Acta Photonica Sinica
Co-Editors-in-Chief
Yue Hao
WANG Peng-fei, DOU Ru-hai, and CHEN Jian-guo

Semiconductor laser as an example,using the form of end-reflection coefficient and traveling wave rate equations,an analytical expression relating the average photon density inside the cavity and the output photon density of the semiconductor laser is derived to establish the relation between the average photon density inside the cavity and the output density of the laser in a self-consistent fashion of the rate equations based on mean-field approximation (MFREs) .The result is that ratio of the output field and the average field inside the cavity is related to the pumping current.The ratio cannot be considered as a constant.

Aug. 24, 2021
  • Vol. 39 Issue 3 385 (2010)
  • ZHOU De-chun, YU Feng-xia, LU Jing-juan, and TAN Fang

    By means of numerical analysis method,the influences of many factors on output threshold pumped and output powers were analyzed,such as fiber length and back cavity lens reflectivity.These results provide theoretical foundation for optimized design of all-fiber laser device.Yb-doped all-fiber laser device with stable narrowed spectral linewidth laser output was made successfully,using fiber gratings as feedback and frequency-selected cavity lens.Tapered fiber realizes low-loss conncection between pumped module and Yb-doped double cladding fiber,and high effective pumped laser output power transmission.The stable laser output can be gained in this test,of which the wavelength is 1 082.50 nm,spectrometric width is 0.113 nm,the largest stable laser output power is 8.5 W,pumped threshold power is 0.8 W,and slope effectivity is 70.8%.

    Aug. 24, 2021
  • Vol. 39 Issue 3 389 (2010)
  • SUN Zhi-hong, XIA Yan-wen, LIU Hua, and LI Ke-yu

    Based on the requirement of the clean narrower second harmonic probe pulse, the Slip Step Fourier method is used to analyze the frequency doubling process in the third-order noncollinear correlator.The evolution characteristics of temporal profile are simulated for the Gaussian pulses and type I phase-matched of KDP crystal.The range of fundamental incident laser energy can be acquired with the second harmonic pulse shape remaining the Gaussian distribution.The pulse width of the third-order autocorrelation differences with the different ratios of full width of half maximum of fundament to second harmonic pulse at the different conversion efficiency of frequency doubling.This leads to the variable convolution factor of pulse width concerned with the pulse shape.The analyzing results are of reference value for the parameter design and error evaluating of the third-order autocorrelator.

    Aug. 24, 2021
  • Vol. 39 Issue 3 393 (2010)
  • GONG Yuan, LI Bin-cheng, GAO Li-feng, and HAN Yan-ling

    An optical feedback cavity ring-down (OF-CRD) technique,based on the OF effect of diode laser,was developed for accurate high-reflectivity measurement of cavity mirrors.The amplitude of the OF-CRD signal was enhanced to be about two orders of magnitude larger than that without OF effect.The high-reflectivity of the cavity mirror,measured by the OF-CRD at four RDC lengths,is in excellent agreement and statistically determined to be 99.935 6±0.000 8%.The OF-CRD and pulsed-CRD techniques,both based on the exponential decay measurement,were experimentally compared.The measurement accuracy of the OF-CRD is much higher than that of the pulsed-CRD,due to higher beam-propagation losses caused by mode-mismatching and mode beating effects in the pulsed-CRD experiment.

    Aug. 24, 2021
  • Vol. 39 Issue 3 397 (2010)
  • CHEN Bao-dong, and WEN Jing

    The influence of the polarization direction of light-induced refractive index change(Δn) induced by light irradiation in In:Fe:LiNbO3 crystals were investigated by using ordinary and extraordinary recording polarization(opol/epol) laser beams of low-power near infrared light.The experimental results show that the curves are similar of the refractive index distribution,but they have opposite signs,and a further difference is that the saturation refractive index change is clearly larger for ordinary recording polarization,changing to extraordinary recording polarization result only about one-third.The refractive index change in photorefractive crystals induced by two polarization directions of near infrared light is differ from visible light.The crystal illuminated with extraordinary polarized light in the middle of the irradiation region,one can see a strong increased of the refractive index.Moreover,the results can be very useful for fabrication of tailored nonlinear optical device with different refractive index distributions by changing different the polarization directions of near infrared beam.

