Attenuation of high rate in parameter measurement of high power laser

在高功率激光参数测量中,高倍率衰减方案设计是空间分布测量的关键。分析了远场测量光学系统,将95%环围能量直径作为评价远场测量系统的重要指标,明确了高倍率衰减对远场测量结果的影响,确立了高倍率衰减方案的设计原则。利用Virtual Lab软件,针对单个平板、成对平板、成对楔板三种常见的高倍率衰减方案,分析了衰减片摆放角度、位置、厚度、成对衰减片间距等因素对于远场测量系统的影响。针对焦距3 000 mm,F数为10的缩束系统,考虑杂散光对于远场测量的影响,优化得出最佳高倍率衰减方案。该方案下,远场像面处95%In high power laser beam parameters measurement, attenuation scheme with high rate is key to far-field measurement. The far-field optical measurement system was analyzed and diameter of 95% encircled energy was used as important evaluation criterion of far-field measurement system. Measurement error of far-field optical measurement system and effect of attenuation with high rate on far-field measurement results were analyzed. Principle of attenuation scheme with high rate was established. By changing parameters of high attenuation rate in condition of single parallel plate, a pair of parallel plates and a pair of wedge flaps by Virtual Lab, influence of attenuation on the far-field measurement system was simulated and analyzed deeply. According to measurement system for f =3 000 mm and F =10, best attenuation scheme with high rate is designed. Diameter of 95% encircled energy of far-field image is 45.5 μm, or 3.54 times of diffraction limitation. ? 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved