LD抽运355-nm准连续紫外激光器

LD Pumped 355-nm Quasi-CW Ultraviolet Laser

报道了激光二极管(LD)侧面抽运Nd:YAG激光晶体腔内三倍频355 nm紫外激光器。实验中采用声光调Q技术,选用结构简单、紧凑的三镜折叠、平-凹腔设计,在腔内对1064 nm基波采用Ⅰ类相位匹配LiB3O5(LBO)晶体二倍频、Ⅱ类相位匹配LBO晶体实现三倍频,获得了较好光束质量的准连续紫外激光输出。在激光二极管抽运功率为155 W,声光调Q的调制频率为5.40 kHz的工作条件下,获得脉宽为45 ns,最高平均输出功率为2.14 W,光场均匀分布的355 nm准连续紫外激光,808 nm抽运光到355 nm紫外激光的光-光转换效率达到1.38%,1 h内输出稳定性为3.30%。此外,对影响腔内三倍频转换效率的因素进行了相应的分析研究。

A LD side-pumped Nd ： YAG all-solid-state ultraviolet laser is demonstrated under acousto-optic Q- switched operation, by using a simple and compact three-mirror folded and flat-concave cavity resonator, with type Ⅰ phase-matched LiB3O5 （LBO） as second harmonic generation crystal and type Ⅱ phase-matched LBO as third harmonic generation crystal. The output power of 355-nm UV laser reaches to 2.14 W at the incident pump power of 155 W and repetition rate of 5.40 kHz with pulse width of 45 ns. The light-light conversion efficiency is about 1. 38 %, and the power stability is 3.30% in 1 h operation accordingly. The influence factor on the triple frequency conversion efficiency is studied.