    Aug. 24, 2021
  • Vol. 39 Issue 3 403 (2010)
  • LUAN Ling, and FENG Li-jun

    An active-passive method is used in discrete chaotic systems to study chaos synchronization.A discrete system is generally divided based on Lyapunov stability theory,and synchronization of discrete chaotic systems is realized.Bragg acousto–optic bistable system is taken as an example to verify the effectiveness of the method.Simulation results show that the error variable of two Bragg acousto–optic bistable systems with different initials approach zero smoothly and rapidly in a short series of time,which shows the method is effective and practical.The method is proper to any discrete or continuous chaotic systems with different initials,and it can be generally used.

    Aug. 24, 2021
  • Vol. 39 Issue 3 409 (2010)
  • MENG Yi-chang, ZHANG Shu-min, JIN Chun-jiang, LI Hui-hui, and WANG Xin-zhan

    The generation and compression of parabolic similariton pulses are investigated numerically,and a novel method of generating high-energy femtosecond pulses is obtained.The results show that the high-energy parabolic pulses with linear chirp can be obtained by propagating of pulses inside the Erbium-doped fibers.Employing the linear compression with hollow core photonic bandgap fibers in the first stage and the nonlinear compression with highly nonlinear fiber in the second stage,the parabolic similariton pulse can be compressed into a femtosecond pulse with high peak power.There is an optimum fiber length for the pulse compression,and the Raman self-frequency shift and the self-steepening effects are disadvantageous for pulse compression.

    Aug. 24, 2021
  • Vol. 39 Issue 3 412 (2010)
  • YANG Ji-chao, and SONG Mu-ping

    Waveguides′ dispersion characteristics are studied.The conclusion shows that if changing the slot′s structural parameters,the value of the slot waveguide′s dispersion is also changed when the optical frequency is around 1.55 μm,and the values are all smaller than -1 000 ps/(nm·km).The minimal one is about -6 700 ps/(nm·km),and its Relative Dispersion Slope is smaller than 0.009 nm-1.By selecting suitable slot′s structural parameters,silicon slot waveguide could be used to compensate the residual dispersion of optical communication link,and it has more advantage than DCF.

    Aug. 24, 2021
  • Vol. 39 Issue 3 417 (2010)
  • GENG Rui, LU Yu-chun, LIU Chu, ZHANG Fan, WANG Chun-can, and JIAN Shui-sheng

    Based on the nonlinear,time-dependent radiation transfer equations,which describe the amplification process of a pulse and account for the effect of the radiation on the medium and vice versa,the power characteristics of the output pulses of a Yb-doped fiber amplifier are investigated under different input pulse shapes.Numerical results show that,the power gain of the pulse traversing the amplifier is different for different shapes when the average energy of the input pulse is the same.This difference is larger in the leading part of the pulse,which leads both the gain value and the shift value of the peak power for the output pulses to be dependent on the input pulse shape.Especially,when the input pulse energy is relatively large,the gain of the peak power for different pulses is obviously different; with Super Gaussian pulse the largest followed by Gaussian pulse and Hyperbolic-Secant pulse and Lorentzian pulse the smallest.

    Aug. 24, 2021
  • Vol. 39 Issue 3 423 (2010)
  • HAO Xiao-fei, ZHAO Hui, and HAO Dong-shan

    Using the quantum perturbation theory and model of the multi-photon nonlinear Compton scattering,the optically controlled switching for spatial soliton in multi-channel planar waveguide system under Compton scattering is studied.The result shows that in the nonlinear planar optical waveguide with a sinusoidal modulation of the refractive index in the transverse direction,the soliton can be cut between a channel and near channel,through the pinch soliton wave beam effect in the transverse direction of the cross phase modulation between the soliton in the channel,and control optical point formed by the incident optical and scattered optical,and the function of the soliton switching is attained.The control optical point can be attained by the transverse direction focusing of the coupling optical between a potential valley and near potential valley.The threshold of the effective intensity of the control optical point and the radiation loss of the soliton can be increased by the scattered optical,the potential wall high is increased,and the littler extent is reduced.These are all beneficial to the soliton form,the wide unfolded by the scattering of the soliton wave beam is bigger,and the danger destroyed by the scattering to the soliton switching is existing too.Therefore, the control appropriate incident laser intensity is the key for the attaining soliton switching.

