Patent ID: 7322704
Filing Date: 2008-01-29
Classification: G03B,H01S,H04N

Abstract:
1. A surface-emitting extended cavity laser with intracavity frequency doubling in which output power at a frequency-doubled frequency decreases rapidly with intracavity loss exceeding about 1% per pass, comprising: a surface emitting laser gain element generating optical gain in a band of wavelengths of at least several nanonmeters about a fundamental wavelength, said fundamental wavelength having a corresponding fundamental frequency; an output coupler spaced apart from said laser gain element to form an extended cavity, said output coupler having a high reflectivity for light at said fundamental frequency; a nonlinear crystal disposed in said extended cavity to frequency double light at said fundamental frequency circulating within said extended cavity, said nonlinear crystal having a bandwidth for efficient frequency doubling of about one nanometer or less and a nonlinear dependence of the frequency doubled output power on the intensity of light at said fundamental frequency; and a thin film interference filter to stabilize the frequency of output light, said thin film interference filter disposed in said extended cavity and operative as a notch filter about the fundamental frequency with a bandwidth of less one nanometer and an optical loss no more than 1% per pass for light at said fundamental frequency.