxygen-Iodine Laser with Nitrogen Dilution
ZHAO Wei-li, FANG Ben-jie, WANG Zeng-qiang, CHEN Fang, ZHANG Yue-long, DUO Li-ping, Yu-qi, and SANG Feng-ting
A jet-type singlet oxygen generator in which chlorine flow rate is 0.1mol/s was researched The measurement results of chlorine utilization, (O2a1Δ) yield and water vapor indicated that this kind of generator has the same ability as that with helium dilution when the nitrogen flow rate is not more than third times of chA jet-type singlet oxygen generator in which chlorine flow rate is 0.1mol/s was researched The measurement results of chlorine utilization, (O2a1Δ) yield and water vapor indicated that this kind of generator has the same ability as that with helium dilution when the nitrogen flow rate is not more than third times of chlorine..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 279 (2004)
Study of Imaging Laser Radar Display Platform
WANG Hai-hong, WANG Qi, and Gu Ya-long
A display platform is developed for imaging laser radar system, as well as the design, compose and software flow of display platform are introduced By the use of Visual C++ 6.0 in Windows system, the intensity and range image of the target is displaied Further, display platform realizes the grayscale transformation of A display platform is developed for imaging laser radar system, as well as the design, compose and software flow of display platform are introduced By the use of Visual C++ 6.0 in Windows system, the intensity and range image of the target is displaied Further, display platform realizes the grayscale transformation of the image, and gets the different pictures with the different grayscale transformation of the same image. Display platform can also select the specific range value of the target before detecting and save the image data. The soft met the need of laser radar imaging through experiment..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 282 (2004)
An Improved Laser Range Gated Imaging System Based on DSP
XU Xiao-wen, GUO Jin, FU You-yu, and ZHANG Wei
It is an effective method to image and track the distant dark targets by using the laser beam to illuminate them. The SNR of the laser range gated imaging system with range gating and non-range gating are analyzed. It is demonstrated that range gating greatly reduces the lights backscattered by aerosols. The key techniIt is an effective method to image and track the distant dark targets by using the laser beam to illuminate them. The SNR of the laser range gated imaging system with range gating and non-range gating are analyzed. It is demonstrated that range gating greatly reduces the lights backscattered by aerosols. The key techniques of the laser range gated imaging system are discussed The advantages and disadvantages of the conventional laser range gated imaging system are analyzed. An improved laser range gated imaging system based on DSP is proposed This system uses the fast DSP controller to accomplish range measurement and range delay and to provide several nanoseconds gated pulse to gate ICCD camera It overcomes some shortcomings of the conventional laser range gated imaging systems, such as need to know preset range delay and laser inner time delay. It can obtain the targets' range information and range-gated image..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 284 (2004)
Experimental Research of High-Sensitivity Detection of Methane
MA Wei-guang, YIN Wang-bao, DONG Lei, LI Chang-yong, and JIA Suo-tang
In this paper, the direct absorption spectrum of methane 2v3 band R(9) manifold near 1.637 mm was detected The minimum detectable absorbance of 1.4×10-3 was achieved, while the minimum detectable absorbencies of 5.2×10-4, 1.1×10-4, 4.0×10-4 were obtained by use of harmonic detection for respectivelyIn this paper, the direct absorption spectrum of methane 2v3 band R(9) manifold near 1.637 mm was detected The minimum detectable absorbance of 1.4×10-3 was achieved, while the minimum detectable absorbencies of 5.2×10-4, 1.1×10-4, 4.0×10-4 were obtained by use of harmonic detection for respectively in the condition of optimized modulation. There is a great improvement relative to the direct absorbance. Meanwhile the higher is the order of harmonic, the higher is the detection sensitivity..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 287 (2004)
Research of Measurement Instrmnent for Large -Scale Workpiece Diameter by Dual Frequency Laser Interferometer
MENG Zong, and ZHAO Xin-qiu
A new method of aiming and positioning the measured points of a large workplace by a laser beam and measuring the large distance accurately by a dual frequency laser interfe-rometer are presented in this paper. In this way ’the distance between centers of two quadrant silicon, hotodlades on the chucks can be mea-sured A new method of aiming and positioning the measured points of a large workplace by a laser beam and measuring the large distance accurately by a dual frequency laser interfe-rometer are presented in this paper. In this way ’the distance between centers of two quadrant silicon, hotodlades on the chucks can be mea-sured by a dual frequency laser interferometer. The dimension of the measured diameter can be calculated by a simple equation. The experiment results show that the relative measurement error is less than 5×10-6..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 290 (2004)
Experimental Research of Fabricating the Nanometric Optical Fiber Probes in Three Etching Methods
WANG Hui, REN Hong-Uang, LIN Tu-sheng, HE Jing-tian, LIANG Er-jun, MN Guang-feng, WANG Hui-hui, and LIU Yi
The three different etching methods, which are tube etching method, fusion splicing and fusion pulling etching method and chemical etching method were compared, and the excellent nanometric optical fiber probes were got which are used to make optical fiber nanobiosensors. The experimental principle, the condition and tThe three different etching methods, which are tube etching method, fusion splicing and fusion pulling etching method and chemical etching method were compared, and the excellent nanometric optical fiber probes were got which are used to make optical fiber nanobiosensors. The experimental principle, the condition and the experimental results of threeetching methods were presented in this paper..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 293 (2004)
Investigation on the Mechanism of Ultrashort Pulse Laser Interacting with Soft Tissues
LIU Li, and LI Zheng-jia
The mechanism of ultrashort laser interacting with biological tissues was investigated in detail and a model has been developed to calculate irradiance thresholds for laser induced optical breakdown in biological soft tissues. Calculation results show that for nanosecond or subnanosecond laser pulses, initial heating eThe mechanism of ultrashort laser interacting with biological tissues was investigated in detail and a model has been developed to calculate irradiance thresholds for laser induced optical breakdown in biological soft tissues. Calculation results show that for nanosecond or subnanosecond laser pulses, initial heating electrons in strongly absorbing media contribute significantly to avalanche ionization and optical breakdown threshold decreases with increasing tissue absorbance; for subpicosecond laser pulses, multiphoton ionization is the main mechanism for optical breakdown which is insensitive to linear absorption..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 296 (2004)
Application of KTP/YAG 532 nm and 660 nm Laser for Interposition Treatment
LI Zheng-jia, FAN Xiao-hong, LI Ying-chun, HE Yan-yan, JING Qiu-sheng, and Li Cai-ping
By doubling the frequency of two laser beams whose wavelength is 1064 nm and 1320 nm, 532 nm and 660 nm laser are obtained, separately. The fiber with 300 μm diameter is used to transfer those laser beams to body cavity for interposition treatment The result shows that KTP/YAG 532 run and 660 nm laser is better for intBy doubling the frequency of two laser beams whose wavelength is 1064 nm and 1320 nm, 532 nm and 660 nm laser are obtained, separately. The fiber with 300 μm diameter is used to transfer those laser beams to body cavity for interposition treatment The result shows that KTP/YAG 532 run and 660 nm laser is better for interposition treatment than the YAG 1064 nm and 1320 nm..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 299 (2004)
Using Low Energy Laser to Cure Bald and Study on its Interaction Mechanism
FAN Xiao-hong, LI Zheng-jia, LI Ying-chun, and HE Yan-yan
For the marked bio-effect of low energy laser on bio-tissue, with low energy laser irradiating patient's points focused laser can help to cure them. Low energy laser can help to speed blood circulation and cure the wound. Using LD with wave length between 600 rum and 800 nm to treat patient bald, a good effect was For the marked bio-effect of low energy laser on bio-tissue, with low energy laser irradiating patient's points focused laser can help to cure them. Low energy laser can help to speed blood circulation and cure the wound. Using LD with wave length between 600 rum and 800 nm to treat patient bald, a good effect was got..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 302 (2004)
Mechanism Analysis on Interaction between Green Laser and Molecule Bond on Intra-Vascular Laser Irradiation
ZHANG Can-bang, ZHOU Ling-yun, DAI Zhi-fu, and Liu Shu-xiao
The mechanism of the interaction between green laser and molecule bond of blood is analyzed by quantum mechanics. The effects of green laser and He-Ne laser on intra-vascular laser irradiation are compared when frequency ω0 changes. In a certain range as a result, green laser has the same clinical effect as He-Ne laserThe mechanism of the interaction between green laser and molecule bond of blood is analyzed by quantum mechanics. The effects of green laser and He-Ne laser on intra-vascular laser irradiation are compared when frequency ω0 changes. In a certain range as a result, green laser has the same clinical effect as He-Ne laser doea..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 305 (2004)
Fluorescence Detection for Biochips by Laser Confocal Scanning
WANG Li-qiang, NI Xu-xiang, LU Zu-kang, LI Ying-sheng, and ZHNEG Xu-feng
Scanning detection of biochip based on fluorescence labeling is introduced in the paper, the detection method can be divided into two category: one is confocal scanning detection method in which a photomultiplier tube is used as fluorescence sensor, the other is flood illumination of the entire biochip and uses CCD as Scanning detection of biochip based on fluorescence labeling is introduced in the paper, the detection method can be divided into two category: one is confocal scanning detection method in which a photomultiplier tube is used as fluorescence sensor, the other is flood illumination of the entire biochip and uses CCD as fluorescence sensor. A novel method of fluorescence detection for biochips is presented, which uses a 532 nm laser and 635nm laser to excite the fluorescent dyes according the principle of laser confocal scanning. The fluorescence emitted from cy3 and cyo is detected using a photomultiplier tube (PMT) sequentially. One dimension scanning of the biochips is performed by a telecentric f-θ objective with a moving coil optical scanner, the other dimension is scanned by a stepping motor driving the precision guidance. The experiment results state that the resolution of the presented technology is 5 μm, the signal-to-noise ratio can reach 10s and the detection limit is 1 fluor/μm2, and the cross-talk phenomenon is eliminated completely..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 307 (2004)
Observation on the Temperature Characteristic and the Effect of Laser Bleaching Discolored Teeth
ZHU Xiao, QI Li-jun, QIU Fu-sheng, SONG Ting-ting, YANG Yun-feng, TIAN Li-hua, and XIA Jian-guo
The temperature characteristic and the effect of laser bleaching discolored teeth are reported in this paper. The temperature characteristics of the discolored teeth without bleaching agent and with bleaching agent are researched. The temperature of laser bleaching is controlled at 46 ℃. Laser power bleaching discoloreThe temperature characteristic and the effect of laser bleaching discolored teeth are reported in this paper. The temperature characteristics of the discolored teeth without bleaching agent and with bleaching agent are researched. The temperature of laser bleaching is controlled at 46 ℃. Laser power bleaching discolored teeth is applied in clinic and the results are successful with the special bleaching gel containing 35WHz02 and 6% magnesium carbonate..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 310 (2004)
A Multicast Routing and Wavelength Assignment Algorithm Based on Equivalent Networks in WDM Optical Networks
QI Xiao-gang, and LIU San-yang
WDM network model with distinguishing feature of nodes' functions is described for the problem of routing and wavelength assignment, and the concepts of equivalent wavelength arc, equivalent wavelength networks and equivalent multicast tree are presented Based on this model and relevant routing and assignment of waWDM network model with distinguishing feature of nodes' functions is described for the problem of routing and wavelength assignment, and the concepts of equivalent wavelength arc, equivalent wavelength networks and equivalent multicast tree are presented Based on this model and relevant routing and assignment of wavelength (RAW) strategy, a multicast routing and wavelength assignment algorithni is put forward, which is a fast and effective algorithm. Finally, the algorithm's complexity, and point out the superiorities and drawbacks of the algorithm is analyzed.routing and wavelength assignment; multicast routing algorithm.
