Patent ID: 7050476

Claim:
A resonator for a solid-state planar waveguide laser, the resonator comprising two concave mirrors, one disposed on either side of a multi-mode planar waveguide gain section of the laser, the planar waveguide gain section comprising a solid-state waveguide core sandwiched between an upper cladding layer and a lower cladding layer, wherein the two mirrors are formed and arranged relative to the planar waveguide gain section: so as to provide a substantially confocal negative branch unstable resonator in a lateral direction; so as to provide a low loss waveguide resonator in a transverse direction; and so that a focal point of the negative branch unstable resonator is disposed outside the planar waveguide gain section; and wherein a first one of the mirrors is an output mirror configured to couple light out of the resonator, and the position and radius of curvature of said output mirror corresponds substantially to the Degnan and Hall Case II configuration.