A new slab configuration is designed based on the traditional Yb:YAG Total-Reflection Active-Mirror (TRAM) slab laser. The grad-doping method is proposed to improve the pump uniformity of the gain medium. A thermal analysis model is established by the ray-tracing software and finite element method. The thermal effects of the uniform doping medium and gradient doping medium are investigated according to the model, respectively. It shows that the maximum temperature and stress decrease obviously by the grad-doping method. A method based on ray-tracing is proposed to evaluate the thermal lensing effect and spherical aberration effect, and it is also suitable for other gain mediums with complex structures. The results indicate that the gain medium has less thermal effect and better beam quality by the grad-doping method. The TRAM slab with gradient doping concentration is also a promising configuration to obtain higher power output.

基于传统的 Yb:YAG 全反射有源反射镜 (TRAM) 板条激光器设计了一种新的板条配置。提出了梯度掺杂方法来提高增益介质的泵浦均匀性。利用射线追踪软件和有限元方法建立了热分析模型。根据模型分别研究了均匀掺杂介质和梯度掺杂介质的热效应。结果表明，梯度掺杂法使最高温度和应力明显降低。提出了一种基于光线追踪的方法来评估热透镜效应和球差效应，也适用于其他结构复杂的增益介质。结果表明，梯度掺杂的增益介质具有较小的热效应和较好的光束质量。