Abstract: An optical parametric oscillator or OPO (20) includes an elongated resonant cavity (22) for signal light, having a parametric gain medium (28) disposed therein for converting pump light to signal light. The resonant cavity has a output coupling device (26) at one end thereof and a Porro prism (24) at the opposite end thereof. The OPO includes an optical arrangement (30, 39 and 40) for directing pump light to make counterpropagating initial and return passes longitudinally through the gain medium at an angle (36) to the axis (23) of the resonant cavity.

Abstract: An eye-safe short pulse room-temperature solid state laser emitting at about 2.1 microns is optically pumped by diode lasers emitting at about 1.9 microns Absorption spectra of Ho ions in YAG (Yttrium Aluminum Garnet) and YLF (Yttrium Lithium Fluoride) host crystals are described. Optical pumping is performed by high-power diode lasers emitting at about 1.91 microns consisting of a GaInAsSb/AlGaAsSb quantum-well active region and AlGaAsSb cladding layers grown on GaSb substrates.

Abstract: A high power injection-locked laser system (10) is disclosed which includes master and slave lasers (12, 14) both of which are solid state lasers having continuous wave outputs. The slave laser has an output power at least ten times greater than the master laser. In the preferred embodiment, the slave laser is at least one-hundred times as powerful as the master laser. In accordance with the subject invention, a servo-loop control system is used to maintain the injection locked condition. A discriminant signal is generated that is indicative of drift in the slave laser cavity. The discriminant signal is used adjust the length of the slave laser cavity to maintain the locked condition.