Journals >Acta Photonica Sinica
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2009
Volume: 38 Issue 2
49 Article(s)
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Research Article
Coupling Conditions of Disk Whispering Gallery Mode
ZHOU Jian-ying, DAI Mi-te, HAO Ying-lei, YANG Jian-yi, WANG Ming-hua, and JIANG Xiao-qing
With the geometrical optics theory of waveguide and considering quality factor or photon lifetime,general whispering gallery modes resonating condition of large size disk were obtained.The coupling coefficient between the large size disk and waveguide was investigated by the photon tunneling effect.The coupling conditiWith the geometrical optics theory of waveguide and considering quality factor or photon lifetime,general whispering gallery modes resonating condition of large size disk were obtained.The coupling coefficient between the large size disk and waveguide was investigated by the photon tunneling effect.The coupling condition of lithium niobate disk electro-optic modulator under limitation of microwave electrode width was detailed,which quality factor was about 5×105.A push-pull lithium niobate disk modulator which was coupled to a Mach-Zehnder lithium niobate waveguide was proposed to lower further driving-voltage and reduce the device size..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 264 (2009)
Optical System Design of Two-Dimensional Array of 365 nm UV LED
LU Yong-jun, XU Wen-hai, QU Yan-ling, ZHAO Huan, and SONG Min
An application research on the high power 365nm UV LEDs widely used in the field of UV curing was performed,and a technical method using a two-dimensional array arrangement was suggested to realize the accumulation of their energy.The principle of optimum designing and an emulation software were provided.The emulating An application research on the high power 365nm UV LEDs widely used in the field of UV curing was performed,and a technical method using a two-dimensional array arrangement was suggested to realize the accumulation of their energy.The principle of optimum designing and an emulation software were provided.The emulating results exhibit the feasibility of the optical two-dimensional-array design scheme,which can reach many requirements in practical applications,including the irradiance intensity,the size and profile of spots,and the back-working distance.According to technical requirements occurred in a practical application case,the proposed system can provide a line-type irradiance spot of 50×10 mm2,a back working distance of more than 50mm,and an irradiance intensity of more than 1000 mW/cm2.And the proposed optical two-dimensional-array design scheme is convinced of an optimum designing in the configuration side of optical system..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 268 (2009)
Low Threshold Stretched-pulses Mode-locked Er3+-doped Fiber Laser with Ring Cavity
BAI Jing, WANG Yi-shan, CHEN Guo-fu, ZHAO Wei, YANG Zhi, ZHANG Wei, LIU Hong-jun, and CLAUDIO P
A low threshold stretched-pulses mode-locked Erbium-doped fiber ring cavity femtosecond laser with small positive-dispersion Er3+-doped fiber was demonstrated.By introducing the small positive-dispersion fiber,the pulse energy and spectrum width were improved,the sideband of the spectrum was effectively restrained,and A low threshold stretched-pulses mode-locked Erbium-doped fiber ring cavity femtosecond laser with small positive-dispersion Er3+-doped fiber was demonstrated.By introducing the small positive-dispersion fiber,the pulse energy and spectrum width were improved,the sideband of the spectrum was effectively restrained,and the self-starting pump power threshold was only 90 mW.The passive mode-locked continued to a pump power level as low as 29 mW.Self-starting mode-locked pulses with time duration of 175 fs,spectral width of 40 nm and repetition rate of 33 MHz were achieved by using this stretched-pulse configuration..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 237 (2009)
Fabrication of Micro-grating Structures by Nanosecond Laser Ablation of Chrome Film on Glass Substrate
ZHANG Heng, ZHOU Yun, ZHOU Lei, and CHEN Lin-sen
A method of etching micro-grating structures (MGSs) by ablating chrome film on glass was investigated,which was used the interference laser of 351 nm diode-pumped solid-state laser (DPSSL) pulses.Through changing the experimental parameters such as laser power,number of laser pulses，the influences of these parameters oA method of etching micro-grating structures (MGSs) by ablating chrome film on glass was investigated,which was used the interference laser of 351 nm diode-pumped solid-state laser (DPSSL) pulses.Through changing the experimental parameters such as laser power,number of laser pulses，the influences of these parameters on the depth of grooves and diffraction efficiency of MGSs were analyzed.Measured by conventional optical microscopy and atomic force microscopy (AFM),the highest depth of MGSs is 1.01 μm.The first-order diffraction efficiency of the MGSs was measured using 532 nm laser,and the highest of witch was 6.5%.The experimental results show that increasing the number of laser pulses properly in prpper laser energy,the depth of grooves and diffraction efficiency are increased..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 241 (2009)
Partially Coherent Cosh-Gaussian Beams
LI Chang-wei, and Lv Bai-da
The partially coherent cos-Gaussian (CsG) beam was introduced.Analytical expressions for the propagation of partially coherent CsG beams through a paraxial ABCD optical system and the M2 factor were derived.Propagation properties of partially coherent CsG beams through an astigmatic lens were studied.It is shown that tThe partially coherent cos-Gaussian (CsG) beam was introduced.Analytical expressions for the propagation of partially coherent CsG beams through a paraxial ABCD optical system and the M2 factor were derived.Propagation properties of partially coherent CsG beams through an astigmatic lens were studied.It is shown that the M2 factor of partially coherent CsG beams is dependent on the spatial coherence parameter and the decentered parameter of partially coherent CsG beams,but independent of the astigmatic coefficient of the lens.The Gaussian-like,flat-topped,and dark-hollow different intensity profiles at the geometrical focal plane couldn be achieved by a suitable choice of the spatial coherence parameter,decentered parameter or astigmatic coefficient.Thus,the spatial shaping of partially coherent CsG beams is realizable..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 245 (2009)
Optical Performance of China-made Nd3+-doped Ceramic Disk
CAI Hong, ZHOU Jun, FENG Tao, ZHANG Jian, QI Yun-feng, LOU Qi-hong, JIANG Dan-yu, AN Li-qiong, WANG Shi-wei, DONG Jing-xing, and WEI Yun-rong
The optical performances of China-made Nd∶YAG and Nd∶YSAG ceramic disks were studied.The fabrication and spectra properties of Nd∶YAG and Nd∶YSAG transparent ceramic were introduced.For Nd∶YAG ceramic disk laser,the laser output with a central wavelength of 1 064.2 nm and a Full Width Half Maximum (FWHM) of 0.89 nm wasThe optical performances of China-made Nd∶YAG and Nd∶YSAG ceramic disks were studied.The fabrication and spectra properties of Nd∶YAG and Nd∶YSAG transparent ceramic were introduced.For Nd∶YAG ceramic disk laser,the laser output with a central wavelength of 1 064.2 nm and a Full Width Half Maximum (FWHM) of 0.89 nm was achieved.The maximum output power was 0.319W with laser threshold of 0.267 W.For the novel Nd∶YSAG ceramic laser,which has the prolonged fluorescence lifetime and can achieve high-level doping,the laser central wavelength was 1 063.8 nm ,and the FWHM was 1.6 nm.The maximum output power was 0.356W with slope efficiency of 23.2%.The results demonstrate that China-made Nd∶YSAG ceramic is suitable for short-pulse microchip laser..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 250 (2009)
