提出了一种基于权重分组的可见光波段光学系统的无热化设计方法。基于常温下满足像质要求的光学系统,计算了每一片透镜产生色差及热差能力的综合权重,通过比较权重进行结构分组,将初始系统等效成两个单透镜系统以进行光学材料的挑选。对焦距为400 mm、F数为4的双高斯型航空相机在-40~+60 ℃的温度范围内进行了无热化设计。在各个温度下,该系统在空间频率为55 lp/mm处的调制传递函数值均大于0.4。研究结果表明,该方法能使长焦光学系统在大温差环境下保持较好像质,光学性能稳定。

An athermalization design method of a visible light optical system is proposed based on the grouping by weight. For this optical system satisfying the requirements of image quality at normal temperature, the comprehensive weight of chromatic power and thermal power produced by each element is calculated. The structures are grouped by the comparison among the comprehensive weights, and the initial system is equivalent to two single lens systems for the choice of the optical materials. The athermalization design of a double Gaussian aerial camera with a focal length of 400 mm and an F number of 4 is conducted, whose modulation transfer function (MTF) is larger than 0.4 at a spatial frequency of 55 lp·mm -1 under the temperature in the range of -40-+60 ℃. The research results show that this design method can ensure the telephoto optical system possess good image quality and stable optical performance under the environment of large temperature difference.