研制了输出功率达瓦级的351 nm准连续紫外激光器。激光器采用激光二极管(LD)端面抽运Nd∶YLF晶体和声光调Q技术, 实现了1 053 nm准连续基波振荡。在结构简单的V型腔中, 两块LiB3O5(LBO)晶体对基频光进行二倍频和三倍频, 获得了高功率351 nm准连续紫外激光输出。在LD抽运功率为14 W、声光调Q激光器的调制频率为 1 kHz 的工作条件下, 得到351 nm紫外激光平均输出功率为1.12 W、脉冲宽度为34 ns、单脉冲能量为1.12 mJ、峰值功率达32.94 kW。 LD抽运光到351 nm紫外激光的光-光转换效率达到8%, 电光效率为3.4%, 光束质量良好。

A watt-class quasi-continuous 351 nm ultraviolet laser was fabricated by using frequency-doubled and frequency-tripled the radiation at 1 053 nm from laser diode (LD) end-pumped Nd∶YLF crystal under acoustic-optical Q-switched in a simple V-shaped cavity with two LiB3O5(LBO) crystals. An average output power at 351 nm of 1.12 W is obtained at repetition rate of 1 kHz and pumped power of 14 W. The single pulse energy is 1.12 mJ with the pulse width of 34 ns at 351 nm, and the peak power is up to 32.94 kW. The optical-optical conversion efficiency is 8%, and the electro-optical conversion efficiency is 3.4%. The beam quality is satisfactory.