为了获得简单紧凑的固体激光器, 采用半导体端面抽运三程折叠谐振腔板条激光器, 建立了热透镜等效腔模型, 进行了等效腔稳定性及腔内基模光斑半径的仿真分析, 将新型结构与平-平腔结构进行了比对性实验研究。结果表明,在三程折叠腔长为170mm时, 获得了21W的1064nm激光功率输出, 光光转换效率为16.4%, 斜效率为25%, 水平和竖直方向上的M2因子分别为10.8和2.76。同等条件下, 水平方向上M2因子从平-平腔的152.7优化到三程折叠腔的10.8; 输出光斑水平方向尺寸由平-平腔的10.8mm压缩到三程折叠腔的4.1mm,验证了结构简单紧凑的端面抽运三程折叠谐振腔激光器光束的输出能力。该研究对获得腔内调Q和腔内倍频532nm激光器有实际意义。

In order to obtain simple and compact solid-state lasers, a LD end-pumped slab laser with a folded three-pass resonator was used and its thermal lens equivalent cavity model was established. The equivalent cavity stability and cavity mode radius were simulated and analyzed. The new structure and flat cavity structure were studied comparatively based on experiments. The results show that, when the length of the folded three-pass cavity is 170mm, the power output of 1064nm laser is 21W, light-light efficiency is 16.4%, slope efficiency is 25%, and M2 factors in horizontal and vertical directions are 10.8 and 2.76 respectively. Under the same conditions, M2 factor in horizontal direction is improved from 152.7 of the parallel-plane resonator to 10.8 of the folded three-pass cavity. The horizontal direction of output spot is compressed from 10.8mm of the parallel-flat cavity to 4.1mm of the folded three-pass cavity. Beam output capability of the simple and compact end-pumped laser with a folded three-pass resonator is verified. The study is of practical significance for obtaining intracavity Q-switched and intracavity frequency-doubled 532nm lasers.