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 313 (2004)
Properties of 1×2 Polarizing Optical Splitter with Continuous Tunable Coupling Ratio
WANG Li-meng, ZHANG Ting-rong, CAO Wei-min, and ZHANG Jie-ming
The operating principle and character for optical splitter with polarization are analyzed by using tunable Faraday's rotator, the expression in ordinary and extraordinary light of coupling ratio of optical splitter are obtained, and the calculated curves for φF～D, φF～GR.(CRe),CE0(CRe)～D relation parameters are giveThe operating principle and character for optical splitter with polarization are analyzed by using tunable Faraday's rotator, the expression in ordinary and extraordinary light of coupling ratio of optical splitter are obtained, and the calculated curves for φF～D, φF～GR.(CRe),CE0(CRe)～D relation parameters are givea The precision adjusted for quantity of displacement can attain to μm order of magnitude when intensity of magnetic field H=79580 A/m. The coupling ratio to optical splitter will tune continuously in 0%~100% range, and it will be provided with two functions on splitting as well as attenuation..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 316 (2004)
Research on Very Short Reach Parallel Optical Modules
ZHOU Xin-jun, CAO Ming-cui, LUO Feng-guang, XU Jun, LUO Zhi-xiang, and YUAN Jing
This рrфеr describes the design of an OIF-approved 10 Gbps very short reach parallel optical modules, which comprises of high speed parallel optical transceiver and VLSI based interface circuit The structure of VCSEL based parallel optical transceiver, the coupling and packaging technology of high density fiber arrays This рrфеr describes the design of an OIF-approved 10 Gbps very short reach parallel optical modules, which comprises of high speed parallel optical transceiver and VLSI based interface circuit The structure of VCSEL based parallel optical transceiver, the coupling and packaging technology of high density fiber arrays are presented. The design of the interface circuit with complex programmable logic devices (CPLD) chip is also described..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 319 (2004)
Photoluminescence of Er Ion Implanted Al2O3 Waveguides Film
WANG Xing-jun, WANG Hui, CHEN Tao, and LEI Ming-kai
The Er3+-doped Al2O3 optical films have been prepared on the thermally oxidized SiO/Si (100) substrate by the Er ion implantation Al2O3 films, which were obtained by the sol-gel method with a clipping-coating technique, using the aluminium isopropoxide [Al(OC3H7)3]-derived ΑΙΑ sols. The phase structure, mixture of γ-(AThe Er3+-doped Al2O3 optical films have been prepared on the thermally oxidized SiO/Si (100) substrate by the Er ion implantation Al2O3 films, which were obtained by the sol-gel method with a clipping-coating technique, using the aluminium isopropoxide [Al(OC3H7)3]-derived ΑΙΑ sols. The phase structure, mixture of γ-(Al,Er)2O3 and θ-(Αl,Εr)2O3, was observed for the Er3+-doped Al2O3 films sintered at 900 V. The photoluminescence (PL) spectrum centered at 1.533 μm with the full width at half-maximum (FWHM) of 44 nm was observed for the Er3+-doped Al2O3 film with the Er ion implantation fluence of 4×1016 cm, which attributed to the intra-4f transition between the first excited (4I13/2) and the ground state (4I25/3) of Er3+. The PL intensity at 1.533 μm increased with increasing the Er ion implantation fluence from 0.2×1016 cm-2 to 4×1016 cm-2 for the Er3+-doped Al2O3 films sintered at 900 When the sintering temperature was increased to 1200 ℃, the PL intensity at 1.533 μm first increased, and then decreased with increasing the Er ion implantation fluence from 0.2×1016 cm-2 to 4×l016 cm-2..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 323 (2004)
Design of Laser Scanner System and the Analysis of Exposure Amount of the Image
HU Ju-guang, ZHANG Bai-gang, XU De-gang, WANG Peng, and YAO Jian-quan
The polygonal mirror-flat rotating-vibrating mirror laser scanner system is designed for PAL standard TV signal. The polygonal mirror has 40 facets and its rotating speed is ω=390.625 r/s. An analysis solution is obtained for horizontal scanning velocity of laser point on the screen. Based on the solution, it is found The polygonal mirror-flat rotating-vibrating mirror laser scanner system is designed for PAL standard TV signal. The polygonal mirror has 40 facets and its rotating speed is ω=390.625 r/s. An analysis solution is obtained for horizontal scanning velocity of laser point on the screen. Based on the solution, it is found that exposure amount at the beginning (or end) of horizontal scanning line is 97.7% of that at the middle time of 32 μs..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 326 (2004)
New Method of Laser Scratching to Determine the Bond Strength of the Film-Substrate Interface
FENG Ai-xin, ZHANG Yong-kang, XIE Hua-kun, ZHOU Ming, and CAI Lan
The bond strength of film-substrate interface is often the predominant factor and chiefly target in determining the performance and reliability of film-substrate system. A new method of infared and deep UV radiation laser scratch testing technique is presented in the article to determine the bond strength of film-substThe bond strength of film-substrate interface is often the predominant factor and chiefly target in determining the performance and reliability of film-substrate system. A new method of infared and deep UV radiation laser scratch testing technique is presented in the article to determine the bond strength of film-substrate interface. The laser scratching mechanism and diagnosis technology of the bonding state of the film-substrate interface are studied on the bases of analyzing the technological advantages of the laser scratching technique..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 329 (2004)
Investigation on Crater Morphology by High Repetitive Rate YAG Laser-Induced Discharge Texturing
LI Zheng-yang, and YANG Ming-jiang
When a high repetitive rate YAG laser pulse acts on a metal surface used as one of two electrodes, a plasma plume is produced, and a discharge occurs between the electrodes at a voltage far below breakdown threshold. So the discharge is controlled by the laser pulse. The metal surface is textured by a distribution of dWhen a high repetitive rate YAG laser pulse acts on a metal surface used as one of two electrodes, a plasma plume is produced, and a discharge occurs between the electrodes at a voltage far below breakdown threshold. So the discharge is controlled by the laser pulse. The metal surface is textured by a distribution of discharge craters. It is shown that the shape of discharge craters is determined by current waveform, electrical polarity and medium between electrodes. The relationship between diameter of craters and parameters of power supplier are investigated, especially for the three electrode materials, such as steel, iron and brass..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 332 (2004)
Laser-Induced Self-Propagating Reaction Synthesis of Zr-Ti-Ni Quasicrystal
WANG Сun-shan, WANG Yan-fang, Pan Xue-min, Gao Ya-li, and DONG Chuang
Noticing that strong exothermic reaction due to large negative enthalpy of mixing can occur among major components of the Zr-Ti-Ni quasicrystalline alloy systems, a new technique to fabricate quasicrystalline material using laser-induced self-propagating reaction synthesis (LSRS) is developed The LSRS for Zr-Ti-Ni alloNoticing that strong exothermic reaction due to large negative enthalpy of mixing can occur among major components of the Zr-Ti-Ni quasicrystalline alloy systems, a new technique to fabricate quasicrystalline material using laser-induced self-propagating reaction synthesis (LSRS) is developed The LSRS for Zr-Ti-Ni alloy system shows that the product is mainly composed of the quasicrystalline I - phase, the α (Ti/Zr) solid-solution and the Laves phase with MgZn2 structure type. However, the content of the I-phase in the products changes with the composition of the raw powder mixtures. When the composition of the raw powder mixtures changes from Zr44Ti40Ni16 to Τi40Ζr40Νi20 and the content of the I-phase decreases. The microhardness of the samples increases with the increase of the content of the I-phase..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 335 (2004)
Design of Control System and Resonator for High Power CO2 Laser
HE Chang-yu
The structural style of the resonator of HGL-20 type CW CO2 laser is investigated The roles of the external-bridge-intracavity structure and optical cavity micro-ac^ust system for improving the stability of the laser resonator are discussed. The design characteristics of the electrical supply measuring system, the optiThe structural style of the resonator of HGL-20 type CW CO2 laser is investigated The roles of the external-bridge-intracavity structure and optical cavity micro-ac^ust system for improving the stability of the laser resonator are discussed. The design characteristics of the electrical supply measuring system, the optical cavity and power measuring system, the vacuum measuring system, the auto gas filling-draining system, the temperature measuring system, the safety alarm system, etc., and the effect of these factors on the stability and the beam quality of the output laser are investigated..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 338 (2004)
A New Type of RF Supply for Medium Power RF CO2 Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
As the core technology, a new type of RF supply was developed and produced successfully. The high frequency supply transistor was used in the design, which made the new RF supply lower cost and more excellent performance. Further more,the impedance match network and supply modulation were discussed.As the core technology, a new type of RF supply was developed and produced successfully. The high frequency supply transistor was used in the design, which made the new RF supply lower cost and more excellent performance. Further more,the impedance match network and supply modulation were discussed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 341 (2004)
Principle of Controlling Laser Marking and an Embedded System Designed
YANG Yan-zhi, LI Jian-wu, WANG Sheng-Ue, ZHAO Xue-min, HE Yun-gui, WANG Xiao-dong, and YANG Hai
The principle of laser marking system is introduced, including controlling of the RF excited laser power and dual galvanometer scanning. An embedded system with PC/104 module is designed Its hardware form is presented in the article.The principle of laser marking system is introduced, including controlling of the RF excited laser power and dual galvanometer scanning. An embedded system with PC/104 module is designed Its hardware form is presented in the article..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 344 (2004)
A Sort of On-Line Laser Perforating System Based on Microcontroller
LI Jian-wu, YANG Yan-zi, WANG Sheng-lie, HE Yun-gui, ZHAO Xue-min, ZHANG Zhong-guo, LJ Dun-ming, and SU Ji-ping
