Contents
2013
Volume: 33 Issue 9
52 Article(s)
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Atmospheric Optics and Oceanic Optics
Simulation Research on Non-Line-of-Sight Atmospheric Propagation in Fog Weather
Lin Yong, Xu Zhiyong, Wang Jingyuan, Song Chao, Wang Rong, and Chen Yiwang
The multiple scattering propagation model with Monte Carlo method is established, and characteristics in non-line-of-sight (NLOS) atmospheric scattering optical communication channel in fog weather are simulated and analyzed by using the model. The absorption loss for visible light or infrared light is relatively low iThe multiple scattering propagation model with Monte Carlo method is established, and characteristics in non-line-of-sight (NLOS) atmospheric scattering optical communication channel in fog weather are simulated and analyzed by using the model. The absorption loss for visible light or infrared light is relatively low in atmosphere, and the Rayleigh scattering effect generated when visible light or infrared light barges up against air molecules can be ignored. At the same time, there will be a strong Mie scattering effect that occurs between the signal photon in visible light or infrared light wave band and fogdrop particles, so the visible light or infrared light is generally used in long distance scattering optical communication systems. The wavelength selected in simulation is 620 nm, and the relationship between transmission loss and visibility is analyzed in different communication distances in fog weather. The results demonstrate that there will be a visibility that can makes transmission loss lower when the communication range, the elevation angle, the transmitting beam-width divergence and the field-of-view are determined..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 901001 (2013)
Detectors
A Gaussion Mixture PHD Filter for Group Targets Tracking Based on Ellipse Random Hypersurface Models
Zhang Hui, Xu Hui, Wang Xueying, and Wang Tiebing
Tracking group targets is one of the major challenges in modern ballistic missile defense system. These targets not only move in an analogue pattern but also are adjacent in space. The projections of group targets on the focal plane array are no longer points but clusters instead, according to the characterization and Tracking group targets is one of the major challenges in modern ballistic missile defense system. These targets not only move in an analogue pattern but also are adjacent in space. The projections of group targets on the focal plane array are no longer points but clusters instead, according to the characterization and resolution of the infrared optic sensors. Thus the traditional multi-target tracking methods based on the assumption that each target generates at most one measurement are not fitted any more. In order to realize the group targets tracking, a new filter is proposed. The group targets are treated as a union and the extension of the group is described by an ellipse random hyersurface model. Combined with the Gaussian mixture probability hypothesis density (PHD) filter for extended targets, the group targets are tracked by its centroid states and extensions. With comparisons of the Gaussian inverse Wishart PHD based on the random matrix, the proposed method outperforms the latter one in extension estimation as well as centroid state estimation..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 904001 (2013)
Fiber Optics and Optical Communications
Acoustic Detection Technology Based on Fiber Bragg Grating Fabry-Perot Interferometer in Liquid Medium
Zhang Weichao, Zhao Hong, Liu Tong, Wang Guoli, and Li Ruihai
Combining with fiber Bragg grating Fabry-Perot interferometer (FBG-FPI) with cylinder oscillator coupling technology, a highly sensitive sensor is designed for detecting acoustic signal in liquid dielectrics of electrical equipment. A fiber Bragg gratting (FBG) with reflectivity of 50% is cut in the middle to produce tCombining with fiber Bragg grating Fabry-Perot interferometer (FBG-FPI) with cylinder oscillator coupling technology, a highly sensitive sensor is designed for detecting acoustic signal in liquid dielectrics of electrical equipment. A fiber Bragg gratting (FBG) with reflectivity of 50% is cut in the middle to produce two identical half-length Bragg gratings, and a piece of 20-mm SMF-28 monomode fiber is spliced between the FBGs to produce the FBG-FPI. The parameters of the cylinder oscillator are determined for high sensitivity by finite element analysis method based on the theory of elasticity. A novel method of temperature compensation using a tunable distributed feedback (DFB) laser is presented to solve FBG-FPI static working point drift influenced by temperature change. The effect of temperature compensation is proved by raising and falling temperature experiment. A contrast system with FBG-FPI sensor and RC6500T transducer is designed and constructed. The experimental results show that FBG-FPI in liquid dielectrics has the same sensitivity as acceleration transducer for the 1.1 kHz acoustic signal..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906001 (2013)
Analysis of the Correlation of Optical Multiple-Input Multiple-Output Channel Using White LED Lighting in Indoor Line of Sight Environments
Fu Hongshuang, and Zhu Yijun
Visible light communication is a burgeoning technology that uses the visible spectrum for high-speed short-range data communications. Intensity modulation/direct detection is predominantly used in optical wireless in which white LEDs serve as transmitters, neglecting frequency and phase of signal. Therefore correlationVisible light communication is a burgeoning technology that uses the visible spectrum for high-speed short-range data communications. Intensity modulation/direct detection is predominantly used in optical wireless in which white LEDs serve as transmitters, neglecting frequency and phase of signal. Therefore correlation in optical channel is much larger than that in radio frequency channel. The factors which influence the correlation of the optical multiple-input multiple-output (MIMO) channel are analyzed, and the way these factors influence the channel correlation is validated through simulation. According to the mutual influence of signal-to-noise rate and channel correlation, optimal parameters can be obtained in specific scene for optimal bit error rate..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906002 (2013)
Photoluminescence Spectra of the CdSe/ZnS Quantum Dot Doped Polymethylmethacrylate Material
Cheng Cheng, and Wu Ziqi
By adding CdSe/ZnS (core/shell) quantum dots (QDs) into polymethylmethacrylate (PMMA), (CdSe/ZnS)/PMMA QDs doped fiber material is prepared. The absorption-emission spectra and the refractive index of (CdSe/ZnS)/PMMA are measured in respect of doping concentrations. Comparing with the case of the QDs dissolved in n-hexBy adding CdSe/ZnS (core/shell) quantum dots (QDs) into polymethylmethacrylate (PMMA), (CdSe/ZnS)/PMMA QDs doped fiber material is prepared. The absorption-emission spectra and the refractive index of (CdSe/ZnS)/PMMA are measured in respect of doping concentrations. Comparing with the case of the QDs dissolved in n-hexane, the absorption-emission peak wavelengths of the (CdSe/ZnS)/QDs are identical with PMMA substrate. In the doping concentration range 0.013~0.130 mg·mL-1, the observed photoluminescence (PL) peak intensity shows a single peak and follows an exponential square law. As the doping concentration increases, the refractive index increases by 0.0013 at room temperature, and the PL peak wavelength appears a red shift. The maximum red shift is limited by Stokes shift, likely to be related with re-absorption/excitation effect and concentration effect of QDs..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906003 (2013)
Performance Analysis of Multi-Hop Free Space Optics over Strong Turbulence
Hu Qingsong, Huang Yuhua, Wang Junbo, Zhang Jing, Jiang Peng, Su Qin, and Song Xiaoyu
The performance of multi-hop free space optics (FSO) is investigated using serial decode-and-forward (DF) relay transmission. While researching the optical channel fading model, a statistical model for the optical intensity fluctuation at the receiver due to the combined effects of strong turbulence-induced fading, misThe performance of multi-hop free space optics (FSO) is investigated using serial decode-and-forward (DF) relay transmission. While researching the optical channel fading model, a statistical model for the optical intensity fluctuation at the receiver due to the combined effects of strong turbulence-induced fading, misalignment error and pass loss is presented. For given weather and misalignment conditions, the end-to-end outage probability of serial DF multi-hop FSO is derived and a closed-form analytical expression is got. Numerical results show that the serial DF multi-hop transmission is a promising technology to increase the performance of FSO. The derived analytical expression shows excellent agreement with the simulation results..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906004 (2013)
Design and Development of Fiber-Optic Parametric 2R Regenerators
Ma Huidong, Wu Baojian, Wen Feng, Zhou Xingyu, and Xu Bo