Fixing Laser Radar Based on Half-sine Correlation Method
ZHANG Xiu-da, YAN Hui-min, YANG Hua-jun, and LI Yan
Fixing imaging 3D laser radar based on half-sine to rectangle correlation method was presented.Fourier series were employed to analyze half-sine to rectangle correction process.Theoretical analysis shows that half-sine to rectangle correlation can suppress high frequency noise and increase alternative component of moduFixing imaging 3D laser radar based on half-sine to rectangle correlation method was presented.Fourier series were employed to analyze half-sine to rectangle correction process.Theoretical analysis shows that half-sine to rectangle correlation can suppress high frequency noise and increase alternative component of modulation at the same time.The new method can achieve larger laser output power,longer measuring range while without suffering accuracy decrease.100 square meters targets in a distant about 20~70 m were detected by equipment based on the new method.The experiment shows that laser radar based on new method get an accuracy about 0.3 meters in a distance about 60 meters.The experiment result verifies the theory result..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 255 (2009)
Evolution of Phase Singularities of Higher-order Bessel Beam Diffracted by Aperture
[in Chinese], and [in Chinese]
The analytical expression for the propagation of higher-order Bessel beams through an aperture paraxial optical ABCD system was derived,which was used to study the evolution of phase singularities of a higher-order Bessel beam diffracted by an aperture.It shows that there always exists an optical vortex at the center oThe analytical expression for the propagation of higher-order Bessel beams through an aperture paraxial optical ABCD system was derived,which was used to study the evolution of phase singularities of a higher-order Bessel beam diffracted by an aperture.It shows that there always exists an optical vortex at the center of the diffracted higher-order Bessel beams and the topological change is conserved during the propagation,but the size of the vortex core varies with the aperture radius,propagation distance and beam number.Depending on the aperture radius and propagation distance,the circular edge dislocations may vanish or appear..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 259 (2009)
Multiple Channeled Flat-top Transmission of One-dimensional Photonic Crystal Super-lattice
HAN Peng, HUANG Jie-bin, CHEN Chao-xiong, and YANG Guan-ling
Based on the principle of one-dimensional photonic crystal super-lattice and coupled optical microcavities,a new scheme to achieve multiple channeled optical filters with flat-top transmission peaks was presented.The traditional cavities of single material were replaced by photonic crystals with finite period,and thus Based on the principle of one-dimensional photonic crystal super-lattice and coupled optical microcavities,a new scheme to achieve multiple channeled optical filters with flat-top transmission peaks was presented.The traditional cavities of single material were replaced by photonic crystals with finite period,and thus a super-lattice structure was constructed.Using transfer-matrix method,the structural spectra and the influence of the structural and material parameters on the locations and the FWHMs of the transmission peaks were studied.The numerical results show that this structure has a rather wide photonic band gap,in which there are multiple flat-top transmission peaks.These peaks are symmetrical,with high transmission rate and high error tolerance.The locations of these peaks can be calculated exactly,and the strict analytic expression was presented..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 272 (2009)
Effect of Inserted Metal Ag Layer on Photonic Band Gap of One-dimensional C60/AlN Photonic Crystals
YAN Ling-yun, HAN Pei-de, CHEN Jing, ZHANG Cai-li, LIU Xu-guang, and XU Bing-she
The photonic band structure of one-dimensional metallic cladding photonic crystals was simulated by the transfer matrix method (TMM).By inserting metal Ag layers between C60 and AlN layers,a new metallic cladding photonic crystal (C60/Ag/AlN)n could be made.The new structure shows a wider band gap than in the structureThe photonic band structure of one-dimensional metallic cladding photonic crystals was simulated by the transfer matrix method (TMM).By inserting metal Ag layers between C60 and AlN layers,a new metallic cladding photonic crystal (C60/Ag/AlN)n could be made.The new structure shows a wider band gap than in the structure of (C60/AlN)n in UV region.The modes can broaden the band gaps by 73.91% and exhibit a high reflectivity of 91.01%.The metallic cladding photonic crystals is ideal candidates for making reflector.The characteristics of the structure could be used in a low-loss broad band reflector..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 277 (2009)
Fabrication of Germanium Inverse Opal Three-dimensional Photonic Crystal by LPCVD
LI Yu-jie, XIE Kai, XU Jing, HAN Yu, TU Sheng-yi, and LI Yun-peng
Monodisperse silica microspheres were assembled into three-dimensional colloidal crystal template with long-ranged order by solvent vaporization convection self-assembly method.Low Pressure Chemical Vapour Deposition(LPCVD) method was used to fill the voids of silica colloidal crystals template with high refractive indMonodisperse silica microspheres were assembled into three-dimensional colloidal crystal template with long-ranged order by solvent vaporization convection self-assembly method.Low Pressure Chemical Vapour Deposition(LPCVD) method was used to fill the voids of silica colloidal crystals template with high refractive index material germanium,then silica colloidal crystals template was removed by an acid etching.Thus germanium three-dimensional inverse opal photonic crystal was obtained.The modality,component and structure of the resulted samples were characterized by scanning electron microscopy,X-ray diffraction and UV-VIS-NIR spectroscopy.Results show that germanium of high crystalline quality is homogeneously distributed inside the voids of silica template.The filling fraction of germanium can be controlled by changing the conditions of LPCVD.The samples have optic reflective apex and show the photonic band gap effects.The experiment optic capability is inosculated with the calculated one..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 281 (2009)
Tuning Characteristics and Quality Factor of One-dimension Photonic Crystal Micro-cavity
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The tuning characteristics and quality factor of one-dimension photonic crystal micro-cavity with symmetrical structure and unsymmetrical structure with transfer matrix method were researched.Results show that with the increase of optical thickness of defect layer，the center wavelength of defect mode will increase and The tuning characteristics and quality factor of one-dimension photonic crystal micro-cavity with symmetrical structure and unsymmetrical structure with transfer matrix method were researched.Results show that with the increase of optical thickness of defect layer，the center wavelength of defect mode will increase and tuning characteristics of micro-cavity relate to the refractive index of medium which surround the defect layer.Compared with symmetrical structure，unsymmetrical structure can achieve linear tuning with wide wavelength range but smaller variation of the optical thickness of defect layer.Quality factor will increase first and then reduce with increase the thickness of the defect layer and it has maximum when the center wavelength of defect mode is λ0.The array of medium with high or low refractive index affects the quality factor of micro-cavity..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 285 (2009)
