A High repetition rate, single-frequency Nd:YAG laser oscillator and its characteristics

Maruyama, Yoichiro; Oba, Masaki; Kato, Masaaki

JAERI-Tech 2002-004, 13 Pages, 2002/02

JAERI-Tech-2002-004.pdf:3.65MB

For the in-situ measurement of various substances in the atmosphere by using DIAL (Differential Absorption LIDAR) , a high repetition rate tunable laser is required to obtain data within a few seconds. As the pump source of the tunable laser, the performance of high repetition rate and high average power is indispensable. For the generation of high quality laser radiation, a laser oscillator with 1 kHz pulse repetition rate is made and seeded with very narrow linewidth single-longitudinal mode laser radiation from the outside of the oscillator cavity and its characteristics are studied. As the results, after the thermal equilibrium of the oscillator laser crystal, a single-longitudinal and near TEMoo transverse mode are realized at the pulse repetition rate between 0.5kHz and 1kHz. Single frequency operation is preserved by controlling the cavity length. The average output power of 3W (3mJ per pulse) is obtained. It is confirmed that this oscillator has enough performance as a oscillator of MOPA (Master Oscillator Power amplifier) system.