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Chinese Journal of Aeronautics 2009年第4期22卷 426-433页

作者： Gao Yang Academy of opto-electronics,Chinese Academy of Sciences,Beijing 100190,china Academy of opto-electronics Chinese Academy of Sciences Beijing 100190 China

Low-thrust Earth-orbit transfers with 10^- 5-order thrust-to-weight ratios involve a large number of orbital revolutions which poses a real challenge to trajectory optimization. This article develops a direct method to optimize minimum-time low-thrust many-revolution Earth-orbit transfers. A parameterized control law in each orbit, in the form of the true optimal control, is proposed, and the time history of the parameters governing the control law is interpolated through a finite number of nodal values. The orbital averaging method is used to significantly reduce the computational workload and the trajectory optimization is conducted based on the orbital averaging dynamics expressed by nonsingular equinoctial elements. Furthermore, Earth＇s shadowing and perturbation effects are taken into account. The optimal transfer problem is thus converted to the parameter optimization problem that can be solved by nonlinear programming. Taking advantage of the mapping between the parameterized control law and the Lyapunov control law, a technique is proposed to acquire good initial guesses for optimization variables, which results in enlarged convergence domain of the direct optimization method. Numerical examples of optimal Earth-orbit transfers are presented.

关键词： low thrust orbital transfer optimization direct method orbital averaging Lyapunov method

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A Method for Obtaining Three-dimensional Images with Visual Reality of Real Objects

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Chinese Journal of Lasers 1999年第5期8卷 425-430页

作者： HUANG Qiong SU Xianyu(Department of opto-electronics, Sichuan University, Chengdu 610064, china) 四川大学光电子系四川成都 610064 四川大学光电子系四川成都

A new method to remove the shadows in laser triangulation and a computer model for three-dimensional images with visual reality of three-dimensional diffuse objects are presented. The methods for acquiring color data in optical three-dimensional sensing are discussed A method for obtaining three-dimensional images with visual reality of real objects is presented The principles, the system structure and the experimental results are provided.

关键词： three-dimensional sensing laser triangulation shadow three-dimensional images with visual reality

The Detection of Defects in Optical Fibers Using a Hybrid opto-electronic Correlator

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Chinese Journal of Lasers 2000年第3期9卷 15-21页

作者： LIU Yange LIU Wei ZHANG Yimo ZHOU Ge (College of Precision Instrument and opto-electronics Engineering, Tianjin University opto-electronic Information Science and Technology Lab., Tianjin 300072, china) 天津大学光电信息技术科学开放实验室天津

A hybrid opto-electronic correlator for detecting defects i n optical fibers is proposed. After the light from a He-Ne laser being expanded and filtered it is not collimated but directly passes a Fourier transform lens and illuminates a reference fiber and a test fiber at the same input plane. The Fourier transform spectrum of the two fibers is therefore obtained at the rear focal plane of the lens, where it is sampled via a CCD array connected with a computer through a frame grabber. The computer performs filter, inverse Fourier transform and setting threshold operation on classification. The system is an equivalent of joint transform correlator with a Fourier lens of long focal length. The experiment results for optical fibers having incoordinate defects are presented. The results indicate that the system can be used for fiber defect detection, and has the advantages of high identification, compact configuration, easy adjustment and flexible manipulation.

关键词： joint transform correlation Fourier transform optical fiber defect detection

Experimental Study on Semiconductor Optical Amplifiers with Angled Facets

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Chinese Journal of Lasers 1999年第1期8卷 8-11页

作者： DUAN Zigang HUANG Dexiu LIU Deming ZHANG Zemin (Department of opto electronics Engineering, Huazhong University of Science and Technology, Wuhan 430074, china) 华中理工大学光电工程系湖北武汉 430074 华中理工大学光电工程系湖北武汉

１ＩｎｔｒｏｄｕｃｔｉｏｎＳＯＡｗｉｌｂｅｏｎｅｏｆｔｈｅｋｅｙｃｏｍｐｏｎｅｎｔｓｉｎｔｈｅａｌｏｐｔｉｃａｌｎｅｔｗｏｒｋｉｎｔｈｅｆｕｔｕｒｅ．ＳＯＡｈａｓｍａｎｙｖｅｒｙｉｍｐｏｒｔａｎｔａｐｐｌｉｃａｔｉ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＳＯＡｗｉｌｂｅｏｎｅｏｆｔｈｅｋｅｙｃｏｍｐｏｎｅｎｔｓｉｎｔｈｅａｌｏｐｔｉｃａｌｎｅｔｗｏｒｋｉｎｔｈｅｆｕｔｕｒｅ．ＳＯＡｈａｓｍａｎｙｖｅｒｙｉｍｐｏｒｔａｎｔａｐｐｌｉｃａｔｉｏｎｓ，ｓｕｃｈａｓｗａｖｅｌｅｎ...

关键词： tilted cavity antireflective coating gain semiconductor optical amplifier

Optical 3D shape measurement for dynamic process

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optoelectronics Letters 2008年第1期4卷 55-58页

作者： SU Xian-yu, ZHANG Qi-can, and XIANG Li-qun opto-electronics Department, Sichuan University, Chengdu 610064, china opto-electronics Department Sichuan University Chengdu China

3D shape dynamic measurement is essential to the study of machine vision, hydromechanics, high-speed rotation, deforma- tion of material, stress analysis, deformation in impact, explosion process and biomedicine. in recent years. In this paper, the results of our research, including the theoretical analysis, some feasible methods and relevant verifying experiment results, are compendiously reported. At present, these results have been used in our assembling instruments for 3D shape measurement of dynamic process.

