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    Saturated Echo Signal Algorithm for Wide Dynamic Range Lidar
    ZHU Shi-xian, ZHAO Yi-qiang, YE Mao, LI Jie, XIA Xian-zhao, XIE Shao-yu, ZHOU Guo-qing
    Acta Photonica Sinica    2018, 47 (12): 1228003-1228003.   DOI: 10.3788/gzxb20184712.1228003
    Abstract478)      PDF (2448KB)(852)       Save

    An adaptive window width centroid correction algorithm is proposed based on echo signal modeling for lidar distance detection. An adaptive window width model is established to obtain centroids based on the relationship between window width and saturation. The algorithm is adjusted by the median, and achieves high-accuracy time extraction of saturated waveforms. The simulation is carried out through Matlab, and the results show that when the SNR reaches 10 dB, the accuracy of the adaptive window width centroid correction algorithm is 0.3 ns. Compared with traditional waveform centroid algorithms, the accuracy of the proposed algorithm is improved by 92% and the problem of centroid drift can be effectively solved. The algorithm is verified utilizing board-level measured waveforms and is corrected for distortion of the measured waveforms, the results show that the time accuracy of algorithm can reach 0.5 ns, and ranging accuracy can achieve 7.5 cm in case of saturated waveforms. The proposed algorithm can effectively increase the dynamic range of ranging and reduce system complexity.

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    Electromagnetic Induced Transparency Based on All-dielectric Metasurface
    HU Sen, LIU Dan, YANG He-lin
    Acta Photonica Sinica    2018, 47 (11): 1116001-1116001.   DOI: 10.3788/gzxb20184711.1116001
    Abstract541)      PDF (5829KB)(772)       Save

    Classical analogy of electromagnetically induced transparency-like effect was demonstrated by a all-dielectric metasurface structure based on TiO2, which composed of two cross perpendicular dielectric bars and four dielectric bricks. Under the excitation of incident electromagnetic field, electric Mie resonance, which is directly excited by the incident electromagnetic field in the dielectric bar, can excite the magnetic Mie resonance in the dielectric bricks by the interaction of each other, and then produce the destructive interference between the resonant modes, thus the phenomenon of electromagnetic induced transparency occurs. By using the simulation software and the "two oscillators" coupled model, the simulation calculation and quantitative analysis of the electromagnetic induced transparency effect were both carried out. Results show that a transparent window with a transmittance of nearly 96% is generated at 0.552 THz under the normal incidence of electromagnetic wave. Owing to its C4 rotation symmetric and multiple dark mode resonant elements of the proposed structure, the induced transparency effect is characterized by a broadband transparency window and insensitive to the incident electric field polarization.

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    Coupling Efficiency and Influence Factors of Spatial Light into Few-mode Fiber
    WANG Chao, FAN Xue-bing, TONG Shou-feng, LI Ying-chao, JIANG Lun, LIU Zhuang, SHI Hao-dong, JIANG Hui-lin
    Acta Photonica Sinica    2018, 47 (12): 1206001-1206001.   DOI: 10.3788/gzxb20184712.1206001
    Abstract508)      PDF (2324KB)(736)       Save

    The coupling efficiency theory model of the spatial light into few-mode fiber in the different influence factor is established. Takes two-mode fiber for example to study the relative aperture effect on coupling efficiency. When the relative aperture is 0.17, the highest coupling efficiency is 82.96%. The coupling efficiency in the presence of tilt, defocus and random angular jitter is studied, the experiment show that when the lateral offset is 4 μm, the coupling efficiency of two-mode fiber is higher than single-mode fiber about 10.23%, when the axial offset is 125 μm, the coupling efficiency of two-mode fiber is higher than single-mode fiber about 11.24%, when the random jitter amplitude is 5 μm, the coupling efficiency of two-mode fiber is higher than single-mode fiber about 12.1%. Accordingly, the few-mode fiber can inhibit interference factor such as tilt, defocus and random angular jitter when the signal reception.

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    Optical System of the Hyper-spectral Imager for the Underwater Environment and Targets Monitoring
    YU Lei, XU Ming-ming, CHEN Jie-xiang, XUE Hui
    Acta Photonica Sinica    2018, 47 (11): 1101003-1101003.   DOI: 10.3788/gzxb20184711.1101003
    Abstract824)      PDF (4638KB)(707)       Save

    The observation method is analyzed and the performances parameters of corresponding spectrometer are obtained based on the characteristic spectrums of the major elements in the underwater environment. The telescope and the imaging spectrometer are separately designed and coupled together. The telescope adopted double Gauss refractive system and realized optimization of the telecentric design with few optical materials. The imaging spectrometer based on the Dyson mounting also performed excellently with the analysis of optical path and the added lenses. The final design obtained the excellent performances that the field of view is 28°, the F number is 3, the spectral resolution is 3.5 nm, and the spatial resolution is 1 mrad in the waveband of 350~700 nm. The prototype verified the design theory.

