分区域主动冷却薄片激光介质的理论和实验研究

Theoretical and experimental research on district cooling for thin disk-type laser medium

针对薄片激光介质抽运和温度分布不均匀的问题,设计了分区域主动冷却控制薄片激光器.根据热传导方程,对端面抽运方形薄片激光介质在均匀冷却和分区域主动冷却两种冷却方式下的温度和应力分布进行了模拟计算.结果显示:分区域主动冷却能使薄片介质横向温度分布趋于均匀,相对于均匀冷却时最大温差的改善率达到了约86%,介质边缘的张应力转变为低值压应力,有效地抑制了热应力炸裂.搭建了分区域主动冷却控制实验装置,并进行了验证实验,实验结果与模拟结果相符.为薄片激光器的热管理方式提供了新的思路.

For the non-uniform pumping and cooling to the thin disk-type laser medium, the district cooling method for thin disk-type laser medium is proposed and examined both experimentally and theoretically. Based on heat conduction equation, the distributions of temperature and stress in end pumping thin disk-type laser medium with evenly cooling and district cooling are calculated. The results show that the tensile stresses on the edge of gain medium with evenly cooling are changed into the low values of compressive Stresses for the case of district cooling, and the distribution of temperature in medium with district cooling is much more uniform than with evenly cooling, the ranges of temperature reduces about 86%, and this result is consistent well with the experimental result. The district cooling method could provide a new way of thermal management for thin disk-type laser.