大变倍比中波红外变焦系统的小型化设计

基于中波红外320240制冷型探测器，采用机械正组补偿方式，引入衍射光学元件（DOE），并采用折叠光路，实现大变倍比中波红外变焦光学系统的小型化设计。利用变焦原理和Zemax光学设计软件给出系统结构参数,并对设计结果进行像质评价，对凸轮曲线求解等。设计与分析结果表明:系统使用6片透镜在3.7 m~4.8 m波段实现了18 mm~360 mm连续变焦，满足100 %冷光阑匹配，在空间频率16 lp/mm处MTF值均大于0.5。该系统具有大变倍比、变焦轨迹平滑等特点，可应用于机载光电侦察设备中。

Miniaturization design of large zoom ratio MWIR zoom optical system

Based on mid-wave infrared (MWIR) (320×240) cooled detector, an infrared miniaturization and continuous zoom optical system adopting mechanical compensation method, employing diffractive optical element and folded beam path was designed. Using zoom system principle and Zemax optical design software, the optical design parameters were offered, image quality evaluation was presented and cam curve was solved. The design results show that six lenses are used in system, continuous zoom of 18 mm ~ 360 mm is achieved at band of 3.7 μm~4.8 μm, and cold optical stop matching is 100%. The value of modulation transfer function is all above 0.5 at the spatial frequency of 16 lp/mm. The system is characterized by large zoom ratio, excellent images, miniaturization and smooth zoom locus. It can be used for airborne electro-optical detection equipments.