About the application of laser perforating tipping paper, it emphasized to present the hardware and software structures of the system, and the former is composed of the light rout system based on polyhedral prism and the controlling system with closed loop feedback based on microcontroller. By measuring and analyzing tAbout the application of laser perforating tipping paper, it emphasized to present the hardware and software structures of the system, and the former is composed of the light rout system based on polyhedral prism and the controlling system with closed loop feedback based on microcontroller. By measuring and analyzing the degree of ventilation of perforated lipping paper, it proved that the system is reliable and practicable..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 347 (2004)
Investigation of Galvanometer Scanner Servo
YE Qiao, WANG Sheng-lie, ZHAO Xue-min, YANG Hai, HE Yun-gui, and SU Ji-ping
In this paper, the theory of galvanometer servo system is investigated, the system construction diagram is given, alternating position regulator is designed and the position following control system, which adopts closed-loop control, is completed. In the experiment, effectiveness of this system is satisfying.In this paper, the theory of galvanometer servo system is investigated, the system construction diagram is given, alternating position regulator is designed and the position following control system, which adopts closed-loop control, is completed. In the experiment, effectiveness of this system is satisfying..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 351 (2004)
Theoretical Analysis on Improving the Quality of Laser Drilling and Technique Optimization
ΒΙΑΝ Fei, and XIAO Ze-xin
The experiments for Q235-A steel using the Tianjin JG-2016 numerical control YAG laser processing machine showed that the laser working voltage, laser pulse frequency, laser pulse width and assistant gas pressure influence the round degree mostly among all the laser drilling parameters. Based on the mode of Grey relevaThe experiments for Q235-A steel using the Tianjin JG-2016 numerical control YAG laser processing machine showed that the laser working voltage, laser pulse frequency, laser pulse width and assistant gas pressure influence the round degree mostly among all the laser drilling parameters. Based on the mode of Grey relevant analysis in grey system theory, the rule relation among the laser drilling parameters which effected the round degree and conical degree was fomid, and a building up mixed mathematical models using grey system GM (1,N) model and neural network model was also proposed which can reflect the nonlinear and multi-coupling relationship of the laser drilling surface round degree, conical degree and laser drilling parameter. Thus the processing technology of the laser drilling can be optimized, so as to improve the qualities and reduce the round degree and axial conical degree error as well..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 355 (2004)
Measurement System of Multi-Channel Laser Power Waveform
ZHANG Zhi-xiang, WANG Qi-hong, BI Ji-jun, ZHOU Hua-zhen, and YANG Lin
This paper introduces a measurement system which measures the laser power waveforms from the multi-channel amplifier of SG-Π. By collecting laser power data at 26 places in SG-Π and transmitting the data to a data analyzing system via a computer network, the system provides real-time and effective sampling of laser wavThis paper introduces a measurement system which measures the laser power waveforms from the multi-channel amplifier of SG-Π. By collecting laser power data at 26 places in SG-Π and transmitting the data to a data analyzing system via a computer network, the system provides real-time and effective sampling of laser waveforms for the power balance project..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 359 (2004)
Ladar Image Noise Suppressing with Median Filter and Image Processing System Simulation
LI Qi, LI Zi-qin, WANG Yong-zhen, and WANG Qi
In the paper, noise suppressing in ladar image is analyzed with various windows of median filter. The speckle index is calculated in various conditions. Meanwhile, system simulation model on ladar image processing is programmed by Matlab. This image-processing model can be used in simulation system and actual ladar imaIn the paper, noise suppressing in ladar image is analyzed with various windows of median filter. The speckle index is calculated in various conditions. Meanwhile, system simulation model on ladar image processing is programmed by Matlab. This image-processing model can be used in simulation system and actual ladar image..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 362 (2004)
Study on the Self-Mixing Effect of the Semiconductor Laser Modulated by Triangular Current
GUI Hua-qiao, LU Liang, XIE Jian-ping, ZHAO Tian-peng, and MING Hai
A theoretical analysis on self-mixing effect of the semiconductor laser modulated by triangular current is presented by using a three-mirror cavity model and rate equations. The self-mixing signals are obtained by numerical simulation. Also, the characteristics of self-mixing effect are analyzed in detail. Good agreemeA theoretical analysis on self-mixing effect of the semiconductor laser modulated by triangular current is presented by using a three-mirror cavity model and rate equations. The self-mixing signals are obtained by numerical simulation. Also, the characteristics of self-mixing effect are analyzed in detail. Good agreement is found between the theoretical results and measurements using a semiconductor laser..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 365 (2004)
Study on Automatic Control Device of Powder Feeding for Laser Cladding
HE Chang-yu, and DENG Qian-song
The automatic control device of powder feeding for laser cladding integrates the special Z-type measuring path and the sensor into the powder feeder of scraper type. According to the powder flux variation and the program's request, it fulfils the aim to adjust the powder flux automatically by controlling the gap beThe automatic control device of powder feeding for laser cladding integrates the special Z-type measuring path and the sensor into the powder feeder of scraper type. According to the powder flux variation and the program's request, it fulfils the aim to adjust the powder flux automatically by controlling the gap between the powder-mouth and dial or by controlling the rotational speed of the dial, with the help of examining the powder flow signals in the path and analyzing the examined signals..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 368 (2004)
Measurement on Beam Quality of High-Performance COIL
GONG Fa-quan, ZHAO Tong, LIU Wan-fa, and JIN Yu-qi
The methods used for measuring beam quality and beam drift of high-performance chemical oxygen iodine laser (COIL) were introduced. The relation between measurement of beam quality and beam drift was anaiyzed and the valid data used for evaluating beam quality were given.The methods used for measuring beam quality and beam drift of high-performance chemical oxygen iodine laser (COIL) were introduced. The relation between measurement of beam quality and beam drift was anaiyzed and the valid data used for evaluating beam quality were given..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 371 (2004)
Performence Provement of the High Power KrF Laser and Its Application
SHAN Yu-sheng, XIANG Yi-huai, MA Jing-long, TANG Xiu-zhang, GONG Kun, LI Ye-jun, ZHANG Ji, MA Wei-yi, and WANG Nai-yan
A beam smoothing experiment of one beam of the 6-beams high power KrF laser system at CIAE has been demonstrated using the technigue of echelon-free induced spatial incoherence (EF-ISI). The focal profiles with 1.4% rms deviation from a flat top distribution through the laser system capable of producing 30-40 J per pulA beam smoothing experiment of one beam of the 6-beams high power KrF laser system at CIAE has been demonstrated using the technigue of echelon-free induced spatial incoherence (EF-ISI). The focal profiles with 1.4% rms deviation from a flat top distribution through the laser system capable of producing 30-40 J per pulse in 50 ns at a target were obtained and the 50 ns pulse has been compressed to 25 ns by keeping the same energy per pulse using an optical gain-saturation switch mediod. The flyer acceleration experiments by a high-power smoothing beam KrF laser with a long pulse duration have been made. The flyer consists of Kapton film and Al foil, it is accelerated to the velocity of over 8 km/s by a powr density of 7×1011 W/cm2 driving flyer with a focal spot diameter of 300 μm using KrF laser irradiation. The 1-D hydrodynamics simulation shows that the peak pressure caused by the impact of flyer is over IMbar in the impacted Cu targer. In addition to above experiments the supershort laser amplification through electron pumped preamplifier and main-amplifier and the measurements of super-hot electron temperature for the supershort laser beam interactron with target by a 1800 electron magneto-spectrometer have been conducted..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 373 (2004)
Study on Properties of Nd3+:KGd(WO4)2 Laser Crystal
TU Chao-yang, LI Jian-fu, YOU Zheng-yu, ZHU Zhao-jie, and WU Bai-chang
The crystal of Nd3+:KGd(WO4)2 with the size of φ20 mm×60 mm was grown by using the modified CZ. method The absorption and emission spectra in the directions of a,b and c axes were measured, the result shows that the intensity of absorption and emission spectra in the direction of a axis is the strongest Therefore,The crystal of Nd3+:KGd(WO4)2 with the size of φ20 mm×60 mm was grown by using the modified CZ. method The absorption and emission spectra in the directions of a,b and c axes were measured, the result shows that the intensity of absorption and emission spectra in the direction of a axis is the strongest Therefore, the direction of a axis is the most suitable for laser experiment The intracavity stimulated Raman scattering frequency self-conversion of the 1352.5 nm laser line was obtained under short-pulsed longitudinal pumping at 600 nm. The wavelength is eye-safe at 1539.5 nm and the conversion efficiency was 1.26%. A laser output of 125.5 mJ at 1.067 μm was obtained from the excitation of a Xe lamp. Compared with the YAG-Nd3+ laser crystal, which was performed the same laser experiment at the same conditions, NdhKGd (WO4)2 has the advantages of lower laser threshold and higher efficiency as well as the polarized laser output Therefore, it is expected that Nd3+:KGd(WO4)2 crystal will be very useful in the miniature laser..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 377 (2004)
Development of Research on Large-Sized Ti:Sapphire Laser Crystals
SI Ji-Uang, XU Jun, ZHAO Guang-jun, ZHOU Guo-qing, LI Hong-jun, WANG Jing-ya, and DENG Pei-zhen
The applications of Ti-doped sapphire (Т?rА?rОа) in femo-second ultra-fast and high-average-power laser system were described briefly. It is suggested that the growth of large-sized Ti:S^)phire with high optical properties is the key note in ultra fast and high power laser applications. The various growth methods of TiThe applications of Ti-doped sapphire (Т?rА?rОа) in femo-second ultra-fast and high-average-power laser system were described briefly. It is suggested that the growth of large-sized Ti:S^)phire with high optical properties is the key note in ultra fast and high power laser applications. The various growth methods of TiiAlA were reviewed, and the development of large-sized Тi:Аl2О3 with high quality is proponed in the end of this paper..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 381 (2004)
Analyses on Depolarization Losses of Plasma-Electrode Pockels Cell
ZHANG Xiong-jun, ZHENG Kui-xing, WU Deng-sheng, DONG Yun, ZHENG Jian-gang, and LU Jing-ping
By analyses and calculation of the depolarization loss of plasma-electrode Pockels cell (PEPC) caused by the disorientation and strain with or without half wave voltage, the demands of machining and fixing Pockels and the half wave voltage variation are given. The depolarization losses of PEPC under different angle of By analyses and calculation of the depolarization loss of plasma-electrode Pockels cell (PEPC) caused by the disorientation and strain with or without half wave voltage, the demands of machining and fixing Pockels and the half wave voltage variation are given. The depolarization losses of PEPC under different angle of the switching crystal optical axis and the beam propagating direction are measured The results are accord with the calculating results..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 384 (2004)
Suited Connection of the Optical Antenna and Photoconductive Surface on the Coherent Ladar
WANG Chun-hui, WANG Qi, and SHANG Tie-liang
The physical models of local laser and signal laser are plane wave-Airy spot model or Gauss wave-Aiiy spot model commonly in heterodyne laser radar optics. In the case of plane wave-Aiiy spot, the radius of the photosensitive plane should be 0.79 times of that of the diffraction limit speckle of the optical system, theThe physical models of local laser and signal laser are plane wave-Airy spot model or Gauss wave-Aiiy spot model commonly in heterodyne laser radar optics. In the case of plane wave-Aiiy spot, the radius of the photosensitive plane should be 0.79 times of that of the diffraction limit speckle of the optical system, the heterodyne efficiency is about 71% at this time. In the case of Gauss wave-Airy spot, the radius of the photosensitive plane should be 0.63 times of that of the diffraction limit speckle of the optical system and the heterodyne efficiency is about 81%..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 387 (2004)
Beam Shaping of Partially Coherent Light Beams
PU Ji-xiong, CAI Chao, and WU Feng-tie
In this paper, a partially coherent beam focused by a lens is investigated theoretically. It is shown that the focused intensity distribution in geometrical focus is not only dependent on the intensity distribution of the incident partially coherent beam, but also on the coherence. Based on this, a novel method is presIn this paper, a partially coherent beam focused by a lens is investigated theoretically. It is shown that the focused intensity distribution in geometrical focus is not only dependent on the intensity distribution of the incident partially coherent beam, but also on the coherence. Based on this, a novel method is presented for achieving partially coherent top-hat spot at the geometric focus by modulating the spectral degree of coherence of the incident partially coherent beam..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 390 (2004)
Analysis of the Effects of Gaussian Beam on Intersatellite Optical Communication
CHEN Yun-liang, MA Jing, TAN Li-ying, and WANG Qi
In order to evaluate the performances of the intersatellite optical communication (IOC), the beam vibration, transmitting loss and thermal noise should be analyzed In this paper, with the uniform analysis of beam spreading, random vibration, avalanche noise and thermal noise, the formula of sensitivity is given. And thIn order to evaluate the performances of the intersatellite optical communication (IOC), the beam vibration, transmitting loss and thermal noise should be analyzed In this paper, with the uniform analysis of beam spreading, random vibration, avalanche noise and thermal noise, the formula of sensitivity is given. And the laser transmitting factor (LTF) is introduced to describe the beam spreading and vibration· Utilizing the result, the effects of Gaussian beam on IOC are analyzed, and the means of the decision of system parameters are presented..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 393 (2004)
Experiment and Simulation Study on Hot-Image from Phase Scatterer
XIE Liang-ping, SU Jing-qin, WANG Wen-yi, JING Feng, and ZHAO Jian-ling
Nonlinear hot-image of phase scatterer in an intense laser beam is investigated nuinerically and experimentally. Light diffracted from a scatterer and the original beam in a nonlinear mediuin produce an interference pattern that creates a posiuve "lensing" effect It deflects some of the energy from the originNonlinear hot-image of phase scatterer in an intense laser beam is investigated nuinerically and experimentally. Light diffracted from a scatterer and the original beam in a nonlinear mediuin produce an interference pattern that creates a posiuve "lensing" effect It deflects some of the energy from the original beam into a downstream spot, which appears as a holographic image of the scatterer, called hot-image. The image is bright enough to damage expensive components located near it The measurements and calculations of the image in single element is reported. Good agreements are found between the experimental measurements and numerical simulations..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 396 (2004)
Platform Foundation Vibration Effects upon Pointing Stability of Laser Beam
CHEN Gui-min, JIA Jian-yuan, and FAN Guo-bin
In adverse circumstances such as mechanical vibration environment, it becomes a difficult technique problem to stabilize light-beam, which restricts the improvement of performance of optical systems. An analytical model of response of optical system's light-beam misalignment on platform ground vibration was establiIn adverse circumstances such as mechanical vibration environment, it becomes a difficult technique problem to stabilize light-beam, which restricts the improvement of performance of optical systems. An analytical model of response of optical system's light-beam misalignment on platform ground vibration was established based on matrix optics, vibration theory and finite element method. And a numerical simulation analysis of an optical system was given in detail. The results showed that to increase the damping coefficient of the platform structure could effectively stabilize light-beam. Using flexible sustained platform can decrease the relative misalignment, but the misalignment caused by the exciting vibration on the platform woula increase. Therefore, in adverse circumstances, the light-beam stability control is the key technique to improve the performance of optical system..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 399 (2004)
Experiments on B Integral Compensation Using Second-Order Cascaded Nonlinearity
CHEN Hao, ZHU He-yuan, Wang Tao, QIAN Lie-jia, and FAN Dian-yuan
It is a crucial problem in the field of high energy lasers to control Β integral (i.e. self-focusing) and to restrain it effectively. As conventional control techniques of Β integral (e.g. spatial filtering) nonetheless are far from solving the problem, novel techniques need to be developed. Based on nonlinear frequencIt is a crucial problem in the field of high energy lasers to control Β integral (i.e. self-focusing) and to restrain it effectively. As conventional control techniques of Β integral (e.g. spatial filtering) nonetheless are far from solving the problem, novel techniques need to be developed. Based on nonlinear frequency doubling the cascaded second order nonlinearity, virtually equivalent to the third order nonlinearity, has a controllable sign (allowing of negative values), variable values that can be veiy large, and can eliminate two-photon absorption. The cascade nonlinearity provides a new degree of freedom for short-pulse sources to produce serviceable nonlinear phase shifts. The preliminary experiments show that using these negative phase shifts can to a certain extent compensate for the cumulative Β integral due to the nonlinear propagation of high power laser (pulse) beams..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 403 (2004)
Focusing Properties of Cosh-Gaussian Beams
PENG Run-wu
Using the generalized Huygens-Fresnel diffraction integral, the propagation expression of Cosh-Gaussian (ChG) beams passing through a thin lens is derived The focused intensity distributions and dependence of focal shift upon decentered parameter and Fresnel number are analyzed. It is found that optimal focusing of ChGUsing the generalized Huygens-Fresnel diffraction integral, the propagation expression of Cosh-Gaussian (ChG) beams passing through a thin lens is derived The focused intensity distributions and dependence of focal shift upon decentered parameter and Fresnel number are analyzed. It is found that optimal focusing of ChG beams is achieved when the decentered parameter is appropriate value..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 406 (2004)
Fiber Optics Applied to Beams Automatic Alignment System
LIU Dai-zhong, CHEN Qin-hao, XU Ren-fang, and FAN Dian-yuan
The laser beams automatic alignment system is acyusting to adjust beam lines accurately in the high power laser facility for inertiai confinement fusion. Considering the requirements on alignment time and alignment precision of the SG-III prototype facility, using techniques on image fiber and transmission fiber, combiThe laser beams automatic alignment system is acyusting to adjust beam lines accurately in the high power laser facility for inertiai confinement fusion. Considering the requirements on alignment time and alignment precision of the SG-III prototype facility, using techniques on image fiber and transmission fiber, combining the image relaying principle of near field and far field, innovating in cavity mirror adljustment by using inserted fiber light source, utilizing the characteristic of image relaying in four-pass amplifiers, a reasonable and optimized scheme for automatic aligning four-pass beam paths is presented It has been demonstrated on the simulation experiment system of the SG-III prototype facility. Results indicate that beam paths acyustment can be finished in 15 minutes by the automatic alignment system. The precision of the near field acUustment was less than 0.5% of the spot The accuracy of the far field adljustment was less than 0.3". Requirements of the SG-III prototype facility are met..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 409 (2004)
