High efficiency Nd:YVO₄/LBO critical phase matching green laser

A high efficiency, composite and air cooling LD end-pumped Nd:YVO4, acousto-optic Q-switched, and LBO(critical phase matching) intracavity doubled all-solid-state green laser is reported. By analyzing the absorption characteristics, with different polarized light pump, the uniformity of the crystal absorption could be significantly improved when the gain medium was pumped with partially polarized light. The fundamental wave distortion could be improved and the conversion efficiency could be enhanced. When the incident pump power was 33 W, the repetition rate of the AO-Q switch is 20 kHz, a 1064 nm fundamental frequency laser with an output power of 15 W and a pulse width of 23.96 ns was obtained. The output power of 532 nm green laser was 11.2 W. The optical to optical conversion efficiency from diode to green and from IR to green laser were about 34% and 74.6%. The output power instability was 0.512 2% at the output power of 10 W, The M2 beam quality factor was 1.2 in the horizontal direction and 1.1 in the vertical direction .