Abstract

Q-switched Nd:YAG lasers producing narrow-linewidth pump beams are imperative for efficient and reliable operation of diverse devices based on nonlinear optical conversion, such as harmonic generators, optical parametric oscillators etc. At present injection seeding¹ is considered to be the most advanced method to produce single-frequency oscillation in Q-switched solid-state lasers. However the injection seeded systems are rather complicated as they virtually employ two lasers: low power, frequency-stabilized. narrow-bandwidth oscillator and a regenerative amplifier. Alternative optical schemes based on ring resonator arrangement, being much simpler, sutler from relatively low pulse energy, usually 10...20 mJ. Besides some promising ring arrangements are poorly investigated with respect to pulse-to-pulse energy/shape stability.

© 1998 IEEE