为了完成飞行器导引头目标识别与探测任务，以短焦距、大视场进行搜索并确认目标，以长焦距、小视场进行高精度目标识别。通过选择正组补偿的机械补偿法，采用3种普通光学材料，在长焦距位置，将前固定组、变倍组的组合设计为远摄型，使得系统结构紧凑，满足导引头小型化的要求。利用CODE V光学设计软件，优化设计了焦距为30~150 mm，视场角为1290°×1025°~259°×207°，筒长仅为174 mm的变焦距光学系统，得到成像质量优良的设计结果。各焦距、全视场平均传递函数值在50 lp/mm时为0695，测试结果为0562，满足系统的性能要求。

In order to complete recognition and detection tasks of the aircraft seeker, a high precision, miniaturization of the zoom optical system is designed. Targets are searched and identified at short focal length, wide field, and recognized at long focal length, narrow field. The mechanical compensation method is selected using three kinds of common optical materials. At the location of the long focal length, combinatorial design of the front group and the zoom group can make the system compact, and meet seeker miniaturization requirements. The zoom optical system with optimization focal length about 1290°×1025°~259°×207° and lene tube length only 174 mm is designed by using the CODEⅤ optical design software. For the each focal length and each field of view, the average MTF is 0695, and tested result is 0562 at 50 lp/mm, which can meet performance requirements of the system.