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First Application of Single-Shot Cross-correlator for Characterizing Nd:glass Petawatt Pulses

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Chinese Physics Letters 2013年第2期30卷 99-102页

作者： WANG Yong-Zhi OUYANG Xiao-Ping MA Jin-Gui YUAN Peng XU Guang QIAN Lie-Jia Department of Optical Science and Engineering Fudan UniversityShanghai 200433 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesJiading DistrictShanghai 201800 Key Laboratory for Laser Plasmas and Physics Department Shanghai Jiaotong UniversityShanghai 200240

We report the first application of a single-shot cross-correlator for pulse duration and pulse contrast diagnostics in Nd:glass petawatt *** information of pulse duration,measured in the single-shot,guides the fine adjustment of the pulse compressor in real *** integrating several shots of measurements at different time delays together,the petawatt pulse profile is obtained within an overall temporal window of~100 ps,indicating a contrast of~10^(4).The measurements suggest that the additional contrast improvement is necessary for the Nd:glass petawatt laser system,which should be different from conventional Ti:sapphire lasers and is also discussed.

关键词： Nd: pulse correlator

LiNbO_3/p^+n diode surface acoustic wave memory correlator

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Science China(Technological Sciences) 1997年第5期40卷 497-504页

作者：张朝水永安印建华 Institute of Acoustics Nanjing University Nanjing 210093 China

A detailed theoretical analysis of strip-coupled LiNbO3/p+ n diode surface acoustic wave (SAW) memory correlator in the parametric mode is presented. The influence of some important factors on correlation output is analyzed and calculated, including the amplitudes of reference, read and write signal, duration of write signal and doping density of the diode array. The conclusions can be employed for the design of improved strip-coupled SAW memorycorrelators.

关键词： memory correlator diode array SAW tapped delay line minority carrier lifetime.

Simple optical decryption based on a modified joint transform correlator technique

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Journal of Harbin Institute of Technology(New Series) 2006年第2期13卷 203-205页

作者：王怀彬王天佐袁晓聪 School of Computer Science & Technology Tianjin University of Technology Tianjin 300191 China School of Computer Science & Technology Harbin Institute of Technology Harbin 150001 China School of Electrical & Electronic Engineering Nanyang Technological University Nanyang Avenue 639798 Singapore

A new encryption/decryption system for optical information security is proposed in this paper. We used an iterative Fourier transform algorithm to optimize the encrypted hologram as well as the decryption key as phase-only elements. The optical decryption was implemented by superimposing the encrypted hologram and the decryyption key in a simple optical setup. Numerical simulation and optical experiment have confirmed the proposed technique as a simple and easy implementation for optical decryption, demonstrating potential applications in optical information security verification.

关键词： computer generated holograms correlator encryption/decryption

Phase-shifting technique applied to circular harmonic-based joint transform correlator

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Chinese Science Bulletin 2000年第20期45卷 1908-1912页

作者： Jiuhong Guan Zhaoqi Wang Hongli Liu Baolai Liang Guoguang Mu Nankai Univ Inst Modern Opt Minist Educ China Optoelect Informat Sci & Technol Lab Tianjin 300071 Peoples R China

The phase-shifting technique is applied to the circular harmonic expansion-based jointtransform correlator. Computer simulation has shown that the light efficiency and the discrimination capability are greatly enhanced, and the full rotation invariance is preserved after the phase-shifting technique has been used. A rotation-invariant optical pattern recognition with high discrimination capability and high light efficiency is obtained. The influence of the additive noise on the performance of the correlator is also investigated. However, the anti-noise capability of this kind of correlator still needs improving.

关键词： joint transform correlator phase-shifting technique circular harmonic expansion.

Optically fixed photorefractive correlator

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Chinese Physics B 2002年第7期11卷 710-713页

作者：刘友文刘立人 ShanghaiInstituteofOpticsandFineMechanics ChineseAcademyofSciencesShanghai201800China

An optically fixed photorefractive correlator is presented, where two-centre non-volatile holographic recording isemployed to write and fix the matched filter in doubly doped LiNbO3 crystals. This correlator shows good correlationcharacteristics and insensitivity to the writing beam during readout. It can be used in cases requiring stability and notrequiring modification for a long period, and it is refreshed optically when new information needs to be registered.

关键词： photorefractive effect two-centre non-volatile holographic recording correlator doublydoped LiNbO3 crystals

Wideband Demodulator Based on Five-Port correlator for Channel Sounding Applications

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Journal of Electromagnetic Analysis and Applications 2013年第2期5卷 79-84页

作者： Imen Sfar Lotfi Osman Ali Gharsallah 不详

We present in this paper a wideband RF demodulator using a five-port correlator and a power detector for channel sounding applications. The demodulator has been fabricated using microstrip components. The correlator receives from the five-port qualities that allow it to be low-cost and less sensitive to the phase and amplitude imbalances. A calibration procedure is proposed to find the complex envelope of the RF signal applied at the input of the five-port correlator. Simulation with Advanced Design System software and measurement results have been conducted to demonstrate its capabilities as a RF signal demodulator operating in a wideband around 2.4 GHz frequency.

关键词： Calibration Procedure Channel Sounder Diode Power Detector Five-Port correlator

Factorial correlator data from pp collisions at 400GeV/c

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Science China Mathematics 1996年第12期39卷 1304-1311页

作者：王韶舜李祖豪张杰肖臣国叶云秀 (Department of Modern Physics University of Science and Technology of China Hefei 230027 China)

The factorial correlators have been calculated by using the experimental data of the pseudorapidity distribution of the charged particles produced in pp collisions at 400GeV/c. The results show that the factorial correlators increase with the decrease of the correlation distance independently of the pseudorapidity resolution. The existence of the sum rules between the factorial moments and factorial correlators has been tested by using the experimental data.

关键词： factorial moment factorial correlator log-normal approximation.

Optical　correlator　and　Photorefractive　Two－wave　Mixing　Based　Neural　Recongnition

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Chinese Journal of Lasers 1996年第2期 167-172页

作者： FU Xiaoli LI Yulin (Xi'an Institute of Optics and Fins Mechanics ,Academy of Sinica ,Xi' an 710068, China)

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关键词： optical neural networks pattern recognition correlator nonlinear wavemixing

Image Encryption Based on a 1-D Joint Transform correlator

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Semiconductor Photonics and Technology 1999年第1期5卷 58-60,64页

作者： XULin LIAimin NanjiangUniversityofScienceandTechnology Nanjiang210094CHN NanjiangUniversityofScienceandTechnology

A method for image encryption using a 1-D joint transform correlator is described. By use of line functions, a 2-D object is encrypted first in one direction, then in the perpendicular direction. The principle of the ... 详细信息

关键词： correlator Cryptography Optical Information Processing