为提高数字高速多幅相机的像面照度,简化光学系统结构,提出一种离轴光学系统设计方法.该系统使用多组相同物镜,采用圆心一组,圆周均匀分布多组的方式平行阵列排布.分布于圆周上的物镜,其像面接收器相对物镜轴心平移离轴,以获得与圆心物镜相同的物面图像.分析了单物镜像面照度、畸变等与视场有关参数对光学系统各像面匹配的影响.在此基础上给出一个5通道离轴光学系统设计实例,系统空间分辨率优于30 lp/mm,畸变小于0.1%,F数2.0.相比目前广泛采用的棱锥、棱镜分幅方式,该离轴光学系统像面照度增加5倍以上,系统结构简易.

In order to improve the illuminance of image plane and simplify the structure of digital high-speed multi-frame gated camera,an off-axis optical system was proposed.The system uses several same lenses,one of them lies in the center of circle and the others are equally distributed on the circumference.In order to obtain the same image with the center lens,receivers of the lens that are distributed on the circumference parallel move away from the axis of its lens.The illumination,distortion and other aberration related with field of view,were analyzed.Based on the above analyses,a five-channel off-axis optical system was given.The spatial resolution of the system is better than 30 lp/mm ,distortion is less than 0.1%.and F number of the lens is 2.0.Compared with mostly used prism or pyramid to split light beams,the illumination of the new system increases more than 5 times and the structure is more simple.