Acta Optica Sinica
Co-Editors-in-Chief
Qihuang Gong
Sun Xuejin, Li Hao, and Tang Liping

A few observation samples of atmosphere particles are collected. Based on Mie scattering theory, atmosphere volume scattering polarization degree is simulated and analyzed in visible and infrared band by solving the Mueller matrix. The results show that atmosphere volume scattering polarization is positive as a whole. The polarization of incident light does not change in forward scattering angles, but it is slightly negative in backward scattering angles. Atmosphere linear polarization degree varies smoothly with scattering angle, and gradually approaches to Rayleigh scattering when scattering scale parameter decreases. Scattering scale parameter and particle complex refractive index are determining factors of atmosphere linear polarization degree. In the visible light and near-infrared band, the linear polarization degree of fog changes less with wavelength, and varies with scattering angle as multi-peaks distribution. The linear polarization degree of fog reaches maximum at scattering angles of 120°,140° and 180°. In the infrared band, the linear polarization degree of aerosol changes less with wavelength, and varies with scattering angle as single-peak distribution. The linear polarization degree of aerosol reaches maximum at scattering angles between 80° and 140°.

Jan. 01, 1900
  • Vol. 31 Issue 5 501001 (2011)
  • Wei Xiaodong, and Zhang Hua

    The optical properties of nonspherical dust aerosols in the wavelength range of 0.2~40 μm are calculated by combination of T-matrix method and an improved geometric optics under the conditions of representative shape distribution and size distribution. By comparing the optical properties of dust particles between nonspherical and isochoric sphere hypothesis. It is found that 1) the shape of dust aerosols has a smaller influence on the extinction efficiencical factor, scattering albedo and asymmetry factor compared to the size distribution; 2) the difference of phase function between nonspherical and spherical dust aerosols in the short-wave region is significant, especially in the visible region, and they change with different scattering angles; 3) in short-wave region, the extinction-to-backscattering ratio in the so-called lidar equation is affected by the shape of dust aerosols greatly, therefore, the nonspherical effects should be considered in the retrieval of dust optical thickness by using the lidar equation.

    Jan. 01, 1900
  • Vol. 31 Issue 5 501002 (2011)
  • Huang Changchun, Li Yunmei, Sun Deyong, Le Chengfeng, and Jin Xin

    Scattering coefficient bp, backscattering coefficient bbp and concentration of particles are obtained from Taihu lake waters during three campaigns in Oct. 2006, Mar. 2007 and Nor. 2007. Specific scattering and backscattering coefficient of total suspended particle (TSPM), inorganic suspended partide (ISPM) and organic suspend particle matter (OSPM), and spectral power exponents slope are calculated from sampling data. Then the spectral characteristic and formative mechanism of bp and bbp are explored further. The result indicates that the average value of specific scattering coefficients of TSPM, ISPM and OSPM are 0.634 (550 nm), 1.057 (532 nm) and 0.396 (532 nm) gm-2, respectively. The average value of specific backscattering coefficients of ISPM and OSPM is 0.0051(532 nm) and 0.0022 (532 nm) gm-2. The average backscattering ratio(B) in Oct. 2006, Mar. 2007 and Nov. 2007 is 0.01078, 0.01375 and 0.01251, respectively. bbp, bp and B have strong wavelength dependence. However, strong absorption effects of OSPM and CDOM at short wavelength and chlorophyll at 675 nm make the wavelength dependence weak. Spectral exponent has strong relation with ISPM/OSPM, bbp(532 nm), but week relation with the particle size distribution slope.

    Jan. 01, 1900
  • Vol. 31 Issue 5 501003 (2011)
  • Liang Lingliang, Yan Xiaona, Han Feng, Cao Lan, Dai Ye, and Yang Xihua

    Based on Kogelnik′s coupled-wave theory, we derive the coupled-wave equations of a volume holographic grating (VHG) illuminated by ultra-short pulsed laser, and obtain its diffraction electric field and instantaneous diffraction intensity. It is found instantaneous diffraction intensity of volume grating is affected by the VHG′s structural parameters, such as the grating spacing, grating thickness, and the refractive-index modulation of the VHG. By changing these parameters, diffracted characteristics could be controlled and this may be used in the pulse shaping. In simulation, we also find group time delay of the diffracted beam with respect to the readout pulse in the negative time axis and this time delay are affected by the grating spacing and thickness. With the concept of group velocity, we give a quantitative analysis about this time delay.

    Jan. 01, 1900
  • Vol. 31 Issue 5 505001 (2011)
  • Wang Zhenhua, Wu Yonggang, Ling Leijie, Xia Zihuan, Chen Naibo, and Liu Renchen

    A new tunable orthogonal grating consisting of two weakly modulated subwavelength gratings perpendicularly to each other is presented. Using the rigorous coupled-wave analysis (RCWA), the spectra are calculated and the characteristics of guided-mode resonance for transverse electric (TE) and transverse magnetic (TM) polarized light is analyzed. It is demonstrated that a wide-range tunability of such structure is obtained via varying the spacing between the gratings (the distance between the two resonant wavelengths is continuously tunable from 0 to 62.7 nm). For the normally incident waves of both TE and TM polarized light, the structure turns out to have the same spectrum and resonance peaks, and it is the same as the overlay result of parallel double grating. For the obliquely incidence of TE/TM polarized light, the separation of the resonant peaks appears. At the same time, some specific wavelengths are maintained with the increase of the incident angle, such as the resonance peaks of 582.3 nm and 590.8 nm for incident plane P1, and those of 590.8 nm and 612.4 nm for P2.

