LD抽运355nm连续紫外激光器

LD pumped all-solid-state continuous-wave ultraviolet laser

报道了一台LD端面抽运Nd:YVO4晶体的内腔三次谐波转换的全固态连续紫外激光器。在谐振腔内,1064nm的基频波经Ⅱ类相位匹配KTP晶体进行二倍频产生532nm波长激光,二者再经Ⅰ类相位匹配LBO晶体进行和频获得355nm紫外激光输出。在Nd:YVO4晶体的外端镀1064nm/532nm双波长高反膜作为输入镜,其与输出镜构成平-凹腔结构,并考虑到Nd:YVO4晶体所产生的热透镜效应,对腔长进行了详细的分析计算。当LD抽运功率为3W时,获得4.2mW连续运转的355nm紫外激光。

A laser-diode （LD） pumped Nd：YVO4 intracavity frequency tripling all-solid-state Continuous-wave （CW） ultraviolet laser at 355 nm was reported. In cavity, the type Ⅱ phase-matched KTP crystal was used for Second Harmonic Generation （SHG） of the fundamental 1064 nm radiation to generate 532 nm radiation, and the type Ⅰ phase-matched LBO crystal was used as a Sum Frequency （SM） of the 1064 nm radiation and the 532 nm radiation to generate 355 nm radiation. The flat outside section of the Nd：YVO4 crystal HR coated for both 1064 nm and 532 nm radiations was used as the input mirror. The output mirror was concave. Therefore, piano-concave cavity was composed of these two mirrors. Even at moderate pump power, the Nd：YVO4 crystal will produce thermal lens. In considering the effect of thermal lens, the cavity was designed finely. At the pump power of 3W, the CW 355 nm radiation of 4.2 mW was obtained.