摘要
高分辨率空间红外相机的光学系统具有大口径和大相对孔径的特点,针对某高分辨率红外相机的设计需求,根据三级像差理论计算了同轴三反系统初始结构,设计了传统的同轴三反和同轴偏视场三反系统。通过同轴两反主光学系统和离轴三反后光学系统合理的光焦度分配,设计了组合式五反系统共三种光学系统。设计的系统工作波长8~10μm,焦距7 000mm,相对孔径1…2.29,线视场角±0.58°×0.03°。在综合分析成像性能和光学加工、检测及系统装调等技术的基础上选定组合式五反光学系统为最终方案。五反光路结构尺寸为3 500mm×3 050mm×3 050mm,主镜达到3m级别,考虑到单镜整体加工检验难度,采用18块边长750 mm的正六边形子镜进行合成孔径拼接,子孔径拼接后系统全视场内的调制传递函数大于0.4,系统各项性能满足了技术指标。
The optical system of the high-resolution spatial infrared camera has the characteristics of large aperture and large relative aperture.In this paper,according to the design requirement of a high-resolution infrared camera,the initial structure of the coaxial three-mirror system is calculated according to the third-order aberration theory.The traditional coaxial three-mirror and coaxial partial eccentric-field three-mirror systems are designed.A total three kinds of optical systems of combined five-mirror system are designed by the reasonable power distribution of the coaxial two-mirror optical system and the off-axis three-mirror optical system.The designed working wavelength is 8-10μm,focal length is 7 000 mm,relative aperture is 1\:2.29,and angle of line field is±0.58°×0.03°.After a comprehensive consideration of the optical system ability of imaging,technology of optical processing,testing and system alignment,the combined five-mirror optical system is selected as the ultimate solution.The size of five-mirror optical path structure is 3 500 mm×3 050 mm×3 050 mm.And the aperture of primary mirror reaches 3 m level.Taking into account the difficulty of single-lens processing inspection,18 regular hexagonal mirrors are used to splice synthetic aperture.The modulation transfer function in the whole field of the system after the subaperture splicing is greater than 0.4,and the system performance meets technical index.
作者
罗秦
钮新华
张冬冬
LUO Qin;NIU Xinhua;ZHANG Dongdong(University of Chinese Academy of Sciences,Beijing 100049,China;Key Laboratory of Infrared Detection and Imaging Technology,Chinese Academy of Sciences, Shanghai 200083,China)
出处
《上海航天》
CSCD
2018年第1期97-103,共7页
Aerospace Shanghai
关键词
光学设计
同轴三反系统
五反系统
合成孔径
红外相机
系统方案
大口径
optical design
coaxial three-mirror system
five-mirror system
synthetic aperture
infrared camera
system solutions
large aperture