    Jan. 01, 1900
  • Vol. 31 Issue 5 505002 (2011)
  • Wang Ju, Yu Jinlong, Luo Jun, Wang Wenrui, Wu Bo, Han Bingchen, Guo Jingzhong, and Yang Enze

    A novel all-optical serial to parallel converter is proposed. The scheme mainly consists of time-and-wavelength-interleaved pulse train generation and the sequential multi-wavelength conversion based on the cross-phase modulation (XPM) of a single semiconductor optical amplifier (SOA). Using super-continuous spectrum generation in high nonlinear fiber, a time-and-wavelength-interleaved pulse source is generated with tunablity of both channel wavelength and bit rate. And the all-optical serial to parallel conversion has been implemented based on sequential multi-wavelength conversion in SOA. In the experiment, 40 Gb/s serial optical signals are converted into 8-channel 5 Gb/s parallel optical signals. It should be pointed out that, this technique can achieve the all optical serial-to-parallel conversion of more than 100 channels without remarkably increasing the insertion losses, which will be a solid preparation for optical label processing and random access memory (RAM) technique in packet switching networks.

    Jan. 01, 1900
  • Vol. 31 Issue 5 506001 (2011)
  • Wang Xin, Chen Lin, and Cao Zizheng

    In order to explore the influence of the modulation depth in subcarrier OFDM optical transmission system, the bit error ratio response of subcarrier OFDM optical systems in intensity modulator (IM) is investigated by simulation and experiment when the modulation depth is changing. Simulation and experimental results show that there is an optimum carrier sideband ratio (CSR), which is about 20, when subcarrier OFDM signal transports through optical fiber. Too large or too small CSR will cause the system′s bit error ratio performance decrease. It is shown that the PM system has a good transmission characteristics when the sidebands is suitable and constant with the modulation depth.

    Jan. 01, 1900
  • Vol. 31 Issue 5 506002 (2011)
  • Yu Kuanglu, Wu Chongqing, Guo Xuan, Wang Zhi, Shi Meirong, and Wu Wenbin

    The Beer-Lambert law, taking into account the pressure broadening of the absorption lines function is analyzed, then it is used for multi-point acetylene gas detection. A fiber optical multi-point acetylene sensing system using dense wavelength division multiplexers, which takes advantage of different absorption lines to tag different probes in the system, is put forward. This system is easy to build and operate, while it does not need to modulate the light source. In addition, the system has a much smaller system loss and cross talks as the consequences of employing the dense wavelength division multiplexers. Theoretical results show that the maximum sensor number of the system is eighteen with a 0.5% sensitivity using the absorption lines from 1510 to 1540 nm. A three-point sensing system is experimentally demonstrated and the errors of the measured results are within 1.8%.

    Jan. 01, 1900
  • Vol. 31 Issue 5 506003 (2011)
  • Hou Shanglin, Zhang Shujun, Li Suoping, Liu Yanjun, and Xu Yongzhao

    The characteristic equation of a doubly cladding fiber with an inner cladding made of negative refractive index material is presented by full vectorial mode method. Its mode distribution, dispersion and time delay are demonstrated. The results indicate that this kind of fiber has some abnormal properties, such as the single mode existing in certain normal frequency. Along with increasing diameter of inner cladding, different propagation constants exist in the same mode and normalized frequency. The diameter of inner cladding has great influence on the dispersion and group time delay. The dispersion can reach -158000 ps/(nm·km) and group time delay can become very large by increasing the diameter of the inner cladding. These results provide theoretical basis for designing novel dispersion compensating fiber and photonic devices.

    Jan. 01, 1900
  • Vol. 31 Issue 5 506004 (2011)
  • Li Jialei, Xu Hualong, and He Jing

    The wavelet network and its improvement version are applied to the temperature compensation of start-up drift of fiber optic gyro (FOG). Based on experiments in the entire temperature range of FOG, influences of inner temperature, temperature gradient and temperature variation rate on start-up drift are analyzed, and the start-up drift model consisting of the above three temperature factors is built. Then compensation based on the model can be carried out to improve the start-up accuracy of FOG. The experimental results indicate that the start-up drift of FOG can be compensated effectively by using wavelet network, and the problem of real-time applications can be settled.

    Jan. 01, 1900
  • Vol. 31 Issue 5 506005 (2011)
  • Yang Meixia, Zhong Ming, Ren Gang, He Hengxiang, Liu Wenbing, Xia Huijun, and Xue Liangping

    A method is proposed to calculate the focusing characteristics of short-wavelength laser beam through short-focus system. The problem of random phase jumps, wave function distortion and insufficient sampling rate will be met when the optical field distribution of a focused laser beam is calculated by fast Fourier transform method and short-wavelength laser beam passes through the short-focus system. By using coordinate transformation in the fast Fourier transform calculation, the limitation of the same input screen special scale, the same diffraction screen sptial scale and the same sampling grid spacing is broken. The optical-field distribution of a focused laser beam can be calculated in detail. At the same time, two-step calculation is used to avoid the conflict between the coordinate space of the geometric expansion and the diffraction limit when the light field near the focus is calculated.

