Diode pumped solid state 532 nm green laser is widely required for many industrial, medical and scientific applications.
Among most of these applications, high power quasi-continuous-wave (QCW) green laser output is demanded. This can
be efficiently achieved through a diode-side-pumped acoustic-optic Q-switched Nd:YAG laser with an intracavity second
harmonic generation (SHG). In our experiment, LBO crystal is used for the second harmonic generation of
high-average-power lasers of near infrared (NIR) range, though its effective NLO coefficient d<sub>eff</sub> is relatively small. It is
because of its high damage threshold (greater than 2.5 GW/cm<sup>2</sup>), large acceptance angle, small walk-off angle, and the
nonhygroscopic characteristic. In this paper, we reported a high-repetition-rate high-power diode-side-pumped AO
Q-switched Nd:YAG 532 nm laser. A plane-plane cavity with two rods, two AO Q-switches and the type II critical
phase-matched LBO at room temperature were employed. Under the LD pump power of 480 W, 95.86 W at 1064 nm
wavelength was achieved when the repetition rate was 15 kHz, and the 532 nm average output power of 44.77 W was
obtained, with a pulse width of 111.7 ns, corresponding to an optical to optical conversion efficiency of 46.7% from 1064
nm to 532 nm. The 532 nm average output power was 40.10 W at a repetition rate of 10 kHz with a pulse width of 78.65
ns. The output characteristics of the SHG varying with the pumping current and the pulse repetition frequency (PRF) of
the laser were also investigated. Further improvement of the SHG is under study.