Study to Get High Frequency Scanning Using Galvanometer Optical Scanner
CHENG Xiang-yang, WANG Qi, and ZHANG Ning-bo
Optical scanner is often used to scan through certain angel at certain frequency; but a galvanometer optical scanner can scan at higher frequency with smaller angle. This paper uses the second order of differential equation for damped oscillation describing the dynamic characteristic of galvanometer, analyzing the tranOptical scanner is often used to scan through certain angel at certain frequency; but a galvanometer optical scanner can scan at higher frequency with smaller angle. This paper uses the second order of differential equation for damped oscillation describing the dynamic characteristic of galvanometer, analyzing the transfer function of galvanometer scanner under a harmonic driver force. The solution indicates that the scanning under harmonic drive is still a harmonic oscillation at the same frequency. The reciprocal square of scanning angle can be expressed as a function of frequency square. Measured the scanning angle under a certain frequency, accordingly providing a reference to achieve high frequency scanning. Basing on the above result of analysis and experiment, bring forward a design idea of smaller scanning reflector to fit smaller angle scanning, and carrying on experiment to prove the feasibility..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 412 (2004)
Experimental Study on Improving Beam Quality of MOPA System
WANG Zhi-tong
A master oscillator power amplifier (ΜΟΡΑ) system was designed, SBS phase-conjugate mirror was used in the system, the seeder was a narrow-linewidth laser of twisted mode with Cr4+:YAG as passive Q-Switch, two amplifiers were used to pass twice, image-relay telescope and 900 rotator was used to compensate the depolarizA master oscillator power amplifier (ΜΟΡΑ) system was designed, SBS phase-conjugate mirror was used in the system, the seeder was a narrow-linewidth laser of twisted mode with Cr4+:YAG as passive Q-Switch, two amplifiers were used to pass twice, image-relay telescope and 900 rotator was used to compensate the depolarization bewteen amplifiers, three liquids of CCl4. FYeonll2 and CS2 were used in phase-conjugate mirror, SBS reflective rate and SBS fidelity were measured..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 415 (2004)
Beam Tracking Technology in Intersatellite Optical Communications
YU Si-yuan, MA Jing, TAN Li-ying, HAN Qi-qi, and CHEN Yun-liang
Two terminals in intersatellite optical communications (IOC) track each other, the tracking errors should be joint random variables in time and statistics. The influences of the tracking errors on the optical receiving are analyzed, and the stability state condition is estimated At last, for on-off keying modulation anTwo terminals in intersatellite optical communications (IOC) track each other, the tracking errors should be joint random variables in time and statistics. The influences of the tracking errors on the optical receiving are analyzed, and the stability state condition is estimated At last, for on-off keying modulation and direct detection in IOC, the influences of the tracking errors on the optical communication are simulated..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 418 (2004)
Application of Deformable Mirror in Spectral Phase Compensation of Femtosecond Laser
PENG Han-lin, TANG Bin, LENG Yu-xin, LIN Li-huang, and LI Ru-xin
A set of measure and compensation system is built up using a deformable mirror and a spectral phase interferometry for direct electric-field reconstruction (SPIDER) instrument in a kHz Ti:S femtosecond laser. The experiment result shows that the spectral phase aberration of the laser is compensated well, and it is a siA set of measure and compensation system is built up using a deformable mirror and a spectral phase interferometry for direct electric-field reconstruction (SPIDER) instrument in a kHz Ti:S femtosecond laser. The experiment result shows that the spectral phase aberration of the laser is compensated well, and it is a simple and efficient method in adaptive optics using the deformable mirror to compensate the spectral phase aberration..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 421 (2004)
Study on the Models of Multi-Pass Amplification of Nanosecond Light Pulse
WANG Wen-yi, SU Jing-qin, JING Feng, WANG Xiao, LUO Bin, ZHU Qi-hua, and PENG Zhi-tao
During the study on the multi-pass amplification of nanosecond light pulse, analytical results of Lowdermilk et al just care about two critical situations, namely, gain full-recovery and gain non-recovery. In fact, the gain recovery of amplifier during the pulse interval is most likely between those two recovery situatDuring the study on the multi-pass amplification of nanosecond light pulse, analytical results of Lowdermilk et al just care about two critical situations, namely, gain full-recovery and gain non-recovery. In fact, the gain recovery of amplifier during the pulse interval is most likely between those two recovery situations. In this paper, the equations about relationship between pulse fluence and population in the upper and lower energy level have been built up. Moreover, sequential relationship was deduced between time intervals during which light pulse interacts with population density in the upper and lower energy levels. Thus, the problem of gain non-recovery has been solved Moreover, the results calculated by this model were compared with those of Lowdermilk analysis model and multi-pass amplification experiment It was also analyzed that how the decay effect influenced on the characteristics of energy amplification· And relatively good and reliable results were achieved..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 424 (2004)
Impact of Coupled Motion of the Optical Communication Terminal and the Satellite Platform on Coarse Pointing
HAN Qi-qi, MA Jing, YU Si-yuan, and WANG Qi
In this paper, the coupled motion of optical communication terminal and the satellite platform and its impact on the error of coarse pointing are studied The influence of the coupled motion on the distribution of the beacon optical filed is also analyzed When the moment of inertia of satellite platform is less than 100In this paper, the coupled motion of optical communication terminal and the satellite platform and its impact on the error of coarse pointing are studied The influence of the coupled motion on the distribution of the beacon optical filed is also analyzed When the moment of inertia of satellite platform is less than 100 kg-m2, the coupled motion induced beacon pointing error will reduce the received optical power and system redundancy greatly. Compensation processing must be required in this condition. When the moment of inertia of satellite platform is between 100 kg·m2 and 1000 kg·m2, the coupled motion induced beacon pointing error becomes less. Compensation processing must be used when the pointing angle is bigger. When the moment of inertia of satellite platform is more than 10000 kg·m2, the pointing error could be neglected..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 427 (2004)
Platform for Laser Induced Damage Threshold Test of Optical Elements
YANG Jin-xing, ZHUANG Yi-fei, GAO Qi, and LIN Zun-qi
A platform for laser (1064 nm and 355 nm) induced damage threshold test of optical elements have been established. According to the international standard "ISO/DIS 11254-1.2” adopted, one shot on each unexposed site on the sample surface (1-on-l) and a new method of laser induced damage probability have been adoptA platform for laser (1064 nm and 355 nm) induced damage threshold test of optical elements have been established. According to the international standard "ISO/DIS 11254-1.2” adopted, one shot on each unexposed site on the sample surface (1-on-l) and a new method of laser induced damage probability have been adopted. The laser induced damage threshold test accuracy has been increased by using a effective area test system in platform..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 430 (2004)
Design of High-Accuracy Laser and Infrared Ray Interference Material Test System
LAN Yong, DAI Sui-an, SHEN Xi, and LIU Ju
The high-accuracy laser and infrared ray interference material test system are designed to overcome the thermal image system's shortcoming of low resolution of temperature. The light sources of the test system are 1.06 μm wavelength LD and 3-5 μm and 8-12 μm wavelength infrared radiation plate and it is modulated wThe high-accuracy laser and infrared ray interference material test system are designed to overcome the thermal image system's shortcoming of low resolution of temperature. The light sources of the test system are 1.06 μm wavelength LD and 3-5 μm and 8-12 μm wavelength infrared radiation plate and it is modulated with a 12 Hz mechanical chopper. The sensors are PIN and pyroelectricity sensors with optical filter. The optical receiver system is a 0178 mm Cassegarain optical system. The software is programmed in NI measurement studio, and some digital signal processing method like FIR band-pass filter and AR power spectrum are used to process the optical signal. This system's resolution is better than 0.5% and its accuracy is better than This system also supplies a complete experimental data analysis and statistic functions..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 434 (2004)
Characteristics of Near-Stoichiometric MgO-Doped Lithium Niobate
CHEN Ya-hui, YAO Jiang-hong, YAN Bo-xia, DENG Hao-liang, KONG Yong-fa, XU Jing-jun, and ZHANG Guang-yin
Lithium niobate crystals with different MgO-doped concentrations were processed by vapor transport equilibration technique and the composition Xc ([Li]/[Li+Nb]) of the prepared crystals was found to be 49.9 mol.%. A blue shift from 320 to 306 nm for processed crystals was found and the processed crystals doped 2 mol.% Lithium niobate crystals with different MgO-doped concentrations were processed by vapor transport equilibration technique and the composition Xc ([Li]/[Li+Nb]) of the prepared crystals was found to be 49.9 mol.%. A blue shift from 320 to 306 nm for processed crystals was found and the processed crystals doped 2 mol.% MgO increased the photorefractive damage resistance by at least 4 orders of magnitude compared with congruent crystal. By applying an external electric field of 3.5 kV/min, a periodically poled domain structure was obtained in the doped MgO (2mol.%) near-stoichiomerit LiNbO3 crystals..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 437 (2004)
Nb:KTP Bulk Crystal and It's Blue Lasers
LIU Wen, SHEN Hong-yuan, SHI Hong-sheng, ZHANG Guo-fang, and ZHANG ge