Impurity Band in One-dimensional Photonic Crystal Containing Defect Layers with Negative Refractive Index
AN Li-ping, and LIU Nian-hua
The transmission through one-dimensional photonic crystal with negative refractive index defects was studied by using transfer matrix method.Quarter-wave stack photonic crystal of 19 periods with three negative refractive index defects were taken as an example for numerical calculation.It is found that when the refractThe transmission through one-dimensional photonic crystal with negative refractive index defects was studied by using transfer matrix method.Quarter-wave stack photonic crystal of 19 periods with three negative refractive index defects were taken as an example for numerical calculation.It is found that when the refractive index of defect was changed,the coupling effect between the defect modes was varied,which results in the change of the impurity band.Some sharp transmission peaks apper in the forbidden band when the refractive index of defects is appropriate.It is different from the the impurity band formed by positive refractive index defects..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 289 (2009)
Numerical Research on One Dimension Nonlinear Photonic Crystal All-optical Switching
WU Bing-bing, HE Xiao-dong, XUE Wei, QUAN Wei, HU Gui-jun, and WANG Yuan-yuan
Nonlinear Kerr-type medium was doped in defect layers of photonic crystals.Based on the dynamical shift of defect mode caused by Kerr nonlinear effect,two schemes of optical switching and the calculating programs with method of FD-TD were designed to simulate optical switching.Photonic localization and frequency mixingNonlinear Kerr-type medium was doped in defect layers of photonic crystals.Based on the dynamical shift of defect mode caused by Kerr nonlinear effect,two schemes of optical switching and the calculating programs with method of FD-TD were designed to simulate optical switching.Photonic localization and frequency mixing effects were discussed..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 293 (2009)
Effect of Electric Filed Enhancement on Laser-induced Damage Morphology of Multi-layer Dielectric Grating*
KONG Wei-jin, LIU Shi-jie, FAN Zheng-xiu, and SHAO Jian-da
The effect of electric field enhancement on laser-induced damage morphology of multi-layer dielectric gratings was investigated. Electric field distribution was calculated by using the Fourier mode method. Numerical treatment shows that the peak electric field occurs at the groove edge opposite to the incident directioThe effect of electric field enhancement on laser-induced damage morphology of multi-layer dielectric gratings was investigated. Electric field distribution was calculated by using the Fourier mode method. Numerical treatment shows that the peak electric field occurs at the groove edge opposite to the incident direction by nearly a magnitude of two. Laser-induced damage threshold of 6.61 J/cm2 was obtained for 12 ns pulses at 1 064 nm with TE mode and 51.2° incident. Scanning electron microscopy (SEM) of damage morphology shows that the initial damage occurs from the place where the electric filed is strongly enhanced..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 298 (2009)
Effects of Sputtering Parameters on Optical Constant of NiOx Thin Films*
LI Xiao-gang, and TANG Xiao-dong
The effects of sputtering parameters on optical constant of NiOx thin films prepared by reactive magnetron sputtering were studied by spectroscopic ellipsometry, XRD and XPS methods. The optical constant of the deposited films became smaller with O2/Ar flow ratios increasing. After annealing, the refractive index showsThe effects of sputtering parameters on optical constant of NiOx thin films prepared by reactive magnetron sputtering were studied by spectroscopic ellipsometry, XRD and XPS methods. The optical constant of the deposited films became smaller with O2/Ar flow ratios increasing. After annealing, the refractive index shows an increase, especially at a high O2/Ar flow ratio, while the extinction coefficient reduced by about 50%. The refractive index is greater for a higher sputtering power while smaller for a higher work pressure. It is related to the existence of interstitial oxygen and vacancy of Ni, the decomposition of NiOx and compactness degree of NiOx films, respectively..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 302 (2009)
Development of Antireflection Thin Films Based on Glan-Taylor Prism in Visible Spectrum and 1 064 nm
HAO Dian-zhong, SU Fu-fang, SONG Lian-ke, WU Fu-quan, and LI Guo-hua
In order to improve increase the transmissivity of the Glan-Taylor prism,antireflection films for the visible spectrum and 1 064 nm were designed and evaporated on the Glan-Taylor prism.Al2O3 and ZrO2 were selected as the transition layer and the buffer layer to improve the adhesion between the coating and the Iceland In order to improve increase the transmissivity of the Glan-Taylor prism,antireflection films for the visible spectrum and 1 064 nm were designed and evaporated on the Glan-Taylor prism.Al2O3 and ZrO2 were selected as the transition layer and the buffer layer to improve the adhesion between the coating and the Iceland crystal.The simplex refinement method was used to optimize coatings.A multilayer antireflection coating was deposited using electron beam evaporation and ion assisted deposition.While coating thickness and deposition rate were monitored and demonstrated by quartz crystal oscillation.The testing results indicate that:the value of the average residual reflection is below 0.5% in visible spectrum and 1 064 nm,and the adhesive power between the coating and the Iceland crystal is good..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 307 (2009)
Weak Magnetic Field Response Characteristics of Magnetostrictive Materials
TONG Rong-guang, ZHAO Jian-lin, CHENG Zhen-long, and ZHOU Wang-min
Based on the application requirements of magnetostrictive materials in weak magnetic field sensor,the magnetic field response sensitivities of Tb-Dy-Fe material and Fe-Ga alloy were measured by using Michelson interferometory.The magnetic field and temperature responses of Fe-Ga alloy under different external stresses Based on the application requirements of magnetostrictive materials in weak magnetic field sensor,the magnetic field response sensitivities of Tb-Dy-Fe material and Fe-Ga alloy were measured by using Michelson interferometory.The magnetic field and temperature responses of Fe-Ga alloy under different external stresses were also experimentally analyzed in detail.The experimental results show that when the magnetic induction is about 16 mT in the condition of no external stress,the magnetic field response sensitivity of Fe-Ga alloy is much higher than that of Tb-Dy-Fe material.For the magnetic sensors requiring high sensitivity and small measurement range,Fe-Ga alloy are more suitable as the sensitive material of the sensors.Especially,under 1.2 MPa external stress and 26 mT offset magnetic field,Fe-Ga alloy will exhibit preferable magnetic field response sensitivity and larger saturation magnetostriction coefficient,which can be considered in the optimal working state.Therefore,the measured magnetic field and temperature responses curves of those materials could be used as the parameter design references of weak magnetic field sensors..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 311 (2009)
