报道了一种基于Nd∶YVO4/MgO∶PPLN的高效连续单谐振连续中红外光学参量器.采用LD泵浦的输出波长为1 064 nm的连续Nd∶YVO4 激光器作为入射光，经过MgO∶PPLN晶体进行非线性频率转换.理论分析了非线性晶体的周期、温度对光学参量振荡量输出波长的影响.提出采用紧凑的平平腔结构，利用多周期的MgO∶PPLN晶体(29.52~31.59 μm)，产生宽带可调谐的中红外激光，其信号光调谐范围为1.48~ 1.63 μm；闲频光调谐范围为3.0~3.8 μm.结果表明：在MgO∶PPLN的极化周期为30.5 μm，温度为100℃的条件下，当808 nm泵浦光功率为8.06 W时，获得最高760 mW的信号光和360 mW的闲频光输出，对应光光转换效率为13.9%.

An efficient tunable, continuous-wave, mid-infrared, intra-cavity singly resonant Nd∶YVO4/MgO∶PPLN optical parametric oscillator is presented. A laser-diode-pumped 1 064 nm laser is taken as the incident light and a MgO∶PPLN crystal is used for frequency conversion. The variation of the mid-infrared output wavelength with the grating period and temperature of nonliear crystal is investigated. The grating period of multi-grating MgO∶PPLN chip is from 29.52 to 31.59 μm by a step of 0.5 mm. The tuning wavelength of the signal light is from 1.48 to 1.63 μm and that of the idle light is 3.0 to 3.8 μm. A maximum signal power of 760 mW and idler power of 360 mW are obtained under a pump power of 8.06 W at 808 nm, with corresponding to a total optical efficiency being 13.9% when the grating period is 30.5 μm.