Laser device and method of controlling Q-switched frequency converted laser, process and system using laser device

摘要

A harmonic Q switch laser device and its control method for obtaining a stable laser pulse while protecting a nonlinear optical crystal used for a wavelength conversion are presented. In this laser device, in a pause period of a laser train, a Q switch which is turned on makes the laser oscillates spuriously and continuously, and prevents a gain from accumulating in a gain medium Before a generation of a laser pulse, the Q switch is turned off for a specified period to raise the laser gain, so that a pulse of a specified magnitude is generated from the first shot when turning on the Q switch.