    Jan. 01, 1900
  • Vol. 31 Issue 5 507001 (2011)
  • Li Hongyan, Ma Zhijian, Zhong Liyun, and Lü Xiaoxu

    The mathematical expressions of synthetic aperture digital holography and phase-shifting synthetic aperture digital holography are presented. Based on the cross-correlation algorithm of both the object waves and the phase-shifting sub-holograms, a high precision synthetic method of the sub-holograms in phase-shifting synthetic aperture digital holography is proposed. Firstly, the position relation of the sub-holograms is determined by the cross-correlation algorithm of the adjacent object waves, then phase-shifting synchronization matching is implemented by the cross-correlation algorithm of the phase-shifting sub-holograms, thus it is convenient to reach the separation of the spatial connection matching of the sub-holograms and phase-shifting synchronization matching of the phase-shifting holograms. By use of the Chinese standard resolution test chart 2# as the experimental sample, the results show that the correlation coefficient of both the sub-holograms connection matching and phase-shifting synchronization are more than 0.99, and the reconstructed image with high quality is obtained.

    Jan. 01, 1900
  • Vol. 31 Issue 5 509001 (2011)
  • Ma Wenjuan, Gao Feng, Zhang Wei, Yi Xi, Li Jiao, and Wu Linhui

    The third-order simplified spherical harmonics approximation to radiative transfer equation is utilized as forward model for the fluorescence diffuse optical tomography (FDOT). This algorithm overcomes the drawback of big computation consumption of PN approximation and limitation that DA is unapplicable to the low-scattering tissue. The time-domain technique offers the potential advantages in directly measuring lifetime and has the best performances of simultaneously recovering of fluorescent yield and lifetime distributions, as well as resolving multiple components. On these bases, an image reconstruction method of generalized pulse spectrum technique based on the SP3 equation(SP3-GPST) is presented, and it is an extent of generalized pulse spectrum technique based on the diffusion equation(DA-GPST). Simulation results show that SP3-GPST performs better than DA-GPST.

    Jan. 01, 1900
  • Vol. 31 Issue 5 510001 (2011)
  • Wu Yiquan, Ji Shouxin, and Zhan Bichao

    Aiming at the detection problem for dim target in infrared image that contains background interference and noise, a detection method for dim target is proposed based on nonsubsampled contourlet transform (NSCT) and independent component analysis (ICA). Firstly, the background image separated from the original image by fast independent component analysis is subtracted from the original image. The residual image is denoised based on nonsubsampled contourlet transform and the new Top-hat transform is used as a filter, thus the preprocessed image is obtained. Then, the preprocessed image is segmented by the threshold selection algorithm based on the within-class variance and area difference between background and target. Lots of experiments are done with infrared images including small targets and a comparison is made with the detection methods of infrared target based on fast independent component analysis and nonsubsampled contourlet transform. The experimental results show that the suggested method is stronger in anti-noise performance and more superior in detection performance.

    Jan. 01, 1900
  • Vol. 31 Issue 5 510002 (2011)
  • Hou Zhiling, Su Xianyu, and Zhang Qican

    After studying the composite phase-shifting algorithm for 3D shape compression, two novel methods two-channel phase encoding algorithm and three-channel phase encoding algorithm are proposed. They can improve the compress ratio and the reconstruction quality by storing the 3D shape data into two or three channels of a 24 bit color image. Computer experiments and quantitative analysis provide a guide to achieve appropriate reconstruction quality and compression ratio.

    Jan. 01, 1900
  • Vol. 31 Issue 5 510003 (2011)
  • Lin Liangkui, Xu Hui, Xu Dan, and An Wei

    The closely spaced objects (CSO) create blur pixel cluster on the infrared focal plane; therefore, in order to effectively track and identify each object of CSO, it is necessary for the sensor signal processing to resolve them. A novel method of CSO infrared resolution based on reversible jump Markov chain Monte-Carlo (RJMCMC) method is presented. The method firstly creates an infrared focal plane image model, then constructs a framework of Bayesian inference for CSO resolution, and subsequently uses the RJMCMC to perform computation of the parameters′ posterior distribution, ultimately the joint estimation of objects number is obtained, positions and intensities. Simulation with infrared sensor viewing midcourse CSO are carried out to test the performance of the method, and the results confirm the effectiveness of the method.

    Jan. 01, 1900
  • Vol. 31 Issue 5 510004 (2011)
  • Xu Xianwen, Hong Guanglie, Ling Yuan, Hu Yihua, and Shu Rong

    In order to detect the phase error caused by platform vibration of synthetic aperture lidar, a new method of vibration measurement was proposed, which extracted the detection signal phase directly with heterodyne balanced detection and quadrature signal processing technology. Then the errors caused by the unbalance between the two quadrature signals were corrected and the obtained phase sensitivity was 1.45 rad. The experiment showed that this method not only can accurately measure phase variation caused by small vibration with low frequency, but also was insensitive to the amplitude of echo signals′ fluctuation, which was different from the laser Doppler vibrometer.

    Jan. 01, 1900
  • Vol. 31 Issue 5 512001 (2011)
  • Zheng Xiangming, Li Zhulian, Fu Honglin, He Shaohui, Li Rongwang, Li Yuqiang, Zhai Dongsheng, and Xiong Yaoheng

    Kilo-Hertz (kHz) laser ranging is one of effective methods to increase the measurement frequency and improve the accuracy of normal point (NP). Principle and method of realizing common optical path kHz laser ranging are analyzed, which include optical path, circuit and computer control etc. Novel concept of rotation shutter is proposed to build kHz system, and control system of 1.2 m telescope common optical path kHz laser ranging has been developed. It has been successfully used for routine observation. Actual observations show that the system performs well and runs stable. The ground target ranging accuracy is about 5 mm, and satellite ranging accuracy is better than 2.0 cm.

