Patent ID: 7177340

Claim:
A laser apparatus, comprising: a laser diode having a reflective back facet and a front facet having a reflectance of less than 1% for emitting an optical beam at a fundamental frequency along an optical path; a collimating means for at least partially collimating the optical beam into an at least partially collimated beam along the optical path; a bulk transmission grating disposed in the optical path for receiving the at least partially collimated beam and for returning a portion of the at least partially collimated beam back toward the laser diode by means of diffraction, said portion being less than 10% in power so as to provide optical feedback into the laser diode between 1% and 5%, wherein the laser diode reflective back facet and the bulk transmission grating form an extended laser cavity, and wherein in operation, at least a substantial portion of the at least partially collimated beam is transmitted through the bulk transmission grating for producing a laser output beam propagating along the optical path.