高重复频率、高峰值功率、窄线宽的激光在激光雷达领域具有重要的应用价值。在对高重频窄线宽激光进行放大时, 为了同时实现高放大倍率与高光束质量激光输出, 在高重频、窄线宽被动调Q激光器作为种子源的前提下, 设计了利用888 nm半导体激光端面泵浦Nd:YVO4块状晶体实现高增益的一级放大, 808 nm半导体激光侧面泵浦Nd:YVO4板条晶体实现低热透镜效应的二级放大的方案。在重复频率10 kHz时, 获得了峰值功率5 MW, 线宽154 pm, 脉冲宽度0.6 ns, 平均功率31.5 W, 光束质量M2为1.98的激光输出。从而验证了将高放大倍率与高光束质量分别控制的放大器设计思路。

The laser with high repetition rate, high peak power and narrow line width has important application value in the field of laser radar. In the amplification of high repetition frequency and narrow line width laser, in order to achieve both high magnification and high beam quality laser output at high repetition rate, narrow line width of passively Q-switched laser used to be the seed source, high gain amplifier using 888 nm diode laser end pumped Nd:YVO4 crystal, side pumped Nd:YVO4 slab crystal thermal lens effect of two stage amplification scheme were designed. At the repetition rate of 10 kHz, the average power of 31.5 W, and the laser beam quality of M2 1.98 were obtained. The peak power was 5 MW, the line width was 154 pm and the pulse width was 0.6 ns. Thus, the design idea of amplifier with high magnification ratio and high beam quality control individually was verified.