太阳光泵浦激光器直接利用太阳光作为泵浦源,实现了太阳光能量到激光能量的直接转化。设计了分腔水冷型金属锥形泵浦腔,以直径8 mm,长115 mm的Nd:YAG晶体棒作为激光工作物质,用有效面积1.03 m2菲涅尔透镜会聚太阳光,实验获得了23.7 W的稳定激光输出,斜效率为7.87%。通过对比实验,改进后的分腔水冷型太阳光泵浦激光器较原有锥形腔激光器有55.92%的激光输出功率提升。分别从侧面泵浦光在冷却水中的吸收损耗以及其耦合效率等方面对新型腔体结构进行了分析,证实了分腔水冷型腔体结构对侧面泵浦效率的提高,并提出了陶瓷漫反射材质的分腔水冷型激光腔的设计。

Solar pumped lasers directly convert sunlight into laser radiation. In this paper, we improve the configuration and structure of the hybrid pumping cavity adding a water-cooling system in the copper cavity. Output laser power is up to 23.7 W, using an Nd:YAG crystal rod with a diameter of 8 mm and a length of 115 mm as laser media, and a 7.87% slope efficiency is achieved. A Fresnel lens with a surface of 1.03 m2 is used as the primary solar light concentrator. It is shown through comparison experiments that the design of the new pumping cavity is an effective solution with a 55.92% increase in output power. We analyze the absorption loss and coupling efficiency of side-pumping light in the new cavity, and confirm that the new structure can improve the side-pumping efficiency. At the end of the article another design of composite cavity with ceramic material is put forward.