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    Optical and Electrical Properties of Two-dimensional MoS2 and Pentacene/MoS2 Heterojunction
    BAI Zhi-ying, DENG Jin-xiang, PAN Zhi-wei, ZHANG Hao, KONG Le, WANG Gui-sheng
    Acta Photonica Sinica    2018, 47 (12): 1231001-1231001.   DOI: 10.3788/gzxb20184712.1231001
    Abstract318)      PDF (3371KB)(648)       Save

    Using sulfur powder and MoO3 powder as raw materials, the MoS2 film was synthesized by chemical vapor deposition method, and was characterized by optical microscopy, atomic force microscopy, raman spectroscopy and X-ray diffraction. Results show that the crystal morphology of the MoS2 is triangle with size of 60 μm and thickness of 0.7 nm; and as one kind of the ideal substrates for surface-enhanced Raman scattering, two-dimensional MoS2 can promote the charge transfer between the organic molecule and MoS2, so the Raman intensity of them are enhanced. The pentacene was adsorbed onto the MoS2 film by physical vapor deposition method, and the organic-inorganic pentacene/MoS2 heterojunction with ideal rectifier characteristic was prepared. Analysing the ln(I/V2)-1/V curve, it is seen that the Fowler-Nordheim tunnelling phenomenon occured through the heterojunction; logI-logV curve shows that charges transport controled by ohmic conduction at 0~1 V voltages zone, and space-charge-limited currents predominate at over 1 V voltages zone. The research of MoS2 single-layer film and pentacene film will be contributed to the optoelectronic field.

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    Ion Beam Etching Assisted Femtosecond Laser Machining to Manufacture Silicon Carbide Micro-optical Components
    YU Lei, YANG Shuang-ning, LIU Xue-qing, LI De-hui
    Acta Photonica Sinica    2018, 47 (12): 1214003-1214003.   DOI: 10.3788/gzxb20184712.1214003
    Abstract618)      PDF (6093KB)(575)       Save

    A hybrid technology combined ion beam etching and femtosecond laser machining was proposed for solving the problem of high surface roughness when processing of hard materials by femtosecond laser machining. First, silicon carbide micro/nano structures were fabricated by femtosecond laser machining. Then, the silicon carbide micro/nano structures were etched by ion beam etching. Ion beam etching can adjust the width and depth of the line structure, and reduce the surface roughness of the structures from about 106 nm to 11.8 nm. The silicon carbide Fresnel zone plate prepared by this technology exhibits well focusing and imaging properties.

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    Chip of Phase Control Arrays Based on Silica on Silicon
    YAN Yue-wu, AN Jun-ming, ZHANG Jia-shun, WANG Liang-liang, LI Jian-guang, WANG Hong-jie, WU Yuan-da, YIN Xiao-jie, WANG Yue
    Acta Photonica Sinica    2019, 48 (4): 423001-0423001.   DOI: 10.3788/gzxb20194804.0423001
    Abstract825)      PDF (3473KB)(562)       Save

    A silicon-based silica optical waveguide phased array chip was designed and fabricated.The chip consisted of three parts,including a beam splitting unit,a phase modulation unit and an output waveguide array.The splitting unit was cascaded by three 1×2 optical beam splitters.The phase modulation unit adopted the method of thermo-optic modulation,and the output part comprised 8 dense array waveguides.Light output from 8 waveguides formed interference in the far field,becoming scanning beam.Passing through the thermal photo-effect of the silica after power-on,when the refractive index changed by 0.027%(0.000 4),the scanning beam changed by 5.5°.The waveguide phased array adopted 2.0% ultra-high refractive index difference silicon-based silica waveguide as material,which was fabricated by material growth and annealing by plasma enhanced chemical vapor deposition and then etched by inductive coupled plasma dry etching technology,and finally cut and polished.The test results show that the static output of the eight output array waveguides forms a clear interference spot.When voltage is up to 130 V,the scanning beam angle changes by 5.5 °.