The operating principle and design criterion of fiber-optic parametric 2R (re-amplification, re-shaping) regenerator (FOPR) are described based on data-pump solutions. A FOPR is designed by simulation from degenerate four-wave mixing (FWM) pump bandwidth, wavelength configuration of the probe continuous wave, and powerThe operating principle and design criterion of fiber-optic parametric 2R (re-amplification, re-shaping) regenerator (FOPR) are described based on data-pump solutions. A FOPR is designed by simulation from degenerate four-wave mixing (FWM) pump bandwidth, wavelength configuration of the probe continuous wave, and power transfer function (PTF), and the necessity of using the power control unit in FOPRs to improve regenerator performance is also pointed out. Then, an all-optical 2R regenerator is developed and the experimental measurement for the regenerability is done. The measurement results show that, the PTF slope is about 1.7 with the extinction ratio (ER) improvement of about 5 dB, and the experimental data are consistent with the simulation results..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906005 (2013)
Free-Space All-Optical Router with Polarization Structure Based on Crossbar Electro-Optic Switch Network
Xu Jun, Zhi Yanan, Hou Peipei, Sun Jianfeng, Zhou Yu, and Liu Liren
A generalized non-blocking free-space all-optical router with polarization structure based on the crossbar switch network is designed. Electro-optic switch is used as the beam polarization controller and the polarization beam splitter is used as beam-separating element. Basic structures of the 2×2 and 3×3 allA generalized non-blocking free-space all-optical router with polarization structure based on the crossbar switch network is designed. Electro-optic switch is used as the beam polarization controller and the polarization beam splitter is used as beam-separating element. Basic structures of the 2×2 and 3×3 all-optical routers are proposed. They can achieve generalized non-blocking connection between any two channels in free-space and realize the extension of the N×N all-optical router. The novel free-space all-optical router is simple and reliable. It has the advantages of fast response, non-blocking, and high speed. It is easy to realize the programmable logic controller (PLC) control function. It is suitable for air-space all-optical routing network. The experimental verification of the free-space 2×2 all-optical router is implemented and 2×2 optical interconnection is realized. The extinction ratio is 27 dB and the maximum insertion loss is 0.73 dB..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906006 (2013)
Optical Parametric Amplifier at 1 μm Based on Photonic Crystal Fiber
Wang Xiaojian, Yang Sigang, Chen Hongwei, Chen Minghua, and Xie Shizhong
Based on a photonic crystal fiber (PCF) with zero-dispersion wavelength of about 1020 nm, fiber optical parametric amplifier (OPA) is investigated in detail. In order to obtain sufficient parametric gain in a rather short length of fiber, a passively mode-locked ytterbium fiber laser is built up to act as the pump seedBased on a photonic crystal fiber (PCF) with zero-dispersion wavelength of about 1020 nm, fiber optical parametric amplifier (OPA) is investigated in detail. In order to obtain sufficient parametric gain in a rather short length of fiber, a passively mode-locked ytterbium fiber laser is built up to act as the pump seed, and pulse with high peak power is utilized to pump. The amplified short pulse from the mode-locked fiber laser is launched into the PCF to pump. Once the pump central wavelength approaches the zero-dispersion wavelength, significant parametric gain can be observed. The evolutions of parametric gain spectra versus different pump powers and pump wavelengths are investigated. The maximum parametric gain reaches 23 dB from experiment..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906007 (2013)
Opto-Mechanical Structure Design of the Space Optical Hybrid Based on Space Coherent Laser Communication
Zheng Yang, Jiang Huilin, Tong Shoufeng, Zheng Jianping, and He Wenjun
A new style space optical hybrid is designed for intersatellite coherent laser communication. Based on traditional principle scheme of the space optical hybrid, a phase compensation crystal is added. Two 1/2 wave plates are removed. Two polarization splitting prisms are rotated by a certain angle so as to remove the efA new style space optical hybrid is designed for intersatellite coherent laser communication. Based on traditional principle scheme of the space optical hybrid, a phase compensation crystal is added. Two 1/2 wave plates are removed. Two polarization splitting prisms are rotated by a certain angle so as to remove the effect of phase delay due to processing errors of the 1/2 wave plates. The mathematical relationship between phase compensation crystal rotation angle and relative phase difference compensation amount is researched. A phase detection method of the space optical hybrid is proposed. The detection method is used to build experiment and the validity of the phase compensated crystal is proved by experimental data. Mechanical structure of the new style space optical hybrid is designed. The device can be applied to the space coherent receiving system..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906008 (2013)
Transmission Characteristics of Elliptical Terahertz Hollow Fiber with Dielectric and Metallic Inner Coatings
Yu Zhuzheng, Tang Xiaoli, Wang Xinran, and Shi Yiwei
Adding dielectric coatings inside the metallic hollow fibers (MHF) is an effective way to reduce the transmission loss. Effects of dielectric coatings on the transmission characteristics of elliptical MHF in the terahertz region are numerically investigated by using finite element method. The dielectric coating changesAdding dielectric coatings inside the metallic hollow fibers (MHF) is an effective way to reduce the transmission loss. Effects of dielectric coatings on the transmission characteristics of elliptical MHF in the terahertz region are numerically investigated by using finite element method. The dielectric coating changes the transmission modes in the elliptical MHF. Transmission characteristics of the elliptical hollow fiber vary periodically with the frequency owing to the interference effect of the dielectric coating. With the dielectric coating, the elliptical hollow fiber has a longer cutoff wavelength, broader single-mode bandwidth, higher coupling efficiency to the incoming light, and smaller transmission loss. However, it reduces the modal birefringence in the low-loss transmission windows. The results provide an important reference for the fiber design, structure optimization, and fabrication techniques..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906009 (2013)
Design and Optimization of Mode Differential Group Delay for Few-Mode Fiber
Xie Yiwei, Fu Songnian, Zhang Hailiang, Tang Ming, Shen Ping, and Liu Deming
In mode division multiplexing (MDM) transmission system using few-mode fiber (FMF), mode differential group delay (MDGD) is one of the key factors that influence the system performance. Considering the practical fiber fabrication technique, the MDGD characteristics between different modes of step-index (SI) fiber, gradIn mode division multiplexing (MDM) transmission system using few-mode fiber (FMF), mode differential group delay (MDGD) is one of the key factors that influence the system performance. Considering the practical fiber fabrication technique, the MDGD characteristics between different modes of step-index (SI) fiber, graded-index (GI) fiber, trench-assisted SI fiber, and trench-assisted GI fiber are numerically investigated. Under the condition of supporting four modes, two optimized refractive index profiles of FMFs with high and low MDGDs are presented. The high MDGDs of LP11, LP12, LP02 versus LP01 are 4.65, 10.02, 11.73 ps/m, respectively; while low MDGDs of LP11, LP12, LP02 versus LP01 are -0.049, -0.258, -0.168 ps/m, respectively. We fabricate and characterize the FMF with a SI profile, whose loss of fundamental mode is 0.23 dB/km at 1550 nm and 0.37 dB/km at 1310 nm. The measurement and analysis results indicate that it can be used for future MDM transmission system..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906010 (2013)
Ridge Regression Approach of Electrical Blind Equalization for Optical Communication Channel
Ruan Xiukai, Zhang Yaoju, Tan Yanhua, and Wu Ping
To avoid the coefficient matrix ill-conditioned problem, and reduce the heavily reliance on data length of those least mean square/least square (LMS/LS) blind equalization algorithms, a novel electrical blind equalization algorithm of optical communication systems is presented by using ridge regression(RR) approach. ByTo avoid the coefficient matrix ill-conditioned problem, and reduce the heavily reliance on data length of those least mean square/least square (LMS/LS) blind equalization algorithms, a novel electrical blind equalization algorithm of optical communication systems is presented by using ridge regression(RR) approach. By constructing a novel cost function of RR blind equalization, the blind equalization problems are transformed into solving an unconstrained optimization problem and the process of how to get the equalizer is shown. Meantime, a batch processing iterative method is constructed to solve this special optimization problem. Then the influence of ridge factor λ value of RR blind equalization algorithm and the algorithm complexity on the cost function and its property are analyzed. The proposed approach can place M-ray phase shift keying (MPSK) and quadrature amplitude modulation (QAM) modulation modes in a single, unified algorithm framework. Finally, simulation results verify that the performance of the proposed algorithm is superior to those existing LMS/LS blind equalization algorithms..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906011 (2013)
Improved Carrier Phase Estimation Algorithm Based on Linear Phase Interpolation
Zhong Kangping, Li Tangjun, Sun Jian, Jia Nan, and Wang Muguang