    Jan. 01, 1900
  • Vol. 31 Issue 5 512002 (2011)
  • Zheng Dongliang, and Da Feipeng

    The gamma distortion in fringe projection profilometry system will create obvious measurement error. A gamma correction method based on the pre-coding of projected grating is proposed to reduce the measurement error caused by the gamma distortion. By applying an appropriate pre-coding value to the projected grating, the gamma distortion effect is attenuated and the accuracy is enhanced. Experiments are carried out to verify the proposed method. The traditional phase shifting profilometry is combined with the gamma correction method. Projected sinusoidal grating of the phase shifting profilometry are modulated by the appropriate pre-coding value. Then, accuracy of measurement of the phase shifting profilometry can be effectively enhanced. Compared with the existing pre-coding gamma correction method, the proposed method is simple and effective.

    Jan. 01, 1900
  • Vol. 31 Issue 5 512003 (2011)
  • Xu Jiancheng, Du Yawei, Xu Qiao, Peng Baojin, and Wu Genzhu

    The process accuracy of phase-masked spatial carrier interferogram is related to the performance of the dynamic interferometer. According to the property of the phase mask, a method based on Fourier transform is proposed to extract the phase from the phase-masked spatial carrier interferogram. The method translates the full-resolution interferogram into a linear spatial carrier interferogram by pixel rearrangement, and then extracts the final full-resolution phase distribution by Fourier transform and pixel rearrangement again. Experimental results show that the peak-valley value and the root mean square of four-step phase shifting algorithm are 0.7467λ and 0.0348λ respectively, while those of the proposed method are 0.2989λ and 0.0088λ. Thus the proposed method is more accurate than four-step phase shifting algorithm for analyzing phase-masked spatial carrier interferogram.

    Jan. 01, 1900
  • Vol. 31 Issue 5 512004 (2011)
  • Chen Fang, Liu Ruipeng, and Qi Zhimei

    LiNbO3-based integrated optical waveguide Mach-Zehnder interferometer (MZI) with push-pull electrodes and evanescent field sensing window is developed. By using standard micro-opto-electro-mechanical-system (MOEMS) technique and titanium-indiffusion method, LiNbO3 monomode channel waveguide MZI array with modulating electrodes is fabricated. The near-field profile of the guided mode is detected after launching light into the LiNbO3 waveguide by fiber end-fire coupling. The phase-modulating property of the LiNbO3 MZI is investigated. The experimental results show that the phase modulation of the MZI is fully reversible and its half-wave voltage Vπ is 5.61 V, and fringe contrast is 0.62. The phase-modulating capability allows the initial phase of the MZI device to be a quadrature point to make the device work in the linear-response region for biochemical sensor.

    Jan. 01, 1900
  • Vol. 31 Issue 5 513001 (2011)
  • Xiao Chongli, Wan Chunming, Dong Yuan, Liu Xudong, and Song Yeying

    A new scheme which can generate special intensity distribution hollow laser beams-double half-Gaussian hollow beams by modified Cassegrain optical system is presented, and the optical system is composed of reflecting positive conic mirror and spheric reflector. The factors such as conic angle of positive conic mirror, the divergence angle of Gaussian beams and the ature radius of spherical reflector, which influence on the ratio of ring width to radius and spherical aberration, are analyzed in detail. By adjusting the above parameters, the double half-Gaussian hollow beams with the ratio of ring width to radius being 0.1~1 can be easily obtained. And the experimental results show that the hollow beams which are generated by the modified Cassegrain optical system is double half-Gaussian hollow beams. The research provides the theory of generating the double half-Gaussian hollow beams with the ratio of ring width to radius being 0.1~1 and establishes solid foundation in the fields of scanning image and communication.

    Jan. 01, 1900
  • Vol. 31 Issue 5 514001 (2011)
  • Tian Yuzhen, Zhao Shuai, and Guo Jin

    In order to analyze the faraway non-cooperative target, the research of faraway non-cooperative target ranging experiment is proceeded by using multi-pixel photon counter (MPPC) where photon counting laser ranging method and pulse ranging method is combined. Weak signal reflected by faraway non-cooperative target MPPC is simulated in the laboratory. By analyzing the return photons which are detected by MPPC, the distribution of photons reflected from the target is studied. The interval of start and stop pulses is calculated with different algorithms, and the influence of these algorithms on the ranging result is analyzed. 7220 pulses have been obtained by MPPC, 4 GHz sample rate oscillograph and pulsed laser with 5 ns pulse width. The statistic results prove that the return signals obey Poisson distribution. The optimal ranging result has been obtained by constant fraction discrimination method: the deviation of ranging result and measured distance is 2.8 cm, the weighted standard deviation is 0.9 cm, and the ranging result deviation obtained by constant amplitude method and autocorrelation method are both over 40 cm. The reasons why different methods do not produce the same results are given by comparing the constant fraction discrimination method with other algorithms.

    Jan. 01, 1900
  • Vol. 31 Issue 5 514002 (2011)
  • Zhao Weifang, Hou Wei, Guo Lin, Lin Xuechun, and Li Jinmin

    A Nd:GdVO4 crystal is end-pumped by a fiber-coupled laser diode (FCLD), and high power of single-frequency laser output is achieved. The four-mirror bow-tie ring cavity with a Faraday rotator and a half wave plate is applied to eliminate the spatial hole-burning effect. A solid etalon is inserted into the cavity to obtain single-frequency 1063 nm output of the narrow line width. The maximum output is 7.57 W and the optical-optical conversion efficiency is 41.8% with 18.10 W of the incident power.

