高功率环形激光二极管阵列重复脉冲抽运激光器中棒的瞬态温度分布

Analysis of transient temperature distribution in laser rod pumped by repetitively pulsed high-power ring-LDA

采用光线追迹方法和有限元方法,对高功率环形激光二极管阵列(LDA)重复脉冲抽运Nd:YAG激光器中,棒的瞬态温度分布进行了详细的计算模拟,分析比较了不同抽运阶段、抽运频率及占空比的情况下棒内的瞬态温度分布。结果表明:高功率环形LDA重复脉冲抽运时,棒中心处温度随时间变化成锯齿形分布,棒内温度随抽运频率和占空比的增大而增大,最后温度随时间成周期性变化。

The transient temperature distribution in the Nd:YAG laser rod repeatedly pulse-pumped by high power ring-LD array was simulated by using ray tracing method and finite element method. The transient temperature distributions at different pump periods, pump frequencies and pump widths were analyzed and compared. The result indicated that when high power ring-LD array pumped repeatedly, the core temperature of the rod had sawtooth distribution, and the temperature of the rod rose as the pump frequency or pump width rose. The temperature had periodical distribution with time.