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Broadband High-Reflection Dielectric PVD Coating with Low Stress and High Adhesion on PMMA 期刊论文
Coatings, 2019, 卷号: 9, 期号: 4, 页码: 9
作者:  Z.Z.Li;  Q.Li;  X.Q.Quan;  X.Zhang;  C.Song
收藏  |  浏览/下载：1/0  |  提交时间：2020/08/24
Structural design of large aperture rectangular mirror for space telescope (EI CONFERENCE) 会议论文
2nd International Conference on Civil Engineering and Transportation, ICCET 2012, October 27, 2012 - October 28, 2012, Guilin, China
Li Z.
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25
Structural design of large aperture mirror is one of the key technologies for space telescope development. To meet the requirements of high stiffness  strength and thermal dimensional stability  some factors such as support scheme  materials selection  lightweight design and flexible support design were taken into account. The three supports location of the mirror was determined according to the modal analytical solution. By adjusting the parameters of flexure hinge  influences of gravity  assembly stress and thermal stress on the mirror were reduced obviously. Finite element analysis (FEA) results indicate that the surface accuracy reach to rms10.2nm and 10.8nm under the gravity along optical axis direction and 5C uniform temperature rise respectively  the fundamental frequency of the mirror component is 268Hz. Dynamics test shows that the first order natural frequency is 256Hz  which shows an error less than 5% compared to FEA results. (2013) Trans Tech Publications  Switzerland.  
Effect of thickness on the structural, electrical and optical properties of ZnO films deposited by MBE (EI CONFERENCE) 会议论文
2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China
Yang X.; Su S.; Yi X.; Mei T.
收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25
A set of ZnO films of different thickness have been deposited on sapphire substrates using molecular beam epitaxy (MBE) by varying the growth time and the effect of film thickness on the structural  electrical and optical properties have been investigated. The X-ray diffraction (XRD) results indicate that the full width at half maximum (FWHM) of the (002) diffraction peak is decreased as the film thickness increasing  and the stress along c-axis is stable. Scanning electron microscope (SEM) measurement shows that the grains become more uniform as the film grows thicker and the film surface present distinct hexagon shape as the film is grown up to a thickness of 500nm. The optical absorbance  Hall mobility and photoluminescence (PL) intensity are increased in accordance with the thickness of the film. (2011) Trans Tech Publications  Switzerland.  
Thermal-structure analysis of supersonic dome based on three materials (EI CONFERENCE) 会议论文
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
Jiang Z.; Ai X.; Wei Q.; Liu B.; Jia H.
收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25
To a supersonic missile  a seeker could enhance the aerodynamic ability due to decrease the resistance in flying. At the same time  the primary function of a seeker has been considered as the most important equipment for a missile  due to the importance for cueing of targets and tracking for the final approach. However  the dome of a seeker  which is made up of glass  has poor mechanical performance. Especially  in the higher altitude  for a dome  in which the aerothermal and pressure loads could destroy the structure easily  it is necessary to do the thermal-structure coupled analysis due to varied materials. In the paper  to take the spherical dome of a seeker as a example  the analysis has been completed according to the varied materials consist of MgF2  Al2O3 and ZnS. The temperature loads and the pressure loads derived from the results of fluent analysis has been forced on the surface of dome  which simulates the actual Mach 2.5 in flying. According to the results of coupled analysis  the SEQV stress of the dome radium 80mm based on three materials had reached to 31MPa  which shows that the strength is sufficient for Mach 2.5  and offered the warranty to design the attaching to missile for the dome. At the same time  the results required the flexible mounting for the dome due to the displacements results  which the crystal material couldn't accept. 2011 IEEE.  
Nonlinear analysis method for predicting optical surface deformations resulted from assembly process (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
Dong W.; Yong Y.; Guang J.
收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25
There are three main nonlinear elements in the large mirror assemblies  which are screw pretension  adhesive stress and state changes in the assembly process. The optical shape will be influenced seriously by these factors. But the impacts will not be shown in linear analysis results  because as the simplification  these factors have been ignored. The nonlinear analysis method for predicting optical surface deformations resulted from assembly process is discussed in detail. Take a typical mirror support structure for example  the nonlinear analysis model was established. Comparing the calculation results with the optical shape test  it is illustrated that nonlinear analysis is more accurate and closer to the test result. And according to the simulation result  the bowl-shaped depression which was discovered in the test can also be explained reasonably. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Fabrication and testing 600mm diameter brazing SiC mirror (EI CONFERENCE) 会议论文
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, November 19, 2008 - November 21, 2008, Chengdu, China
Zhang B.-Z.; Wang X.; Wanf X. K.; Zhang Z.-Y.; Zhang X.-J.
收藏  |  浏览/下载：16/0  |  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 of the line-array fiber-optic image slicer based on silicon V-grooves (EI CONFERENCE) 会议论文
MEMS/MOEMS Technologies and Applications III, November 12, 2007 - November 14, 2007, Beijing, China
Liang J.; Guo P.; Liang Z.; Zhu Y.; Hou F.; Yao J.
收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25
Linear fiber-optic image slicer is used more and more in spatial exploration and imaging system. In this paper  a plane arranging method of fiber-optic array based on Si-V grooves is established in order to improve the accuracy and reduce the cost of manufacturing. Firstly  the Si-V groove array is micro-machined with anisotropic etching process  then optical fibers are placed in the grooves orderly with plane arranging method. Secondly  the end surfaces of the device are polished  also the linear fiber-optic image slicer is packaged. Finally  some parameters are tested  including structure parameters  transmittivity and vibration test. Experimental results indicate that the maximum error accumulated in 2000 periods of the Si-V grooves is 0.5 m  the error of the height in Si-V grooves is less than 0.15m  the roughness of the end surface is less than 0.9nm. The transmittivity of the linear fiber-optic image slicer that without optical film is 51.46% at the wavelength of 632.8nm. After random vibration experiment  the ratio of the broken fiber increased by 0.1%. While the temperature reached 320C  the stress of epoxy will be 130Mpa  which is close to the limit resistance stress of 139Mpa  some cracks appeared.  

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