An improved carrier phase estimation (CPE) algorithm based on linear phase interpolation (LPI) is proposed, and simulation and experiment are conducted for evaluating the performance of the proposed algorithm in a 112 Gb/s dual-polarization 16-ary quadrature amplitude modulation (DP-16QAM) system. A LPI function is useAn improved carrier phase estimation (CPE) algorithm based on linear phase interpolation (LPI) is proposed, and simulation and experiment are conducted for evaluating the performance of the proposed algorithm in a 112 Gb/s dual-polarization 16-ary quadrature amplitude modulation (DP-16QAM) system. A LPI function is used to deal with the obtained estimated phase noise in the algorithm based on CPE of block averaging for significantly improving the accuracy of CPE. Compared with the normal block averaging method, the variance of estimated phase error of the proposed algorithm is reduced by 26%, and the linewidth tolerance is 2 times compared with the algorithm based on block averaging. For a 112 Gb/s DP-16QAM experimental system, at 3.8×10-3 bit error rate (BER), a 0.7 dB reducement in terms of the required optical signal-to-noise ratio (OSNR) is demonstrated using the proposed algorithm based on CPE algorithm with respect to the normal block averaging algorithm. The performance of the proposed algorithm is comparable to the algorithm based on sliding window. However, hardware complexity is reduced by 99.2% in comparison with the algorithm based on sliding window..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906012 (2013)
Investigation of All Optical 2R Regeneration Based on Semiconductor Optical Amplifier
Chen Xin, Lou Caiyun, Wang Qiang, Zhao Xiaofan, Yu Wenke, and Huo Li
Power transfer function of a 40-Gb/s 2R (re-amplification and reshaping) regenerator consisting of a semiconductor optical amplifier (SOA) and a delay interferometer (DI) is culculated numerically, and the regeneration performance of the SOA-DI optical gate for the degraded signals at 10~40 Gb/s is experimentally invesPower transfer function of a 40-Gb/s 2R (re-amplification and reshaping) regenerator consisting of a semiconductor optical amplifier (SOA) and a delay interferometer (DI) is culculated numerically, and the regeneration performance of the SOA-DI optical gate for the degraded signals at 10~40 Gb/s is experimentally investigated. Because the cross gain modulation (XGM) effect in a SOA depends on the carrier recovery time, inverted logical signal based on XGM experiences severe pattern effect at XGM-SOA-cross gain compression (XGC) regenerator. A novel all-optical 2R regeneration scheme by combining the transient cross phase modulation and XGC effects in SOA is proposed and it successfully demonstrates all-optical 2R regeneration for 100-Gb/s return-to-zero (RZ) signal..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 906013 (2013)
Geometric Optics
Description of Interference Theory on Generated Period Bottle Beam by Focus Non-Diffracting Beams
Du Tuanjie, Wu Fengtie, Wang Tao, Li Pan, Li Dong, and He Xi
Description of interference theory on generated period bottle beam by focus non-diffracting beams is used. The biggest non-diffracting distance of bottle beam is calculated. The non-diffracting beam focused by axicon is analyzed by geometrical optics theory and interference theory. The intensity distributions along theDescription of interference theory on generated period bottle beam by focus non-diffracting beams is used. The biggest non-diffracting distance of bottle beam is calculated. The non-diffracting beam focused by axicon is analyzed by geometrical optics theory and interference theory. The intensity distributions along the propagation distance, the intensity evolution of the bottle beams in a complete period and the corresponding spot diagram are simulated by the MathCAD software. In terms of experiments, non-diffracting Bessel beam is generated by an axicon with base angle of 1°, and then is focused by another axicon with base angle of 2°. The beam is observed by a microscope and is photographed by a CCD camera. The experimental results are agree well with theoretical analysis..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 908001 (2013)
Optical System Generating Wide Measurement Area and Low Divergence Degree Grating Structure Light
Wu Zhiwei
A novel optical system is proposed, and it is composed of two biprisms with different bottom corners and one cylindrical lens. The technical problem that the striped regional of grating structure light generating by single biprism is so small that it cannot be applied to wide range measurement is solved. Physical proceA novel optical system is proposed, and it is composed of two biprisms with different bottom corners and one cylindrical lens. The technical problem that the striped regional of grating structure light generating by single biprism is so small that it cannot be applied to wide range measurement is solved. Physical processes of generating grating structure light is analyzed by geometrical optics, and relevant parameters are also calculated. The intensity distribution in different positions after system is simulated by Zemax software, and the intensity distribution with the change of system parameters, e.g. structure parameters of optical elements and relative position between optical elements, are also analyzed. The conclusion of simulation is consistent with that of geometrical optics theory. The result shows that when a plane wave illuminates on the novel optical system, the grating structure light with wide measurement area, low divergence degree and adjustment flexibulity is formed..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 908002 (2013)
Holography
Holographic Waveguide Head-Mounted Display System Design Based on Prisms-Grating Structure
Zeng Fei, Zhang Xin, Zhang Jianping, Shi Guangwei, Qu Hemeng, and Zhang Jizhen
In order to enhance the optical efficiency, splitting prisms and holographic gratings are used to expand the exit pupil. And double-grating design is used to enhance the image quality. By modeling the system with optical design software, the optical quality is analyzed and simulated. The system has a field of view (FOVIn order to enhance the optical efficiency, splitting prisms and holographic gratings are used to expand the exit pupil. And double-grating design is used to enhance the image quality. By modeling the system with optical design software, the optical quality is analyzed and simulated. The system has a field of view (FOV) of 20°×20°and an exit pupil of 20 mm×20 mm. The residual wave aberration is less than 0.075λ, the distortion is less than 0.01%, and the modulation transfer function close to the diffraction limit. For the zero FOV, the exit pupil has uniform irradiance distribution with an optical efficiency of 5%~6%. For the FOV of 20°, the irradiance uniformity drops down slightly, and the optical efficiency is 3%~4%. The simulated results show that the holographic waveguide system dramatically improves the optical efficiency of the holographic waveguide head-mounted display (HMD) system. Also the prisms waveguide optical system is highly practical and can be applied to the new generation HMD technology..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 909001 (2013)
Imaging Systems
Compensation Using Clocking Lens Elements in High Imaging Performance Optical Systems
Liu Chunlai, Huang Wei, Shang Hongbo, Xu Weicai, and Yang Wang
In the manufacturing process of high imaging performance lenses, the errors of the surface figure and the material homogeneity make it hard to realize extremely-small aberration lenses. Lots of compensation strategy must be applied and the lens elements clocking is an essential one. A clocking algorithm that can figureIn the manufacturing process of high imaging performance lenses, the errors of the surface figure and the material homogeneity make it hard to realize extremely-small aberration lenses. Lots of compensation strategy must be applied and the lens elements clocking is an essential one. A clocking algorithm that can figure out the right angle of lens is proposed and the validity of the algorithm is proved by an experiment, it also shows that clocking is a potential strategy of wavefront compensation. A principle that can be used to judging the compensability of a lens and selecting optical material is proposed. At the end of the paper, a method of modeling multi-field optical system for clocking compensation is proposed, and the analysis result of optical design software proves that it′s useful. Clocking is an effective and economic compensation method in high performance lens manufacturing process, and it is meaningful for image performance improving..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 911001 (2013)
Research on the Repeatable Pseudo-Thermal Light Based on Random Phase Plate Scanning
Jiao Jia, Zhao Chengqiang, Cui Lijun, and Xu Wendong
To solve the problem that the imaging speed is limited by the reference arm acquisition in remote sensing experiment based on correlated imaging, a repeatable pseudo-thermal light based on random phase plate scanning is proposed. The repeatable laser speckles are produced so that reference arm acquisition is not necessTo solve the problem that the imaging speed is limited by the reference arm acquisition in remote sensing experiment based on correlated imaging, a repeatable pseudo-thermal light based on random phase plate scanning is proposed. The repeatable laser speckles are produced so that reference arm acquisition is not necessary in imaging process. Repeatability evaluation function is established and the influence of repeatability on image quality are numerically analyzed. Laser intensity jitter and positioning accuracy are pointed out to make sure that the image quality is not affected. The performance of the repeatable pseudo-thermal light is verified, and at the emission velocity of 4000 frames/s, the correlation coefficient can reach more than 0.97 with intensity jitter and positioning accuracy satisfying. The feasibility of the repeatability of pseudo-thermal light is approved and imaging resolution can reach the diffraction limit..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 911002 (2013)