Optical Properties of Co-doped Stoichiometric Lithium Niobate
JIA Bao-shen, HE Yan-lan, ZHAO Ye-quan, and SHEN Yan
Optical quality near stoichiometric lithium niobate doped with Fe2O3 and MnO was grown by top-seed solution method.The results of UV absorption indicate that the ratio of n(Li)/n(Nb) is close to stoichiometric.The exponential gain coefficient,diffraction efficiency and response time were measured by tow wave coupling lOptical quality near stoichiometric lithium niobate doped with Fe2O3 and MnO was grown by top-seed solution method.The results of UV absorption indicate that the ratio of n(Li)/n(Nb) is close to stoichiometric.The exponential gain coefficient,diffraction efficiency and response time were measured by tow wave coupling light.The results show that the exponential gain coefficient and diffraction efficiency of near stoichiometric crystal reach to 25 cm－1 and 68.3%,respectively,while response time is less than 1 second.Holographic storage experiment was carried out using the grown crystal.The results indicate that the quality of image storage is much batter than that of congruent crystal with the same dopants,and the recording speed is three times faster than that of congruent crystal..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 352 (2009)
Phase Retrieval on Site Testing for Large Mirrors
LI Sheng-yi, HU Xiao-jun, and WU Yu-lie
To meet the requirement of on site testing in the manufacture of large mirror surfaces,a new method using phase retrieval technology was developed.A phase retrieval testing system based on the wave field at defocus was established together with the phase retrieval algorithm that serves the system.The testing system is To meet the requirement of on site testing in the manufacture of large mirror surfaces,a new method using phase retrieval technology was developed.A phase retrieval testing system based on the wave field at defocus was established together with the phase retrieval algorithm that serves the system.The testing system is simple and free from vibration,based on which,the error sources with testing precision and scope were analyzed in detail.The reliability for practical testing was also studied according to the requirement of on sit testing.The testing for a ball mirror of 430 mm aperture was carried out,where the affection from different testing configuration was also studied.The testing result showed high consistency compared with the result from interferometer.It shows that this method is feasible for high accuracy and suit for the requirement of polishing process..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 365 (2009)
A New Optical Characterists Measurement for Optical Transition Radiation
ZHENG Yan-fang, and CHEN Liang-yi
In order to solve the problem that the paths of angular distribution at focus plane and beam spot at image plane can not be measured at the same time,an advanced measurement of optical transition radiation was proposed.The light path principle and the machine structure were introduced.The technical difficulties and resIn order to solve the problem that the paths of angular distribution at focus plane and beam spot at image plane can not be measured at the same time,an advanced measurement of optical transition radiation was proposed.The light path principle and the machine structure were introduced.The technical difficulties and resolvent of OTR lens ,the beamsplitting prism and lead shield were analyzed.The results show that the system overcomes single function measure and the bad imaging.The better pictures of angular distribution and beam spot can be obtained synchronously on ICCD cameras.The high power radiations such as X-rays disturb the pattern collection intensively,and are mostly shielded..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 371 (2009)
Influence of Earth Radiation on Photoelectric Detection System Based on Space
XIAO Xiang-guo, WANG Zhong-huo, BAI Jia-guang, and Liu Xue-bin
A illuminating model of earth radiation was built,and the luminous intensity of the space target surface from the earth radiation was calculated.The results show that the earth radiation is enough illumination for photoelectric detection system based on space.The stray-light from atmosphere-earth was researched,and a mA illuminating model of earth radiation was built,and the luminous intensity of the space target surface from the earth radiation was calculated.The results show that the earth radiation is enough illumination for photoelectric detection system based on space.The stray-light from atmosphere-earth was researched,and a method how to evaluate the stray-light influence of earth radiation on photoelectric detection system based on space was investigated..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 375 (2009)
Normal Incidence Two-mirror Reflecting Systems Designed at EUV and X-ray
SHEN Zheng-xiang, MU Bao-zhong, WANG Zhan-shan, WANG Li, MA Bin, JI Yi-qin, and LIU Hua-song
Based on the third-order aberration theory of two-mirror reflecting system, the influence of the geometrical aberrations on the performance of normal incidence telescopes was analyzed. The change trends of the angular size of the blur spot θ with the f-number and half-field angle uP were concluded. The angular blur spoBased on the third-order aberration theory of two-mirror reflecting system, the influence of the geometrical aberrations on the performance of normal incidence telescopes was analyzed. The change trends of the angular size of the blur spot θ with the f-number and half-field angle uP were concluded. The angular blur spot θ increased with the increase of the half-field angle uP and the decrease of f-number, and the θ increased more sharply when the f-number was less than 10 or the half-field angle uP was more than 0.005. And, four kinds of typical reflecting systems were discussed in detail. Comparing the results, it is found that the angular blur spots in a Dall-Kirkham system and an inverse Dall-Kirkham system are at the same order of magnitude, which is almost ten times of a Cassegrain system′s. The θ of an R-C system is the smallest, which is one tenth of a Cassegrain system′s. It is useful to estimate the size of the aberration blur by the formulae without going to the trouble of making a raytrace analysis..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 392 (2009)
Measurement of Polarization of X-ray with Polarization Spectrometer
SHI Jun, XIAO Sha-li, WANG Hong-jian, TANG Chang-huan, and QIAN jia-yu
For the research on anisotropy of plasma and ascertainment the presence of electron beams in high-temperature plasmas,a X-ray polarization spectrometer wasdesigned.The theory of the polarization spectroscopy was investigated and the ways of polarization calculation were presented.The polarization spectrometer could meaFor the research on anisotropy of plasma and ascertainment the presence of electron beams in high-temperature plasmas,a X-ray polarization spectrometer wasdesigned.The theory of the polarization spectroscopy was investigated and the ways of polarization calculation were presented.The polarization spectrometer could measure X-ray lines radiated by plasma in the directions of vertical and horizontal.In the vertical configuration the plane of dispersion of the crystal is spherical Mica and in the horizontal configuration the plane of dispersion of the crystal is flat PET.The X-ray spectra emitted from the planar aluminum target was photographed by using the polarization spectrometer with two image plates at the 2×10 J facilities in Research Center of Laser Fusion.The experimental result shows that the resonance line w,the magnetic quadrupole M2 line,the intercombination line y and the forbidden line z of He-like Al are obtained with PET crystal in the direction of horizontal.So the PET crystal is suitable for diagnosing soft X-ray spectroscopy.The resonance line w of He-like Al was obtained with Mica crystal and its satellite lines were vanished.At the same time the reasons were analyzed and the X-ray line polarization spectrometer was planned to redesign in order to detect the EBIT device..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 396 (2009)
