大视场大相对孔径双波段夜视R-C系统设计

Dual band night vision R-C system with wide field of view and large relative aperture

为了利用可见光波段和长波红外波段所蕴含的不同信息进行数据融合和实时彩色显示,设计了一种大视场的单通道双光谱R-C结构。双谱光学系统的具体结构为R-C系统加校正镜,采用主镜后分光,利用二向分光镜反射可见光波段,透射长波红外波段。全视场角和相对孔径分别为5°和1∶1.7;次镜遮拦比为1∶3;光学系统在可见光波段MTF=0.60的成像质量对应的空间频率为50 lp/mm,在长波红外波段MTF=0.30的成像质量对应的空间频率为15 lp/mm。对该系统的结构特点进行分析和讨论,给出了各种像差曲线和光学传递函数。

Low-level-light color night vision systems are developing from the single band to the multi-band,and information from visible band and long wave infrared（LWIR） band is used to generate fused image and color vision.A dual-band optical system is developed,which made of Ritchie-Crétien（R-C） system,correcting lens,and the beam-splitter which reflects in visible region and transmits in the long wave infrared（LWIR） region.Its full field of view and relative aperture are 50 and F/1.7 respectively,the ratio of scondary mirror＇s central obstruction is 1∶3,and MTF is higher than 0.60 at 50 lp/mm in the visible region,higher than 0.30 at 18 lp/mm in the LWIR region.The features of the lens are discussed.The aberration curves and MTF curves of the system are presented.