    Jan. 01, 1900
  • Vol. 31 Issue 5 514003 (2011)
  • Zhang Pingping, Ma Yan, and Li Tongbao

    Particle optics model for one-dimentional atom lithography is optimized with Monte-Carlo method. The initial condition of each trajectory is stochastically selected . The effects of isotope, longitudinal velocity distribution and transverse Gaussian divergence are systematically evaluated. Optimized model is compared with original model and the surface growth effect is described qualitatively. Excellent agreement is seen between numerical simulation and experiment under different laser powers. Furthermore, the effect of detuning is also discussed. It is found that good result can be obtained when the detuning is 250×2π MHz. The model presented takes all the factors into consideration and it provides better theoretical guide for current experiment.

    Jan. 01, 1900
  • Vol. 31 Issue 5 514004 (2011)
  • He Xiaoming, Chen Danping, Yu Bingkun, Ren Guohao, and Yan Xiaona

    Ce3+-doped scintillating glasses with up to 30%(mole fraction) Gd2O3 and high density in the system SiO2-B2O3-Al2O3-Gd2O3 have been prepared. Absorption and fluorescence properties of substitutions of Al2O3 by BaO and La2O3 have been investigated. Optimum luminescent intensity and absorption in these glasses is detected when the mole fraction of BaO is 10%. Meanwhile, substitutions of Al2O3 by BaO or La2O3 also lead to the red shift of the emission and excitation peak. Scintillating performance are shown under X-ray irradiation, but the result shows that the peak wavelength red shifts 40 nm compared with the peak of emission spectra under 330 nm ultraviolet light excitation suggests the different mechanism between fluorescence and scintillating light.

    Jan. 01, 1900
  • Vol. 31 Issue 5 516001 (2011)
  • Wang Mahua, Zhu Hanqing, and Zhu Guangping

    A bionic network nanostructure of zinc oxide (ZnO) similar to Morpho butterfly wing, was fabricated by a vapor transport method. Its morphology was characterized by X-ray diffraction, scanning electronic microscope and its backward scattering characteristics was investigated. The backward scattering patterns of the sample, giving the exhibition of wavelength-selected and angle-dependent characteristics, similar to the optical effect of morpho butterfly wing, were observed. The mechanism of this optical function was discussed based on finite difference time-domain and rigorous coupled-wave analysis method. The result showed that the sample′s periodic surface results in the optical effect.

    Jan. 01, 1900
  • Vol. 31 Issue 5 516002 (2011)
  • Xiao Yi, Chen Zhe, Yu Jianhui, and Tang Jieyuan

    The propagation of a (1+1)D spatial optical soliton beam at an oblique angle of incidence to a nonlocal nonlinear interface is studied by using numerical method. It is found that the intensity dependence of the propagation of a light beam at a nonlinear nonlocal interface can be portrayed by 5 node points of beam width of the incident soliton beam, which mark respectively 5 critical intensity value of the incident beam that cause the sudden changes of the propagation of the reflection or the transmission beam. It is also found that with the incident beam width keep unchanged and its power is increased, the 5 sudden change points of the propagation of the incident optical breathing beam can also arise, which illustrate that the power dependence is essentially intensity dependence. The change of the values of the 5 node points of beam width of the incident soliton beam with the change of nonlocality degree is also studied.

    Jan. 01, 1900
  • Vol. 31 Issue 5 519001 (2011)
  • Liu Yanli, Luo Aiping, Luo Zhichao, and Xu Wencheng

    Based on the fiber link consisting of a section of a positive-dispersion and a negative-dispersion optical fiber, a method of pulse compression is proposed. The parabolic self-similar pulses are generated through a normal-dispersion fiber, then compressed by an anomalous dispersion fiber. The effect of initial chirp on pulse shaping is numerically investigated with the symmetrical distribution Fourier method. By introducing a dimensionless factor to characterize the pulse shape, it is found that, the initial negative chirp accelerates pulse shaping and the initial positive chirp is apt to broaden the range of best linear chirp of the best parabolic pulse. And the effect of third-order dispersion on pulses compression is theoretically and numerically investigated. The results show that the third-order dispersion can be weakened by using third-order dispersion partial compensation fiber.

    Jan. 01, 1900
  • Vol. 31 Issue 5 519002 (2011)
  • Gao Shenyan, and Guo Qizhi

    The chaotic and hyper-chaotic synchronization of non-degenerate optical parametric oscillators are investigated. The chaotic and hyper-chaotic synchronization of two non-degenerate optical parametric oscillators are realized by using unidirectional coupling driving method. When driving system is in chaotic and hyper-chaotic state respectively, it is got the range of the coupling constant to achieve chaotic synchronization in different states by using the chart of maximum condition Lyapunov exponent spectrum. Besides, by using idle-wave, signal-wave and two-mode coupling different results are got. It is got that signal-wave coupling is better than idle coupling, and two-mode coupling can optimize the chaotic synchronization. The synchronization results are perfectly verified by phase diagram and time series charts of the systems.