Novel Post-processing Algorithm to Reduce Still Image Compression Artifacts
SUN Wen-fang, ZHAO Yi-gong, and ZHU Hong
A post-processing algorithm of still image compression was proposed. Iterative contourlet-based image interpolation was implemented to revive the highpass information, which was then fused with the highpass information of the decompressed image to further preserve the significant wavelet coefficients. The algorithm helA post-processing algorithm of still image compression was proposed. Iterative contourlet-based image interpolation was implemented to revive the highpass information, which was then fused with the highpass information of the decompressed image to further preserve the significant wavelet coefficients. The algorithm helped to reduce compression artifacts and improve regularity along edges of the decompressed image at low bitrates especially. The ability of the proposed method was demonstrated under JPEG2 000 and SPIHT compression systems. Only for once iteration, the PSNR (peak signal-to-noise ratio) of the post-processed image may improve 0.05~0.2 dB than that of the decompressed image. Ringing artifacts decrease with the increase of the number iteration..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 430 (2009)
Characteristics of Independence on Image Gray Level in Pattern Matching Algorithm and its Application
SUN Ming-lei, ZONG Guang-hua, BI Shu-sheng, and YU Jing-jun
A characteristic that Normalized Cross Correlation Operating (NCCO) results independent of image gray levels in pattern matching for image feature positioning was presented.In the field of microscopic vision research,the majority of images can be approximated to an image with three gray levels,or even binary image.So wA characteristic that Normalized Cross Correlation Operating (NCCO) results independent of image gray levels in pattern matching for image feature positioning was presented.In the field of microscopic vision research,the majority of images can be approximated to an image with three gray levels,or even binary image.So with this attractive feature,a method of improved pattern matching algorithms was presented.Experimental results show that the characteristic of gray level independence can give guidance to designing template images,reducing time consumption of calculations,and improving illuminating conditions..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 435 (2009)
Color Property Analysis of Remote Sensing Imagery
LIU Jia-hang, YANG Jian-feng, and FANG Tao
In order to acquire some identified shadow features which can be easily obtained,several common color models used in image color space were summarized,and then the intensity,the hue,the saturation,the relation between G magnitude and B magnitude of shadows in color remote sensed images were studied.Based on a series ofIn order to acquire some identified shadow features which can be easily obtained,several common color models used in image color space were summarized,and then the intensity,the hue,the saturation,the relation between G magnitude and B magnitude of shadows in color remote sensed images were studied.Based on a series of experiments and theoretical analysis,several conclusions were obtained:1) higher-level values in hue channel can indicate the locations of shadow in a certain degree; 2) low intensity is an important property of shadows in remote sensed image; 3) the saturation distributions of most shadowed areas are similar in general; 4) to the different shadow areas in a same image,the G components are always higher than the B components or always lower than the B components in most cases,and also this relation keeps consistency in the statistical sense.Experiments indicate that these shadow features are useful for automatic shadow detection in color images and can be used as the basic features for model building..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 441 (2009)
Synthetic Aperture Imaging Ladar Imaging Algorithm
GUO Liang, XING Meng-dao, LIANG Yi, and TANG Yu
FMCW signal and its characteristic in balanced heterodyne detecting were described. The difference in instantaneous slant range between SAIL and conventional SAR were analyzed.A Doppler shift term was induced by the continuous motion of the platform that was ignored by conventional SAR in “stop-and-go” model.A refined FMCW signal and its characteristic in balanced heterodyne detecting were described. The difference in instantaneous slant range between SAIL and conventional SAR were analyzed.A Doppler shift term was induced by the continuous motion of the platform that was ignored by conventional SAR in “stop-and-go” model.A refined frequency scaling algorithm was deduced,which was suitable for airborne SAIL in stripmap model and was taking the Doppler shift term into account.The simulation result shows that the given algorithm can compensate for the effect of the continuous motion of the platform efficiently..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 448 (2009)
Measurement Method to Object Distances by Monocular Vision
ZHANG Fa-quan, LU Li-ping, SHEN Man-de, CHEN Liang-yi, and CUI Guang-zhao
A method to measure object distance by monocular vision was proposed.Position of one object′s conjugate image plane varied when the distance between it and the optical system was changed.The image on CCD was out of focus as a result of fixed CCD in cameras.Blur extent of images was scaled by width of image edge.Images A method to measure object distance by monocular vision was proposed.Position of one object′s conjugate image plane varied when the distance between it and the optical system was changed.The image on CCD was out of focus as a result of fixed CCD in cameras.Blur extent of images was scaled by width of image edge.Images were processed by wavelet transform and widths of blurred image edge were detected.Real distance between object and optical system was calculated through cubic spline interpolation.The measurement method to object distance by monocular vision was realized.Results show that the method is feasible..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 453 (2009)
A Pyramid Transform of Image Denoising Algorithm Based on Morphology
XIANG Jing-bo, and SU Xiu-qin
