Optimization of a rotary Q-switched Er:YAG laser

An erbium:yttrium–aluminum–garnet Er:YAG (λ=2.94 μ m ) rotary Q-switched laser was optimized for long-term stability and reliability, maximum output energy, and TEM oo mode quality. This optimization was achieved employing a close-coupled BaSO 4 diffuse reflector pump chamber and a dehumidifying assembly and an ultra-dry-air purge system. The performance and efficiency of the Er:YAG laser were further enhanced by appropriate variations in the coolant temperature, rotational frequency of the Q-switch mirror, and pulse repetition rate. These improvements should facilitate the implementation of rotating mirror Q-switched Er:YAG lasers in various laser photoablation and depth-profiling applications.