半球空域长波红外成像光学系统设计

Design of Hemisphere Airspace LWIR Imaging Optical System

介绍了一种半球空域成像长波红外光学系统的设计。该光学系统采用二次成像结构,有效的压缩了光学系统的径向尺寸。由于该光学系统视场较大,因此采用了F-θ的"非相似"成像方式。利用ZEMAX软件进行了优化设计,合理解决了像面照度均匀性和大视场轴外像差的问题。同时对该光学系统进行了分析评价并给出光学系统的传递函数曲线、点列图等设计结果。该光学系统仅使用六片光学元件,采用两个非球面,全视场角和相对孔径分别为184°和1/1.93,全视场内的传递函数值在20lp/mm处达到0.45以上,像质优良。光学系统总长为71 mm,最大直径30 mm,光学元件质量仅为45 g,光学系统体积小、质量轻,可适用于多种平台。

A hemisphere long wavelength infrared（LWIR） imaging optical system design is introduced. Thesecondary imaging structure is adopted in the system to compress the radial size of the system effectively. For widerfield of view of the system, F-θ dissimilarity imaging mode is adopted. Optimization design is carried by using ZE-MAX software, so the problems such as image illumination uniformity and wide field of view off-axis aberration aresolved. At the same time the system is analyzed and evaluated and design results such as transfer function curvesand spot diagram are presented. Only 6 pieces of optical components and 2 pieces of aspheric surface are used inthe system. The full field of view and relative aperture is 184° and 1/1.93 respectively, the transfer function value infull field of view is more than 0.45 at 20 lp/mm, and good image quality is got. The total length and the longest diam-eter of the system are 71 mm and 30 mm respectively, the weight of the optical components is only 45 g. The opticalsystem has small volume and light weight, which is suitable for a variety of platforms.