摘要
在脉冲激光二极管(LD)泵浦的激光晶体中存在升降温的时变过程,为解决脉冲LD端面泵浦的激光晶体产生的热效应问题,基于热传导方程,采用特征函数法和常数变异法得到了脉冲超高斯光束端面泵浦Nd:YAG棒的时变温度场的一般解析表达式。同时定量分析了单脉冲和重复脉冲端面泵浦Nd:YAG棒的时变温度规律。研究结果表明,重复脉冲端面泵浦Nd:YAG棒时,棒内温度随时间呈锯齿状变化,经过一段时间后最终呈稳定的周期性分布;棒内温度也随泵浦脉冲束腰半径的减小和占空比的增大而增大;脉宽越宽时,棒内温度的波动幅度也越大。研究方法和所得结果还可以应用到激光系统的其他时变热问题的研究中,对解决激光系统的热问题具有理论指导作用。
The time-varying processes of temperature rise and fall exist in laser crystal pumped by pulsed laser diode （LD）. In order to solve the thermal effect of laser crystal end-pumped by pulsed LD, a general analytical time-varying temperature filed expression of Nd：YAG rod end-pumped by the pulsed supper- Gaussian beam was obtained by the methods of eigen-function and constant variation, based on the heat conduct equation. Meanwhile, the time-varying temperature laws of Nd：YAG rod end-pumped by single pulse and repeat pulses were quantitatively analyzed. The results show that when repeat pulses end-pump Nd：YAG rod, the temperature of the rod has saw-tooth distribution with time, and has periodically stable distribution after some time. The temperature of rod rises as duty cycle of pump pulse rises and beam waist radius decreases. The decrease of pulse width will reduce the temperature fluctuation range of rod. The research methods and results can also be used to analyze other time-varying thermal problems in laser systems, and will play theoretically a directional role in solving thermal problems in laser systems .
出处
《红外与激光工程》
EI
CSCD
北大核心
2011年第9期1657-1661,共5页
Infrared and Laser Engineering
基金
西安市科技局创新支撑计划(CXY1015(6))
陕西省教育厅专项科研资助项目(11JK0532)
