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Figure error of optical elements induced aberrations of optical system 会议论文  OAI收割
Chengdu, China, 2021-06-14
作者:  
Pang, Zhihai;  He, Tianbin
  |  收藏  |  浏览/下载:18/0  |  提交时间:2022/03/10
Computation of misalignment and primary mirror astigmatism figure error of two-mirror telescopes 期刊论文  OAI收割
Journal of Astronomical Telescopes Instruments and Systems, 2018, 卷号: 4, 期号: 1, 页码: 10
作者:  
Gu, Z. Y.;  Wang, Y.;  Ju, G. H.;  Yan, C. X.
  |  收藏  |  浏览/下载:145/0  |  提交时间:2019/09/17
Design and test of pointing mirror assembly for spaceborne remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electronics, Communications and Control, ICECC 2011, September 9, 2011 - September 11, 2011, Ningbo, China
作者:  
Chen W.
收藏  |  浏览/下载:34/0  |  提交时间:2013/03/25
In order to ensure the surface figure of the pointing mirror (460mm long  290mm wide) in spaceborne remote sensing camera  Silicon Carbide was selected as the mirror material. The form of composite triangular and rectangular and the combination of open and closed back was explored in the lightweight design. A new kinematic mount and flexible structure in axis is used to hold the mirror around the lateral surface. The structure can minimize distortions induced by coefficient of thermal expansion mismatch among the materials. This eliminates the bending of the integral mount under the weight of the mirror. Optical performance of the mirror was analyzed under gravity load and temperature load using finite element method. Predicted surface figure error based on the removal of bias  tilt and power was calculated using an in-house Matlab script for mirrors. The pointing mirror assembly was tested using open loop servo control. And the surface figure was checked using interferometer. Surface figure accuracy is better than 1/30 ( 632.8nm  rms). The results show that the kinematic mount induces minimal figure error on the optical surface. 2011 IEEE.  
The Research of real time auto-recognition of the moire fringe (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Wang M.-J.; Wu Z.-G.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
Measuring the movement of raster by the method of moire fringe has the advantage of high sensitivity  high resolution and non-contacted measurement. The characteristic of moire fringe is that the image is white alternate with black  the angle of the stripes is uniform  the width of the stripes is uniform  the terminators of the stripes aren't clear. A fast method that can figure out the width and angle of the moire fringe precisely is put forward in this paper. It calculates the angle the stripes firstly. According to the principle of the minimum mean squared error (MMSE)  the closer a series of data is  the smaller the value of the MMSE will be. The method is described as follows: It takes the image's center as the origin  180 beelines pass through the origin with the same angle interval. it calculates the value of the minimum mean squared error of the 180 beelines and find out the least one among those  then the angle of the moire fringe comes out primarily. In order to improving the calculating precision of moire fringe  60 equal angles are divided in the neighborhood of the angle  then a precise angle of moire fringe is calculated according to the principle of the MMSE. After getting out the angle of the moire fringe  we begin to calculate the width of moire fringe. A line vertical with the moire fringe is drawn  and we can get the width of the moire fringe by the vertical line. In order to get over the influence of the noise  an effective area with the shape of diamond is selected in the image. The data of area is accumulated and projected according to the direction of moire fringe  and a sine curve come out. The width of moire fringe can be obtained by getting the position of the first wave crest  the position of the last wave crest and the number of wave crest. Experiments prove that the precision of the method put forward in this paper is enhanced in comparison with the traditional frequency method  the precision of width calculation achieves to 99.6% according to the evaluation indicators of width detection error. The computing speed is boosted largely compared with traditional method  and it can achieve with 15 ms  that satisfying the demand of real time. 2011 SPIE.  
Brazing RB-SiC used in large aperture space optical system (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Materials and Products Manufacturing Technology, ICMPMT 2011, October 28, 2011 - October 30, 2011, Chengdu, China
Zhang B.; Zhang Z.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
Because of the sic material's superior optical characteristic  machine characteristic and hot characteristic  it becomes currently the space big aperture reflector choose firstly1. For larger aperture sic mirror  it is not economical and safe to make the monolithic body directly 2  3. The SiC mirror brazed assembly with several segments can solve these problems. In this paper  one 600 mm sic plane mirror as demonstration welded with 3 radial segments is roughly grinded to the required figure at first  then the mirror is finely grinded and polished by the technology of CCOS  the mirror figure error is less than 1/20 ( = 632.8nm) in RMS finally. The problems of the preferential removal near braze joint are solved. The methods of reducing the residual stress of mirror are discussed. At last  some measurements and experiments are carried on  and the results conclude that the brazed SiC mirror can meet the requirement of large aperture optical systems. (2011) Trans Tech Publications.  
An improved, real-time method for removing the cyclic error of a homodyne interferometer 会议论文  OAI收割
international symposium on photoelectronic detection and imaging 2012: laser sensing and imaging; and biological and medical applications of photonics sensing and imaging, beijing, china, may 24, 2011 - may 26, 2017
ZhaoSuwen; WenDesheng; ZhuShaolan; LiangShitong
收藏  |  浏览/下载:31/0  |  提交时间:2012/07/09
Fabrication and testing 600mm diameter brazing SiC mirror (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Wang X.;  Zhang X.-J.;  Zhang Z.-Y.;  Zhang Z.-Y.;  Wang X.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
SiC is a preferential material for space large aperture mirror at present. Aperture of 1 meter sic mirror can meet most requirements of space optical systems. For larger aperture sic mirror  it is not economical and safe to make the monolithic body directly. The SiC mirror brazed assembly with several segments can solve these problems. In this paper  one 600 mm sic plane mirror as demonstration welded with 3 radial segments is roughly grinded to the required figure at first  then the mirror is finely grinded and polished by CCOS technology  the RMS of the figure error is less than 1/20 ( = 632.8nm) finally. The problems of the preferential removal near braze joint and material removing rate influenced by deformation of mirror surface are solved. Methods of reducing the residual stress of mirror are discussed. At last  some measurements and experiments are carried on  and the results conclude that the brazed SiC mirror can meet the requirement of large aperture optical systems. 2009 SPIE.  
Manufacturing and Testing SiC Aspherical mirrors in Space telescopes (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Fan D.;  Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
Reaction Bonded (RB) SiC mirrors due to their excellent specific stiffness and thermal properties have been widely used in space telescopes. However  polishing large SiC aspherical mirrors is difficult compared to other materials such as fused silica or Zerodu. In addition  surface roughness of the polished SiC mirrors is limited by the defects of the materials and needs to be improved by means of surface coating technique. This paper introduces the current progress of large SiC aspherical mirrors manufacturing and testing in CIOMP. In particular  the procedures of making large off-axis aspherical mirrors were discussed in detail. A proprietary computer controlled optical surfacing (CCOS) technique was utilized to grind and polish the mirrors and the computer aided null test was used to measure the surface figure. As results  a 600mm class off-axis SiC aspherical mirrors was demonstrated with figure error less than 13nm rms.  
Studies of Trail and Error Method for Cyrstal Structural Determinations (III) Application and Program System of SYSTEM 90 期刊论文  OAI收割
ACTA PHYSICO-CHIMICA SINICA, 1994, 卷号: 10, 期号: 12, 页码: 1087-1092
作者:  
Hou Yonggeng;  Gao Min;  Li Lipu;  Ma Zhimei
  |  收藏  |  浏览/下载:13/0  |  提交时间:2019/04/09