An image de-noising algorithm based on adaptive-lifting laplacian pyramid transform and mathematical morphology was proposed.The source image was decomposed by the adaptive lifting Laplacian Pyramid.According to the statistics of the transform coefficients of natural image,the morphological dilation operator was applieAn image de-noising algorithm based on adaptive-lifting laplacian pyramid transform and mathematical morphology was proposed.The source image was decomposed by the adaptive lifting Laplacian Pyramid.According to the statistics of the transform coefficients of natural image,the morphological dilation operator was applied to extract the clustered significant coefficients in each subband resulting in the partitioning of each subband into significance clusters and insignificance space.The smoothing image of the input image was obtained using the wavelet threshold-denoising method whose threshhold was different in different subsets.Two subsets,and reconstruction image were combined.The experiment results demonstrate that the algorithm can denoise effectively,and keep the detail information.The method can improve the signal-to-noise ratio..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 457 (2009)
Atmospheric and Oceanic Optics
Method of Retrieving Refractive Index of Aerosol Particles
LI Xue-bin, GONG Chun-wen, HUANG Yin-bo, WEI He-li, and HU Huan-ling
A new method was proposed to retrieve imaginary part of aerosol refractive index by using two kinds of particle counters.One measured the optical size of aerosol particle,which was greatly effected by the refractive imaginary part,and the other one measured aerodynamic of aerosol particle size,which was not effected byA new method was proposed to retrieve imaginary part of aerosol refractive index by using two kinds of particle counters.One measured the optical size of aerosol particle,which was greatly effected by the refractive imaginary part,and the other one measured aerodynamic of aerosol particle size,which was not effected by refractive imaginary part.The aerosol refractive index was retrieved by combining the measurement of these two kinds of particle counters..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 401 (2009)
Belief Propagation Decoding of Low-density Parity-check Codes for Atmospheric Turbulent Optical PPM Communication Systems
CHEN Jia-jie, and LI Xiao-feng
BP decoding of LDPC code for weak atmospheric turbulent optical PPM systems was studied, and corresponding decoding algorithm was introduced according to the system model. Through theoretical analysis and extensive computer simulations, the result shows that the LDPC coded weak atmospheric turbulent optical PPM system BP decoding of LDPC code for weak atmospheric turbulent optical PPM systems was studied, and corresponding decoding algorithm was introduced according to the system model. Through theoretical analysis and extensive computer simulations, the result shows that the LDPC coded weak atmospheric turbulent optical PPM system has better BER than the uncoded weak atmospheric turbulent optical PPM system, but the BER performance of the system increases with the increase of slot..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 405 (2009)
Density of Phase Branch Points for a Light Wave Propagation in Atmospheric Turbulence
YUAN Ke-e, ZHU Wen-yue, and RAO Rui-zhong
Under Rytov approximation and geometrical optics approximation, a formula of the variance of the log-amplitude derivative was deduced for the case of a plane wave propagating through turbulence. It was clarified that the main factors, which determined the variance, were the Rytov variance, the turbulence inner scale anUnder Rytov approximation and geometrical optics approximation, a formula of the variance of the log-amplitude derivative was deduced for the case of a plane wave propagating through turbulence. It was clarified that the main factors, which determined the variance, were the Rytov variance, the turbulence inner scale and the Fresnel size. And, based on the formulae deduced by Voitsekhovich, the expression for density of phase branch points was modified. The relationship between the density and the above mentioned parameters was analyzed thoroughly, which indicates that the density increases with Rytov variance increasing and decreases with turbulence inner scale and Fresnel size increasing under the condition of Rytov variance less than 1..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 410 (2009)
Method of Laser Radar Cross Section Measuring with Atmosphere Condition Changing
BAO Xue-zhi, and GAO Wei
Using two-channel detection,influences on laser radar cross section measure accuracy caused by atmosphere condition changing were studied.The new formula of comparing measure was deduced.An experiment was carried out on the new formula,and its using qualification was discussed.Through measuring the diffuse reflection bUsing two-channel detection,influences on laser radar cross section measure accuracy caused by atmosphere condition changing were studied.The new formula of comparing measure was deduced.An experiment was carried out on the new formula,and its using qualification was discussed.Through measuring the diffuse reflection board′s LRCS in the outfield,the result indicates that the new formula can correct the measure error because of the atmosphere condition changing and help to improve measure accuracy,and its calculation is very brief and carried out easily..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 414 (2009)
Fiber Optics and Optical Communications
All-optical Modulation Format Conversion from NRZ to RZ Using SOA and Optical Bandpass Filter Converters*
XIE Yi-yuan, ZHANG Jian-guo, ZHAO Wei, YAN Shuang-yi, XIE Xiao-ping, and LIU Yuan-shan
An all-optical non return-to-zero (NRZ) to return-to-zero (RZ) modulation format converter using single semiconductor optical amplifier (SOA) and an optical band-pass filter (OBPF) was proposed. By adopting the ultra-fast SOA model associated with optical system software, the 10 Gbit/s NRZ-to-RZ format conversion was sAn all-optical non return-to-zero (NRZ) to return-to-zero (RZ) modulation format converter using single semiconductor optical amplifier (SOA) and an optical band-pass filter (OBPF) was proposed. By adopting the ultra-fast SOA model associated with optical system software, the 10 Gbit/s NRZ-to-RZ format conversion was successfully demonstrated with simulation. The proof-of-the-principle experiment at 10 Gbps was also demonstrated using the test SOA and OBF converter. The result shows that the BER is 1.0×10－9 when the power of RZ is －15 dBm,which are well coincidence with simulated results..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 315 (2009)
Output Spectrum Characteristics of MGTI-type Asymmetrical Optical Interleavers
WANG Chang, and ZHANG Juan
Based on Michelson-Gires-Tournois interferometer (MGTI) structure of interleaver that both of reflecting mirrors were replaced by two mirror Gires-Tournois etalons (GTEs).The appropriate value of structural parameters such as GTE front surface mirror reflectance,the cavity length of GTE and interferometer arm length diBased on Michelson-Gires-Tournois interferometer (MGTI) structure of interleaver that both of reflecting mirrors were replaced by two mirror Gires-Tournois etalons (GTEs).The appropriate value of structural parameters such as GTE front surface mirror reflectance,the cavity length of GTE and interferometer arm length difference were chosen.Four groups of spectrums that the ratio of wide bandwidth port to narrow bandwidth port at 3 dB passband (bandwidth ratio) was 1.69,1.83,2.13 and 2.14 respectively,were obtained.They have high channel isolation,wide flat-top passband and different periods.The effects of these structural parameters upon output spectrum characteristics were systematically investigated.The numerical simulation results indicate that asymmetrical interleavers of different bandwidth ratios could be obtained using this MGTI.GTE front surface mirror reflectance influences the passband bandwidth and channel isolation.And the two kinds of influences are different.Choosing appropriate GTE cavity length and interferometer arm length difference,different frequency periods can be obtained..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 321 (2009)