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    Performance of Oceanic Wireless Optical Communication Systems Based on Orbital Angular Momentum Multiplexing with Spatial Diversity
    YIN Xiao-li, SUN Zhi-wen, CUI Xiao-zhou, ZHENG Zi-jian, CHEN Xiao-zheng, GUO Yi-lin, LIAO Huan-yu, LIU Guang-yao
    Acta Photonica Sinica    2018, 47 (11): 1106003-1106003.   DOI: 10.3788/gzxb20184711.1106003
    Abstract438)      PDF (4862KB)(556)       Save

    In oceanic wireless optical communication systems based on orbital angular momentum multiplexing, oceanic turbulence will bring the channel crosstalk. To solve the problem of channel crosstalk, a spatial diversity mitigation scheme is proposed. Random phase screen method is used to simulate phase perturbation caused by ocean turbulence and split-step transmission method is used to simulate the beam diffraction. Equal gain diversity combination is used to process signal at the receiver. 4-orbital angular momentum-multiplexed channels and 8-spatial diversity are used in the system. The influences of orbital angular momentum mode sets, oceanic turbulence strength and communication distance on the bit-error rate are investigated. Simulation results show that bit error rates decrease obviously with the modes spacing increases from 1 to 2 in the orbital angular momentum multiplexed sets. Performances of bit-error rates remain steady as modes spacing become larger. Bit-error rate will also increase with the increasing transmission distance and turbulence strength. Results show using diversity combination on orbital angular momentum-multiplexed systems can effectively mitigate the performance degradation from oceanic turbulence.

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    Fabricating Blue Phosphorescent Organic Light-emitting Devices by Using B3PyPPM as Electron Transport Layer
    LIN Wen-yan, YU Ye, PENG Xue-kang, JIN Yu, WU Zhi-jun, LIU Jing-hua
    Acta Photonica Sinica    2018, 47 (12): 1223001-1223001.   DOI: 10.3788/gzxb20184712.1223001
    Abstract402)      PDF (3476KB)(547)       Save

    We fabricated blue phosphorescent organic light-emitting devices of A and B groups by using B3PyPPM as electron transport layer and TCTA and mCP as host. The structure are:ITO/HATCN(5 nm)/TAPC(45 nm)/TCTA:FIrpic(15%,15 nm)/B3PyPPM(X nm)/B3PyPPM:Cs(15%,10 nm)/Al and ITO/HATCN(5 nm)/TAPC(45 nm)/mCP(5 nm)/mCP:FIrpic(15%,15 nm)/B3PyPPM(X nm)/B3PyPPM:Cs(15%,10 nm)/Al. The values of X are 40 nm, 45 nm, 50 nm, and 55 nm, respectively. Experiments show that the devices which use mCP as host is far better than the device using TCTA as host. The maximum luminance of 14 930 cd/m2 and the maximum current efficiency of 9.9 cd/A are obtained. The efficiency roll-off in EQE is only 10.1% when the luminance rises from 500 cd/m2 to 3 000 cd/m2. Since B3PyMPM can improve the injection characteristics of electrons, the turn-on voltage of the two groups devices are 2.3 V and 2.8 V, respectively, which is lower than the Firpic blue phosphorescent OLEDs fabricated with other electron transport layer materials. At the current density of 30 mA/cm2, the spectra of all devices have a major peaks at 474 nm and a vibrational peak at 496 nm. As the thickness of B3PyPPM increases, the intensity of the shoulder increases due to the microcavity effect. The microcavity phenomenon existing in the device is studied in detail by optical simulation.

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    Study on Phase Matching Condition at Pump Depletion in Four-wave Mixing
    WAN Feng, WU Bao-jian, CAO Ya-min, XING Huan-xing, QIU Kun
    Acta Photonica Sinica    2019, 48 (2): 219001-0219001.   DOI: 10.3788/gzxb20194802.0219001
    Abstract674)      PDF (2245KB)(543)       Save

    The analytic method is used to analyze the range of quasi-phase matching and the evolution of the phase matching in the case of pump depletion, and the expression for the phase matching is given. The evolution process of four-wave mixing gain under pump depletion is compared to the case in small-signal approximation. In the case of pump depletion, with the increase of the transfer power, the linear mismatch factor corresponding to the total phase matching gradually tends to 0 and the quasi-phase matching range also becomes narrower. By determining the quasi-phase matching rang, the cascaded four-wave mixing process in wavelength division multiplex or space division multiplexing systems can be simplified for analysis. The small signal approximation model is only suitable for the case that the transfer power is far less than the pump power, and the linear mismatch factor at the total phase matching is not dependent on the length of the fiber.