The Nb:KTP crystal was grown from the raw material containing different concentrations Nbjj06 by top-seed flux method in improved Ke melt The largest one weight 60 grams and the transparent area is 15 mm×l7 mm×14 mm dimension. Their transmission are more than 85% at the applied wave range. The cut-off wavelenThe Nb:KTP crystal was grown from the raw material containing different concentrations Nbjj06 by top-seed flux method in improved Ke melt The largest one weight 60 grams and the transparent area is 15 mm×l7 mm×14 mm dimension. Their transmission are more than 85% at the applied wave range. The cut-off wavelength has blue-shifted to 937 nm.The 468.5 nm and 473 nm as well as 480 nm blue lasers were obtained by different Nb doped KTP crystals. The principle refractive indices of 7.5 mol.-% Nb:KTP were measured The angle, temperature and spectral acceptance bandwidth were calculated for the crystal and then compared those with KTP and KNbO3. The results show that they are 2.6, 24 and 3.4 times those of KNbO3 crystal. Therefore, the applied condition will be relaxed and the frequency doubled performance will be improved..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 440 (2004)
Photoluminescence Characterization of Vertically Stacked InAs Quantum Dots
LI Shu-wei, and Koike Kazutcr
The epilayer of vertically stacked, self-assembled InAs Quantum Dots (QDs) was grown by MBE with solid sources in non-cracking K-cells. An attractive feature of vertically stacked InAs^AlGaAs quantum dots, which were buriea in AlGaAs high potential barrier and spacer epilayer, exhibits an unknown macroscopic quantum phThe epilayer of vertically stacked, self-assembled InAs Quantum Dots (QDs) was grown by MBE with solid sources in non-cracking K-cells. An attractive feature of vertically stacked InAs^AlGaAs quantum dots, which were buriea in AlGaAs high potential barrier and spacer epilayer, exhibits an unknown macroscopic quantum phenomenoa In the vertically aligned QDs, due to many-body effect and quantum-mechanical renormalization, the electron ground state splits into series of peaks of wruch the intensity gradually, systematically decreases to redshift direction with a wavelength constant Photoluminescence (PL) of quantum dots embedded in high potential barriers is studied as functions of barrier thickness and temperature. With the increase of barrier thickness, both of strengthened two-dimensional electron gas (2DEG) structure and strongly localized electron wave functions can increase the carrier recombination-The PL recombination characteristic of the samples with the barriers adjacent to a Si-doping GaAs layer is different from that of samples with barrier ac^acent to an i-GaAs layer..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 443 (2004)
Study on Growth and Heat Treatment of Yb3+ Doped Yttrium Aluminum Garnet Crystals
WANG Yong-guo, XU Xue-zheng, CHANG Mi, ZHU Jian-hui, MO Xiao-gang, and GUI You-xi
Growth and heat treatment of the yttrium aluminum garnet crystal doped with Yb3+ (Yb:YAG) were studied, and the suitable conditions for its heat field system, growth procedure and annealing conditions were found out dependently. Through the determination of transmission ratio of the crystal at 939 nm wavelength, the reGrowth and heat treatment of the yttrium aluminum garnet crystal doped with Yb3+ (Yb:YAG) were studied, and the suitable conditions for its heat field system, growth procedure and annealing conditions were found out dependently. Through the determination of transmission ratio of the crystal at 939 nm wavelength, the relation between the absorb coefficient of the crystal and the initial concentration of Yb in melt is calculated The transition efficiency of optical-to-optical of the crystal is 38.6%, with slope efficiency 55.1%. Heat bonding between Yb:YAG and undoped YAG crystal, and between Νd:YAG and undoped YAG crystal were investigated, and the satisfactory results were attained..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 447 (2004)
Study on Growth of Large-Size Nd:YLF Crystal by Czochralski Method
SHU Jun, MA Xiao-ming, WANG Yong-guo, XU Xue-zhen, and GUI You-xi
The large-size NcLYLF crystals were grown by Czochralski method The suitable conditions for heat field system and growth procedure were founded During the growth of Nd:YLF crystal, the pollution of water and oxygen on melt were overcome. NdiYLF crystal boules in 25-30 mm diameter, 100-120 mm long were grown. Laser rodsThe large-size NcLYLF crystals were grown by Czochralski method The suitable conditions for heat field system and growth procedure were founded During the growth of Nd:YLF crystal, the pollution of water and oxygen on melt were overcome. NdiYLF crystal boules in 25-30 mm diameter, 100-120 mm long were grown. Laser rods in 10 mm diameter, 100 mm long were cut out Laser rods with good optical homogeneity, no cracks, bubbles and scatters can be obtained..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 450 (2004)
Growth and Spectral Performance of YbAG and Highly Doped Yb:YAG
XU Xiao-dong, ZHAO Zhi-wei, ZHOU Guo-qing, DENG Pei-zhen, and XU Jun
Yb3Al5O12 and highly doped Yb:YAG (50 at.-%) crystals were successfully grown using Czochralski methoa. X-ray powder diffraction (XRPD) experiments showed that YbAG and highly doped Yb:YAG crystals had the same structure as Yb3Al6O12 (YAG) crystal. The absorption, emission spectra and fluorescence lifetime of YbAG and Yb3Al5O12 and highly doped Yb:YAG (50 at.-%) crystals were successfully grown using Czochralski methoa. X-ray powder diffraction (XRPD) experiments showed that YbAG and highly doped Yb:YAG crystals had the same structure as Yb3Al6O12 (YAG) crystal. The absorption, emission spectra and fluorescence lifetime of YbAG and highly doped Yb:YAG crystals at room temperature have also been studied, and spectral parameters have been compared with low doping Yb:YAG crystal. The results indicate that YbAG and highly doped Yb:YAG crystals are promising laser materials for high power laser output..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 456 (2004)
Effect of Thermal Treatment on Photoluminescence of Er-Doped Silicon-Rich SiO2 Prepared by Ion Implantion
ZHANG Chang-sheng, XIAO Hai-bo, LIN Zhi-lang, and ZHANG Feng
Er-doped silicon-rich Si, were prepared by ion implantation; Silicon nanocrystals, which enwrapped by amorphous Si, were observed when the implanted films were annealed above 900 ℃. The efficiency of PL at 1.54 μm and the microsteucture of the metarial are effected greatly by thermal treatment Er ions lie in amorphous Er-doped silicon-rich Si, were prepared by ion implantation; Silicon nanocrystals, which enwrapped by amorphous Si, were observed when the implanted films were annealed above 900 ℃. The efficiency of PL at 1.54 μm and the microsteucture of the metarial are effected greatly by thermal treatment Er ions lie in amorphous Si and couple with nc-Si through a-Si. The excitation energy from nc-Si to Er was shared by a-Si; At T>150 K, energy back transfer between excited Er and a-Si decreased the PL efficiency. The sample annealed at 1100 ℃ has a rather good emission efficiency..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 459 (2004)
Spectra Properties of U:CaF2 Crystal as Passive Q-Switch at 1.54 μm
SU Liang-bi, XU Jun, DONG Yong-jun, YANG Wei-qiao, ZHOU Guo-qing, and ZHAO Zhi-wei
U:CaF2 crystals, which can be used as passive Q-switch at 1.54 μm, were successfully grown by TGT with uranyl nitrate, calcium fluoride and lead fluoride as raw materials. The distribution coefficient of uranium in CaF2 is equal to 0.53, which was calculated through determining concentrations of U in various parts of UU:CaF2 crystals, which can be used as passive Q-switch at 1.54 μm, were successfully grown by TGT with uranyl nitrate, calcium fluoride and lead fluoride as raw materials. The distribution coefficient of uranium in CaF2 is equal to 0.53, which was calculated through determining concentrations of U in various parts of U:CaF2 single crystals by ICP-MS. Through changing the proportions of raw materials, uranium ions with various valences in CaF2 crystals were produced As-grown crystal without PbF2 is U4+:CaFa while the crystal grown in the presence of PbFz is U3+:CaF2, even U2+:CaF2 in the periphery near the graphite crucible. It is indicated that PbF2 could regulate the valences of uranium ions..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 462 (2004)
Effect of Substrate Temperature on the Structure of Crystallization and Transfer Rate of ZnO Thin Film
PAN Zhi-feng, YUAN Yi-fang, and KONG Fan-zhi
The substrate temperature is an important factor which affect the character of ZnO thin film and to a great extend, it can change the structure of crystallization of the thin film. The temperature can directly affect the transfer rate of the surface atom of the substrate, reraporize and crystallization. Under the indooThe substrate temperature is an important factor which affect the character of ZnO thin film and to a great extend, it can change the structure of crystallization of the thin film. The temperature can directly affect the transfer rate of the surface atom of the substrate, reraporize and crystallization. Under the indoor temperature, the XRD curve of the ZnO thin film was measured which grow in the different temperature and the best substrate temperature for the best quality of crystallization was probed From the temperature curve of the transfer rate, the same result was also got..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 462 (2004)
Er3+-Doped Al2O3/SiO2/Si Optical Waveguide Films Prepared by the Sol-gel Method
WANG Xing-jun, YANG Tao, and LEI Ming-kai
The Er3+-doped Al2O3 optical films have been prepared on thermally oxidized SiO2/Si(100) substrate by the sol-gel method with the dip-coating process, using the aluminium isopropoxide [Al(ОС3Н7)2]-derived Аl2О3 sols with the addition of erbium nitrate [Er(NO3)2·5H2O]. The surface morphology, thickness and structurThe Er3+-doped Al2O3 optical films have been prepared on thermally oxidized SiO2/Si(100) substrate by the sol-gel method with the dip-coating process, using the aluminium isopropoxide [Al(ОС3Н7)2]-derived Аl2О3 sols with the addition of erbium nitrate [Er(NO3)2·5H2O]. The surface morphology, thickness and structure of the Еr3+-doped Al2O3 films have been analyzed by the scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffractometer (XRD). The even, smooth and compact surfaces of Еr3+-doped Al2O3 films were obtained The ciystal size of 50~200 nm was observed for the Er3+-doped Al2O3 films. The thickness of the 1 mol% Er3+-doped Al2O3 film for 9 layers sintered at 900 ℃ is about 1.2 μm under a constant withdrawn rate of 100 mm/min. The phase structure, mixture of γ-Аl2O3 and θ-Аl2О3 was observed for undoped Al2O3 film. The thin film exhibited (110) and (120) preferred orientation for γ-Al2O3 and θ-Αl2O3 phase, respectively. The addition of 1 mol-% Er3+ has slight influence on the phase structure and preferred orientation of Al2O3 film. The photoluminescence (PL) spectra of 0.1 mol-%~1.5 mol% Er3+-doped Al2O3 films were detected at the measurement temperature of 10 Κ The PL peak intensity at 1.533 μm decreased with the increase of the Er3+ doping concentration· The corresponding full width at half maximum decreased from 45 nm to 36 nm..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 465 (2004)
