高功率激光系统鬼点空间坐标的快速定位算法

A Quick Algorithm for Locating Ghost Coordinates in High-Power Laser Systems

提出了一种高功率激光系统中鬼点空间坐标的快速定位算法,用于在设计阶段分析系统中的多次反射与多级衍射鬼点,以避免对系统造成危害。算法采用二叉树表示的多叉树存储鬼光束数据,同时追迹第一近轴光线和实际主光线,依据第一近轴光线确定鬼点的z坐标zg,将实际主光线与z=zg平面的交点作为实际鬼点位置。以倾斜透镜和含衍射元件的终端光学系统(FOA)为例预测了鬼点的空间坐标,经高密度实际光线追迹法验证,在所得鬼点平面相应位置确有光能聚集,表明鬼点空间坐标与实际鬼光束的密集区域相符。使用该方法在16 s内定位了含222面的激光系统的13124个鬼点。

A quick algorithm for locating the ghost coordinates in high-power laser systems is presented for analyzing multi-reflection and multi-order diffraction ghosts in design so as to avoid damaging the systems.The primary paraxial ray and chief ray are traced and saved in a multi-pork tree expressed as a binary tree at the same time,the z coordianate zg of each ghost is determined by tracing the primary paraxial ray,and the intersection point of the chief ray and the plane z=zg is regarded as the position of the real ghost.Taking a tilt lens and the final optical assembly（FOA） with a diffraction optical component as examples,the space coordinates of some ghosts are predicted.Certified by high-density real ray tracing,optical energy is focused at the predictive position in corresponding ghost plane.The results show that the predicted ghost point is coincident with the area at which the real rays condense.The positions of 13124 ghosts in a laser system including 222 surfaces are found in 16 s using this algorithm.