Patent ID: 7903701
Filing Date: 2011-03-08
Classification: G02F,H01S

Abstract:
1. A method of intracavity generation of a second or higher order harmonic laser beam implemented for increased efficiency by recycling a second harmonic laser beam while maintaining beam quality of the higher order harmonic laser beam, comprising: providing a resonant laser cavity defined by first and second end mirrors and containing a gain medium; optically pumping the gain medium to generate a fundamental laser beam within the resonant laser cavity, the fundamental laser beam oscillating between the first and second end mirrors; positioning within the resonant laser cavity a second harmonic nonlinear medium to interact with the fundamental laser beam and thereby generate a second harmonic laser beam; positioning in optical association with the resonant laser cavity a higher order harmonic nonlinear medium to interact with the second harmonic laser beam and thereby generate a laser beam of higher order than the second order laser beam; positioning in optical association with the gain medium and the second harmonic nonlinear medium an optical energy coupler that is reflective of the fundamental laser beam and anti-reflective of the second harmonic laser beam, the unreflected second harmonic laser beam exiting the resonant laser cavity through the optical energy coupler as a residual second harmonic laser beam having a beam mode; and setting mode-matching optics in optical association with the optical energy coupler to reflect back into the resonant cavity the residual second harmonic laser beam for intracavity generation of the higher order laser beam, the mode-matching optics being prescribed and positioned relative to the optical energy coupler to establish for the reflected residual second harmonic laser beam a beam mode that substantially matches the beam mode of the residual second harmonic laser beam, thereby to increase higher order harmonic laser beam generation efficiency while maintaining the beam quality of the higher order harmonic laser beam.