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Retrieving Wave Parameters From GNSS Buoy Measurements Using the PPP Mode 期刊论文  OAI收割
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS, 2022, 卷号: 19, 页码: 5
作者:  Zhu, Lin;  Yang, Lei;  Xu, Yongsheng;  Yang, Fanlin;  Zhou, Xinghua
  |  收藏  |  浏览/下载：29/0  |  提交时间：2022/04/12
Design and analysis of performance of FSO communication system based on partially coherent beams 期刊论文  OAI收割
OPTICS COMMUNICATIONS, 2020
作者:  Wu, Yan;  Mei, Haiping;  Dai, Congming;  Zhao, Fengmei;  Wei, Heli
  |  收藏  |  浏览/下载：36/0  |  提交时间：2020/10/19
Exoplanet detection methods and transit spectrometer equipment of astronomical telescopes 会议论文  OAI收割
Xiamen, PEOPLES R CHINA, 2020-08-25
作者:  Wang Fang;  Fan Xuewu;  Wang Hu;  Shen Yang;  Pan Yue
  |  收藏  |  浏览/下载：20/0  |  提交时间：2021/06/04
Structural design of primary mirror subassembly for space telescope (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Mechatronics and Applied Mechanics, ICMAM 2012, December 8, 2012 - December 9, 2012, Taiwan
作者:  Xu H.
收藏  |  浏览/下载：63/0  |  提交时间：2013/03/25
In order to design a large aperture primary mirror with the diameter of 1150 mm  the parameters impacting on gravity deformation of the mirror were analyzed and discussed in detail  including material selection  diameter-thickness ratio  the number of the support points  location selection and lightweight structure  etc. A novel space mirror structure system was put forward  and its back was opened and supported by six points on back. The dynamic and static and thermal characteristics were analyzed based on the finite element method. Analysis results showed the surface figure accuracy reached to RMS 14.5nm under the action of gravity load along the optical axis direction and the first-order natural frequency was 214Hz which met to the designed indexes requirements. (2013) Trans Tech Publications  Switzerland.  
Structural amelioration of 920 nm optically pumped semiconductor vertical external-cavity surface emitting laser (OPS-VECSEL) (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Energy, Environment and Sustainable Development, EESD 2012, October 12, 2012 - October 14, 2012, Jilin, China
作者:  Liu Y.;  Liu Y.;  Wang L.;  Wang L.;  Wang L.
收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25
920 nm optically pumped semiconductor vertical external-cavity surface emitting laser (OPS-VECSEL) has an important application in laser display. We constructed and optimized a 920 nm OPS-VECSEL with active region of In0.09Ga0.91As quantum well (QW) system pumped by 808 nm laser diode module. By the finite element method  self-consistent solutions of the semiconductor electronic and optical equations are realized to calculate the characteristics parameters of OPS-VECSEL. The performances of device especially the mode  the threshold and the optical-optical translation efficiency were analyzed by dealing with different number of QWs (1  2 and 3) in one period  QW depth  barrier width  the component and dimension of the non-absorption layer. We chose an improved structure of them. On this basis  we ameliorated the number of QW periods and the simulation showed that in order to obtain high performance device  the choice of the number of QW periods must be cautious. (2013) Trans Tech Publications  Switzerland.  
The sequence measurement system of the IR camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  Zhang H.-B.;  Han H.-X.;  Geng A.-H.
收藏  |  浏览/下载：35/0  |  提交时间：2013/03/25
Currently  the IR cameras are broadly used in the optic-electronic tracking  optic-electronic measuring  fire control and optic-electronic countermeasure field  but the output sequence of the most presently applied IR cameras in the project is complex and the giving sequence documents from the leave factory are not detailed. Aiming at the requirement that the continuous image transmission and image procession system need the detailed sequence of the IR cameras  the sequence measurement system of the IR camera is designed  and the detailed sequence measurement way of the applied IR camera is carried out. The FPGA programming combined with the SignalTap online observation way has been applied in the sequence measurement system  and the precise sequence of the IR camera's output signal has been achieved  the detailed document of the IR camera has been supplied to the continuous image transmission system  image processing system and etc. The sequence measurement system of the IR camera includes CameraLink input interface part  LVDS input interface part  FPGA part  CameraLink output interface part and etc  thereinto the FPGA part is the key composed part in the sequence measurement system. Both the video signal of the CmaeraLink style and the video signal of LVDS style can be accepted by the sequence measurement system  and because the image processing card and image memory card always use the CameraLink interface as its input interface style  the output signal style of the sequence measurement system has been designed into CameraLink interface. The sequence measurement system does the IR camera's sequence measurement work and meanwhile does the interface transmission work to some cameras. Inside the FPGA of the sequence measurement system  the sequence measurement program  the pixel clock modification  the SignalTap file configuration and the SignalTap online observation has been integrated to realize the precise measurement to the IR camera. Te sequence measurement program written by the verilog language combining the SignalTap tool on line observation can count the line numbers in one frame  pixel numbers in one line and meanwhile account the line offset and row offset of the image. Aiming at the complex sequence of the IR camera's output signal  the sequence measurement system of the IR camera accurately measures the sequence of the project applied camera  supplies the detailed sequence document to the continuous system such as image processing system and image transmission system and gives out the concrete parameters of the fval  lval  pixclk  line offset and row offset. The experiment shows that the sequence measurement system of the IR camera can get the precise sequence measurement result and works stably  laying foundation for the continuous system. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Design of reimaging F/1.0 long-wavelength infrared optical system (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载：36/0  |  提交时间：2013/03/25
