直接液体冷却薄片激光器中抽运光均匀性对光束波前畸变的影响

近年来,直接液体冷却薄片激光器因其体积功率比小,热管理能力强等优势而成为研究热点.本文建立了一套直接液体冷却薄片激光器波前畸变的分析方法.应用该方法研究了直接液体冷却薄片激光器中抽运光均匀性对光束波前畸变的影响.计算分析了均匀性为92%, 80%和70%,且总的抽运功率不变时,激光器高阶像差分布情况.随着均匀性逐渐减弱,激光器中高阶像差逐渐增强,低阶像差量基本保持不变.实验中,设计加入波导和未加入波导结构,构建了均匀性为92%和70%的抽运光分布,分别测量了两种情况下的波前抖动情况以及波前畸变分布,抽运功率为5 k W时,测量获得了整个增益模块的光程差高阶分量(OPD_H),其畸变量均方根(RMS)值为0.66μm和0.79μm,实验结果和理论分析结果基本趋势一致.

Influence of pumping light uniformity on laser wavefront aberration in direct-liquid-cooled thin-disk laser

In recent years,the direct-liquid-cooled thin-disk lasers have become ahot research topic due to their advantages of extremely small volume to output power ratio and strong thermal management ability.A method of analyzing the wavefront aberration of the direct-liquid-cooled thin-disk laser is established in this paper.The influence of pumping light uniformity on the wavefront aberration is investigated by this method.The high order aberration distribution of the laser beam is calculated,when the uniformity is 92%,80%and 70%,respectively.With the decrease of beam uniformity,the higher order aberrationsincrease gradually,while the low order aberrations remain basically unchanged.Experimentally,the pumping beam distributions respectively with uniformity of 92%and 70%are designed with and without using the waveguide structure.The wavefront jitter and wavefront aberration distribution of the whole gain module are measured in these two cases.The pump power is kept at 5 kW.The higher order of optical path difference(OPDH)values of the whole gain module are measured to be 0.66μm and 0.79μm,respectively.The experimental results are in agreement with the theoretical analyses.