    Jan. 01, 1900
  • Vol. 31 Issue 5 519003 (2011)
  • Tang Yunhai, Wu Quanying, Qian Lin, and Liu Lin

    The principle of mean curvature flow is illustrated. An optimizing method using mean curvature flow is proposed which can reduce the undesirable astigmatism in some regions of the progressive addition lens surface while retaining desirable optical features of the progressive lenses. It is presented that the more the surface of the progressive lens becomes closer to spherical by the process of mean curvature flow, the more the astigmatism is smaller. The optimizing algorithm and an example are given out. An initial designed progressive addition lens and an optimized lens by this method are manufactured and tested. Compared with the original lens, the optimized lens has smaller maximum astigmatism value and larger clear region on the intermediate zone and the distance-vision zone.

    Jan. 01, 1900
  • Vol. 31 Issue 5 522001 (2011)
  • Jiao Chunye, Wang Feng, Jiang Xiaohua, Liu Shenye, Yang Zhenghua, Li Sanwei, Li Zhichao, Liu Yonggang, Chen Ming, Zhang Xiaoding, Gu Yuqiu, and Ding Yongkun

    Full aperture backscattering diagnosis system of Shenguang Ⅲ laser prototype facility is optimized under the condition of complex laser optical mirrors. Nonlinear scattering signals are collected by long focus Fresnel lens and focalize at the focus as background light is filtrated by vacuum spatial filter. Nonlinear scattering signals have been separated in space from background light. Then coaxial problem of nonlinear scattering signals with background light is resolved. Scattering light energy and spectrum of full aperture backscattering is measured in hohlraum experimental on Shenguang Ⅲ laser facility. Full aperture backscattering diagnosis system after optimization is validated by the hohlraum experiment, which offers possible condition and important referrence for exact laser-target coupling and energy balance precision diagnosis.

    Jan. 01, 1900
  • Vol. 31 Issue 5 522002 (2011)
  • Wang Feng, Wu Weidong, Jiang Xiaodong, and Tang Yongjian

    After top layer of 2.5 μm being removed, surface of optical component becomes smooth and flat, and rms roughness is less than 1.45 nm in the range of 0.9 mm×1.2 mm. Content of impurity element (Fe, Ce ect.) is reduced and the size of sub-surface defect is decreased. Periodic polycrystal structure appears at surface of fused silica after being modificated resulting in the increment of transmittance from 400 to 1100 nm, damage is restrained and damage threshold raises. With increasing of modification depth, damage probability of optical component reduces further. Results indicate that reactive plasma modification will be a hopeful method for rapid and nondestructive processing of large surface fused silica optical component.

    Jan. 01, 1900
  • Vol. 31 Issue 5 522003 (2011)
  • Zhu Xianchang, Cao Xuedong, Wu Shibin, and Zhang Peng

    A new method of microlens focal length measurement by rotation method based on grating diffraction is introduced. When parallel rays travel through the grating, various angle-order diffracted rays will appear behind the grating because of grating diffraction. According to the grating equation, the angle between the ±1 st-order and the 0-order diffracted rays is determined by grating period and testing wavelength. Taking a camera nearby the focus of microlens to get the picture one by one, from clarity function of the picture, the focus position will be decided. In addition, the distance of the +1 st-order and the 0-order spot center can be tested from the picture. With the angle and spot central distance between the ±1 st-order and the 0-order, the focal length can be measured. The measurement result shows that this method has a good precision for focal length measurement of microlens. And because of its high efficiency, this method can also be used for focal length of microlens array measurement.

    Jan. 01, 1900
  • Vol. 31 Issue 5 523001 (2011)
  • Wang Mu, Zhao Ruitu, Lin Hai, and Zhao Xin

    To achieve high-gain S-band waveguide amplifiers with integrated configuration, S-, U-, and F-bend waveguides based on Tm3+-doped germanate glasses have been designed in an 8 cm×6 cm substrate. Using simulated-bend method, the optimal radius for the curved structure is offered to be 1.90 cm with loss coefficient of 0.04 dB/cm. For the F-bend waveguide, the internal gain at 1482 nm is derived to be 13.01 dB, which is higher than the values of 8.21 and 4.22 dB in the U-and S-bend waveguides, respectively, and nearly three times higher than that of the straight one (3.84 dB). Simulation results indicate that the reasonable optical path design can considerably enhance the optical gain in Tm3+-doped germanate glass channel waveguides.

    Jan. 01, 1900
  • Vol. 31 Issue 5 523002 (2011)
  • Fu Kangyin, and Chen Yuegang

    Due to different phase delay of light wave propagating through waveguides with different length, wave front can be modulated by waveguide array. Based on theoretical derivation, the focused wave can be obtained through triangular waveguide array. Using the finite-difference in time-domain method, the focusing in the convex triangular waveguide arrays is simulated, and the results agree with theoretical derivation well. Simulation results also indicate that the concave triangular waveguide array can split the beam.

    Jan. 01, 1900
  • Vol. 31 Issue 5 523003 (2011)
  • Yin Luqiao, Yang Weiqiao, Li Shuzhi, Cheng Bei, and Zhang Jianhua

    More and more attentions have been focused on the lighting source as it plays an important role to people′s health. The light emitting efficiency of light emitting diode has been broken through year by year and now it has been surpassed that of the traditional lighting source. In order to improve the lighting quality by a lighting source with flexible color temperature, a data base is created with different color temperature by mixing different proportion luminous flux of red, green and blue light emitting diode based on theoretical calculations. The data base is embedded into the control program and it can run different proportion to realize light source variation with color temperature at different time. The experimental results show that the lighting source can realize correlated color temperature from 2300~7000 K, real color temperature is in accordance with that of theoretical calculation. Thus a sunlight-style lighting device is realized fundamentally.

