Laser pulse control of a Q-switched Nd:YVO4 bounce geometry laser using a secondary cavity

Pulsed laser operation is desirable for a wide range of applications such as laser micromachining in industrial manufacturing and laser marking for product identification. In these cases it is beneficial to have flexibility in the parameters of the laser pulse to suit the specific application. This can include the ability to achieve a wide range of pulse repetition rates, with some applications requiring variation of laser pulse rate from high rate (multi-kHz) to low rate or even an off-state in a fast timescale. To generate ultrahigh pulse rates requires Q-switched lasers with ultrahigh gain, but problems can arise if the modulation element is insufficient to prevent laser action or hold-off lasing at low repetition rates. In these cases, lasing output can occur when it is not desired. In this work we present a novel method for pulse control in a high gain bounce amplifier Q-switched system by using a secondary cavity to clamp the gain and allow for clean single pulse operation from very high (800kHz) to very low (e.g.1kHz) repetition rates.