三反射主动变焦系统设计  

Design of the active zoom system with three-mirror

作　　者：沈本兰[1] 常军[1] 王希[1] 牛亚军[1] 冯树龙[2] 

机构地区：[1]北京理工大学光电学院,北京100081 [2]中国科学院长春光学精密机械与物理研究所,长春130022

出　　处：《物理学报》2014年第14期160-166,共7页Acta Physica Sinica

基　　金：教育部新世纪优秀人才支持计划(批准号:2012cx01017);北京理工大学科技创新计划重大项目培育专项计划(批准号:22050205)资助的课题~~

摘　　要：空间光学系统在对深空探测、监视、威胁侦测和对地高分辨率侦查等应用中,不仅需要能同时获得高分辨率和宽视场范围的变焦系统,还需要体积小、重量轻、低能耗及快速调焦的系统,传统机械变焦系统因需要复杂精确的机械运动控制而存在诸多问题.因而,基于主动光学理论,将主动光学元件应用到成像系统中,提出了通过某个或某几个光学元件的曲率半径变化实现系统焦距变化的理论.根据初级像差理论和系统的外形尺寸,研究了系统主动变焦原理,确定了初级像差方程组的约束条件,求解共轴主动变焦系统的初始结构参数,借助ZEMAX软件进行优化设计,设计了一个由静止的主镜、曲率半径作为变量的次镜和三镜、无光焦度的平面镜组成的三反射主动变焦系统.由于该共轴三反射主动变焦系统存在两次遮光,会影响系统像面能量的接收,因此,指出对共轴系统进行无遮拦离轴优化设计的必要性,讨论了离轴系统设计理论,并设计了离轴三反射主动变焦系统.In the applications of deep-space exploration, surveillance, threat detection and high resolution investigation on the ground, space optical systems need not only both the high resolution and width of view zoom system, but also the small size, light weight, low power and fast focusing system. As the traditional mechanical zoom system requires complex and precision mechanical motion, many problems are usually caused. Thus, based on active optics, the active optical elements are applied to the imaging system, and it is proposed that the optical element curvature radius should be variable to realize the transition among the different focal lengths. According to third-order aberration theory and dimension calculation of optical system requirement, the active zoom theory is studied, and the third-order aberration equation constraints are confirmed. Then the initial construction parameters of coaxial active zoom system are achieved by solving the equations. The system is optimized with using the optical design software ZEMAX. The system consists of the static primary mirror, the secondary and third mirror with the variable curvature radius, and the plane mirror with zero-power. As two times the light is obscured by the elements in the coaxial active zoom system, the amount of the energy on the image plane will be affected. For this reason, it is proposed that the unobstructed off-axis optimization should be necessary to the coaxial system. The off-axis system design theory is studied and the off-axis active zoom system is designed.

关 键 词：主动变焦 初级像差 三反射镜 光学设计 

分 类 号：O435.1[机械工程—光学工程]