    Aug. 24, 2021
  • Vol. 39 Issue 3 427 (2010)
  • JIN Qing-li, YAN Li-fen, and WANG Zhen-guo

    A real-time solution concentration monitor based on Fabry-Perot interferometer is designed.The concentration variation measurement is realized by the F-P interferometer and optical fiber to transmit the image to the CCD.The relation between the variation of interference fringes of the F-P interferometer and the fluctuation of solution concentration is analyzed.The monitor system consists of He-Ne laser,optical fiber,planar F-P interferometer,arrayed CCD and PC is set up.Three different glycerin solution are used to verify the system design,and the experiment shows the system can provide a resolution on the order of 10-4 concentration variation.

    Aug. 24, 2021
  • Vol. 39 Issue 3 431 (2010)
  • TAN Lu-wen, LI Jing-zhen, LU Xiao-wei, and YANG Fan

    A driving circuit design of TCD1707D was presented.It could overcome the shortcoming of common circuit which is needed to change the hardware or programme in case the condition has been modified.This design shows two flexible working modes,one is internal burst mode,the other is external burst mode.In the external burst mode,the users can control the time of exposure and signal outputs by means of external triggered pulse.Integration time and driving frequency of CCD can be tuned simultaneously in the other mode.The function is carried out by setting internal and external triggered respectively with complex programmable logic device (CPLD) and an external control.CPLD is combined with the control circuit,so external commands can produce corresponding control signals to drive curcuit nomally.And then through the pins of CPLD,the output signals can be transfered to the CCD chip.In addition,in order to solve the EMC problem,the article presents a linear CCD periphery circuit,which is improved the quality of CCD signal outputs.This method has the advantages of convenient debugging,simple circuit and high integration level.It is proved by experiments that the system outputs basically match the simulation,and the signal outputs are more reliable,more stable and less interferential than common system.And the system could fulfill a wide range of users’ needs,especially can be used for accurate high-speed measurement and push-broom.

    Aug. 24, 2021
  • Vol. 39 Issue 3 436 (2010)
  • WANG Bo, BAI Yong-lin, OU-YANG xian, LIU Bai-yu, BAI Xiao-hong, and ZHAO Jun-ping

    Ultra-high-speed dynamic spectrum of the various transient detection has become the main means of access to information.However,due to the the characteristics of high transmission and temporal resolution in spectrum data acquisition system,the CCD must have real time output,the data is large,and a high speed acquisition system is required.A CCD data acquisition system based on FPGA is designed.The whole system is controlled by FPGA,which is used to supply CCD timing and controls signal disposal,storage and transmission of data.Finally the data is transferred by USB bus into computer to do further processing to get a complete explosion spectral information.With this system four time temperatures during 100 ns detonation can be measured,and the results show that the system has a higher measurement accuracy and speed,which can be achieved high-speed spectral information collection and storage during the explosion.It also can be applied to other transient information acquisition.

    Aug. 24, 2021
  • Vol. 39 Issue 3 441 (2010)
  • FANG Ping, YANG Zhi, WANG Yi-shan, ZHAO Wei, ZHANG Ting, and LI Cheng

    To research the mechanism of high power supercontinuum generation by sub-nanosecond pulse pumping photonic crystal fiber (PCF),a 1.8 m PCF is pumped by 570 ps pulses from a Yb-doped mode-locked fiber laser,and it puts out SC (supercontinuum) with 1.15 W power and 750 nm spectral coverage.It is verified that when SC is generated by sub-nanosecond pulse pumping 1.8 m PCF,the modulation instability (MI) takes an important part in expanding spectrum via comparing and analyzing the experiment with simulation.After researching the change of SC under different pump power,it is found that the power of SC increases and the spectral coverage expands with the pump power.Under watt power output,it still does not reach saturated section,and be probable to get higher power and broader spectrum.

    Aug. 24, 2021
  • Vol. 39 Issue 3 446 (2010)
  • ZHU Gui-xin, YU Tian-bao, CHEN Shu-wen, LIAO Qing-hua, LIU Nian-hua, and HUANG Yong-zhen

    Two photonic crystal waveguides with triangular lattice of air holes together,between which there are three rows of air holes,are put in parallel to construct a directional coupler.The propagation of TE(electric field parallel to the axis of the air holes) and TM(magnetic field parallel to the axis of the air holes) polarizing lights in the proposed directional coupler is analyzed numerically.The results show that the coupling length of TE light is reduced whereas the coupling length of TM light do not change when the radius of one row of the dielectric rods between the two waveguide of the coupler are modified.On the basis of this structure,ultracompact polarizing beam splitter is designed and the length of the device is only 10.1 μm.Compared with the previous results of 24.2 μm,this device is smaller and more efficient.