A reimaging F/1.0 long-wavelength infrared optical system is proposed. The design has a flexible opto-mechanical layout. The design process is as follows. Firstly  the catadioptric reimaging system consists of two reflecting mirrors and a relay lenses. Two reflecting mirrors make up of the first imaging system and are therefore free of chromatic aberrations  while low dispersion lenses were used in the reimaging system  so the optical system do not need achromatic design for a high image quality. Then  to correct high-order aberrations resulting from large relative aperture  more parameters need to be used with aspheric or diffractive surfaces due to modern optic technology development. Here  aspheric is selected for easily manufacture. Finally  the design is completed with the help of ZEMAX software. The effective focal length of the objective is 120mm and the field of view (FOV) is 4. The simulated final design shows adequate image quality and the modulation transfer function (MTF) is close to diffraction limit. The effect of the surrounding environmental temperature is analyzed using the concept of thermal defocusing  and the thermal compensation is discussed. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Simulation and experiment of the static FTIR based on micro multi-step mirrors (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, May 24, 2011 - May 26, 2011, Beijing, China
作者:  Liang Z.-Z.;  Zhang J.;  Zhang J.;  Zhang J.;  Zhu W.-B.
收藏  |  浏览/下载：30/0  |  提交时间：2013/03/25
In recent years  Fourier transform spectrometer (FTS) with small size and low mass is required in many applications with growing need for real-time and small platform spectral detection. In this paper  a micro Fourier transform infrared spectrometer (FTIR) based on spatial modulation mode was designed. This spectrometer has the advantages of high stability and simplified configuration. It also promises optical path differences (OPD) with high precision  as MOEMS technology is used in manufacturing the key components. The simulation and the experiments with regard to this FTIR configuration have been done. Firstly  the diffraction effect of the micro multi-step mirrors (MMSMs) is studied. We discuss the influence to the reversed spectrum by different mirror widths and different diffraction distances. Secondly  we simulate and analyze the influence of the source solid angle to the spectral resolution. Thirdly  we set up the theoretical model of the collimation error which is mainly from the defocus of the optical system and analyze the result caused by the collimation error. Fourthly  a new discrete Fourier transform arithmetic using least-squares cosines progression (LSCP) is proposed which can reconstruct the spectrum with nonuniform sampled signals. Finally  the MMSMs are fabricated used the MOEMS technology and the structural parameters are tested. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Design of stable image platform on airborne camera (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China
作者:  Yang L.;  Yang L.
收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25
Modulation transfer function resulting from random vibration was analyzed. To conclude that the effect of angular displacement was the major factor. Allowable MTF degradation was represented  and 34dB reduction was achieved at frequency of 100HZ. With the help of MSC.ADAMS simulation software  and convert allowable MTF degradation into stable system design parameters  simulated curve proves correct for isolator  which can guide perfect design for stabilization system. Based on the spatial mechanism and translational principle of parallelogram  and the irrotational displacement mechanism was tested by optical method  an irrotational displacement isolator was developed. It can meet the requirements of irrotational displacement and damp. An instance was given  coupled angle is less than 8?  it can satisfy the demand of aerial imaging. (2011) Trans Tech Publications.  
Study on the azimuth bearing scheme of a large Alt-azimuth telescope (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
作者:  Wang H.;  Dai S.;  Zhang J.;  Wang H.;  Zhang J.
收藏  |  浏览/下载：39/0  |  提交时间：2013/03/25
The azimuth bearing schemes in typical large Alt-azimuth telescopes  especially the 3.5-m APO telescope and the 4.1-m SOAR telescope were analyzed. A scheme of high-angular contacted thrust ball bearing integrated with a radial ball bearing was put forward. According to the Hertz contact theory  the corresponding parameters were designed for engineering application. The static performance parameters  within the range of 60 85 original contact angle were calculated. Compared with the traditional plane thrust ball bearing  the results shows that the high-angular (80) contact thrust ball bearing has more benefits at bearing strength and rigidity for large telescope. The 1500mm diameter prototyping bearing shows good performance  including the axial jitter is 0.009mm  the radial jitter is 0.006mm  the maximum starting torque without load is 30N·m  and the load capacity is more than 30t  which offers advanced technique path for the buildup of the high precision azimuth shafting and the whole telescope system. 2010 Copyright SPIE - The International Society for Optical Engineering.