报道了1064nm单频激光抽运的KTP晶体外腔单谐振光参量振荡器(OPO),获得了波长为2.05μm的纳秒激光脉冲输出。在平-平腔中,将2块II类相位匹配KTP晶体按走离补偿方式放置,在400 Hz重复频率下,抽运单脉冲能量达到5mJ时获得了单脉冲能量为0.9mJ的2.05μm信号光输出,其脉宽约为3.7ns,对应抽运光-信号光转换效率约为18%,光束质量因子M~2在x、y方向分别为2.08、3.03。 A 1064nm single-frequency laser-pumped KTP crystal single-cavity single-oscillator optical parametric oscillator (OPO) is reported, and a nanosecond laser pulse with a wavelength of 2.05μm is obtained. In the flat-cavity, two phase-II matched KTP crystals were placed in a compensation-free manner. At a repetition rate of 400 Hz, a 2.05 μm signal light with a single pulse energy of 0.9 mJ was obtained with a single pulse energy of 5 mJ The pulse width is about 3.7ns, corresponding to the pumping light - signal light conversion efficiency of about 18%, the beam quality factor M ~ 2 in the x, y direction were 2.08,3.03.