    Aug. 24, 2021
  • Vol. 39 Issue 3 450 (2010)
  • YANG Xin-jun, WU Hua-xia, YU Xiao-fen, DONG Dai, and WANG Zhao-qi

    An optical system for airborne Helmet Visor Display(HVD) is designed according to characteristics of the airborne helmet and requirements of man-machine engineering. The optical performance and distortion model are analyzed,and the distortion correction algorithm and software are presented to reduce the distortion of the designed optical system. Experimental results show that after correcting the distortion for the designed optical system,a high imaging quality is achieved,the MTF approaches 0.2 at the spatial frequency of 50lp/mm,and the full field of view distortion is less than 0.5%.The results meet the demands of airborne Helmet Visor Display(HVD).

    Aug. 24, 2021
  • Vol. 39 Issue 3 455 (2010)
  • WANG Guo-xiang, NIE Qiu-hua, WANG Xun-si, XU Tie-feng, DAI Shi-xun, SHEN Xiang, and ZHU Ming-xing

    (100-x)(80GeS2-20Ga2S3)-xKI(x=0,10,20 mol%) chalcohalide glasses are prepared by traditional melt-quenching method.The differential thermal analysis(DTA),visible/near-infrared absorption spectroscopy,infrared transmission spectra are adopt to the analysis of the relationships of the composition,structure and properties of the GeS2-Ga2S3-KI ternary glass system.The results show that:the glass-forming regions of GeS2-Ga2S3-KI ternary system glasses are fairly big.When the content of KI is 10 mol%,the glass is of the best thermal stability.With the addition of KI,there has been no significant change in infrared cut-off wavelength of the glasses which are all 12.5 μm.While with the local field potentials increasing,the short-wave absorption of the glasses shifts to the shorter wavelength and the optical band gap increases.

    Aug. 24, 2021
  • Vol. 39 Issue 3 460 (2010)
  • WANG Da-gang, ZHOU Ya-xun, DAI Shi-xun, WANG Xun-si, SHEN Xiang, XU Tie-feng, and NIE Qiu-hua

    Er3+/Ce3+ codoped tellurite glasses(TeO2-Bi2O3-TiO2) are prepared by conventional melt-quenching method.The thermal stability of the glass is studied by the DTA(Differential Thermal Analysis) technique,and the absorption spectra,up-conversion spectra and the fluorescence spectra of the Er3+ ion are measured and analyzed with the different Ce3+ ion doped concentration.The results show that the tellurite glass has good thermal stability,and the difference(ΔT =Tx-Tg) between the glass transition temperature Tg and the crystallization onset temperature Tx has came to 185℃,which is higher than the other reported results.The energy transfer from Er3+ ion to Ce3+ ion(Ce3+∶2F5/2+Er3+∶4I11/2→Ce3+∶2F7/2 +Er3+∶4I13/2) aroused by Ce3+ ion codoping can suppress the upconversion emission and improve the 1.53μm band emission intensity efficiently.And,the emission cross-section of Er3+ ion increases with the increasing content of Ce2O3.The excellent thermal stability and spectral properties indicate that Er3+/Ce3+ codoped tellurite glass is a promising gain host material for broadband erbium-doped amplifiers.

    Aug. 24, 2021
  • Vol. 39 Issue 3 464 (2010)
  • LI En-ling, ZHU Hong, LI Li-sha, QI Wei, LI Xiao-ping, and WANG Jin-yu

    The B3LYP method of Density Functional Theory(DFT) is used to optimize geometry configuration of GanN3(n=1~8) clusters at the level of 6-31G*.The bond properties,photoelectron energy spectroscopy and stability are calculated and analyzed,and the most stable structures are obtained finally.The results show that there is a transition from planar to spacial structures at n=5 with increasing cluster size,and N-N bonds are more stable.The strong Ga-N bonds play an important role in GanN3(n=6~8).Among the GanN3(n=1~8) clusters,Ga4N3,Ga7N3 are more stable; Average polarizabilities are increased as the n value increases.The vibrational frequencies of Ga-N bond are close to the peaks of the phonon vibration modes of the wurtzite structure GaN by analyzed the photoelectron energy spectroscopy.

