摘要
针对基于硅基液晶(LCOS)拼接技术的动态星模拟器对比度低,无法在星图识别过程中为星敏感器提供全部有效目标的问题,提出通过抑制光学系统杂散光来提高LCOS拼接动态星模拟器对比度的方法,讨论了偏振度对于杂散光的影响,并推导出入射角与偏振度的函数关系。设计了抑制杂散光的光学系统,该系统包括利用复合抛物面聚光器(CPC)结合望远系统组成照明光源,配合多棱镜的1/4波片和视场角不小于11°的准直光学系统。在截止频率为60lp/mm,视场角小于±5°的情况下,该准直系统的调制传递函数(MTF)大于0.7。实验显示:该高对比度LCOS拼接动态星模拟器的星间角距误差小于18″,相对于传统型的星模拟器杂散光降低了2.38倍,其在保证精度的条件下,降低了动态星模拟器的背景噪声,提高了动态星图的可识别率,基本可以满足星敏感器在多星等条件下的对精度和动态特性的需求。
The dynamic star simulator based on Liquid Crystal on Silicon LCOS splicing technology has Low contrast, and it can not provide all effective targets for the star sensor in star map recognition. Thus a method for improving the contrast of the dynamic star simulator by suppressing stray lights was put forwarded. The influence of the polarization degree on stray light was discussed in detail, and the function of the polarization degree and the angle of incidence was derived .The optical system for stray light suppression was designed, including a lighting source designed by combination of a Compound Parabolic Concentrator（CPC） and a telescopic system, a 1/4 wave plate with combination of multi-prisms, and a collimating system with field angle greater than 11°. The MTF of the collimating system is greater than 0.7 when the edge frequency is 60 lp/mm and the field angle is less than ：k5°. The experiments show that the angle distance error between stars of the high contrast dynamic star simulator based on LCOS splicing is less than 18, and its stray light energy is reduced by 2.38 times as compared with those of conventional star simulators. These results indicate that the high contrast dynamic star simulator based on LCOS splicing can not only reduce the background noise of dynamic star simulator effectively, but also canimprove the recognition rate of star map. Consequently, it meets the requirements of dynamic star simulator in all magnitude levels for high dynamic characteristics and high precisions.
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2016年第3期511-520,共10页
Optics and Precision Engineering
基金
国家863高技术研究发展计划资助项目(No.2008AA12A203)
关键词
光学系统设计
硅基液晶(LCOS)拼接技术
星模拟器
杂散光
偏振度
星图识别
optical system design
Liquid Crystal on Silicon （LCOS） splicing technology
star simulator
straylight
polarization degree
star map recognition
