中波红外3~5 μm波段以及长波红外8~12 μm波段的激光处于大气传输窗口, 在激光成像、环境监测、激光雷达、激光医疗、化学遥感和红外对抗等领域有着非常广阔的应用前景。基于非线性光学晶体, 采用光学非线性频率变换技术在实现中长波红外固体激光输出方面具有明显的技术优势。该方法激光器结构简单, 且晶体本身并不参与能量交换, 因而没有量子亏损, 从而产热很少。同时具有单色性好、宽调谐、高功率等优点。本文针对常用以及新型非线性光学晶体, 对其应用于中长波红外固体激光器的研究进展做了详细的总结。

3-5 μm and 8-12 μm infrared lasers are located in the atmospheric transmission window, which have broad applications in laser imaging, environmental monitoring, lidar, laser medicine, chemical remote sensing, and Infrared countermeasure. Based on the nonlinear optical crystals, optical nonlinear frequency conversion technology has obvious advantages in realization of mid- and long-ware infrared solid-state lasers output. The structure of the laser is simple, and the crystal itself are not involved in the progress of exchange of energy, so there is no quantum defect and little heat production, leading to a low generation of heat. At the same time, it has the advantages of good monochromatic, wide tuning wavelength range and high output power. This paper reviews the research progress of the applications of nonlinear optical crystals in mid-and long-wave infrared solid-state laser.