激光光束质量因子M2对激光粒度仪测量结果的影响

Influence of Laser Beam Quality Factor M2 on Measurement Results of Laser Particle Sizer

摘要: 激光粒度仪是新兴的颗粒物粒度分析的检测设备，其以激光器作为照明的重要组件。激光光束质量因子M2是对激光器系统进行质量监控及辅助设计的评价标准。本文在分析了颗粒粒度分布函数和激光粒度仪工作原理之后，又着重介绍了激光光束质量因子M2对激光粒度仪测量结果的影响。研究结果表明，M2因子主要是从光束发散角和光束束腰宽度两个方面导致仪器的测量结果产生误差。举例分析、模拟仿真得出以下结论：光束发散角的大小与误差值成正比，即发散角越小，则误差越小；在M2因子选取范围内(1~1.8)，光束束腰宽度对仪器的测量结果的影响可以忽略不计。又M2因子与光束发散角是正比关系，与光束束腰宽度成反比，因此，M2因子愈小，对激光粒度仪测量结果造成的误差就愈小。为此，研究M2因子对激光粒度仪测量结果的影响就显得尤为重要了。

Abstract: The laser particle size analyzer, the laser as the important component of the illumination, is a new equipment for the particle size analysis of the particle. The laser beam quality factor M2 is an evaluation standard for the quality control and aided design of the laser system. After analyzing the particle size distribution function and the working principle of laser particle sizer, the effect of laser beam quality factor M2 on the measurement results of Laser Particle Sizer is emphasized. The results show that the M2 factor mainly results from the two aspects of the beam divergence and the waist width of the beam. The simulation example analysis draws the following conclusions: The size of the beam divergence angle is proportional to the error value, that is, the smaller the divergence angle, the smaller the error. In the M2 factor selection range (1 ~ 1.8), the influence of the beam waist width on the measurement results of the instrument is negligible. Moreover, the M2 factor is directly proportional to the beam divergence angle and inversely proportional to the beam waist width. Therefore, the smaller the M2 factor, the smaller the error caused by the laser particle sizer. Therefore, it is very important to study the influence of M2 factor on the measurement result of laser particle sizer.