Fig. 1. Schematic diagram of experimental setup

Fig. 2. Calculated and experimental results for different crystal lengths. (a) Frequency doubling efficiency at different crystal lengths varies with wavelength; (b) curves of frequency doubling efficiency and green light power as functions of fundamental frequency light power (inset is a picture of power meter head at 610 W under green light)

Fig. 3. Beam quality of green laser at 610 W