In the amplifier of large-aperture laser device, laser slabs will produce depolarization in the stress concentration area due to mounting and heat. The depolarization makes the laser isolation ratio unable to meet the design requirements, and there will be uncontrolled light passing through it that will amplify itself in the system and cause unpredictable damage to the slabs. It causes damaged to other optical components even more easily, and the polarization quality of the laser is also reduced, which has a considerable impact on the efficiency of the device as a result. Aiming at this problem, this paper describes the physical mechanism of the polarization characteristics of slabs caused by mounting stress and thermal stress, and puts forward the regular pattern of the assembly process parameters on the polarization characteristics of the slabs. And a series of experiments are launched to verify these mechanism and regular pattern, and also provide a method basis for optimizing its polarization characteristics.

在大口径激光设备的放大器中，由于安装和加热，激光平板将在应力集中区域产生去极化。消偏振使激光隔离率无法满足设计要求，并且会有不受控制的光通过，这会在系统中放大自身，并对板坯造成不可预测的损坏。这甚至更容易导致对其他光学组件的损坏，并且激光的偏振质量也降低了，因此对设备的效率产生了很大的影响。针对这一问题，本文描述了板坯在安装应力和热应力作用下的极化特性的物理机理，并提出了组装工艺参数对板坯极化特性的规律规律。