Patent ID: 7804865
Filing Date: 2010-09-28
Classification: H01S

Abstract:
1. A monomode laser device comprising: an amplifying medium capable of generating a laser beam of fundamental wavelength; a birefringent non-linear medium with parallel faces for frequency doubling of the laser beam of fundamental wavelength so as to generate a laser beam of harmonic wavelength; and a polarizing medium for selecting a polarization of the laser beam of fundamental wavelength, said polarizing medium being such that the fundamental wavelength at its output remains parallel to the fundamental wavelength at its input, wherein the polarizing medium comprises an output face perpendicular to the fundamental wavelength exiting from said polarizing medium, wherein the amplifying medium, the birefringent non-linear medium and the polarizing medium are firmly attached so as to constitute a monolithic resonant cavity of said monomode laser, wherein the birefringent non-linear medium is constituted by a type I non-linear crystal the birefringent axes of which form non-zero angles modulo π/2 radians with respect to the polarization selected by the polarizing medium such that the device constitutes a Lyot filter, and wherein a birefringent crystal is joined to said non-linear crystal in such a way that the birefringence axes of this birefringent crystal remain parallel to those of said non-linear crystal.