High average powers at 532 nm are of great interest for material processing applications because the absorption of metals and other materials increases with shorter wavelength. As the fundamental laser source we developed a Q-switched Nd:YAG oscillator-amplifier system with an average output power of 215 watts and a beam parameter product of less than 1 mm*mrad. The system operates with 100 Hz repetition rate and emits a burst of twenty Q-switch pulses during each flash-lamp pulse. The pulse duration of a single pulse increases from 100 to 200 nanoseconds with increasing pumping power. The high beam quality of the amplified beam is realized by a double-pass configuration of the amplifier with a phase conjugating SBS-cell. Additionally the thermally induced birefringence of the amplifiers is compensated for by a 90 degree-rotator between two identical amplifier rods. An output power of 164 W is frequency doubled in a KTP-crystal to 82 Watt average output power in the green which corresponds to 50% of doubling efficiency.

Date Published: 26 August 1996
PDF: 9 pages
Proc. SPIE 2788, High-Power Lasers: Gas and Solid State Lasers, (26 August 1996); doi: 10.1117/12.248615

Published in SPIE Proceedings Vol. 2788:
High-Power Lasers: Gas and Solid State Lasers
Tommaso Letardi; Horst Weber, Editor(s)