Developing the thermal-lens-insensitive cavity for high-power passively Q-switched Raman yellow lasers

A thermal-lens-insensitive cavity is developed to attain a high-power passively Q-switched yellow laser with a pulse energy of 0.13 mJ, a pulse width of 0.76 ns, and a repetition rate of up to 20 kHz. The optimal geometric lengths for the cavity configuration are analytically derived. With the optimal configuration, the developed lens resonator is confirmed to simultaneously satisfy the excellent passive <i>Q</i> switching and the mode-size matching. Under the optimal condition, the optical-to-optical conversion efficiency is up to 16.5%.