    Aug. 24, 2021
  • Vol. 39 Issue 3 470 (2010)
  • XU Guo-sheng

    To solve the crossing-linkable polyethylene(XLPE) insulation compound purity evaluation problem,a high speed scanning measurement system is designed according to Linear CCD technology.The inspecting system of defects in cable materials based on CCD obtains signals of defects in cable materials with irradiation of parallel light,by using linear array CCD control circuit.The defect signals are collected and transferred by using virtual oscillograph DSO-2902,and the defect signals are analyzed and processed by using computer.The defects are precisely figure out.The data of signals memorized in computer are processed by using software system of data collecting,the data quantity to be processed is decreased greatly,while the contamination information data are reserved.Thereby,the inspection of precise size and location of defects are achieved.The experiment results show that the proposed system can measure both the transverse and the longitudinal size of the XLPE contamination particle well and truly,and also detect the accurate positions and the number of a certain kind of impurity particle.The acuity of this system can reach 20 μm and the error ratio is less than 5%.The detecting ratio of the contamination particles can be high up to 100%.

    Aug. 24, 2021
  • Vol. 39 Issue 3 477 (2010)
  • LI Zhi-quan, ZHU Guo-fang, CHEN Xi, YANG Qiu-xia, LIU Shi-yuan, YAN Ju-bing, and LI Wen-chao

    The dual-loop carbon monoxide concentration measurement system is introduced based on the sensing principle of fiber loop ring-down spectroscopy technology.The important role of erbium fiber amplifier and the influence of its gain fluctuation on the system are analysed.According to the feedback gain control of the erbium fiber amplifier,stability and precision of the system are further enhanced.The ring-down curves corresponding to different CO concentrations are obtained through experiments.Then,the absorption characteristics of different concentrations and the ralationship between ring-down time and concentration are also analysed,all of which provide an important reference for the high accuracy gas concentration on-line measurement.

    Aug. 24, 2021
  • Vol. 39 Issue 3 481 (2010)
  • WU Xu-hua, XIA Jiang-tao, XIAO Shao-rong, and CHEN Lei

    Through absolute liquid reference method,the bend static liquid surface dynamics equation is built for calibrating the system error of interferometer,and theoretical simulation and experimental measurement are carried out for wetting effect on liquid surface.The stability of liquid surface effected by the environment factors such as air current,temperature,vibration,is analyzed,the experiment is taken,and estimate indexes are given.The absolute liquid reference with high-accuracy is set for calibrating interferometer system error under laboratory environment,the results are given,and the measurement accuracy is ensured.

    Aug. 24, 2021
  • Vol. 39 Issue 3 485 (2010)
  • WU Yi-ming, GAO Li-min, LI Ming, CHEN Liang-yi, and ZHAO Jun-li

    Aiming at measurements of glass material inner-stress,a new high precision measurement method is proposed using the Magnetic-Optic Modulation technique for the stress birefringence.The proposed method has the strong points that simple theory,high precision and so on.The theory derivation is also given using the Jones Matrix,and the results show that the two methods to improve measurement efficiency are feqsible when the testing sample is much bigger.

    Aug. 24, 2021
  • Vol. 39 Issue 3 490 (2010)
  • LIU Peng, GAO Li-min, and ZHAO Su-wen

    The measuring principle of the grating autocollimator is discussed based on vertical stripes Moiré detection.Using the Fourier optics theory,it is able to deduce that the method is feasible which uses the linear array CCD to replace the instructions grating to produce moiré fringes in the autocollimator.The experiment validates that when the ratio s between projection grating constant d2 on CCD and grating constant d1 equals to 1.01,the amplification ratio of the vertical moiré fringes can reach to 14.14.The proposed method can solve the problem that the grating diffraction affects the trial result,simplify the autocollimator optical system,and enhance the system′s resolution.

