利用自制的高功率连续单频1.06 μm激光器抽运基于周期性极化铌酸锂(PPLN)晶体的单共振光学参量振荡器(SRO), 实验产生了宽调谐高功率连续单频红外激光。通过控制改变PPLN晶体的极化周期和温度, 连续单频信号光和闲频光波长分别可从1.45 μm调谐到1.79 μm和从2.62 μm调谐到3.99 μm。当抽运功率为15.5 W时, 1.52 μm信号光和3.53 μm闲频光的最大输出功率分别为5.1 W和2.1 W, 光光转换效率达46.5%。当SRO自由运转时, 信号光和闲频光在4 h内实测的功率波动分别小于±2.77%和±2.79%, 同时信号光在4 h内实测的频率漂移小于±45 MHz。

A singly resonant optical parametric oscillator (SRO) is built up based on periodically poled lithium niobate (PPLN) crystal pumped by a self-made high power and continuous-wave (CW) single-frequency 1.06 μm laser. A broadly tunable and high power CW single-frequency laser source in the infrared is obtained and the signal and idler can be tuned from 1.45 μm to 1.79 μm and from 2.62 μm to 3.99 μm by controlling the polarization period and temperature of PPLN crystal, respectively. The measured maximum output powers of the signal (1.52 μm) and idler (3.53 μm) are 5.1 W and 2.1 W, respectively, at a pump power of 15.5 W. The optical conversion efficient of the SRO is 46.5%. When the SRO is free running, the power fluctuation of the signal and idler are less than ±2.77% and ±2.79% for a given 4 h, respectively, and the frequency drift of the signal is less than ±45 MHz for the given 4 h.