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    Interface Engineering of Graphene/silicon Solar Cells by Introducing an Ultrathin Magnesium Oxide Interlayer
    ZHAO Jian-jiang, XU Ming-sheng
    Acta Photonica Sinica    2018, 47 (12): 1223002-1223002.   DOI: 10.3788/gzxb20184712.1223002
    Abstract312)      PDF (2819KB)(541)       Save

    In order to investigate the characteristics of the back-side surface, i.e., Al/Si, of graphene/Si solar cells, a ultra-thin magnesium oxide interlayer with various thickness between the Al electrode and the silicon substrate was prepared by using a successive thermal evaporation deposition technology. The current-voltage curves, external quantum efficiency, series resistance, and back contact resistance of the graphene/Si solar cells with different thickness of the magnesium oxide interlayer were measured. The results show that the photoelectric conversion efficiency, series resistance and back contact resistance increased first and then decreased with the increase in the magnesium oxide thickness, and the device performance is best when the thickness of magnesium oxide layer is 1 nm. The photoelectric conversion efficiency, series resistance and back contact resistance of the solar cells with 0 nm and 1 nm MgO are 2.90%, 4.2 Ω, 9.6 Ω, and 5.53%, 1.8 Ω, 3.2 Ω.

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    Automatic Phase Aberration Compensation for Digital Holographic Microscopy Combined with Phase Fitting and Deep Learning
    XIAO Wen, YANG Lu, PAN Feng, CAO Run-yu, YAO Tian, LI Xiao-ping
    Acta Photonica Sinica    2018, 47 (12): 1210001-1210001.   DOI: 10.3788/gzxb20184712.1210001
    Abstract441)      PDF (8170KB)(541)       Save

    An automatic aberration compensation method is proposed by combing phase fitting and deep learning in digital holographic microscopy and applications to dynamic observation of living cell morphology. Firstly, in the holography recording plane, the preliminary aberration compensation is implemented by using a digital phase mask, whose quadratic polynomial fitting computation is based on the extraction of reconstructed phase value along central cross line profiles in the field of view. Then, in the holographic imaging plane, the final aberration compensation is completed by using higher-order polynomial digital phase mask that computed with the phase data in the object free region, which is defined by the convolutional neural network. Thus, the phase image of object is correctly and accurately reconstructed. Thanks to the preliminary aberration compensation in the holography recording plane, the complexity of reconstruction in the holographic imaging plane is effectively reduced before the convolutional neural network training. Therefore, a stable deep learning model for phase image segmentation can be obtained on basis of limited data set and the compensation of phase aberration can be achieved without any manual intervention. The experiments are demonstrated by observing the several kinds of living cells, which have different morphological characteristics, with the off-axis digital holographic microscopy. Furthermore, the proposed method is applied to screen the drug resistance of endometrial cancer cells. These experimental results verify the proposed method and show that it can be used to dynamic microscopic observation in biological cell research.

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    Tunable High-frequency Millimeter-wave Signal Generator Based on Optical Carrier-suppressed Modulation
    LIU Ting-ting, PEI Li, WANG Yi-qun, WU Liang-ying, ZHENG Jing-jing, LI Jing
    Acta Photonica Sinica    2018, 47 (12): 1206003-1206003.   DOI: 10.3788/gzxb20184712.1206003
    Abstract356)      PDF (3751KB)(539)       Save

    A tunable multi-frequency optical millimeter-wave signals generator scheme based on optical carrier-suppressed modulation was proposed theoretically. Millimeter-wave signals with tunable frequency multiplication factor can be obtained through the beating of two sideband components of the optical carrier-suppressed signal which are selected by the uniform fiber Bragg grating based on acousto-optic tunable filter. What's more, in order to avoid the time shift of code effect caused by the chromatic dispersion of the fiber, the baseband data signals are modulated on only one sideband component of the optical carrier-suppressed signal. To investigate the scheme, some simulations have been done. It turns out that optical millimeter-wave signals with frequency multiplication factors of 2, 6, 10, 14, 18 and 22 will be generated. The transmission performance of the downlink of the radio-over-fiber system are also evaluated. Under the situation that the frequency multiplication factor is 22, when the optical millimeter-wave signals modulated with none-return-to-zero data signals of 2 Gbit/s, the eye diagrams are still wide open after transmitting through the fiber of 50km. Meanwhile, the power penalty is only 0.4 dB. The results show that the system with well transmitting performance can meet the requirements of communication.

