中红外全固态光参变振荡器，由于其宽的调谐范围、低阈值、高效率、高重复率及小型化的优点，在光电对抗、激光雷达、激光测距、光谱测量以及在环境监测等领域都有广泛的应用前景。全固态中红外激光器一直是激光技术研究的热点。介绍了基于双折射相位匹配晶体(如砷酸钛氧钾和磷酸钛氧钾)和准相位匹配晶体(如周期极化磷酸钛氧钾、周期极化砷酸钛氧钾和周期极化铌酸锂)的中红外内腔单谐振光参变振荡器的国内外一些最新的研究进展，并对其发展趋势进行了展望。

Due to advantages of wide tuning range, low threshold, high efficiency, high repetition rate and miniaturization, mid-infrared all-solid-state optical parametric oscillators(OPO)are wide spread in optoelectronic countermeasures, laser radar, laser ranging, spectral measurements and environmental monitoring. In recent years there has been increasing interest in the mid-infrared OPOs. The research and progress of middle-infrared intracarity single resonant OPO based on birefringent phase-matching crystals(such as KTiOASO4(KTA), KTiOPO4(KTP)) and quasi-phase matching crystals (such as periodically poled KTiOPO4(PPKTP), peridodically poled KTiOASO4(PPKTA), periodically poled LiNbO3(PPLN)) were introduced. The development trend of intracarity single resonant OPO was also discussed.