    Jan. 01, 1900
  • Vol. 31 Issue 5 523004 (2011)
  • Yu Qing, Yu Xiaofen, Liu Wenwen, and Cheng Lingli

    Compared with other beam splitting devices, digital micromirror device (DMD) can control the deflection state of every micromirror, which can construct the flexible array light source with tunable size of point light source and distance. Based on the previous researches, the theoretical model of DMD is deduced and the optical path of measurement is improved. Combined with actual usage, the suitable parameters of array light source are found. The relation between longitudinal resolution of parallel confocal microscope and the size of point light source is gotten. Finally, the parallel confocal measurement system based on DMD is proved by experiments.

    Jan. 01, 1900
  • Vol. 31 Issue 5 523005 (2011)
  • Lü Hongjun, and Xie Guangjun

    Under the non-measuring circuits, it is used the truth table method to propose the concept of two quantum error-correcting circuits and then a circuit which can code and correct one-qubit error、two-qubits error is construeted. This quantum circuit can correct one-qubit error and two-qubits error at the same time, break through the former limit that the circuit can only correct one-qubit error. A coding circuit is recommended to encod auxiliary bits of inputing information and judge the different input-bits quantum states according to different auxiliaries. During the process of designing 7-qubits error correction circuit, a modular thinking is advanced based on the 5-qubits error-correction circuits which can simplify the multi-qubits error-correction circuit design process.

    Jan. 01, 1900
  • Vol. 31 Issue 5 527001 (2011)
  • Li Yueke, Zhang Guiming, and Gao Yunfeng

    The atomic emission and cavity field spectrum of an atom interacting with two-mode fields in the pair-coherent states are investigated. The results for weak initial fields are presented. The spectral structure is discussed. It is found that the peak position of the atomic emission spectrum and the height of the cavity-field spectrum are both affected by the average photon number and the photon-number difference between the two modes sensitively. The effect of the two field intensity on the peak position of the cavity field spectrum and the height of the atomic emission spectrum are both not obvious. Fixing the photon difference of the two fields, the Rabi splitting will arise in atomic emission spectra with strong initial fields. This is useful in experiment for measurement of the Rabi frequency and the atom-field coupling constant. The cavity-field spectrum structure can be modulated by the photon-number difference of the two fields.

    Jan. 01, 1900
  • Vol. 31 Issue 5 527002 (2011)
  • Zhang Xiubao, Yuan Yan, and Wang Qian

    A new method for spectral discrimination—spectral information divergence of spectral gradient [SID(SG)] is proposed. Firstly, the spectral gradients are estimated for discriminating the spectral local detailed characteristics, and then the information divergence of the spectral gradient is estimated for comparing their whole shape. The simulated spectra and the real measured are used as experimental data, the discrimination ability of the SID(SG) is compared to that of other methods, and relative spectral discriminatory entropy (RSDE) is used as standard to evaluate the experimental results quantitatively. RSDE values of the SID(SG) are 1.2849 and 1.5184, respectively, smaller than that of the several discrimination methods in each array. This indicates the superiority of SID(SG) over several other discrimination methods.

    Jan. 01, 1900
  • Vol. 31 Issue 5 530001 (2011)
  • Lai Bo, Lian Yu, Pang Cuicui, Zhou Yuexi, Qin Hongke, Zhou Jihong, and Zhang Sheng

    In order to study fluorescence characteristics of typic azo and non-azo dyes, fluorescence characteristics of acid orange Ⅱ, indigo carmine and acid orange Ⅱ without azo-bone are detected by excitation-emission matrix (EEM) fluorescence spectra. Results show that fluorescence intensity of typic azo dyes (such as acid orange Ⅱ) is very weak, while fluorescence intensity of typic non-azo dyes (such as indigo carmine) is very strong. In other words, azo dyes in wastewater can be distinguished quickly by EEM spectral technique. It is clear that azo-bone of azo dyes has fluorescen quenching, which results in deep depression of fluorescence intensity for azo dyes (such as acid orange Ⅱ). When azo-bone of azo dyes is broken down by electro-fenton, their fluorescence intensity increases dramatically, and this phenomenon is the unique features of azo dyes.

    Jan. 01, 1900
  • Vol. 31 Issue 5 530002 (2011)
  • Yang Changhu, Ma Zhongquan, and Yuan Jianhui

    Transparent and conductive c-axis oriented aluminum-doped zinc oxide (AZO) films have been prepared on glass substrate by DC magnetron sputtering processing. For this purpose, a sintered ceramic disc of ZnO mixed with Al2O3 is used as the target. The microstructure of AZO ceramic target is characterized by micro-Raman spectroscopy. The structural, optical and electrical properties of the films are characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), UV-visible spectrophotometer and four-probe tester respectively. As the substrate temperature increases, the results show that grain size of the AZO films gradually increases, the films have a strong c-axis orientation and the crystallization of films becomes better. The absorption edge has a blue shift with increasing deposition temperature. The refractive index of the films decreases but films thickness and optical band gap increase with increasing deposition temperature. Resistivity of AZO films decreases with increasing deposition temperature but resistivity approaches stable after substrate temperature reaches 350 ℃.

    Jan. 01, 1900
  • Vol. 31 Issue 5 531001 (2011)
  • Ding Wenge, Yuan Jing, Li Wenbo, Yang Yanbin, Yu Wei, and Fu Guangsheng

    Considering the quantum confinement effect in silicon nanoparticles, the effect of the mean silicon nanoparticle size on optical band gap, optical transition oscillator strength, and the temperature dependence of optical absorption, a model is introduced to analyze the optical absorption of silicon-nanostructure thin film with a certain size distribution of silicon nanoparticles. The results show that the band gap increases and the absorption spectra curves are shifted vertically with increasing temperature, which is like in bulk silicon. The comparative analysis of the simulation results and experimental data of optical absorption implies that our model can well explain the absorption of silicon-nanostructure thin film in the region of absorption edge.