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    Design and Properties Approach of an Integrated Interference Chip Made by Optical Waveguides
    ZHANG He-li, JIANG Huan, ZHANG Bing, REN Yi-tao
    Acta Photonica Sinica    2019, 48 (1): 123002-0123002.   DOI: 10.3788/gzxb20194801.0123002
    Abstract429)      PDF (2849KB)(538)       Save

    An optical waveguide interference chip with a multi-layer planar structure was designed, and the integrated chip was fabricated successfully after its structure and the material parameters were optimized using the mode theory of optical waveguide. Far-field interference fringes with a high contrast are achieved by the dual-guide waveguide structure inside the chip. Within an experimental error, experiments demonstrate that the interference fringe pattern generated from the integrated chip can be explained and predicted by Young's double-slit theory, and the fringe moves under a minor environment change. For humidity and alcohol gas, the detection sensitivity of the chip can reach about 100 ppm level with enough temperature stability during estimate test, which demonstrates its potential applications in sensing environment gas with low concentration and provides a new platform to develop an integrated gas sensor with high sensitivity.

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    Single Image Dehazing Algorithm Based on Fusion and Gaussian Weighted Dark Channel
    ZHANG Chen, YANG Yan
    Acta Photonica Sinica    2019, 48 (1): 110002-0110002.   DOI: 10.3788/gzxb20194801.0110002
    Abstract635)      PDF (6618KB)(532)       Save

    Aiming at the problem that the image dehazing algorithm has halo phenomenon in depth discontinuity and legacy residual fog in the distant area, this paper proposes a single image dehazing algorithm based on fusion and Gaussian weighted dark channel. Firstly, using the characteristics of image morphology gradient, the morphological gradient image and the dark channel image are linearly fused to obtain the fusion dark channel. Secondly, the adaptive Gaussian weight parameter is constructed to pixel-by-pixel process the fused dark channel image to obtain the coarse transmission, and the L1 regularization is used to optimize the transmission. Finally, the haze-free image is restored by the atmospheric scattering model and the restored atmospheric light value. Experimental results show that the proposed algorithm can recover the details of the image and suppress the halo phenomenon. The objective comparison with several typical algorithms proves the feasibility of the proposed algorithm.

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    Light Absorption Characteristics of AAO/Ag NPs Composite System
    JIANG Dong-hui, QU Jia, XU Xin, LIU Kun, SUN Wen-jun
    Acta Photonica Sinica    2019, 48 (1): 131001-0131001.   DOI: 10.3788/gzxb20194801.0131001
    Abstract563)      PDF (3895KB)(522)       Save

    AAO/Ag NPs light absorber model based on porous anodic aluminum oxide and silver nano particles was designed and analyzed by employing finite-difference time-domain method. AAO/Ag NPs composite samples were prepared by physical vapor deposition method, and the optical absorption curves of the samples with different experimental parameters were characterized and tested. Results show that the light absorbance of the AAO/Ag NPs composite is as high as 98% in the range of 400 nm to 2 500 nm, and the high light absorbance is almost independent of the oxidation of silver nano particles. Theoretical calculation and test results show that the more particles are deposited inside the porous anodic aluminum oxide hole, the deeper the particle deposition, the larger the silver nano particles size range, the higher the light absorbance. The porous anodic aluminum oxide template effectively reduces the reflectivity of incident light, and the Ag film on the surface of porous anodic aluminum oxide effectively reduces the loss of incident light.

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    High Responsiveness Multiply Carbon Nanotubes-organic Red Light Detector
    AN Tao, LIU Dan
    Acta Photonica Sinica    2019, 48 (1): 104001-0104001.   DOI: 10.3788/gzxb20194801.0104001
    Abstract311)      PDF (4039KB)(522)       Save

    A single-walled carbon nanotube combined with an organic red light material by a solution spin coating method to produce a red light detector.The influence mechanism of single-walled carbon nanotubes on PBDTTT-F:PCBM bulk heterojunction active layer film and the photoelectric properties of red photodetector were studied. The performance of the device was characterized and optimized by atomic force microscopy, fluorescence spectroscopy and ultraviolet-visible absorption spectroscopy.When single-walled carbon nanotube is the optimal doping ratio 1.5 wt%, the responsivity of the detector is 535 mA/W under the red light illumination, the detection reaches 3.8×1012 Jones, and the external quantum efficiency reaches 104%. The results show that the combination of single-walled carbon nanotubes and organic red-light materials can improve the aggregation and crystallinity of organic conjugated polymers and enhance the absorption of light, provide high-mobility charge conduction channels for the active layer and optimize the interpenetrating network morphology. At the same time, the multi-exciton generation effect of carbon nanotubes is utilized, the photoelectric performance of organic photoelectric detectors has been greatly improved, the external quantum efficiency exceeds 100%,Providing reference for further development of inorganic-organic photodetectors.

