High beam quality optical parametric oscillator

摘要

An optical parametric oscillator comprising two meniscus mirrors disposed on opposite sides of a nonlinear medium that forms a confocal unstable resonator. A reduced-to-practice embodiment uses concave-convex mirrors in a confocal arrangement disposed on opposite sides of a KTP crystal used as the nonlinear medium. The optical parametric oscillator and confocal unstable resonator of the present invention exhibits improved beam divergence angles.