研制了全固态连续波570 nm黄光激光器，黄激光分别由两片Nd∶YAG的1 444 nm和946 nm谱线非线性和频产生，两条谱线分别对应各自的晶体能级跃迁4F3/2-4I15/2和4F3/2-4I9/2。实验采用复合腔结构，利用KTP晶体II类临界相位进行内腔和频。测量了570 nm黄激光输出功率随泵浦功率的变化，结果表明，当注入到两片Nd∶YAG晶体的泵浦功率分别为24 W和15 W时，获得了560 mW的连续波570 nm黄激光输出，其4 h功率稳定度优于±2.8％。在输出功率为560 mW时，采用光束质量分析仪测量了激光输出光斑质量，结果显示，在570 nm最大和频激光输出时的光束质量因子M2为2.3。所提出的复合内腔和频技术可为新波长激光器的发展提供参考。

An all solid-state continuous-wave yellow laser at 570 nm is firstly reported.The yellow laser is from two Nd∶YAG spectral lines of 1 444 nm and 946 nm with a nonlinear sum frequency,and the two spectral lines correspond to their energy levels of crystal transition for 4F3/2-4I15/2 and 4F3/2-4I9/2, respectively.By using a doubly folded-cavity, the yellow laser at 570 nm is obtained by a intra-cavity sum frequency mixing of type-II critical phase matching KTP crystal at 1 444 nm and 946 nm.The outpower of yellow laser vs incident pump powers is measured,results indicate that when pump powers injected into two Nd∶YAG crystals are 24 W and 15 W, respectively, the 570 nm yellow laser of 560 mW can be obtained,and its power stability in 4 h is better than ±2.8%.Furthermore,the beam quality of the yellow laser is measured by a beam quality analyzer in an output power of 560 mW, and results show its beam quality factor M2 is 2.3 in the laser with a maximum sum-frequency output.