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Structural optimization design and analysis of a 2m space-based mirror 会议论文  OAI收割
Xi'an, China, 2023-03-03
作者:  
Wang, Sheng;  Wang, Wei;  Hu, Bin;  Wei, DeJing;  Lin, ShangMin
  |  收藏  |  浏览/下载:26/0  |  提交时间:2023/10/09
Large diameter optics support optimization based on finite element method and optical surface fitting with zernike method 会议论文  OAI收割
Shanghai, China, 2020-06-29
作者:  
Liang-Xiao, Zhao;  Jian, Zhang;  San-Feng, Hao;  Li-Min, Gao
  |  收藏  |  浏览/下载:30/0  |  提交时间:2021/03/04
Application of interferometry measurement in large-scale optic-electrical theodolite (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Sensors, Measurement and Intelligent Materials, ICSMIM 2012, December 26, 2012 - December 27, 2012, Guilin, China
作者:  
Sun Z.
收藏  |  浏览/下载:45/0  |  提交时间:2013/03/25
Interferometry is a very important method in high accuracy measurement for optical system. This article briefly introduced the conception of interferometry and took a product of 4D Technology as an example to carry on the measurement. A large-scale optic-electrical Theodolite in assemblage was measured  and its primary mirror was 400mm in diameter. With the analysis of the results  some micro adjustments of the mechanical structure proceed  and it made the system perform better. The final results of the whole system is 1.061 in P-V value and 0.1136 in RMS value (=632.8nm)  this meets the demand of optical design and practical application. The result demonstrates that interferometry is a good way to be utilized and optimize in the procedure of assemble. (2013) Trans Tech Publications  Switzerland.  
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:66/0  |  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.  
Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文  OAI收割
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
作者:  
Zhang L.;  Zhang L.
收藏  |  浏览/下载:68/0  |  提交时间:2013/03/25
The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope  the structure should have high stiffness and high reliability and light weight. Compared with invar  aluminum alloy and titanium alloy  carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper  optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm  total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages  such as ultra-light weight  high stiffness and dimensional stability  etc. The optimization method and the baffle design can be helpful to other coaxial telescopes  such as Cassegrain  Gregorian and their subdivisions. 2012 IEEE.  
Nanoscale patterns made by using a 13.5-nm Schwarzschild objective and a laser produced plasma source (EI CONFERENCE) 会议论文  OAI收割
Optical Micro- and Nanometrology IV, April 16, 2012 - April 18, 2012, Brussels, Belgium
作者:  
Wang X.;  Wang X.;  Wang X.;  Wang Z.;  Wang Z.
收藏  |  浏览/下载:41/0  |  提交时间:2013/03/25
Lithium fluoride (LiF) crystal is a very promising candidate as nanometer resolution EUV and soft X-ray detector. Compared with other EUV and soft X-ray detectors  charge coupled device and photographic films  LiF crystal has high resolution  large field of view and wide dynamic range. In this paper  using LiF crystal as EUV detector and a Schwarzschild objective (SO) working at 13.5nm as projection optics  mesh images with 4.2 m  1.2 m and 800 nm line width and pinhole patterns with 1.5m diameter are acquired in projection imaging mode and direct writing mode  respectively. Fluorescence intensity profiles of images show that the resolution of mesh image is 900 nm  and the one of pinhole image is 800 nm. In the experiments  a spherical condense mirror based on normal incidence type is used to eliminate the damage and contamination on the masks (mesh and pinhole) caused by the laser plasma  and the energy density is not decreased compared with that the masks are close to the plasma. The development of the SO  the alignment of the objective and the imaging experiments are also reported. 2012 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Optimization and design of the bottom support of the primary mirror chamber in the opto-electronic device (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Transportation, Mechanical, and Electrical Engineering, TMEE 2011, December 16, 2011 - December 18, 2011, Changchun, China
作者:  
Zhang G.;  Zhang G.;  Zhang G.
收藏  |  浏览/下载:14/0  |  提交时间:2013/03/25
In the large-diameter opto-electronic device tracking equipment  by full analyzing the support structure of the primary mirror  the primary mirror usually uses the combination of the bottom support and the lateral support. Because both the bottom support and the lateral support are installed on the primary mirror chamber's base plate  after changing the welded structure of the primary mirror chamber structure to the cast structure and improving the stiffness of the primary mirror base plate  the stiffness of the base plate will show in the amount of sloshing of the primary mirror relative to the primary mirror chamber and therefore influences the tracking accuracy of the opto-electronic device. During the assembling and adjusting of the primary mirror in the actual process of working on the project  the amount of sloshing of the primary mirror is reduced significantly. The results show that in working on the primary mirror support  as is found that the amount of sloshing of the primary mirror relative to the primary mirror chamber is comparatively large  the forms and structure stiffness of bottom support and lateral support should be considered  together with that the stiffness of the primary mirror chamber acting as the basis is playing the crucial role. 2011 IEEE.  
Research on automatic Hartmann test of membrane mirror (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Zhang P.
收藏  |  浏览/下载:38/0  |  提交时间:2013/03/25
Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements  so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror  the surface configuration must be tested. However  membrane mirror's shape is always changed by variable voltages on the electrodes  and the optical properties of membrane materials using in our experiment are poor  so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem  an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source  CCD camera  splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer  and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured  and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results  Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Fabrication technique of large-scale lightweight SiC space mirror (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Zhang G.;  Zhang G.;  Zhang G.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion  high stiffness  high optical quality  and its dimensional stability are better than other traditional optical substrate materials such as ULE  Zerodure  Beryllium (Be) and so on. In this paper  the lightweight silicon carbide space mirror blank was fabricated by reaction sintering. As a space born mirror material  silicon carbide must be an optical grade ceramic. So we prepared the silicon carbide green body with gel-casting method. Then some carbon materials were supplemented into the green body which will bring reaction-sintering with silicon in a vacuum furnace during 1500-1600C  ultimately the reaction bonded silicon carbide was made. The diameter of SiC space mirror blank we have made is 680mm. If expanding the size of the vacuum furnace  bigger mirror blank can be obtained. The test results show that the mechanical and thermal properties of RB-SiC are excellent with bending strength of 350MPa  fracture toughness of 4.1 MPa·m1/2 and coefficient of thermal expansion(CET) of 2.6710-6/K. The surface roughness(RMS) could be better than 3nm.  
Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China
Yang W.; Jingxu Z.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
Large-aperture telescope can be used in surveying battlefield  researching landform  searching object  real-time monitoring  imaging  detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object  quantity  geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology  people require larger aperture in optics-electronic (OE) system. By increasing optical aperture  the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture  the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors  such as deadweight  deformation of heat  environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror  precision of the system is ensured. During the designing phase  one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope  the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture  small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope  the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing  then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high  precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper  various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply  which was operated by the Directed Energy Directorate of the Air Force Research Laboratory  Kirtland AFB  NM  USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.