在激光二极管(LD)抽运固体激光器中, 激光晶体温度存在空间和时间分布, 其中空间分布在许多论文中已得到讨论, 而时变特性现有文献涉及较少, 它取决于激光器的抽运方式(连续和脉冲), 在脉冲工作状态中存在热效应时变过程。分别采用解析计算法和有限元分析软件, 对脉冲激光二极管抽运激光晶体温度场的时变特性进行计算, 分析晶体升温和降温过程影响因素。结果表明,升温过程受到抽运及散热条件的影响, 但主要受抽运条件(抽运光强度和光束半径)影响; 降温过程受晶体半径、热物性参数及散热条件的影响。在脉冲激光二极管抽运条件下晶体径向温度梯度的周期性波动引起谐振腔呈周期性变化, 通过合理设计谐振腔, 可使其周期性运转在稳腔和非稳腔状态下, 以获得特定的激光输出。

In laser diode (LD) pumped solid state laser, spatial and time distribution of temperature both exist in crystal, spatial distribution is discussed much more than time distribution in many papers. The time distribution of temperature lies on the pumped mode of laser such as CW pumped and pulsed pumped, time-varying process exists in pulsed condition. Analytic method and finite element software are both used in the calculation of temperature time-varying distribution in laser diode pumped solid state laser, the influences of heating and cooling process are analyzed. The results show that heating process is influenced by pumped and cooling conditions, but mainly by pumped conditions such as pumped power and beam waist, cooling process is influenced by crystal radius, thermal physical parameters and cooling condition. Under the condition of pulsed laser diode pumped, radial temperature gradient and the resonator periodically change with time. After reasonable designing the resonator, lasers can periodically work in steady and unsteady states, which can obtain specifically laser output.