Patent ID: 7593439

Claim:
A laser device comprising: an optical pumping means ( 10 ); an amplifying medium ( 2 ) excited by a laser beam ( 11 ) with a fundamental wavelength emitted by the optical pumping means, an output face ( 7 ) of the amplifying medium being cut according to the Brewster angle for said fundamental wavelength; a birefringent crystal ( 4 ) for frequency doubling, a crystalline axis “c” of said birefringent crystal forming an angle θ c , the angle θ c being not zero with respect to the orthogonal direction of the polarization of a fundamental wave of the laser beam, defined by the Brewster surface; and an isotropic medium ( 3 ) inserted between the output face ( 7 ) of the amplifying medium and an input face ( 8 ) of the birefringent crystal, wherein, a refractive index of the isotropic medium is within 10% of the refractive index of the birefringent crystal, the amplifying medium ( 2 ) and the birefringent crystal ( 4 ) are firmly attached to each other so as to constitute a monolithic resonant cavity, and the isotropic medium is made from potassium tantalate (KtaO 3 ).