A 31.5 W Solar-Pumped Nd: YAG Solid-State Laser

A solar directly pumped Nd: YAG solid-state laser with low threshold power is designed, in which Fresnel lens with the surface of 1.03 m² and focal length of 1.2 m is used as the primary solar radiation concentrator, and gold-plated conical cavity with a liquid light-guide lens is used as the secondary concentrator. The continuous and stable 1064 nm laser is obtained by end-side pumping Nd: YAG grooved rod with diameter of 5 mm and length of 75 mm, under combined action of liquid light guide lens and the gilded taper cavity. Theoretical model is established by optical design software ZEMAX and laser resonator simulation software LASCAD, experimental results are verified, and system design is optimized by numerical simulation. The experimental results show that output power of the laser pumped Nd: YAG solid-state laser is highest 31.5 W, laser collection efficiency is 30.58 W/m², laser threshold power of is 102 W and slope efficiency is 4.25%. The energy conversion efficiency from solar radiation to laser is 3.2%.