Study of Broadband Antireflective Coatings for High Power Lasers
LV Hai-bing, WEI Yun, JIANG Xiao-dong, HUAN Zu-xin, and LI Ke
A two-layer broadband antireflective (AR) film by sol-gel dip-coating process on K9 substrate for high power lasers was investigated which consists of a layer of methyl silicone polymer overcoated with porous silica The performance of two-layer film was changed little by dip and spin coating.The experimental result shoA two-layer broadband antireflective (AR) film by sol-gel dip-coating process on K9 substrate for high power lasers was investigated which consists of a layer of methyl silicone polymer overcoated with porous silica The performance of two-layer film was changed little by dip and spin coating.The experimental result showed, when the physical thicknesses of silicone film and SiO2 AR film were suited and seemly, the two-layer AR film can be developed with transmission greater than 98% at the waveband range from 400 to 900 nm, of which damage threshold was over 20 J/cm2( 1064 nm, 4 ns)..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 468 (2004)
Study on Optimum Output Coupling of Unidirectional Non-Planar Ring Laser
SUN Wen-feng, YANG Su-hui, LI Lei, and ZHAO Chang-ming
The influences for S and Ρ polarization of the output surface of unidirectional non-planar ring laser on single frequency operation and output power are studied. For given crystal size, magnetic field and pumping power, the optimum output coupling of 5 and Ρ polarization have been calculated.The influences for S and Ρ polarization of the output surface of unidirectional non-planar ring laser on single frequency operation and output power are studied. For given crystal size, magnetic field and pumping power, the optimum output coupling of 5 and Ρ polarization have been calculated..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 471 (2004)
Thin-Film Enhanced Goos-H(a)nchen Shift
LI Chun-fang, YANG Xiao-yan, and ZHANG Ji-yue
The Goos-Hanchen (GH) shift that occurs in single-interface reflection and the frustrate-total-internal reflection is only of the order of the wavelength. The smallness of the shift for optical wavelength impedes its direct measurement in experiments. In this paper, the resonance-enhanced GH shift is investigated for tThe Goos-Hanchen (GH) shift that occurs in single-interface reflection and the frustrate-total-internal reflection is only of the order of the wavelength. The smallness of the shift for optical wavelength impedes its direct measurement in experiments. In this paper, the resonance-enhanced GH shift is investigated for totally reflected light beam from a thin-film coated prism at incidence angle less than, but close to the critical angle between the prism-film interfaces. It is shows that the GH shift oscillates with respect to the thickness of the thin film. Its maxima are approximately proportional to the thickness of the thin film, and the magnitude of the shift can be enhanced by a factor of 102~103 in comparison with the usual one. The GH shift can be modulated by changing the angle of incidence or the thickness of the thin film. Finally, the thickness of the film is required to satisfy a condition that is necessary to retain beam's profile in total reflection..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 474 (2004)
Laser Damage Properties of Polarizers Coatings at 1064 nm
HU Jian-ping, MA Ping, XU Qiao, ZHANG Wen-hui, and DUAN Li-hua
The laser induced damage of polarizer has been studied by use of 1064 nm laser with 10 ns pulse duration at the incident angle of 0° and 56°. The experiment results show that the damage morphology is scald and delamination for polarizer coating without SiO2 overcoat and with SiO2 overcoat when laser incident The laser induced damage of polarizer has been studied by use of 1064 nm laser with 10 ns pulse duration at the incident angle of 0° and 56°. The experiment results show that the damage morphology is scald and delamination for polarizer coating without SiO2 overcoat and with SiO2 overcoat when laser incident at angle 0° and 56° for S polarization light For Ρ polarization light, the damage of polarizer with SiO2 overcoat is mainly pits about 30~50 μm in size caused by polishing powder, and the pit size is almost independent on the energy density of the incident laser..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 477 (2004)
Stress Study of CVD Sulfur Doped Diamond Thin Films
ZHAO Qing-xun, WANG Yong-jie, NAN Jing-yu, YANG Jing-fa, and YAN Zheng
Sulfur doped diamond thin films have been synthesized via glow plasma assisted hot filament chemical vapor deposition (GP-CVD) using gas mixtures of methane, hydrogen, Argon and hydrogen sulfide. The stresses of the films have been studied as a function of the volume ratio of hydrogen sulfide (HzS) to methane (CH4) RSCSulfur doped diamond thin films have been synthesized via glow plasma assisted hot filament chemical vapor deposition (GP-CVD) using gas mixtures of methane, hydrogen, Argon and hydrogen sulfide. The stresses of the films have been studied as a function of the volume ratio of hydrogen sulfide (HzS) to methane (CH4) RSC the results show that with the increase of RSC, the total stress and intrinsic stress decrease. The total stress has the maximum 23 GPa when RSX is 4200 ppm; the intrinsic stress can balance the thermal stress and the total stress has the minimal absolute value when RSc is 6500 ppm, so the diamond thin films have good adherence on the substrates, it is good for the stabilization of the diamond growth. It can be concluded that the tensile stress and the compressive stress are mainly caused by high density of grain boundaries and impurities of sp2 carbon respectively..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 480 (2004)
Investigation of External-Cavity Semiconductor-Laser Emitting Near-Diffraction Limited Beam
LIU Chong, GE Jian-hong, CHEN Jun, Andreas Hermerschmidt, and H. J. Eichler
A novelty external-cavity is designed to improve beam quality aim at broad area laser diode (BALD). The external-cavity is composed with р?але mirror and blazed diffraction grating. With this kind of setup, a laser beam is obtained with 0.53° far field divergence angle, which corresponding to 1.3 times the diffracA novelty external-cavity is designed to improve beam quality aim at broad area laser diode (BALD). The external-cavity is composed with р?але mirror and blazed diffraction grating. With this kind of setup, a laser beam is obtained with 0.53° far field divergence angle, which corresponding to 1.3 times the diffraction limit, 320 mW output power, spectral line width of 0.02 nm when drive current is 2.7 times threshold current..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 483 (2004)
Influence of Length Misadjustment of Ring-Down Cavity on Its Output Power
YI Heng-yu, Peng Yong, HU Xiao-yang, LIU Sheng-lin, TIAN Xiao-qiang, and LV Bai-da
The cavity ring-down spectroscopy is a kind of measuring reflectivity technique. According to propagation equation of Gaussian beam and metrical principle of cavity ring-down, the theory model is set up for reflectivity measure with influence of length misadjustment Based on this model, it is numerically simulated thatThe cavity ring-down spectroscopy is a kind of measuring reflectivity technique. According to propagation equation of Gaussian beam and metrical principle of cavity ring-down, the theory model is set up for reflectivity measure with influence of length misadjustment Based on this model, it is numerically simulated that influence of length misacUustment of ring-down cavity on its output signal. The results show the excellent agreement between simulation and experiment, and prove that the theory model is accurate..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 486 (2004)
Investigation of the Multilayer Water-Cooling Si Mirror Used in High Power Laser
YU Wen-feng, CHENG Zu-hai, SUN Feng, ZHOU Ci-ming, and ZHANG Yao-ning
A three branch multilayer water cooled Si mirror is designed, which has a spiraiity shape. The characteristics of multilayer composite water-cooled Si mirror are simulated by ANSYS program and studied by experiments. When the flow rate is 1.6 m/s, the water pressure is 1.5×105 Pa, the net absorbed heat is 100 W, tA three branch multilayer water cooled Si mirror is designed, which has a spiraiity shape. The characteristics of multilayer composite water-cooled Si mirror are simulated by ANSYS program and studied by experiments. When the flow rate is 1.6 m/s, the water pressure is 1.5×105 Pa, the net absorbed heat is 100 W, the diameter is 80 mm, the largest deform is 0.186 μm The features of cooling process without heating cuased by laser radiation is that the decreasing deform is 0.063 μm in 0.75 s and the deform is 0.038 μm in 10.5 s. The multilayer water-cooled mirror performs well and can be used in high power laser..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 489 (2004)
Characteristics of Thermal Distortions of Optical Substrate Surfaces Subject to Irradiation of Chemical Oxygen-Iodine Laser
PENG Yu-feng, CHENG Zu-hai, SHENG Zhao-xia, YU Wen-feng, ZHANG Hu, and ZHOU Ci-ming
Temperature distributions and thermal deformations of silicon, sapphire, and calcium fluoride window substrates at 1.315 μm are calculated in terms of Green-function methods. The calculated results show that under conditions of irradiating of 10 kW intense laser with Gaussian shape, the maximum temperature rise in Al2OTemperature distributions and thermal deformations of silicon, sapphire, and calcium fluoride window substrates at 1.315 μm are calculated in terms of Green-function methods. The calculated results show that under conditions of irradiating of 10 kW intense laser with Gaussian shape, the maximum temperature rise in Al2O3, CaF2, Si, and SiO2 substrates is 5.6 ℃, 6.0 ℃, 35.1 ℃, and 26.6 ℃, respectively. The amount of thermal distortions in Аl2O3, CaF2, Si, and SiO2 substrates is 0.28 μm, 0.99 μm, 0.40 μm, and 0.14 μm, respectively..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 492 (2004)
Testing the Depth of Phase Grating by Optical Power Spectrum
Cao Xiang-qun, Lian Hua, and LI He-li