    Aug. 24, 2021
  • Vol. 39 Issue 3 494 (2010)
  • WANG Fei, GE De-biao, and WEI Bing

    The finite-difference time-domain(FDTD) method is extended to two-dimensional magnetic anisotropic dispersive media-magnetized ferrite by using Shift Operator(SO).It is proved that when the incident plane wave vector is perpendicular to the axis of the two-dimensional axial magnetized ferrite cylinder,the electromagnetic wave can be decomposed into Transverse Electric(TE) and Transverse Magnetic(TM) waves.The electromagnetic scattering characters of TE wave have no relation with the target,but the electromagnetic scattering characters of TM wave have close relations with the electromagnetic parameters in magnetized ferrite.The physical reasons are analyzed.The FDTD with shift operator(SO-FDTD) formulations in this case are derived based on the constitutive relation for magnetized ferrite and shift operator,which leads to the electromagnetic wave propagation of both anisotropy and frequency dispersion media being solved at the same time.For the electromagnetic scattering of Von Karman shaped conducting cylinder coated with anisotropic magnetized ferrite,the effect of the ferrite parameters on the bistatic Radar Cross Section(RCS) is investigated and some numerical results are obtained.The results indicate that an appropriate ferrite coating may efficiently reduce the RCS of a metallic target,and expjωt denotes the convention of time dependence.

    Aug. 24, 2021
  • Vol. 39 Issue 3 499 (2010)
  • LI Ying-le, WANG Ming-jun, DONG Qun-feng, and TANG Gao-feng

    Based on the scales theory of electromagnetic wave,the law of electric field inside and outside an anisotropic medium sphere is researched.The formula of scattering field from the anisotropic targets is derived.The differential scattering cross section and the scattering amplitude etc.for the anisotropic spherical target are presented.The correctness of the obtained results is tested.Simulation results show that the scattering of an anisotropic sphere has the property of a dipole radiation.The bigger the dielectric constant is,the stronger the dipole and the scattering are.These results provide a theoretical basis for the light scattering from an anisotropic target and the identification of anisotropic targets.

    Aug. 24, 2021
  • Vol. 39 Issue 3 504 (2010)
  • AN Ying, YAO Cheng, QIAO Xiao-Fen, GAO Dang-li, TIAN Yu, CUI Min, and ZHENG Hai-rong

    In order to investigate the influence of Yb3+concentration on the up-converted blue fluorescence intensity of Tm3+ ions,the fluorescent materials of Tm3+ and Yb3+ codoped LaF3 nanoparticles are prepared using hydrothermal method with NaF and La(NO3)3 as raw materials.The result of X-ray diffraction shows that the crystal structure of the prepared nanoparticles is hexagonal.The image of the transmission electron microscopy suggents that the particles are uniformly distributed and have a good dispersity.Up-converted blue emissions at 474 nm and 450 nm,which correspond to the transitions of 1G4→3H6 and 1D2→3F4 respectively,are observed when the samples are excited with 800 nm lasers.The influence of Yb3+ concentration on the fluorescence properties of Tm3+ ions is investigated by adjusting the Yb3+ concentration in Tm3+/Yb3+:LaF3 nanoparticles.It is found that for fluorescence emission at 474 nm,when the concentration of the Yb3+ increases,the fluorescence intensity also increases due to inverse energy transfer process.But the fluorescence intensity will decrease after it reaches a certain value.For the fluorescence emission at 450 nm,its intensity does not change obviously with the concentration of Yb3+ ions,but its fluorescence intensity is increasing firstly and then decrease like 474 nm fluorescence.

    Aug. 24, 2021
  • Vol. 39 Issue 3 508 (2010)
  • SONG Wei, TAO Shi-Quan, and WANG Huan-yong

    The influence of wavefront quality of reference beams on the reconstruction quality of holographic recordings is investigated by numerical simulation.A physical model of recording and readout of Fourier transform holograms is built up to study reconstruction quality with various reference waves such as general plane wave,Gaussian wave and speckle wave.The quality is quantitatively evaluated using the loss of signal to noise ratio(LSNR)of the readout images.The simulation results show that plane and Gaussian reference waves could successfully record and readout high-quality holographic images with LSNR lower than 0.6 dB,but the speckle reference led to quality deterioration of reconstructed images with LSNR as high as 5 dB.It will be difficult to realize effective high-density data storage by speckle reference beam.In order to implement high-quality and high-density holographic storage,the reference beam must be optimized.

    Aug. 24, 2021
  • Vol. 39 Issue 3 513 (2010)
  • GUO Chun-hua, YU Jia, WANG Jin-cheng, HAN Zheng-ying, WANG Tian, and YANG Yu

    For making white reproduction, large viewing zone, full-parllax synthesis holograms, the direct writing method is put forward. Based on the digital image processing technology and the principle of stereogram hologram, the experiment produced a hologram with a large viewing zone of 57°.And holograms have achieved a 1×1 m2 large-scale splicing.

