可见光、红外一体化两用相机的光学设计

Optical design of visible/infrared integrative camera

主要介绍可见光与红外一体化两用相机的光学系统设计。可见光、红外波段公用口径为1 m的主镜,可见光波段450～900 nm,采用折轴三反系统,焦距f1=12.0 m,视场1.5°×0.5°,选用TDICCD;红外波段范围8～12μm,采用主聚焦系统,由主镜和3片锗镜组成,焦距f2=2.0 m,视场2w=2.0°,采用红外非制冷探测器。主聚焦系统的校正镜组在次镜后方一定的距离,次镜固定件可以旋转180°。旋入次镜时,光线由主镜反射进入次镜,再依次经折轴镜与三镜反射到达可见光TDICCD,实现可见光成像;旋出次镜时,光线由主镜反射进入红外校正镜组到达红外非制冷探测器,实现红外成像。系统正是通过这种次镜的旋入旋出来实现双波段光学系统的切换。该系统将可见光与红外系统整合在一起,减小了系统的重量和体积,可使其在运行轨道上实现一星两用。

The optical system design of the visible/infrared integrative camera was introduced. In the system, the primary mirror was used for two wave bands together whose aperture was 1 m. In the visible band of 450-900 nm, the coaxial three-mirror-anastigmat system was chosen with focal length of 12.0 m and field of view of 1.5°×0.5°, and TDICCD was used. In the infrared band of 8-12 μm, the prime focus system was chosen with focal length of 2.0 m and field of view of 2.0°, which was composed of the primary mirror and three Ge lenses, and uncooled infrared detector was used. The first lens of the prime focus system was set behind the secondary mirror, the retainer of which can circumrotate 180°. When the secondary mirror was switched into the system, the visible camera was working, and when the secondary mirror was switched out of the system, the infrared camera was working. The optical system combines the two wave bands cameras together, which reduces the quality and volume of the camera, and realize the double uses of one star in its orbit.