    Jan. 01, 1900
  • Vol. 31 Issue 5 531002 (2011)
  • Yang Haigang, Song Guilin, Wang Tianxing, You Tianyou, and Chang Fanggao

    Nickel oxide thin films have been prepared by direct current(DC) reactive magnetron sputtering from a metallic Ni target in an Ar and O2 mixed atmosphere. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) have been used for the study of the crystal structure and to detect binding energy of different chemical states. Scanning electron microscopy (SEM) observations reveal a dense fine-grained structure with the grain size about 10 nm. Both Ni2+ and Ni3+ ions exist in the NiOx films. The films exhibit anodic electrochromism, and the coloration and bleaching of NiOx film are associated with insertion and deinsertion of Li+, OH- ions and electrons in the NiOx film. In addition, electrochromic performance and response time of NiOx film have been investigated. Results indicate that the modulation range of the visible optical transmittance can reach 47%, the colored response time is 9 s, and the bleached response time is 1s.

    Jan. 01, 1900
  • Vol. 31 Issue 5 531003 (2011)
  • Xiong Xicheng, Xie Quan, and Yan Wanjun

    Combined with the solar spectrum, the photon absorption coefficient of the β-FeSi2 thin film has been analyzed, and then the thickness of the absorption layer of β-FeSi2 thin film solar cell has been analyzed and theoretically calculated. The results show that, under the condition of the β-FeSi2 thin film with high quality, when the optical absorption efficiency of the solar energy radiation reaches 90%, the absorption layer thickness of the β-FeSi2 thin film solar cell is at least 200 nm and the best thickness range is from 200 to 250 nm. The calculation result has been verified by some relative experimental studies. At the same time, the formula for the relation between the absorption layer thickness of the β-FeSi2 thin film solar cell and the solar photon wavelength has been obtained.

    Jan. 01, 1900
  • Vol. 31 Issue 5 531004 (2011)
  • Sun Tianxi, Liu Zhiguo, Li Yude, Lin Xiaoyan, Luo Ping, Pan Qiuli, Liu Hehe, Yuan Hao, and Ding Xunliang

    The identification technology of plastic evidence is very important in forensic sciences. The X-ray energy spectra as a fingerprint of the plastic evidence is proposed to identify non-destructively the plastic evidence. The parallel capillary X-ray lens (PCXRL) is designed, and the X-ray fluorescence spectrometer based on the PCXRL and the laboratory X-ray source is developed to obtain the X-ray energy spectra as the fingerprint of the plastic evidence. The minimum detection limit of this X-ray fluorescence spectrometer is in the range of 1~35 ng/cm2. The diameter and the gain of full beam focused by the PCXRL are 3066 μm and 12.7 at 17.4 keV, respectively. There is a plateau where the distribution of the X-rays is uniform in the center of the focused beam. The diameter and the gain of this plateau is 570 μm and 47.5 at 17.4 keV, respectively. These are helpful to identify efficiently the plastic evidence with various sizes. The PCXRL has potential application in the identification technology for plastic evidence.

    Jan. 01, 1900
  • Vol. 31 Issue 5 534001 (2011)
  • Wu Xudong, Shi Junsheng, and Yun Lijun

    A new set of corresponding-colors data between monitor and printer is obtained from a series of visual color matching experiments, and the data′s reliability is analyzed with deviation. The new corresponding colors data and the Braun and Fairchild data are used to test the performance of three chromatic adaptation transforms (i.e. Von Kries, CMCCAT2000 and CAT02) and the CIECAM02 color appearance model. The results show that Von Kries and CMCCAT2000 have the same performance, the CMCCAT2000 gives more accurate prediction than the CIECAM02, and the CIECAM02 gives more accurate prediction than the CAT02. The results are not consistent with the performance of three chromatic adaptation transforms and the CIECAM02 in predicting the corresponding colors for the same media. Previous study of chromatic adaptation transform and CIECAM02 use mainly the corresponding colors data for the same media. The new set of corresponding colors data and the results will provide a reference for the improvement of chromatic adaptation transforms and color appearance model of CIECAM02.

    Jan. 01, 1900
  • Vol. 31 Issue 5 533001 (2011)
  • Chen Baomei, Zhao Baosheng, Hu Huijun, Sheng Lizhi, and Yan Qiurong

    Several new methods to improve the time accuracy and resolution based on the original X pulsar navigation ground simulation system are proposed. By these proposed methods, the accuracy and real-time performance of the spacecraft navigation has been enhanced. The methods adopted include: 1) enhancing the performance of the photon counting detector based on micro-channel plate (MCP); 2) using time measurement system with high accuracy. The pulse profile of the original detection system is compared with the pulse profile of the improved detection system, and the gain of MCP which has influence on the detected pulse profile is discussed. The experimental results show that the counting rate of improved detection system becomes higher under the same experimental condition. When the operating voltage of MCP is -800 V in the improved detection system, and the value of Bin is 1.5 ms, a pulse profile with good signal-to-noise ratio (SNR) can be acquired after being integrated for 200 s.

    Jan. 01, 1900
  • Vol. 31 Issue 5 534002 (2011)
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