用于导弹逼近告警的“日盲”紫外光学系统设计

紫外告警技术在军事应用中扮演着重要的角色。基于日盲紫外光学系统的最佳工作波段240~280 nm，设计了一款用于导弹逼近告警的光学系统。为提高系统接收的紫外辐射能、扩展系统探测范围以及简化系统结构，系统中采用了非球面和二元衍射光学元件。系统中含有5 片透镜，其焦距为50 mm，视场角为43。探测器采用ANDOR 公司的iKon-L 936 型CCD，其像元大小为13.5 m13.5 m，有效成像面积为27.6 mm27.6 mm。系统优化后，最大RMS 半径仅为11 m 左右，远小于像元尺寸。超过86%来自物方各视场的紫外辐射会聚在半径为6.75m 的圆内。像质表明，所设计的系统能够满足日盲紫外光学系统的工作条件。若减小焦距，则系统的视场角可进一步增大。

Design of solar-blind UV optical system for missile approach warning

Ultraviolet (UV) warning technology is playing a very important roll in the field of military application. Based on the optimal working waveband of solar-blind UV optical system from 240 nm to 280 nm, an optical system was designed for missile approach warning. To enhance the received light energy, expand the detection range and simplify the system structure, aspheric surfaces and binary elements were adopted in the system. Only five elements were used to realize the focal length 50 mm and field of view (FOV) 43 degrees. iKon-L 936 from ANDOR company was selected as the UV detector, which has pixel size 13.5 m13.5 m and active image area 27.6 mm27.6 mm. After optimization, the maximum RMS radius is only about 11 microns, which is much less than pixel size of the detector and more than 86% of the light energy from each FOV is converged within the circle of radius 6.75 microns. The image quality shows the designed system can meet the working requirements of solar-blind UV optical system. If the focal length can be decreased, the FOV of the system can be enlarged further.