    Aug. 24, 2021
  • Vol. 39 Issue 3 518 (2010)
  • QIAN Xiao-fan, WANG Zhan-liang, ZHANG Hai-tao, and CHEN Hong

    In traditional digital holography,the measurement of amplitude of vibration is realized by detecting the intensity distribution of reconstructed image,and satisfied results can not be obtained.The phase of the first kind zero-order Bessel function has binary values,zero and π,thus,the distribution of amplitude of vibration can be measured through the phase of reconstructed wave.Theoretical analysis demonstrates that the phase change caused by the shift of illuminated light is ignored in discussion before.In this study,this method is corrected by overlapping a phase factor and a new method is put forward to eliminate the effects of this factor by utilizing the phase characteristics of squared Bessel function.Experiment shows that,this phase factor not only exist,but also influence final measurement.Using proposed method,this influence can be eliminated very well.Moreover,it will bring convenience into the measurement of amplitude of vibration via the phase of reconstructed wave in time-average digital holography.

    Aug. 24, 2021
  • Vol. 39 Issue 3 523 (2010)
  • LI Yong, XU Fu-yang, JIN Hong-zhen, and WANG Hui

    The mathematical model of Fresnel hologram is analyzed,and it is found that the speed bottleneck of generating CGH is the operation of square and trigonometric function.A method for fast computation of Fresnel hologram is proposed.The mathematical model of Fresnel hologram is transformed to the form which is expressed as the four arithmetic operations of components related to horizontal direction and vertical direction of hologram,according to trigonometric identity.Then,the great amount of operation of square and trigonometric function is replaced by little amount of operation of square and trigonometric function and great amount of arithmetic operation.The computational amount of Fresnel hologram is reduced and the computational speed will be increased clearly.The experimental results show that the speed of Fresnel hologram computation is accelerated over 9 times by using the method of separation of variables.

    Aug. 24, 2021
  • Vol. 39 Issue 3 529 (2010)
  • ZHANG Wen, ZHOU Hao, GU Ji-hua, YANG Jun-yi, JIANG Jin-hu, and GAO Ben-li

    The technology of multi-beam digital hologram is proposed to the problem that due to the influence of the illumination,CCD only can receive a little weak scattered wave from the lateral surface of the object,so that it can not reconstruct the multi-surface of the object clearly and brightly at the same time.The proposed method points out that it can use multi-beam to illuminate several surfaces of three-dimensional object.It enhances the intensity of the scattered wave received by CCD from the lateral surface of the object.Multi-surface of three-dimensional object is reconstructed successfully in this experiment.Then,in order to reduce speckle noise of the reconstruction image,is bilinear interpolation and median filter is adopted to process the image,and high quality reconstruction image of three-dimensional object is acquired.

    Aug. 24, 2021
  • Vol. 39 Issue 3 533 (2010)
  • ZHU Yan, GU Yong-jian, XU Zhou, XIE Lin, and MA Li-zhen

    A scheme is proposed for the physical realization of a quantum probabilistic cloning machine.First,with two superconducting quantum interference devices (SQUIDs) embedded in a high-Q cavity used as the original and target qubits respectively,and the cavity field as the measurement qubit,the unitary evolution required for the cloning machines is realized through multiple interactions of SQUID with the cavity or classical microwave pulses.Then the state reduction is implemented by mapping the cavity state onto another SQUID and measuring the magnetic flux of the SQUID,thus realizing the exact cloning of quantum states with optimal success probability.In this scheme,two–photon Raman resonance process is used to increase the single qubit operation rate,and the total operation time is far less the time of spontaneous decay and cavity decay.Therefore this scheme is experimentally feasible.

    Aug. 24, 2021
  • Vol. 39 Issue 3 537 (2010)
  • WANG Pu-yu, and YANG Guo-jian

    The influence of atomic coherence on the formation of a ultracold molecule from ultracold two-state atoms is discussed via photoassociation.By using the method of quantum statistics,it is found that under the action of atomic coherence,the molecular number vibrates with an approximate period and with reduced amplitude.Atomic coherence has a strong influence on the temporary of the whole photoassociation process,but the molecules are always subject to sub-Poisson statistical distribution.