Sparsity-Based Ghost Imaging with Gaussian-Amplitude Modulation
Chen Jie, Bo Zunwang, and Han Shensheng
With the controllability of the digital micromirror device (DMD), a single-arm ghost imaging experiment platform based on the DMD amplitude modulation is built and DMD amplitude modulation is used to generate prebuilt quasi-Gaussian random measurement matrix with different mean values and standard deviations. The influWith the controllability of the digital micromirror device (DMD), a single-arm ghost imaging experiment platform based on the DMD amplitude modulation is built and DMD amplitude modulation is used to generate prebuilt quasi-Gaussian random measurement matrix with different mean values and standard deviations. The influence of the quasi-Gaussian random measurement matrix with different mean values and standard deviations and the image′s sparsity on the quality of image reconstruction based on ghost imaging via sparsity constraints (GISC) is experimentally analyzed. Both the numerical simulation and experimental results show that: as the mean value u decreases or the standard deviation σ increases (namely as the size of amplitude modulation δ=σ/u of the quasi-Gaussian random measurement matrix A increases), the reconstruction fidelity of GISC is proportion to δ-1/2, and at the same time, it is linearly related to the image′s sparsity β..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 911003 (2013)
Instrumentation, Measurement and Metrology
Boresight Error Analysis and Correction of Conformal Infrared Seeker
Wang Chao, Jiang Huhai, Zhu Ruifei, Yu Linyao, Zhang Tianyi, Wei Qun, and Jia Hongguang
Infrared conformal seeker has demonstrated its capabilities as a prominent technique for the supersonic characteristic. To achieve the potential accuracy of target tracing, boresight error should be corrected as a result of using aspheric and quadric surfaces in conformal optics system. This paper describes boresight eInfrared conformal seeker has demonstrated its capabilities as a prominent technique for the supersonic characteristic. To achieve the potential accuracy of target tracing, boresight error should be corrected as a result of using aspheric and quadric surfaces in conformal optics system. This paper describes boresight error measurement and correction in conformal infrared seeker. Expression and correlation coefficient of boresight error along with field of regard (FOR) ranging from 0° to 20° are obtained using ray tracing simulation. Boresight error measurement has been accomplished by correlation matching method, and results illuminate that the relative error is 5.02%. Error correction model by unitary nolinear regression analysis is introduced. The experimental results have demonstrated that boresight error is reduced to lower than 30 μm and tracking accuracy is improved to ±1 pixel. The results can meet the precision requirement of servo control system and provide part of the basis for optics system optimization..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912001 (2013)
High Frequency and High Accuracy Laser Ranging System Based on Double Thresholds Leading-Edge Timing Discrimination
Chen Ruiqiang, Jiang Yuesong, and Pei Zhao
The laser ranging system with hundreds of kilohertz measuring frequency and sub-centimeter level accuracy is one of the hotspots in the research of laser ranging. The principle and method of realizing laser ranging system are analyzed based on picosecond pulsed laser. According to the utmost narrow pulse width, the metThe laser ranging system with hundreds of kilohertz measuring frequency and sub-centimeter level accuracy is one of the hotspots in the research of laser ranging. The principle and method of realizing laser ranging system are analyzed based on picosecond pulsed laser. According to the utmost narrow pulse width, the method of double thresholds leading-edge timing discrimination and width control method of digital signal generated by voltage comparator are applied. Coupled with high accuracy time to digital chip TDC-GPX, it can achieve the requirement of system. Experiments show that the system is stable and reliable, the measuring frequency can be up to 500 kHz, and the ranging accuracy is between 4 mm and 10 mm..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912002 (2013)
Spatial Carrier Speckle Interferometry Technique Research Based on Fresnel Bi-Prism
Zhu Meng, Huang Zhanhua, Li Xiangyu, and Li Xiuming
Speckle shearing interferometry is an important tool for dynamic surface deformation measurement, which in combination with spatial phase shift technique can make the method more useful in practice. More attention is paid to the spatial carrier frequency method based on Fresnel bi-prism which can measure the slope of dSpeckle shearing interferometry is an important tool for dynamic surface deformation measurement, which in combination with spatial phase shift technique can make the method more useful in practice. More attention is paid to the spatial carrier frequency method based on Fresnel bi-prism which can measure the slope of deformation instantaneously. The application of Fresnel bi-prism can obtain a spatial carrier speckle interferogram. The shear distance and carrier frequency generated by the bi-prism are analyzed. A slit is used to control the speckle and produce the carrier in one speckle size. The calibration of carrier is implemented by Fourier analysis method, and the sinusoidal fitting method is used for actual measurement of slope. The experiments show that this method can be conveniently used in spatial phase shift speckle interferometry and is suitable for dynamic measurement..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912003 (2013)
New Sub-Aperture Stitching Algorithm Based on Transformation
Chen Yiwei, Wang Fei, Wang Gaowen, Sui Yongxin, and Yang Huaijiang
Sub-aperture stitching algorithm should compensate the mechanical location errors in sub-aperture stitching interferometer because they lead to the relative location errors between sub-apertures which affect the stitching result. In order to improve the compensation ability of sub-aperture stitching algorithm, a new stSub-aperture stitching algorithm should compensate the mechanical location errors in sub-aperture stitching interferometer because they lead to the relative location errors between sub-apertures which affect the stitching result. In order to improve the compensation ability of sub-aperture stitching algorithm, a new stitching algorithm different from the calculation compensator algorithm using original pictures is proposed. The new algorithm transforms original pictures into images beneficial to the calculation of compensator and calculates the location of each sub-aperture using pictures after transformation. It stitches original pictures using the calculated locations. Due to the high location accuracy of the sub-aperture stitching interferometer, the new algorithm transforms original pictures to gradient norm pictures and gradient direction pictures, and calculates the compensator based on direction pictures using norm pictures as weight. The simulation result shows that this algorithm compensates location errors more effectively than the calculation compensator algorithm does. In comparison with full-aperture testing, sub-aperture stitching result demonstrates the validity of this algorithm, and indicates that the method can enhance the location errors compensation ability by choosing a proper transformation..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912004 (2013)
Calibration of Rotating Quarter-Wave Method Based Polarimeter
Tang Feilong, Li Zhongliang, Bu Yang, Wang Xiangzhao, Fan Lili, Wang Xuan, and Cao Shaoqian
The retardation error, the fast axis angle error of wave-plate and the angle error of polarizer are the main error sources of polarimeter based on rotating quarter-wave method. The measurement accuracy can be effectively improved by calibrating the polarimeter. A new simple calibration method of polarimeter is proposedThe retardation error, the fast axis angle error of wave-plate and the angle error of polarizer are the main error sources of polarimeter based on rotating quarter-wave method. The measurement accuracy can be effectively improved by calibrating the polarimeter. A new simple calibration method of polarimeter is proposed. Horizontal linearly polarized light [1,1,0,0]T is used as a standard reference light, and it is measured when the polarizer is fixed on 0° and 45° respectively. The parameter errors of device can be calculated and obtained to calibrate the polarimeter. The experimental results show that the measurement error is reduced by the proposed method from 3% to less than 0.87%..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912005 (2013)
Method of Adjusting the Line Array Direction of the Time Delay Integration CCD
Xing Hui
Time delay integration (TDI) CCD is a kind of CCD with frame structure and linear output, and its charge transfer has certain directivity. Therefore, CCD integal direction and TDI imagery heading must maintain the same. The measuring principle of the theodolite is given, and then the measuring coordinate system is estaTime delay integration (TDI) CCD is a kind of CCD with frame structure and linear output, and its charge transfer has certain directivity. Therefore, CCD integal direction and TDI imagery heading must maintain the same. The measuring principle of the theodolite is given, and then the measuring coordinate system is established. Measuring principle and adjusting method are analyzed for both symmetrical and unsymmetrical field TDI CCD.The formula to calculate the linear array direction is also deduced. The example given at the end indicates the measuring and calculating method is feasible..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912006 (2013)
