Continuously adjustable-pulse-width electro-optically Q-switched laser with Nd:YVO₄/Nd:YAG dual crystals

This paper reports an electro-optically Q-switched Nd:YVO₄/Nd:YAG laser with continuously adjustable pulse width. The tunability of the pulse width is realized by adjusting the pump power on the two crystals. We establish a dual-crystal pulse width adjustment theoretical model. That is, by controlling the change rate of the inverted population number densities of the dual crystals, the time distribution of the photon number density can be altered. Maintaining the laser average power at 3 W, the pulse width adjustment ranges were 20.8-52.2 ns corresponding to 5.7-14.4 kW peak power at 10 kHz, and 35.4-93.6 ns corresponding to 1.6-4.2 kW peak power at 20 kHz. Without changing the mechanical structure and other main parameters of the laser, this pulse width adjustment method is simple and stable.