    Aug. 24, 2021
  • Vol. 39 Issue 3 543 (2010)
  • LUO Hai-bo, SHI Ze-lin, and CHEN Yong-hong

    To deal with the problem that traditional real-time correlation tracking methods are sensitive to the light variation, a Phase Congruency(PC) image based on tracking method is proposed which utilizes the properties of PC function falling in [0, 1] interval, being normalized and invariant to changes of image brightness and constrast. PC detection is performed on the original image, and PC image is obtained. Subsequently, target tracking with correlation tracking methods, such as Minimum Absolute Difference (MAD) is conducted on the PC image. Experiment results show that the proposed method can achieve a satisfactory tracking performance on visible light images and infrared images even though the image brightness and constrast vary abruptly.The phase congruency image based on tracking method can be used to solve the common problems of tracking point drifting, even failed tracking due to image light variation in traditional real-time correlation tracking methods.

    Aug. 24, 2021
  • Vol. 39 Issue 3 547 (2010)
  • SHI Shi-ming, WANG Ling-xue, JIN Wei-qi, and ZHAO Yuan-meng

    In order to acquire color night vision images accordant with human perception,and help observers to get more abundant scene information,a kind of color night vision method based on color transfer in multi-decomposition structure is proposed.Concerning their characteristics,low-level light visible and IR images are combined into a color fused image (source image) based on opponent vision property in YUV color space.Then the steerable pyramid is used to decompose the fused image and a colorful day-time reference image into multi-scale sub-band images.The mean and standard deviation of each sub-band image are calculated.Each sub-band coefficient of source image is modified according to the deviation ratio of the reference image to the source image in respective color channels.Finally,reconstruct the transferred image and obtain a low-level light visible/IR color night vision image with comfortable color appearance similar to the reference image.The transferred results in lαβ,YUV and RGB space are analyzed.YUV space is recommended to be the best color space for multi-decomposition color transfer.Comparing with traditional linear color transfer,the proposed method can make a color night vision image more realistic and natural,enhance the details,improve the situation perception and target detection ability.

    Aug. 24, 2021
  • Vol. 39 Issue 3 553 (2010)
  • XU Xiao-zhao, CAI Yi-heng, LIU Xiao-min, LIU Chang-jiang, and SHEN Lan-sun

    The grey world algorithm is discussed in detail,and two improved grey world algorithms are proposed,to overcome the limit that the algorithm may be ineffective in the case of few colors or large union colors image which are based on standard deviation weighted algorithm and based on image entropy constraint algorithm respectively.The algorithms are evaluated in two aspects: the color correction results are compared subjectively (visually),and the performance is evaluated objectively using color difference data.The experimental results show that the improved algorithms have better correction effect on both real capture images and downloaded images.

    Aug. 24, 2021
  • Vol. 39 Issue 3 559 (2010)
  • WANG A-ni, MA Cai-wen, and MA Dong-mei

    A new method for moving object auto-extraction is presented in the field of moving object detection and tracking.The background model is initialized using filtered image frames,which have been stored,and the background is updated continuously by the result of object detection in the process of moving object detection.The moving region is obtained by the difference of current frame and the background.Then the adaptive threshold is used to get binary image and link the edge.The outlines of moving regions in binary image are extracted,and false outlines are eliminated resulted from noise and imprecise background by enacting area threshold value according to the size of moving object.Boolean calculation is done to the original image with the mask image including outlines of moving region and the result of extraction is obtained.The experiment results show that the method can well extract rigid body and nonrigid body can be extracted well by the presented method.

    Aug. 24, 2021
  • Vol. 39 Issue 3 565 (2010)
  • ZOU Wei-jun, GONG Xiang, and BO Yu-ming

    For the particle′s sampling and optimization of particle filter in video object tracking,an adaptive layered-sampling auxiliary particle filter is proposed to realize the tracking precision and robustness′s requirement.A function which adjusts the particle amount is designed based on the Baattacharyya coefficient.According to the tracking quantity,it can allocate the particles keeping precision and the particles keeping robustness adaptively in the particle set.A predicted point of object-moving based on the LSM (least square method) algorithm is used to be the origin to do the meanshift operation.By this operation,the new particle set is made,it will be better to describe the object′s likelihood distribution and improve the algorithm efficiency.The tracking experiments under different enviroments demonstrate that this algorithm can achieve better tracking performance in presence of occlusion and object-moving in slow and variable direction,the consuming time is up to the requiment of real-time performance.

    Aug. 24, 2021
  • Vol. 39 Issue 3 571 (2010)
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