Full Field Velocity Measurement of Laser-Driven Flyer Using Framing-Imaging Velocity Interferometer System for Any Reflector
Liu Shouxian, Wen Weifeng, Yuan Shuyun, Chen Guanghua, Liu Jun, Peng Qixian, and Li Zeren
A framing-imaging velocity interferometer system for any reflector (VISAR) for measuring the integrity, speed dispersion and planarity of a flyer is developed. Based on the existing line-imaging VISAR, a smaller velocity-per-fringe constant is selected for higher velocity resolution, and a framing camera is used as a sA framing-imaging velocity interferometer system for any reflector (VISAR) for measuring the integrity, speed dispersion and planarity of a flyer is developed. Based on the existing line-imaging VISAR, a smaller velocity-per-fringe constant is selected for higher velocity resolution, and a framing camera is used as a substitute for a streak camera to capture the two-dimensional (2D) interferograms at different time. Full-field velocity map is provided with a spatial resolution of 5 μm and a velocity sensitivity of 15 m/s. The technique is employed to measure a two-dimensional spatial velocity field of Cu (or Al) foils flyer driven by a pulse laser, and to reveal the continuous evolution of flyers. These results demonstrate that the framing imaging VISAR can be a valuable addition to the suite of diagnostics for the flyer planarity study..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912007 (2013)
Variation of Solar Irradiance Absolute Radiometer Cavity Tempreture Response in Vacuum and Its Effect
Yang Zhenling, Fang Wei, Song Baoqi, Luo Yang, and Wang Yupeng
In order to investigate the influence of vacuum environment on the measured value of solar irradiance absolute radiometer (SIAR) and its auxiliary value to the world radiometric reference (WRR), and improve the tracing accuracy of on-orbit solar irradiance measurements to WRR and consistency of measurements of differenIn order to investigate the influence of vacuum environment on the measured value of solar irradiance absolute radiometer (SIAR) and its auxiliary value to the world radiometric reference (WRR), and improve the tracing accuracy of on-orbit solar irradiance measurements to WRR and consistency of measurements of different on-orbit instruments, the variation of cavity tempreture response and its effect of SIAR in vacuum environment are measured and estimated. Since the absence of air convection in vacuum, the time constant of SIAR cavity temperature response becomes longer and the equilibrium temperature becomes higher in the same heating power with that in air, thus the responsibility of SIAR cavity is significantly reduced.The radiometric measurement results of the same target in vacuum and air environment show a relative difference of 0.15% between the measured irradiances since the variation of time constant and responsibility, which causes 0.15% changes in the auxiliary value of radiometric measurements in vacuum to WRR..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912008 (2013)
Diode Laser Absorption Sensor for Measurements of Temperature and Velocity in Supersonic Flow
Wang Guangyu, Hong Yanji, Pan Hu, and Song Junling
Tunable diode laser absorption spectroscopy (TDLAS), as a robust non-contact measurement technology, has exhensive applications in the diagnosis, for harsh environments commonly experienced in combustion and propulsion flows. A tunable diode laser sensor, which is based on water absorption, has been developed to measurTunable diode laser absorption spectroscopy (TDLAS), as a robust non-contact measurement technology, has exhensive applications in the diagnosis, for harsh environments commonly experienced in combustion and propulsion flows. A tunable diode laser sensor, which is based on water absorption, has been developed to measure temperature and velocity in a supersonic ground-test facility simultaneously. Scanned-wavelength direct absorption spectroscopy and calibration-free wavelength modulation spectroscopy are employed to enable the absolute measurement. The sensor is tested at the direct-connect supersonic combustion facility which operates at mass flux of 2.5 kg/s, Mach number of 2.0, total pressure from 5.3 to 5.7 atm (1 atm=1.01325×105 Pa) and total temperature from 1100 K to 1700 K. The measured temperature and velocity agree well with the theoretical model, which validates the efficiency of the sensor design. The investigative results can provide the technique support for engineering applications..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 912009 (2013)
Lasers and Laser Optics
Experimental Observation of a PbSe Nanocrystal Quantum Dot Doped Fiber Laser with Single/Multiple Modes
Cheng Cheng, Bo Jianfeng, and Yan Jinhua
A PbSe nanocrystal quantum dot doped fiber laser (QDFL) is achieved in experiment by doping the PbSe quantum dots (QDs) into the fiber and configuring an all-fiber ring resonator consisting of quantum dot doped fiber (QDF), wavelength division multiplexer (WDM), and fiber Bragg grating (FBG). Upon 980 nm laser diode (LA PbSe nanocrystal quantum dot doped fiber laser (QDFL) is achieved in experiment by doping the PbSe quantum dots (QDs) into the fiber and configuring an all-fiber ring resonator consisting of quantum dot doped fiber (QDF), wavelength division multiplexer (WDM), and fiber Bragg grating (FBG). Upon 980 nm laser diode (LD) pumping, an obvious exciting threshold is observed, i.e., lower than the threshold, no laser appears; higher than it, the laser output increases linearly with the pumping power. The laser output is of multiple modes, while single mode can be selected out by bending fiber technique. Upon pump power of 68 mW inputted into the fiber with 50 μm diameter, the laser output power comes to 19.2 mW (multi-mode) and 6.31 mW (single mode) with linewidth less than 0.1 nm, corresponding to pumping efficiency of 28% and 9.3%, respectively..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 914001 (2013)
Materials
Measurement of Thermal Refractive Index Coefficients of YAl3(BO3)4 Crystal
Zhai Naixia, Liu Lijuan, and Chen Chuangtian
The refractive indices of nonlinear optical crystal YAl3(BO3)4 (YAB) for nine wavelengths of 0.194, 0.254, 0.404, 1.53, 2.325 μm and so on under the temperature range from 40 ℃ to 160 ℃ are measured by the prism minimum deviation method．The Sellmeier equations at different temperatures and the relationship between the The refractive indices of nonlinear optical crystal YAl3(BO3)4 (YAB) for nine wavelengths of 0.194, 0.254, 0.404, 1.53, 2.325 μm and so on under the temperature range from 40 ℃ to 160 ℃ are measured by the prism minimum deviation method．The Sellmeier equations at different temperatures and the relationship between the thermal coefficients of refractive index and the wavelength have been obtained by the least square method. The calculated acceptance temperature for type I phase-matching of YAB crystal for 266 nm ultraviolet light generation is 6.9 ℃·cm based on the above equations. Both the experimental and theoretical values show that YAB crystal may be an ideal nonlinear optical crystal for 266 nm harmonic generation with high power and high stability because of its good thermal stability..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 916001 (2013)
Surface-Plasmon-Polariton Manipulation Using Photonic Crystals
Dong Huiyuan, and Wang Jin
The existence of surface plasmon polaritons (SPPs) at the interface between air/metal-dielectric layered systems is demonstrated. Using the transfer matrix method, we calculate the band structure of periodic metal-dielectric layered system and the dispersion relation of SPPs. It is found that we can effectively tune suThe existence of surface plasmon polaritons (SPPs) at the interface between air/metal-dielectric layered systems is demonstrated. Using the transfer matrix method, we calculate the band structure of periodic metal-dielectric layered system and the dispersion relation of SPPs. It is found that we can effectively tune surface modes by varying the thickness of the top metal layer. Moreover, in the presence of static magnetic field, the time reversal symmetry of systems is broken, and nonreciprocal SPPs can be gotten. In particular, such a system can provide a frequency range where one-way SPPs are allowed..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 916002 (2013)
Microscopy
Microcavity Photoacoustic Detecting Technology and Imaging Method
Cai Qiuxia, Tang Zhilie, Wu Yongbo, Tan Zhiliang, and Zhang Man
Employing microcavity coupling technology, a microcavity photoacoustic transducer with high sensitivity is proposed. The transducer works like this: the photoacoustic (PA) waves, which carry the information of the sample, transmit across the microchannel to the coupling cavity and are detected by the microphone. In theEmploying microcavity coupling technology, a microcavity photoacoustic transducer with high sensitivity is proposed. The transducer works like this: the photoacoustic (PA) waves, which carry the information of the sample, transmit across the microchannel to the coupling cavity and are detected by the microphone. In the same case of the temperature change, the pressure variation in an airtight cavity is inversely proportional to the volume of the cavity. So the sensitivity of transducer can be effectively increased by using the microcavity structure, which is more sensitive to the feeble PA signal induced by a modulated continuous wave laser source. By using the technology, the photoacoustic microscopy (PAM) images of onion epidermal cells and RBCs are clearly reconstructed in cellular resolution. The result of resolution test target verifies the resolution of the PAM with microcavity PA transducer is better than 1.25 μm..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 918001 (2013)
