正交狭缝扫描式激光光束质量测量方法研究  

Research on measurement method of laser beam quality with orthogonal slit scanning

作　　者：赵俊成 阴万宏[1] 刘建平[1] 杨朋利[1] 董再天 ZHAO Juncheng;YIN Wanhong;LIU Jianping;YANG Pengli;DONG Zaitian(Xi’an Institute of Applied Optics,Xi’an 710065,China)

机构地区：[1]西安应用光学研究所,陕西西安710065

出　　处：《应用光学》2020年第4期704-710,共7页Journal of Applied Optics

基　　金：国防技术基础项目(JSJL2018208B001)。

摘　　要：传统激光光束质量测量方法在CCD相机靶面前激光光路上加装可调衰减模块,对激光光束进行衰减。但该方法受限于CCD相机像元尺寸限制,难以进行高精度测量。为此该文提出了一种滚轮狭缝式激光光束质量评价方法,在测量时采用狭缝滚轮上的扫描狭缝直接扫描被测激光光束,使用InGaAs探测器配合聚焦透镜进行测量。经过与电机同轴的高精度增量式编码器确保采集位置与采集数据同步,扫描频率根据被测激光脉冲频率和光斑的直径范围可进行调整,该方法对光斑空间采样分辨率优于1μm。实验结果表明,采用该方法测得的激光M^2因子数值与被测激光器提供数值一致,测量不确定度小于10%。In the traditional laser beam quality measurement method, an adjustable attenuation module is installed on the laser beam path in front of the change coupled device(CCD) camera target to attenuate the laser beam. However, the high-accuracy measurement is difficult to carry out due to the limitation of CCD camera pixel size by this method. On this basis, an evaluation method of laser beam quality with roller slit was proposed. In the measurement, the scanning slit on the slit roller was used to directly scan the measured laser beam, and the InGaAs detector was used to cooperate with the focusing lens for measurement. The highaccuracy incremental encoder was coaxial with the motor, which ensured the synchronous acquisition of position and data. According to the measured laser pulse frequency and the diameter range of the spot, the scanning frequency could be adjusted, and the resolution of spot spatial sampling was better than 1μm. The experimental results show that the value of laser M^2 factor measured by this method is consistent with that provided by the measured laser, and the measurement uncertainty is less than 10%.

关 键 词：激光光束质量 狭缝 转动滚轮 扫描频率 

分 类 号：TN202[电子电信—物理电子学]