Thermal lens effect is a very important factor in designing stable resonators for high-power solid-state laser pumped by laser diodes. In a symmetric plane-parallel resonator , if the thermal lens of the laser crystal is close to a thin lens, according to the theory of transfer matrix we can get that there is a critical hollow point where the resonator changes from stable region to unstable state, then back to stable region. So we can measure the ultrashort thermal focal length of high-power solid-state laser based on this fact. We used this method to measure the ultrashort thermal focal length of a 100W magnitude Nd:YAG laser. The experimental results have shown this is a simple and effective technique.

Date Published: 5 September 2002
PDF: 4 pages
Proc. SPIE 4914, High-Power Lasers and Applications II, (5 September 2002); doi: 10.1117/12.481758

Published in SPIE Proceedings Vol. 4914:
High-Power Lasers and Applications II
Dianyuan Fan; Keith A. Truesdell; Koji Yasui, Editor(s)