Choice Strategy of Dynamic Web Service Combination
MEN Peng, and DUAN Zhen-hua
In order to improve the utilization rate of optical network,an approach of selecting the top quality web services composition based on Petri nets was presented.A Petri net model,which represented the data dependent relationship between the service composition according to consumers' demands and the current availablIn order to improve the utilization rate of optical network,an approach of selecting the top quality web services composition based on Petri nets was presented.A Petri net model,which represented the data dependent relationship between the service composition according to consumers' demands and the current available services,was obtained.By calculating the T-variables relationships of the Petri net,plans of the service composition were obtained.And,the generalized stochastic Petri net (GSPN) was employed to analyze the performance of the plan.Compared with other approaches available,the results show that the presented method takes full advantages of Petri nets,such as easy description,analysis and evaluation of the systems,and can obtain the best plan of Web service compositions..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 325 (2009)
Evaluation of Outage Probability of Optical Communication System Impaired by Polarization Effects*
YUAN Fu-lai, LIU Han-kui, XIAO Shun-wen, and TIAN Xiao-xing
Using multiple importance sampling technique, the power penalty and outage probability of 10Gbit/s lightwave transmission system impaired by polarization-mode dispersion (PMD) and polarization-dependent loss (PDL) were investigated. The simulation results show that optical filter has significant influence on the power Using multiple importance sampling technique, the power penalty and outage probability of 10Gbit/s lightwave transmission system impaired by polarization-mode dispersion (PMD) and polarization-dependent loss (PDL) were investigated. The simulation results show that optical filter has significant influence on the power penalty, and the system with Fabry-Perot filter always performs better than that with four-order Gaussian filter. It is also found that the power penalty generally increases with the increasing of chirp factor, but the system performs best when chirp factor is about 0.5. It also demonstrated that DPSK is still more robust to PMD and PDL than OOK even though PMD and PDL coexist..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 329 (2009)
Modulation Schemes of Mobile Atmosphere Laser Communication Between Autos
LIN Zhi-qi, SONG Guo-ming, LIU Tao, and PANG Lin
Modulation scheme of atmosphere laser communication was discussed.Typical modulation schemes OOK,PPM,DPPM,DPIM and DH-PIM were introduced and its performances were analyzed.A new type of modulation called H-PPM was proposed,which was compared with the modulation scheme mentioned above.This type of modulation inherits tModulation scheme of atmosphere laser communication was discussed.Typical modulation schemes OOK,PPM,DPPM,DPIM and DH-PIM were introduced and its performances were analyzed.A new type of modulation called H-PPM was proposed,which was compared with the modulation scheme mentioned above.This type of modulation inherits the excellent bit error rate performance of standard PPM modulation scheme,it also need not the symbol synchronization when the information was demodulated at receiver.In this way,the design of receiver was simplified; and the difficulty of system was much reduced.Theoretical analysis and simulation results show that H-PPM is the best type of modulation for short instance,high reliability and little content laser communication between autos..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 334 (2009)
Fabrication of Er-Yb Co-doped Double-clad Fiber
HUANG Bang-cai, YI Yong-qing, DUAN Yun-feng, LIU Jun-hao, PANG Lu, ZHANG Peng, NING Ding, YUAN Shu-zhong, and DONG Xiao-yi
The MCVD and solution-doping technology for the Er-Yb co-doped double-clad fiber was reported.Using the MCVD manufacture technics,the fiber isolation layers(SiO2-P2O5-F) and the porous frits(SiO2-GeO2-P2O5) were deposited.The porous frits were soaked in the solutions of YbCl3 and ErCl3.Two fiber samples with 1:13 and 1The MCVD and solution-doping technology for the Er-Yb co-doped double-clad fiber was reported.Using the MCVD manufacture technics,the fiber isolation layers(SiO2-P2O5-F) and the porous frits(SiO2-GeO2-P2O5) were deposited.The porous frits were soaked in the solutions of YbCl3 and ErCl3.Two fiber samples with 1:13 and 1:8 of Molar ratio Er/Yb were fabricated respectively.The maximium effective absorption coefficient of the sample 2 at the pump wavelengh 976 nm is 2 dB/m.The attenuation spectral and fluorescence characteristic were discussed..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 339 (2009)
Preparation Theory for Graded Index Polymer Optical Fiber Used in Communication
SONG Hai-jun, WANG Xue-zhong, and ZHAO Wei
The preparation method for graded index polymer optical fiber was analyzed using co-extrusion methods.According to the calculation theory about two refractive index and the function of refractive index distribution of the GI-POF,the dopants′ mass was calculated.Based on the unstable diffusion theory and finite differenThe preparation method for graded index polymer optical fiber was analyzed using co-extrusion methods.According to the calculation theory about two refractive index and the function of refractive index distribution of the GI-POF,the dopants′ mass was calculated.Based on the unstable diffusion theory and finite difference method,the forming of refractive index distribution was described and the mathematical model was obtained.The general approximate way to describe the forming of refractive index distribution of the GI-POF was attained..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 343 (2009)
Detecting and Locating Method of Distributed Optic-fiber Sensing System Based on Sagnac/Mach-Zehnder Interferometers
WU Jun, CHEN Wei-min, TAN Jing, and ZHANG Peng
A 3 × 3 coupler demodulation algorithm was used to detect destruction along the fiber.Based on confirming the occurring of the destruction,by switching the broadband to narrowband source,Mach-Zehnder interference system works.The cross-correlation method was used to realize precise positioning,thus achieving the gA 3 × 3 coupler demodulation algorithm was used to detect destruction along the fiber.Based on confirming the occurring of the destruction,by switching the broadband to narrowband source,Mach-Zehnder interference system works.The cross-correlation method was used to realize precise positioning,thus achieving the goal that defenders are led to stop acts of sabotage to prevent the occurrence of malice.The optical path was presented,and the detecting and locating principle was analyzed in detail..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 347 (2009)
Overlapping Caused by Fourier Transformation Profilometry Based on Tow-frequency Grating
QIAO Nao-sheng, ZHAO Hua-jun, YAO Chun-mei, CAI Xin-hua, and PENG Guang-han