Nonlinear Optics
Line Optical Rogue Waves and Transmission Controlling in Inhomogeneous Nonlinear Waveguides
Zhang Jiefang, and Lou Jihui
Optic pulse propagation in inhomogeneous nonlinear waveguides can be described by nonlinear Schrdinger equation with (3+1) dimension variable coefficients. By using similar transformation, exact two-dimensional 1st-order and 2nd-order optical rogue wave solutions is developed. Moreover, the dynamics of the two-dimensiOptic pulse propagation in inhomogeneous nonlinear waveguides can be described by nonlinear Schrdinger equation with (3+1) dimension variable coefficients. By using similar transformation, exact two-dimensional 1st-order and 2nd-order optical rogue wave solutions is developed. Moreover, the dynamics of the two-dimensional 1st-order and 2nd-order 2-dimensional rogue wave propagation in the waveguides with periodic dispersion are discussed. Finally, manipulating propagate conditions of two-dimensional optical rogue wave is given. Worth while pointing out especially, the formats of both 1-order and 2-order two-dimensional optical rogue wave in transverse section of the media are similar to line soliton of the KP (Kadomfsov-Pefrishvili) equation, so the concept of linear optical rogue wave is proposed in this paper..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 919001 (2013)
Optical Design and Fabrication
Analysis of Mid-Spatial Frequency Surface Errors Effects on Local Flare in Lithographic Projection Lens
Yang Wang, Huang Wei, Xu Weicai, and Shang Hongbo
The influence of mid-spatial frequency surface errors on flare is analysed. Power spectral density function is used to describe the mid-spatial frequency surface errors and analyze the flare. The concepts of spatial frequency and equivalent pupil are used to analyze tolerance. Based on the method, the lens with numericThe influence of mid-spatial frequency surface errors on flare is analysed. Power spectral density function is used to describe the mid-spatial frequency surface errors and analyze the flare. The concepts of spatial frequency and equivalent pupil are used to analyze tolerance. Based on the method, the lens with numerical aperture of 0.75 and working wavelength of 193 nm is analyzed under the requirement of the local flare intensity ratio is less than 0.5% in the scattering range of 2~10 μm. The spatial frequency range of equivalent pupil is 16~78. And it demands that the coefficient of power spectral density is 0.06 and the coefficient of power spectral density is 1.5. The results show that the way can be used to analyze the flare and tolerance the mid-spatial frequency surface errors in lithographic lens..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 922001 (2013)
Optical Design of Prism Spectrometer System with a Small Incident Angle
Chen Yang, and Wang Yueming
The characteristics and principle of prism spectrometer are studied and a new method to design the prism spectrometer system with a small incident angle is proposed. This type of spectrometer uses reflective triplet optical path, so there is no need to add the correcting lens. The system has no aberration caused by theThe characteristics and principle of prism spectrometer are studied and a new method to design the prism spectrometer system with a small incident angle is proposed. This type of spectrometer uses reflective triplet optical path, so there is no need to add the correcting lens. The system has no aberration caused by the chromatic abberation and has excellent imaging quality. The spectral inflection can be corrected effectively. An optical system of imaging spectrometer is designed. The imaging quality is analyzed by using optical design software. The result shows that the modulation transfer function (MTF) of the system at different wavelengths is close to the diffraction limit and the design requirements are fully met..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 922002 (2013)
Nanodots Pattern and Optical Properties of Monocrystalline Silicon Induced by Low Energy Ion Beam
Chen Zhili, and Liu Weiguo
Electron cyclotron resonance (ECR) has been employed to etch the surface of monocrystalline silicon (100) with sample rotation, etching effects and optical properties of low energy Ar+ beams at different ion-beam incident angles are studied. The experimental results indicate that, when ion beam energy is 1000 eV, beam Electron cyclotron resonance (ECR) has been employed to etch the surface of monocrystalline silicon (100) with sample rotation, etching effects and optical properties of low energy Ar+ beams at different ion-beam incident angles are studied. The experimental results indicate that, when ion beam energy is 1000 eV, beam current density is 265 μA/cm2, and etching time is 60 min with simultaneous sample rotation, well ordered self-organized nanodot patterns form on the Si surface. Within 0°～25°, if the incident angle increases, root mean square (RMS) of the roughness and optical transmittance of the sample are enhanced with the growth of self-organizing nano-structure, when surface roughen functions principally. If the incident angle remains increaseing, the reducing size of self-organized nanodots lessen RMS and optical transmittance of samples. If the incident angle continues to increase nearly up to 45°, the dot patterns fade away, and RMS and mean optical transmittance of samples reach the minimums of 0.83 nm and 55.05%, and the polishing effect is obvious for ion beams. If the incident angle further increases, the self-organized dot patterns appear on the sample surface again, RMS is dramatically enlarged and optical transmittance start to magnify with the angle increasing, and at about 65°, the mean optical transmittance get the maximum of 64.59%, then the RMS and optical transmittance begin to decrease slowly with the incident angle increasing. The transformation self-organized nano-structure patterns results from the interaction of spurting roughness and relaxation mechanism..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 922003 (2013)
Research on Ceramic-Glass′s Brittle-Ductile Transition Based on Nano-Indentation Fatigue Experiment
Wang Jinghe, Li Shunzeng, Song Xiaoli, Song Wei, Wang Hongxiang, and Li Shuping
Ceramic-glass is an important material for large space telescopes (LST) and laser gyroscope. But during the ultra precision machining process, surface damages may exist inside the workpiece, which greatly decreases the optical performance of ceramic-glass. Indentation method is utilized to research the critical conditiCeramic-glass is an important material for large space telescopes (LST) and laser gyroscope. But during the ultra precision machining process, surface damages may exist inside the workpiece, which greatly decreases the optical performance of ceramic-glass. Indentation method is utilized to research the critical condition of crack brittle-ductile transition of the ceramic-glass. Based on this, the influences of brittle-ductile transition affected by processing fatigue are investigated by the cycle nano-indentation test, as well as the variation pattern of the glass′s critical pressure under the fatigue condition and the influences of critical grinding depth caused by fatigue factors. Results show that, the grinding cycle process causes the workpiece′s surface accumulating mechanical damage, which leads the decreased fracture toughness of the ceramic-glass material and it′s plastic domain. Results also shows that it is the cycle index that connected with the critical pressure load which cracks the surface of the ceramic-glass: the more the cycle times, the lower the critical pressure load. Besides, the critical grinding conditions of the brittle-ductile transition are determined. Research results provde a certain reference to the improvenent of the optical element surface quality..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 922004 (2013)
Manufacturable Design of 16~22 nm Extreme Ultraviolet Lithographic Objective
Cao Zhen, Li Yanqiu, and Liu Fei
Extreme ultraviolet lithography is one of the promising technologies for 16~22 nm node of lithography. Design of the extreme ultraviolet lithographic projection objective needs not only to meet the demand of imaging quality and resolution but also to consider the manufacturability. Two projection objectives with numeriExtreme ultraviolet lithography is one of the promising technologies for 16~22 nm node of lithography. Design of the extreme ultraviolet lithographic projection objective needs not only to meet the demand of imaging quality and resolution but also to consider the manufacturability. Two projection objectives with numerical apertures of 0.3 and 0.32, respectively, are designed in the 26 mm×1.5 mm exposure area to meet the demands of manufacture, measurement and fabrication. The optical performance and manufacturability of the two projection objectives are analyzed and compared in detail. Combining with the resolution enhancement technology, the two projection objectives can meet the requirements of 22 nm and 16 nm node of lithography..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 922005 (2013)
Other Areas of Optics
Study on Laser Trapping Rayleigh Particles Based on the Nanolens
Liu Zilong, and Zhang Bo
