Abstract: A laser resonator has a support disposed on its axis, to support an adjustable element rotatable with respect to the axis. An HR mirror reflects light, which passes through gain element means and partially through an OC mirror to provide a laser output. The adjustable element is fixed in rotation upon reaching a pre-selected laser output. One embodiment features a support comprising a recess in the substrate of the resonator, and one of the mirrors is formed on the spherically shaped bottom of the adjustable element. Alternatively, the adjustable element comprises a first Risley wedge pair rotatable within a V-block shaped support. Alternatively, a recess in the substrate supports the HR mirror and a Risley wedge pair. Both embodiments and their variations apply to two stage resonators, which then include a second support, appropriately placed wavelength shifting means and other optional optical elements.

Abstract: In an internal OPO, a substrate comprising a thin film lies along an axis and a first mirror reflects first wavelength light. A gain medium lases and polarizes light entering therein and a Q-switch attenuates and transmits first wavelength light. An HR/HT mirror passes first wavelength light and reflects a second wavelength light, and an OPO rod converts a portion of the first wavelength light into second wavelength light. An output coupler (OC) reflects first wavelength light and passes a portion of second wavelength light, the first wavelength reflecting between the first mirror, the OC and through the gain medium and the Q-switch. The second wavelength light reflects between the HR/HT mirror and OC and through the OPO rod. The invention applies to external OPO as well. The thin film reflects the light towards the gain medium, permitting a lower power lightsource and increasing the efficiency of the gain medium.