基于鬼像和像差分析的高功率激光装置透镜设计

Lens Design Based on Ghost Image and Aberration Analysis in High-Power Laser Facility

为了设计能够满足高功率固体激光装置需求的空间滤波器透镜,采用矩阵光学方法,分析光束经过单透镜传输时剩余反射形成各阶鬼像的过程,得到鬼像位置与透镜曲率半径的关系式。该关系式表明,透镜的曲率半径设计可以控制鬼像所在的区域。根据高功率激光装置光路排布的特点简化鬼像分析,利用自行开发的鬼像追迹软件分析了主放大级鬼像分布特点。通过改变透镜的曲率半径和倾斜透镜这两种方式,基于鬼像规避和像差最小化两种原则,最终确定主放大级透镜曲率半径的最优选择为1∶3弯月型,凸面朝向光学元件集中的方向。该方法可普遍应用于指导高通量复杂光学系统的透镜设计。

By the method of matrix optics, the formation process of ghost images from the residual reflection when beam passes through a single lens is analyzed and the relation between the localities of the ghost images and the curvature radius of the lens is achieved. From the relation, the localities of the ghost images can be determined by designing the curvature radius of the lens. The ghost images analysis is simplified considering the distribution characteristics of the beam path in high-power laser facility, based on which the distribution of the ghost images in the main amplification section is analyzed by the special software. By changing the curvature radius or tilting the lens, with the principles of avoiding the ghost images and minimizing the aberration, the curvature radius of the lens used in the main amplification section is selected as 1：3 with a shape of crescent and convexity in the direction of more concentrated optics. The method proposed can also be applied to the lens design in high-flux complicated optics system.