端面形变对端泵DPL参数的影响

Thermal effect of end deformation on the parameters of end pumped DPL

以二极管端面泵浦固体激光器(DPL)为研究对象,研究了端面形变热效应对DPL参数的影响。将温度梯度和引力双折射热透镜效应等效为一个焦距为f的薄透镜,将端面形变等效为曲率半径为r的球面反射镜,根据谐振腔理论进行计算机模拟,将端面形变热效应从总的热效应中分开,研究发现,当引起的端面形变的曲率半径大于300mm以后,温度梯度和引力双折射热透镜效应对DPL发散角的影响不大(腔长100mm),而端面形变热效应对其有很大的影响。结果表明,随着端面形变参数r的减小,其输出振荡光的发散角和束腰半径越来越大。此研究直接指导端泵DPL的端面形变研究。依据此结论,就可直接从腔外通过测其远场发散角算出端面形变的大小。

Effect of the end deformation on the parameters was studied in the diode pumped solid- state laser.The temperature grade and gravitation double refraction thermal lens effect is regarded as one lens, whose focus is f. The end deformation is regarded as a sphere reflector, whose curvature radius is r. According to the oscillatory cavity theory, the deformation vs walk off angle and deformation vs waist radius can be simulated.The radiation angle and waist radius increase as the curvature radius of the end deformation decreases, and the conclusion is drawn that the temperature grade and gravitation double refraction thermal effect have little effect on the radiation angle when the radius is more than 300 mm.Therefore, the deformation can be measured by the radiation angle outside the laser.