高重复频率大能量窄脉宽激光器在激光成像、激光加工、精密测量等领域中得到广泛应用。采用电光腔倒空技术和双棒串接结构, 通过减小热透镜效应的影响并保证振荡光与抽运光的良好模式匹配, 实现了高效率、大能量、窄脉宽1064 nm 线偏振脉冲激光输出。以偏硼酸钡(BBO)普克尔盒作为电光开关, 采用低吸收系数的914 nm光纤耦合半导体激光器端面抽运Nd∶YVO4晶体, 提高了激光器的热稳定性。在重复频率7 kHz的条件下, 当谐振腔腔长为450 mm, 晶体吸收功率为79.6 W时, 获得了脉冲宽度为5 ns, 最大平均输出功率为35 W, 单脉冲能量为5 mJ的稳定脉冲激光输出, 对应的光-光转换效率为44%。

High repetition rate, large energy and narrow pulse width laser is widely used in the frontier fields of laser imaging, laser machining and precision measurement. Using the technology of electro-optical cavity-dumped and double rod series structure, which reduces the thermal lens effect and ensures the good matching mode of oscillation light and the pump light, the 1064 nm linearly polarized laser output with high efficiency, large energy and narrow pulse width is realized. Using the barium boron oxide (BBO) Pockels cell as electro-optical switch, and the 914 nm fiber-coupled semiconductor laser with low absorption coefficient is used to pump the Nd∶YVO4 crystal. Thus the thermal stability of the laser is improved. At the repetition rate of 7 kHz and the crystal absorption power of 79.6 W, a stable pulse laser output with a pulse width of 5 ns, maximum average output power of 35 W, and a single pulse energy of 5 mJ is obtained, and the corresponding optical conversion efficiency is 44%.