提出了定量表征激光棒内吸收抽运光分布均匀性特征参量——吸收抽运光分布均方根偏差相对值, 利用该参量以及自行编制的光线追迹程序, 定量分析了五向侧面抽运Nd∶YAG模块内吸收抽运光分布均匀性及耦合吸收效率随激光二极管(LD)Bar条与Nd∶YAG棒表面间距的变化规律, 确定了侧面抽运模块优化结构参数; 在此基础上研制了抽运频率为100 Hz, 占空比为2%的侧面抽运Nd∶YAG模块, 其808 nm最大平均抽运功率为200 W, 1064 nm短腔最大输出功率为95 W, 光-光转换效率为47.5%。

A parameter that quantificationally evaluates the homogeneity of the absorbed pump light distribution in a laser rod is proposed, which is root mean square error relative value of absorbed pump light distribution in the laser rod. By using this parameter and the ray tracing code, the couple efficiency and the pump light distribution homogeneity of a five-fold side-pumped Nd∶YAG module for different distance between LD and the side surface of the Nd∶YAG rod are quantificationally investigated, and structure parameters are optimized. At 100 Hz and 2% duty cycle, the maximum average pump power of the module at 808 nm is 200 W. Arranging one such pump module in a plane-plane short cavity, 95 W multi-mode laser output at 1064 nm can be delivered. The corresponding optical to optical efficiency is 47.5%.