Acording to Fourier optics, when a plane wave through a grating,the angle of different order and relative intensity are decided by the grating, many information of gratings can be deduced from its diffraction power spectrum. A new method using power spectrum of different orders to measure depth of phase gratings.three Acording to Fourier optics, when a plane wave through a grating,the angle of different order and relative intensity are decided by the grating, many information of gratings can be deduced from its diffraction power spectrum. A new method using power spectrum of different orders to measure depth of phase gratings.three gratings were tested in this paper and the calculated depth was givem. The testing results of diffractive order of 6 gratings-about many orders itensity-were listed in table, The error of results is under 5%..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 495 (2004)
Numeric Simulation of Laser Propagation in Atmospheric Turbulence
ZHOU Wen-ming, XU Jun, ZHANG Qing-hua, WENG Xiao-dong, and LI Jun
Statistical characteristics and basic model of atmospheric turbulence are reported Using random number sequence generated by randomizer of SVS-Fortran as random variable, random process of atmospheric turbulence is objectively described A equivalent model of horizontal atmospheric turbulence is constructed through FFT Statistical characteristics and basic model of atmospheric turbulence are reported Using random number sequence generated by randomizer of SVS-Fortran as random variable, random process of atmospheric turbulence is objectively described A equivalent model of horizontal atmospheric turbulence is constructed through FFT and filtering. Basing on Karman spectra model of atmospheric index-of-refraction power spectra density and the Generalized Huygens-FYesnel diffraction integral theory, the process of laser propagation in atmospheric turbulence is simulated with an efficient two-dimensional FFT and IFFT by computer. It is shown that additory phase generated by random phase screens reflected characteristic parameter of structure of atmospheric turbulence..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 499 (2004)
Optical Waveguide Calculatid and Discussion with Finite-Difference Beam Propagation Method
LIN Bin, LIAN Hua, and JIN Meng-bi
This paper mainly covers the issue of Finite-Difference Beam Propagation Method (FD-BPM), which is one of the numerical methods of optical waveguide calculation. In order to discuss the problem and bring in the foundation of the method, the following problem is discussed ordinarily: theory of optical waveguide, numericThis paper mainly covers the issue of Finite-Difference Beam Propagation Method (FD-BPM), which is one of the numerical methods of optical waveguide calculation. In order to discuss the problem and bring in the foundation of the method, the following problem is discussed ordinarily: theory of optical waveguide, numerical method of optical waveguide, difference method of partial differential equation. With the basis, the FD-BPM becomes clear. After all these theories, the boundary condition, especially the transparent boundary condition (TBC) are discussed. At last, a concrete optical waveguide structure is inducted. A series of calculations and discussions are followed in order to compare the usage of different parameters..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 503 (2004)
Numerical Simulation of Refraction Effect within Shock Wave Layer on The Supersonic Aerocraft
LI Dun, JI Chu-qun, and MA Han-dong
The shock wave around blunt is simulated numerically by solving three-dimensional Euler equations with Godunov stiucture mesh method Taking into account density and pressure distribution, the flow field is divided into uniformity. inhomogeneity and shock wave layer. When optical beam passes the shock wave of high pressThe shock wave around blunt is simulated numerically by solving three-dimensional Euler equations with Godunov stiucture mesh method Taking into account density and pressure distribution, the flow field is divided into uniformity. inhomogeneity and shock wave layer. When optical beam passes the shock wave of high pressure and density come into being supersonic vehicle front, the refraction is calculated numerically. The results show that the refraction is influenced largely by shock wave. It is efficient to amend refraction by simulating flow field..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 507 (2004)
Growth study of φ80 mm Nd:YAG Crystals by Czochralski Method
CHEMG Hui-yun, MA Xiao-ming, LIU Rui-ting, XU Xue-zhen, and GUI You-xi
80 mm in diameter and 200 mm in length available for fabrication, with high optical quality Nd:YAG crystals were successfully grown by Czochralski method. Growth equipments, growth parameters and temperature field conditions are discussed and optimized To solve the problem of crystal crack for radial large diameter dur80 mm in diameter and 200 mm in length available for fabrication, with high optical quality Nd:YAG crystals were successfully grown by Czochralski method. Growth equipments, growth parameters and temperature field conditions are discussed and optimized To solve the problem of crystal crack for radial large diameter during growth process, the mechanisms of crystal crack are analyzed, some suitable mend measure are carried out and proved to be effective..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 510 (2004)
Raman Spectra of Nano-SiC Thin Film Prepared by Pulse Laser Crystallization
YU Wei, HE Jie, SUN Yun-tao, ZHU Hai-feng, HAN Li, and FU Guang-sheng
The pulsed laser crystallization of silicon carbon (SiC) thin films has been implemented by XeCl excimer laser. Raman scattering spectroscopy of the as-deposited and post annealing films has been analyzed The effect of laser energy on nano-SiC films structure and phase characterization has been studied The result showsThe pulsed laser crystallization of silicon carbon (SiC) thin films has been implemented by XeCl excimer laser. Raman scattering spectroscopy of the as-deposited and post annealing films has been analyzed The effect of laser energy on nano-SiC films structure and phase characterization has been studied The result shows that Raman peaks of crystalline nano-SiC nlms become broad and exist red-shift comparing with that of bulk SiC. The separation into crystalline silicon and carbon accompanying SiC crystallization is identified by the Raman measurement It has been shown that the crystallinty of annealed films increase with laser energy, while the degree of phase separation decreases..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 513 (2004)
On Growth Rate of the Ag Thin Film Versus Ambient Pressure in Pulse Laser Ablation
WANG Ying-long, ZHOU Yang, FU Guang-sheng, PENG Ying-cai, CHU Li-zhi, and ZHANG Rong-mei
In order to explain quantitatively the relation between the growth rate of Ag thin film and ambient gas pressure in the pulsed laser ablation, considering the dynamic process of the ablated particles in inert ambient and the deposition and resputtermg of thin films, supposing the probability of resputtering is proportiIn order to explain quantitatively the relation between the growth rate of Ag thin film and ambient gas pressure in the pulsed laser ablation, considering the dynamic process of the ablated particles in inert ambient and the deposition and resputtermg of thin films, supposing the probability of resputtering is proportional to kinetic energy of the ablated particles, the dynamic model of growing film is establish. The experiment result of T.Scharf et al. is explained quantitatively by considering the big grains..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 516 (2004)
Characters Study of the ZrO2 Films in Different Oxygen Partial Pressure
ZHANG Dong-ping, SHAO Jian-da, SHAO Shu-ying, Qi Hong-ji, GAO Wei-dong, and FAN Zheng-xiu
ZrO2 films were deposited by electron beam evaporation in different oxygen pressure. The effect of oxygen pressure during film deposition on the films' microstructure, optical characters and laser induced damage threshold (UDT) were studied by scanning probe microscopy, optical spectrometer and UDT measurement.ZrO2 films were deposited by electron beam evaporation in different oxygen pressure. The effect of oxygen pressure during film deposition on the films' microstructure, optical characters and laser induced damage threshold (UDT) were studied by scanning probe microscopy, optical spectrometer and UDT measurement..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 519 (2004)
Study on the Effect of the Electric Pumping Parameter on the Optical Efficiency of Flashlamp in Amplifier
CHEN Yuan-bin, YU Hai-wu, HE Shao-bo, GUO Liang-fu, YANG Dong, LIU Yong, HUANG Zheng, LI Yi-zheng, and CHEN De-huai
The effect of the electric pumping parameters on the large dimension flashlamp was studied which includes the effect of preionization and pulsh length. The result indicates that the preionization technology will increase optical efficiency about 7.8%, and the efficiency will increase about 2.0% with the pump duration sThe effect of the electric pumping parameters on the large dimension flashlamp was studied which includes the effect of preionization and pulsh length. The result indicates that the preionization technology will increase optical efficiency about 7.8%, and the efficiency will increase about 2.0% with the pump duration shorten 50 μs..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 522 (2004)
Research and Implementation of the CMOS Grating Measurement System
LIAN Hua, YU Yong, and CHAO Xiang-qun
A CMOS grating measurement system has been designed which connects the traditional optical system with CMOS to catch image, USB to translate the image data and computer to process the image data Several ways to catch the image and by the use of the visual C++ computer language to process the image have been got.A CMOS grating measurement system has been designed which connects the traditional optical system with CMOS to catch image, USB to translate the image data and computer to process the image data Several ways to catch the image and by the use of the visual C++ computer language to process the image have been got..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 526 (2004)
Convergence Coupled-Wave Analysis of Color Separating Grating
YANG Chun-lin, XU Qiao, ZHOU Li-shu, and YANG Li-min
According to the Maxwell equations, the diffraction characteristics of the color-separating grating (CSG) usea in ICF system have been calculated. The coupler-wave analysis and enhanced transmittance matrix have been employed during the calculation process. The results that get by the method, which used in this рapеr, According to the Maxwell equations, the diffraction characteristics of the color-separating grating (CSG) usea in ICF system have been calculated. The coupler-wave analysis and enhanced transmittance matrix have been employed during the calculation process. The results that get by the method, which used in this рapеr, are better than the results that get by the traditional scale method The calculation shows that the shorter of the period of the CSG, the lower of the diffraction efficiency of 3ω at zero order..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue s1, 529 (2004)
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20