Patent ID: 6970484

Claim:
A laser formed by an optical resonator comprising: a) an electrically pumped semiconductor gain medium comprising a single-mode optical waveguide having first and second endfaces, where said first endface is an output coupler of said optical resonator, from which a beam with total power P a is emitted from said second endface; b) a lens which receives said emitted beam and transmits it to; c) an acousto-optic device which receives said transmitted beam, wherein said received beam is distorted and attenuated, but not frequency shifted, in the course of transmission through the acousto-optic device, and wherein the extent of the distortion and attenuation is dependent on the received beam wavelength and the RF frequency applied to the acousto-optic device; and d) a return mirror which reflects said non frequency-shifted beam back through said acousto-optic device and said lens; whereby said reflected beam impinges on said second endface with a total power P b , with a lesser optical power P 0 being launched into the gain medium waveguide, such that P 0 /P a has a maximum value at a wavelength Î» 0 where the total loss due to mode mismatching and attenuation in the external cavity is minimized, where Î» 0 is selected by said acousto-optic device in response to the RF frequency applied to said acousto-optic device, and wherein Î» 0 is the wavelength of laser emission from said first endface.