An idea that Rayleigh particles can be captured by replacing the geometry optical lens in the traditional optical tweezers with nano-lens is proposed. We calculate the diffraction field of a plane wave passed through the nano-lens by using the finite difference time domain (FDTD) method and the radiation force acted onAn idea that Rayleigh particles can be captured by replacing the geometry optical lens in the traditional optical tweezers with nano-lens is proposed. We calculate the diffraction field of a plane wave passed through the nano-lens by using the finite difference time domain (FDTD) method and the radiation force acted on the Rayleigh particles in the field based on the point dipole approximation method. The results show that, comparing to best results (focal spot close to the diffraction limit) of conventional optical tweezers, the trapping efficiency, stable trapping zone length and quality factor of the proposed tweezers can be greatly improved. Especially for the two capture zones on the both sides of nano-lens, the trapping efficiency and quality factor can be improved by 2 to 3 orders of magnitude, and also the force of trapped particles has a strong polarization dependence (unlike conventional optical tweezers), which can be used to achieve rotation operation of particles..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 935001 (2013)
Quantum Optics
Measurement of the Noise of Yb-Doped Femtosecond Photonic Crystal Fiber Laser
Gao Kang, Guo Xueshi, Zhao Ningbo, and Li Xiaoying
Lasers with compact size, low cost and low noise are desirable for developing practical non-classical sources. Compared with Tisapphire mode-locked laser, Yb-doped photonic crystal fiber (PCF) based mode-locked laser has the advantages of simple structure, compact size and low cost, but its noise characteristics need tLasers with compact size, low cost and low noise are desirable for developing practical non-classical sources. Compared with Tisapphire mode-locked laser, Yb-doped photonic crystal fiber (PCF) based mode-locked laser has the advantages of simple structure, compact size and low cost, but its noise characteristics need to be further investigated. The noise of an Yb-doped PCF based femtosecond laser is measured and analyzed by a home-made self-homodyne detection system which is suitable for measuring the noise of pulsed laser. The results show that the amplitude noise of the PCF based laser is much higher than that of the shot noise level, which means that the output of the laser is not in the ideal coherent state, and its noise characteristics should be further improved..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 927001 (2013)
Differential Detection System for Measuring the Quantum Noise of Pulsed Light
Guo Xueshi, Gao Kang, Liu Nannan, Yang Lei, and Li Xiaoying
Speed and capacity of the quantum communication system can be increased by using the pulsed continuous variable entanglements with short pulse durations and high repetition rates, because the information can be encoded with individual pulses, and wavelength-division and time-division multiplexing can be applied. To avoSpeed and capacity of the quantum communication system can be increased by using the pulsed continuous variable entanglements with short pulse durations and high repetition rates, because the information can be encoded with individual pulses, and wavelength-division and time-division multiplexing can be applied. To avoid the saturation caused by the repetition rate of light pulses, we experimentally demonstrate a differential detection system, which is suitable for measuring the noise of pulsed lights. The photon-current difference of the two photo-diodes coupled by a transformer is passed through low pass filters to reject the repetition beat signal of pulsed light. Then it is amplified by the cascaded low-noise electronic amplifiers. The common mode reject ratio of the system is about 54 dB, and the noise of the photon-current difference is beyond that of the electronic background up to 8.7 dB when the sum of the total optical power incident to the two photo-diodes is about 0.32 mW. When the pulsed laser serves as the local oscillator, we successfully calibrate the shot noise limit by using balanced homodyne detection, showing that the detection system can be used to measure the quantum noise of pulsed optical fields..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 927002 (2013)
A Portable All-Fiber Source of Quantum-Correlated Photon-Pairs
Li Xiaoying, Zhang Xiuting, Wang Kun, and Cui Liang
An all-fiber source of photon-pairs is experimentally demonstrated. All the components of the source are integrated in a 3U standard case. The repetition rate of pump pulses is about 20 MHz. The wavelengths of both signal and idler photons are in the 1550 nm telecom band, and the bandwidths are about 0.55 nm. The higheAn all-fiber source of photon-pairs is experimentally demonstrated. All the components of the source are integrated in a 3U standard case. The repetition rate of pump pulses is about 20 MHz. The wavelengths of both signal and idler photons are in the 1550 nm telecom band, and the bandwidths are about 0.55 nm. The highest brightness of the photon pairs out of the source is about 4×105 pairs per second. When the brightness of photon pairs is about 104 pairs per second, the ratio between the coincidence and accidental coincidence rates is about 10, which shows there is a strong quantum correlation between the signal and idler photon pairs. Our quantum light source of photon pairs, which is portable and has the advantage of modal purity, can be coupled into the existing fiber network with extremely low loss..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 927003 (2013)
Remote Sensing and Sensors
Thermal Control Design and Proof Test of Altitude Transmissive Optical Sensor
Li Yanwei, Yuan Guoqin, Yang Hongbo, Zhang Hongwen, Liu Weiyi, and Ding Yalin
In order to ensure the optical sensor working in altitude complex environment could gain the high resolution and high quality image, the thermal control design is presented. The design feature and thermal environment are analyzed, and the heat-transfer model is established. The coefficient of heat convection and aerodyIn order to ensure the optical sensor working in altitude complex environment could gain the high resolution and high quality image, the thermal control design is presented. The design feature and thermal environment are analyzed, and the heat-transfer model is established. The coefficient of heat convection and aerodynamic heat are calculated in detail. According to the requirements of thermal control, the method of thermal control design is put forward.The transient thermal analysis is simulated with the IDEAS-TMG software, and the thermal balance tests and the thermal-optical tests are carried out to validate the design. The results of the simulation and tests show that the temperature level of lens component is 20 ℃±1.5 ℃ in 2 h, the axial temperature difference of lens component is no more than 3.1 ℃, the radial temperature difference of lens component is no more than 1.9 ℃, and the variation range of CCD component temperature is 20 ℃～29.4 ℃, satisfying the requirements. The photographic resolution of optical sensor is 51.5 lp/mm, also satisfying the design requirement. The results show that the thermal control design is feasible and reasonable. The method of thermal control design and tests discussed in this paper provides a certain reference to thermal design of other aerial remote sensor..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 928001 (2013)
Research on Integrative Suppression of Internal and External Stray Light in Infrared Optical Remote Sensor
Li Yan, and Liu Jianfeng
The stray light of the infrared sensor consists of external stray radiation and internal stray light. The simulation analysis and suppressions of the stray light of the infrared optical remote sensor are very different from the remote sensors working in visible wavelength. The suppression of the internal and external sThe stray light of the infrared sensor consists of external stray radiation and internal stray light. The simulation analysis and suppressions of the stray light of the infrared optical remote sensor are very different from the remote sensors working in visible wavelength. The suppression of the internal and external stray light are usually contrary. However, the optimizing measures should be applied for the suppression of the external and internal stray light together. The conception of integrative suppression of the external stray light and internal stray light is introduced by studying the changing trend of the internal and external stray light for the same measure in different stes. In an example about the suppression of the stray radiation in an infrared warning camera, the characteristic of the key surface is analyzed and the best measure is adopted by the conception of the integrative suppression. The analysis results can satisfy the requirement of the system..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 928002 (2013)
Spectroscopy
Phytoplankton Chlorophyll Fluorescence Characteristics Excited by Various Light Qualities and Intensities
Liu Jing, Liu Wenqing, Zhao Nanjing, Zhang Yujun, Ma Mingjun, Dai Pangda, Yin Gaofang, Wang Chunlong, Zhang Wei, Duan Jingbo, Yu Xiaoya, Fang Li, and Gan Tingting