关键词：光检测技术光学三维形状测量动态过程机器视觉

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Theoretical Investigation of Potassium Faraday Dispersion Optical Filter at 766 nm

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Chinese Journal of Lasers 1999年第5期8卷 407-411页

作者： ZHANG Yundong CHANG Zhiwen BI Yong JIA Xiaoling MA Zuguang WANG Qi(Harbin Insititute of Technology, Institute of opto-electronics, Harbin 150001, china) 哈尔滨工业大学光电所黑龙江哈尔滨 150001 哈尔滨工业大学光电所黑龙江哈尔滨

A potassium Faraday dispersion optical filter (FDOF) is theoretically studied for the 4P3/2 ← 4S1/2 transition including hyperfine effects. The optimum filter operating condition is also obtained. The sinle peak bandwidth of the optical filter is about 0. 86 GHz and equivalent noise band width is 2. 4 GHz. The transmission is approximately 94. 1% percent under the optimum condition.

关键词： Faraday dispersion optical filter Transmission band-width

A　High　Efficient　Stable　Intracavity　Doubling　Nd：YAG　Laser　Pumped　by　a　Laser　Diode

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Chinese Journal of Lasers 1995年第4期B4卷 295-300页

作者： ZHANG Kuanshou XIE Changde GUO Ringxiang PENG Kunchi(Institute of opto- electronics ,Shanxi University,Taiyuan 030006) Shanxi Univ Taiyuan China

ＡＨｉｇｈＥｆｆｉｃｉｅｎｔＳｔａｂｌｅＩｎｔｒａｃａｖｉｔｙＤｏｕｂｌｉｎｇＮｄ：ＹＡＧＬａｓｅｒＰｕｍｐｅｄｂｙａＬａｓｅｒＤｉｏｄｅ￥ＺＨＡＮＧＫｕａｎｓｈｏｕ；ＸＩＥＣｈａｎｇｄｅ；ＧＵＯＲｉｎｇｘｉａｎｇ；... 详细信息

ＡＨｉｇｈＥｆｆｉｃｉｅｎｔＳｔａｂｌｅＩｎｔｒａｃａｖｉｔｙＤｏｕｂｌｉｎｇＮｄ：ＹＡＧＬａｓｅｒＰｕｍｐｅｄｂｙａＬａｓｅｒＤｉｏｄｅ￥ＺＨＡＮＧＫｕａｎｓｈｏｕ；ＸＩＥＣｈａｎｇｄｅ；ＧＵＯＲｉｎｇｘｉａｎｇ；ＰＥＮＧＫｕｎｃｈｉ（Ｉｎｓｔｉｔ...

关键词： intracavity harmonic Nd:YAG laser LD pumped laser

THz source based on optical Cherenkov radiation

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Science china(Information Sciences) 2012年第1期55卷 27-34页

作者： YAO JianQuan1,2,LIU PengXiang1,2,XU DeGang1,2,LV YingJin1,2&LV Da1,2 1Institute of Laser&optoelectronics,College of Precision Instruments and opto-Electronic Engineering,Tianjin University,Tianjin 300072,china 2Key Laboratory of opto-electronics Information Technology(Tianjin University),Ministry of Education,Tianjin 300072,china Institute of Laser & optoelectronics College of Precision Instruments and Opto-Electronic Engineering Tianjin University Tianjin China Ministry of Education Key Laboratory of Opto-electronics Information Technology (Tianjin University) Tianjin China

Terahertz(THz)technique has attracted considerable interest due to its broad application *** source is a crucial part of THz science and *** Cherenkov radiation in electro-optic crystals is a promising method of THz generation,because phase-matching is automatically *** this paper,we introduced two types of THz source based on optical Cherenkov radiation:both broadband and tunable *** mechanism of radiation was analyzed and recent development was reviewed in *** future of THz source based on optical Cherenkov radiation was also forecasted.

关键词： Terahertz source optical rectification dierence frequency generation Cherenkov radiation

Design and Implementation of a Virtual Multi-channel Optical Ring

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Chinese Journal of Lasers 2001年第6期10卷 12-17页

作者： JING Wencai ZHOU Ge ZHANG Yimo LI Haifeng ZHANG Hongxia (College of Precision Instrument & opto-electronics Engineering, Tianjin University, Key Laboratory of optoelectronics Information Technical Science, EMC, Tianjin 300072, china) 天津大学精密仪器与光电子工程学院教育部光电信息技术科学重点实验室天津 300072

The hardware and the communication protocol of a scalable optical ring have been designed. A hardware routing has been achieved on the network interface card to minimize data packet communication latency and a simplified communication protocol has been designed to reduce communication overheads. To reduce the data packet blocking probability and have a more efficient usage of the data link layer bandwidth, a virtual multi-channel transmission mechanism has been achieved. The network supports a maximum of 16 virtual channels for each physical data link. Time slots can be dynamically assigned to each virtual channel. Zero wait time has been achieved for the switching between different virtual channels.

关键词： communication protocol scalable optical ring hardware routing virtual multi-channel transmission time slot