The possibility of frequency overlapping was discussed when the Fourier transformation of deformed fringe for discontinuous object that contain mutation was executed by the method of dual-frequency grating.The condition of separation between f1 of low frequency grating and f2 of high frequency grating was deduced,and fThe possibility of frequency overlapping was discussed when the Fourier transformation of deformed fringe for discontinuous object that contain mutation was executed by the method of dual-frequency grating.The condition of separation between f1 of low frequency grating and f2 of high frequency grating was deduced,and frequency overlapping of the same grating because of the nonlinearity of detector was analyzed.For the overlapping between f1 and f2 is the chief condition,computer simulation and experiment on the condition prove that f1 and f2 are overlapped when f2<2f1,f1 and f2 are separated when f2>2f1..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 356 (2009)
New Scheme of Reflection Volume Holographic Storage Angle-multiplexing
YUE Feng, ZHAO Ye-quan, SHEN Yan, JIA Bao-shen, and YU Sheng-jie
The principle of reflection volume holographic storage technology was introduced.A new reflection holographic sonrage beam path that was different from conventional transmission beam path was designed and established.Based on this principle,a new angle-multiplexing scheme was suggested,which was two-lens confocal methoThe principle of reflection volume holographic storage technology was introduced.A new reflection holographic sonrage beam path that was different from conventional transmission beam path was designed and established.Based on this principle,a new angle-multiplexing scheme was suggested,which was two-lens confocal method.Two thousand holographic images were stored continuously in a signal-point using this system.This method was performed experimentally that been controlled easier and finishing images memory continuously.And it achieved high diffraction efficiency and improved the quality of images.The tow-lens confocal scheme decreased the complexity of system and conldbe multiplexed with high-accuracy.It expands multiplexing dimension from one to two and increases memory density..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 361 (2009)
Physical Optics
Phase Plates for Beam Smoothing Based on the Random Input
YANG Chun-lin, XU Qiao, and WEN Shen-lin
The model that the laser beam with random phase aberration propagates through the beam smoothing phase plate has established.Using the random theory,the characteristics of the transmission light from the phase plate were studied.And the statistic mean value and the variance of the far field distribution were calculatedThe model that the laser beam with random phase aberration propagates through the beam smoothing phase plate has established.Using the random theory,the characteristics of the transmission light from the phase plate were studied.And the statistic mean value and the variance of the far field distribution were calculated.The analysis results show that the relationship of the phase plate’s Fourier spectral T(f)2 and the far field distribution variance is in direct ratio.That means with the increase of the width of T(f)2 the far field distribution of the beam become smoother.The stimulated annealing method was employed to design two different phase plates for beam smoothing.And the numerical results approve the theoretic conclusion..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 382 (2009)
Joint Transform Correlator Based on Chirp Modulation and Slantwise Parallel Wave Illumination Power Spectrum
DENG Xiao-peng
Aiming at shortcoming of classic joint transform correlator,a joint transform correlator based on chirp modulation and slantwise parallel wave illumination the power spectrum was presented,which resultsed in enhanced correlation peaks with chirp modulation of input image and centralizing relative correlation peaks by sAiming at shortcoming of classic joint transform correlator,a joint transform correlator based on chirp modulation and slantwise parallel wave illumination the power spectrum was presented,which resultsed in enhanced correlation peaks with chirp modulation of input image and centralizing relative correlation peaks by slantwise parallel wave illumination the power spectrum.The method did not need digital process with computer and was real-time.The theoretical analysis and experiment results show that better peaks and only one relative correlation peak on the detector are obtained,which improve greatly recognition ability and make use of detector and input plane..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 387 (2009)
Quantum Optics
Two-qubit Quantum State Controlled by Ultra-short Pulse
ZHANG Xiao-dong, and YU Xiang-yang
The semi-classical theory of the interaction between light and matter was applied to the study of the interaction of ultra-short pulse with the two two-level system.A comparison was made between the independent double path-ways(IDPW) and the coherent double path-ways(CDPW) driven in different ways.It is suggested that The semi-classical theory of the interaction between light and matter was applied to the study of the interaction of ultra-short pulse with the two two-level system.A comparison was made between the independent double path-ways(IDPW) and the coherent double path-ways(CDPW) driven in different ways.It is suggested that compared with single qubit,the two-qubits shows a higher property of coherence when interacted with the ultra-short pulse.This property of coherence is related to the initial state of the system,the detuning,and the driving path-ways.And,it is demonstrated that with the presented model quantum state operation can be made through the modulation of the pulse area..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 418 (2009)
QBER Modeling and Simulation of QKD in Optical Fiber with Force
PEI Chang-xing, HAN Bao-bin, ZHAO Nan, LIU Dan, and YAN Yi
The theoretical model of QBER (Quantum Bit Error Rate) was established with POVM (Positive Operator Valued Measurement).PANDA fiber as an example was simulated based on the model.The research results show that under the same angle,bit error rate (BER) increases with increase of force amplitude; and BER increases with iThe theoretical model of QBER (Quantum Bit Error Rate) was established with POVM (Positive Operator Valued Measurement).PANDA fiber as an example was simulated based on the model.The research results show that under the same angle,bit error rate (BER) increases with increase of force amplitude; and BER increases with increase of angle,under the same force without the consideration of 0 and π/2.For normalized force less than 0.4 or the angle less than π/12,the BER could be lower than 5%..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 422 (2009)
Statistical Propertities of Excited Entangled Coherent States
ZHANG Ke-fu, and WANG Zhong-jie
A new kind of entangled coherent states-excited entangled coherent states was obtained by acting boson inverse operators on some mode of entangled coherent states.The result shows that the new states are eigenstates of the 2k-th power of the annihilation operator.Because of the entanglement between the modes of the fieA new kind of entangled coherent states-excited entangled coherent states was obtained by acting boson inverse operators on some mode of entangled coherent states.The result shows that the new states are eigenstates of the 2k-th power of the annihilation operator.Because of the entanglement between the modes of the field,the mean number of mode a increased,and the mean number of mode b changed by photon-adding.After adding photons,sub-poissonian photon statistics and violation of the Cauchy-Schwatz inequality of the fields can be enhanced obviously,but the degree of intermode anticorrelation was weakened by the photon excitations..
Acta Photonica Sinica
- Publication Date: Aug. 25, 2021
- Vol. 38, Issue 2, 425 (2009)
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