一种大功率宽波段激光束散角的校准测试方法

在大功率激光系统的评价与分析中，激光器的光束品质是系统光束品质的决定性因素，也是激光器验收、鉴定的重要指标，其中束散角是判别激光光束质量的重要参数。本系统测试激光波长的范围比较宽，一般在0.532μm～10.6μm之间，没有合适的探测器能够覆盖整个波段，所以采用了一种新的方法来解决宽波段束散角的测量问题。选用CCD成像和扫描狭缝相结合的方法来实现宽波段激光光束束散角的测量，可见光和近红外波段（0.532μm～1.2μm）激光光束采用CCD法测量激光束散角，中红外波段（1.2μm～10.6μm）激光光束采用扫描狭缝法测量激光束散角。两种方法的结合可以较为精确地测量出不同波段的激光束散角。

Calibration method for high-power and wide-band laser beam divergence angle

In the evaluation and analysis of high-power laser system, the beam quality of laser is the decisive factor of the system beam quality and also an important index of acceptance and appraisal of laser, among which the beam divergence angle is an important parameter to identify the laser beam quality. The range of laser wavelength tested in this system is relatively wide, generally between 0.532 μm~10.6 μm, and no suitable detector can cover the whole band. Therefore, a new method was adopted to solve the measurement problem of wide-band beam divergence angle. The method of combining charge coupled device (CCD) imaging and scanning slit was used to measure the wide-band beam divergence angle. The CCD method was used to measure the laser beam divergence angle in visible and near-infrared band (0.532 μm~1.2 μm), and the scanning slit method was used to measure the laser beam divergence angle in mid-infrared band (1.2 μm~10.6 μm). The combination of the two methods can accurately measure the laser beam divergence angle in different wavebands.