一种简单实用的兆瓦级脉冲激光发散角测试方法

A Simple and Practical Method for Measuring the Divergence Angle of Megawatt-Level Pulsed Lasers

摘要: 针对工程应用领域对兆瓦级脉冲激光发散角快速调试、测试及验收的需求，本文提出了一种兆瓦级脉冲激光发散角测试方法——打靶法，并将打靶法得到的测试结果与目前广泛使用的套孔法进行了对比。相比于套孔法，打靶法能够通过望远镜看到聚焦透镜焦平面处靶纸上记录的激光光斑分布，并根据望远镜的内部刻度读出激光发散角，不受光束质量、能量计以及光阑定位精度等因素的影响，为工程应用领域兆瓦级脉冲激光的发散角测试提供了新的选择。

Abstract: To meet the demands of rapid adjustment, testing, and acceptance of megawatt-level pulsed laser divergence angles in engineering applications, this paper proposes a testing method—the Far-Field Target Method—and compares its results with the widely used Aperture Diaphragm Method. Unlike the Aperture Diaphragm Method, the Far-Field Target Method allows the observation of the laser spot distribution on the target paper at the focal plane of the focusing lens through a telescope. The divergence angle can then be directly read from the telescope’s internal scale, eliminating influences from beam quality, energy meter accuracy, and aperture positioning precision. This approach provides a new solution for measuring the divergence angle of megawatt-level pulsed lasers in engineering applications.