Chlorophyll fluorescence emission characteristics of phytoplankton in vivo is closely related to the exciting wavelength and intensity. The fluorescence induct curves under 4 wavelengths of LED (450, 525, 590, 620 nm) and various intensities using chlorella vulgaris and microcystis aeruginosa are tested. Research resulChlorophyll fluorescence emission characteristics of phytoplankton in vivo is closely related to the exciting wavelength and intensity. The fluorescence induct curves under 4 wavelengths of LED (450, 525, 590, 620 nm) and various intensities using chlorella vulgaris and microcystis aeruginosa are tested. Research results show that smooth induct curve are obtained when corresponded exciting light intensity are below 2.8, 4.6, 3.8 4.3 μmol/(m-2·s). Fluorescence intensities of Fo are recorded at the same gain setting, which represent the pigment level. A discrete spectrum can be obtained when considering exciting light photosynthesis active radiation (PAR). Fluorescence affected by wavelength is analyzed combining absorbance data. Significant different chlorophyll fluorescence induct curves are got between phytoplankton in vivo, extracted by 90% ethanol and addition with 0.4 μmol/L 3-(3,4-dichlorophenyl)-1, 1-dimethylurea (DCMU). This work can provide theoretical and data support for phytoplankton photosynthesis activity measurement..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 930001 (2013)
Thin Films
Measurement of the Electro-Optic Coefficients in Electro-Optic Polymer Thin Film Devices with Interdigitated Coplanar Electrodes
Jiang Qiang, Wang Xuan, and Li Zhiyuan
The electric field distribution of modified interdigitated electrodes structure at high fields is analyzed through simulation, and the feasibility that the structure can be used in electro-optic polymer thin film devices is verified. Due to the non-uniform electric field during poling in the thin film devices with inteThe electric field distribution of modified interdigitated electrodes structure at high fields is analyzed through simulation, and the feasibility that the structure can be used in electro-optic polymer thin film devices is verified. Due to the non-uniform electric field during poling in the thin film devices with interdigitated electrodes, the three-dimensional electric field distribution model related with the electrode gap and the polymer thickness is established, and the average electric field is obtained at different poling voltages. For the changes in the structure of the thin film device with the interdigitated electrodes, the transmission-geometry ellipsometric technique based on device with sandwich structure is modified. In addition, the experimental results of electro-optic coefficients of the devices of the interdigitated coplanar electrodes and the sandwich structure are compared under the same electric field. Experimental results show that changes in the structure of thin film device will not cause the resulting electro-optic coefficients changed..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 931001 (2013)
Optical Nonlinear Characteristics of Amorphous InSb Thin Film and Its Super-Resolution Effect
Cai Xiaolin, Wei Jingsong, and Yan Hui
Samples of amorphous-InSb/ZnS-SiO2 structure are deposited on K9 glass substrate with magnetron sputtering method in this study. Optical constants of amorphous InSb thin films are measured by a spectroscopic ellipsometer. The optical band gap is determined to be 0.26 eV by Fourier transform infrared spectroscopy. The nSamples of amorphous-InSb/ZnS-SiO2 structure are deposited on K9 glass substrate with magnetron sputtering method in this study. Optical constants of amorphous InSb thin films are measured by a spectroscopic ellipsometer. The optical band gap is determined to be 0.26 eV by Fourier transform infrared spectroscopy. The nonlinear absorption and nonlinear refraction of the amorphous InSb thin films are measured through well-established Z-scan method at the wavelength of 405 nm. Results show that the amorphous InSb thin films show the characteristics of saturable absorption and self-focusing, the nonlinear absorption coefficient is -3.73×10-2 m/W, and the nonlinear refractive index is 6.64×10-9 m2/W. Based on the nonlinear absorption coefficient, the nonlinear absorption cross section is calculated, which is very close to the reported value of related literature. The thermo-optical effect is investigated by variable temperature ellipsometry method at the wavelength of 405 nm. Analysis indicates that the nonlinear saturable absorption mainly stems from nanosecond laser-induced thermal effect, whereas the self-focusing refraction mainly results from electronic nonlinearity, respectively. The super-resolution effect induced by the saturable absorption characteristic is simulated, and the results show that the nonlinear absorption effect of the amorphous InSb thin films can effectively reduce the size of the transmission spot..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 931002 (2013)
Design and Fabrication of an Irregularly Shaped Distributed Bragg Reflector for Hetero-Junction with Intrinsic Thin Layer Solar Cells
Zhou Jian, Li Hongfei, Liu Yuchen, Tan Huizu, and Liu Zhengxin
An irregularly shaped distributed Bragg reflector (IDBR) for hetero-junction with intrinsic thin layer (HIT) solar cells is designed and fabricated according to the theory of multi-beam interference and the method of iteration. Four types of IDBRs ［S1（500 nm+800 nm）, S2(500 nm+900 nm), S3(500 nm+1000 nm), S4(500 nm+800An irregularly shaped distributed Bragg reflector (IDBR) for hetero-junction with intrinsic thin layer (HIT) solar cells is designed and fabricated according to the theory of multi-beam interference and the method of iteration. Four types of IDBRs ［S1（500 nm+800 nm）, S2(500 nm+900 nm), S3(500 nm+1000 nm), S4(500 nm+800 nm+1000 nm)］ are compared and optimized. The result shows that the structure of S3 with two pairs of α-Si(32 nm)/SiN(61.78 nm) and three pairs of α-SiH(64 nm)/SiN(123.57 nm) is the most suitable structure. With the help of plasma enhanced chemical vapor deposition (PECVD), five pairs of α-SiH/SiN distributed Bragg reflector (DBR) multi-layer films is deposited on the back surface of HIT solar cell. The testing result shows that the reflectivity of S3 is larger than 90% in the wavelength range of 730～1155 nm, and larger than 95% in the wavelength range of 750~1110 nm, which shows the great potential for improving the absorption of light in the wavelength range of 1000~1155 nm (infrared wavelength range), and thus enhance the efficiency of HIT solar cell..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 931003 (2013)
Properties of Ultrafast Speckle Fields in Fresnel Diffraction Region
Song Hongsheng, Liu Guiyuan, Qin Xifeng, Zhang Ningyu, and Cheng Chuanfu
The studies of the speckle field are extended to the area of ultrafast laser, and the concept of ultrafast speckles is introduced. In the theoretical research, the ultrafast speckle fields in the Fresnel diffraction region and the general expressions of their autocorrelation functions are discussed, and then the specklThe studies of the speckle field are extended to the area of ultrafast laser, and the concept of ultrafast speckles is introduced. In the theoretical research, the ultrafast speckle fields in the Fresnel diffraction region and the general expressions of their autocorrelation functions are discussed, and then the speckle intensity autocorrelation function is solved using the optical field autocorrelation and the intensity ensemble average. As time delays, ultrafast speckle intensity space autocorrelation curves present a characteristic of periodic oscillation and the frequency gradually increases. Combined with the computer simulation, the formation and the never-before understood dynamic behaviors of the ultrafast speckles in the Fresnel diffraction region are found and explained. Such dynamic behaviors include the increased speckle grains, the structures of the interference fringes in the speckle grains and the decrease of the spatial period, and the interference fringes gradually disappearing from two sides to the center of the observation plane, etc..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 932001 (2013)
Vision, Color, and Visual Optics
Colorimetric Characterization of a Digital Camera under General Office Lighting Environments
Mi Chaobo, Huang Xiaoqiao, and Shi Junsheng
The colorimetric characterization of digital color devices is the basis of image copy and color management process. Aiming to provide convenience for general users to characterize camera, based on studies of the characterization using instruments to measure samples under two office environments of daylight lighting durThe colorimetric characterization of digital color devices is the basis of image copy and color management process. Aiming to provide convenience for general users to characterize camera, based on studies of the characterization using instruments to measure samples under two office environments of daylight lighting during the day and fluorescent lighting at night, a characterization scheme that a user does not use professional instruments under daylight lighting is presented, but on one condition that the user has ColorChecker standards 24 color card. The characterization accuracy is studied, and experimental results show that, using professional instruments to measure samples, the characterization accuracy is 3.5~3.9 CMC (11) color difference units under environments of fluorescent (lighting and daylight lighting); not using instruments, the characterization accuracy is 3.75 CMC (11) color difference units under the environment of daylight lighting, and the difference of characterization accuracy is very small between using and not using instruments; not using instruments, the characterization accuracy varies in 0.5 CMC (11) color units at the condition of daylight changes in illumination and color temperature during sunny day from 1200 to 1500..
Acta Optica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 9, 933001 (2013)
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