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    Study on Model of the Sea Surface Skin Temperature and Bulk Sea Surface Temperature in Northern Region of South China Sea
    ZHANG Jian, HAO San-feng, SONG Qing-jun, ZHAO Liang-xiao, AN Fei
    Acta Photonica Sinica    2018, 47 (11): 1101001-1101001.   DOI: 10.3788/gzxb20184711.1101001
    Abstract546)      PDF (2954KB)(510)       Save

    For the research of marine remote sensing calibration of China, a mathematical model of bulk-skin sea surface temperature is proposed to improve the measurement precision of skin sea surface temperature to 0.3℃. Skin sea surface temperature is measured by the self-designed automatic multi-spectral infrared radiometer system installed on the PY-301 oil platform in the northern part of the South China Sea, the measurement accuracy of the radiometer is better than ±0.5℃ through standard blackbody calibration, pupil correction and skylight correction. The effect of wind speed on the bulk-skin sea surface temperature is analyzed based on the model, the skin sea surface temperature is corrected by the proposed model and Donlon model, the biases of corrected results are -0.007 6±0.297 1℃ and 0.044 6±0.324 8℃, respectively. Results prove that the proposed model is effective and can improve the measurement accuracy of skin sea surface temperature.

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    Arc Measurement Method of Curved Surface Based on Monocular Vision System
    WU Fu-pei, GUO Jia-hua, LI Sheng-ping, YE Wei-lin, ZHANG Xian-min
    Acta Photonica Sinica    2018, 47 (11): 1112002-1112002.   DOI: 10.3788/gzxb20184711.1112002
    Abstract476)      PDF (3727KB)(508)       Save

    A curved surface measurement method based on monocular vision system is proposed to measure the curved surface of the special-shaped parts. First, the monochromatic vision system which is composed of a tricolor LED ring structure light source and a three-color CCD color camera is used to collect a single color image that contains the surface characteristics of the measured surface. Secondly, the correlation of color distribution features of the images, the regular of gray level variation and characteristics of adjacent regions are analyzed, and the segmentation method is designed to complete the target surface segmentation. Then, the calculation equation of the measured surface height is derived based on the image model of the monocular vision system and the related parameters of the material and the experimental environment. Finally, the height of the measured points is reduced by solving the height accumulation component between adjacent pixels. On this basis, the surface curvature measurement model is established and the curved surface is measured. The surface curvature measurement experiments respectively for 3D printing surface samples, screw thread and SIM card slot are carried out based on the proposed method. Comparing with the laser triangulation measurement method results, it shows that the errors are all less than 3.6%, the measurement accuracy is 0.000 1 rad, and the time length of measuring is less than 0.6 s. The experimental results show that the proposed method has good adaptability for measuring object edge, height abrupt change, height gradual change and other types of surface. It can achieve high precision measurement and fast measurement speed.

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    Modified Model of Polarized Bidirectional Reflectance Distribution Function on Material Surface
    WANG Jie-jun, WANG Peng, WANG Fang-yuan, YE Song, WANG Xin-qiang
    Acta Photonica Sinica    2019, 48 (1): 126001-0126001.   DOI: 10.3788/gzxb20194801.0126001
    Abstract580)      PDF (3324KB)(488)       Save

    A modified polarization bidirectional reflectance distribution function model was proposed based on the combination of the micro surface scattering model and the Kubel-Munk theory, which combines the mirror scattering and diffuse scattering to characterize the effect of the polarization scattering characteristics of the surface of the object on the extraction of the target polarization information. The mathematical model of complex refractive index, azimuth angle, detection angle and incident wavelength is used to inverse the complex refractive index of the base material. In combination with practical applications, a series of polarization detection experiments were carried out on the target surface under different influence factors by using FD-1665 polarimetric imager. Finally, the numerical simulation results are compared with the measured data. The polarization characteristic curve of the material is in agreement with the measured data. It shows that the revised model has high accuracy. The model can provide theoretical support for the follow-up polarization monitoring and target recognition.

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