激光二极管端面抽运Nd∶YVO_4固体激光器热致光束畸变非对称的平衡

Balance of Asymmetry of Thermal Beam Distortion in Laser Diode End-Pumped Nd∶YVO_4 Solid State Lasers

由于a轴切割Nd∶YVO4晶体的非对称性,使得激光二极管(LD)端面抽运Nd∶YVO4固体激光器不同于Nd∶YAG激光器,输出的激光经常产生非对称结果。用有限元法分析激光二极管端面抽运a轴切割Nd∶YVO4固体激光器的晶体热效应,包括温度分布、内部应力和产生的形变。分析结果表明端面抽运a轴切割Nd∶YVO4晶体产生了椭球热透镜效应。从结构方面和抽运方面提出了热透镜非对称性的平衡方法,实验验证了方法的可行性。

The asymmetry of a-cut Nd： YVO4 leads to asymmetrical laser output from laser diode （LD） end-pumped Nd： YVO4 solid state laser, which differs from Nd： YAG laser. The finite element was applied to analyze the thermal effect of LD end-pumped a-cut Nd ： YVO4 crystal, including temperature distribution, internal stress and its deformation. The results indicate that the thermal lens of end-pumped a-cut Nd： YVO4 crystal takes the ellipsoidal distribution. The method of balancing the asymmetry of thermal lens was put forward by the way of structure and pumping, and experimentally proved feasible.