报道了一台采用激光二极管(LD)侧面抽运Nd∶YAP晶体的全固态腔内三倍频447 nm连续(CW)蓝光激光器。对几种常用的晶体进行分析对比后, 选取Nd∶YAP晶体作为增益介质产生1341.4 nm基频光, 腔内采用Ⅰ类临界相位匹配(CPM)LBO晶体进行倍频(SHG)产生670.7 nm波长激光, 基频光与倍频红光再经Ⅱ类临界相位匹配的KTP晶体和频(SFM)获得447.1 nm蓝光输出。采用四镜折叠腔结构, 通过谐振腔稳定性分析, 优化选取了合适的谐振腔参数。实验对比了不同腔长的输出特性, 最终在534 W抽运功率下, 获得了最高功率为114 mW的连续447.1 nm蓝光输出, 光-光转换效率为0.02%, 并分析了效率低的原因。

A laser-diode (LD) side-pumped Nd∶YAP all-solid-state intracavity frequency-tripled 447 nm continuous-wave (CW) blue laser was reported. After analysis and comparison of several optical crystals, Nd∶YAP was chosen as the gain medium to generate 1341.4 nm fundamental laser. Inside the cavity, a type Ⅰ critical phase matching (CPM) LBO crystal was used for 670.7 nm second harmonic generation (SHG), and a type Ⅱ CPM KTP was used for sum frequency mixing (SFM) of the 1341.4 nm and 670.7 nm radiation to generate 447.1 nm blue light. By using a four-mirror folded-cavity resonator, the parameters of laser cavity were optimized and selected according to cavity stability analysis. Output characteristics of different cavity lengths were studied by experiment. The output power of 447.1 nm CW blue laser reached 114 mW at the incident pump power of 534 W, corresponding to an optical-to-optical conversion efficiency of 0.02%, and the causes of low efficiency were analyzed.