激光二极管侧抽运长方形Nd:YVO4激光晶体热分析

以解析分析理论为基础,研究长方形Nd∶YVO4激光晶体受到具有高斯分布半导体激光侧端面抽运时,晶体温度场和热形变的分布情况。通过对激光二极管(LD)侧面抽运晶体工作特点分析,建立了符合实际工作情况的热模型,利用正交各向异性材料热传导方程,得出长方形Nd∶YVO4晶体温度场和热形变场通解表达式,并提出了两种有效减小晶体热形变的方法。研究结果表明,当使用输出功率为30 W的激光二极管侧面中心抽运Nd∶YVO4激光晶体时,在抽运端面中心获得240.0℃最高温升和4.73μm最大热形变量。偏心0.6 mm时,端面最大热形变量减少31.1%。晶体厚度减小30%时,端面最大热形变量减少23.5%。

Thermal Analysis of Rectangular Nd: YVO4 Crystal by Laser Diode Side-Pumped

Based on analytical theory, the temperature field and the pumped-face thermal distortion of a rectangular Nd:YVO4 laser crystal side-pumped by a diode laser with Gaussian distribution were investigated. By analyzing the working characteristics of the laser diode (LD) side-pumped crystal, thermal physical model according with actual working conditions was built, the general expressions of temperature field and thermal distortion field of rectangular Nd:YVO4 crystal were obtained by using a new solution in heat conduction equation of orthogonal anisotropic material. Two methods of effectively reducing thermal distortion were presented. The research results showed that the maximum temperature rise of 240.0 ℃ and the maximum thermal distortion of 4.73 μm can be obtained in the center of the pump side-surface when the output power of the diode laser is 30 W. If eccentric pump center is 0.6 mm, the maximum thermal distortion is reduced by 31.3%. And if the thickness of crystal is reduced by 30%, the maximum thermal distortion is reduced by 23.5%.