Patent ID: 6801549
Filing Date: 2004-10-05
Classification: H01S

Abstract:
A clad-pumped, double clad, fiber laser, comprising:one or more cores disposed within a pump cladding; each doped with a rare earth lasing ion; each having an oblong cross section; there being either (a) a single core disposed at the center of said cladding or (b) a central core disposed at the center of said cladding and additional cores disposed outwardly of said central core, oriented in an array along a line inclusive of the center of said cladding with long axes of said central core and said additional cores perpendicular to said line and with an equal distance between the centers of adjacent cores; thereby to provide a linearly polarized output laser beam; each of said one or more cores having a mode discriminating core characteristic selected from (c) index of refraction, (d) gain, and (e) cross sectional dimension, said characteristic, in a fiber having a said single core, being greatest at the center of said single core and progressively lower toward the periphery of said single core, said characteristic of said central core, in a fiber having said additional cores, being greater than said characteristic of all others of said cores, said characteristic of each one of said other cores being lower than said characteristic of any of said cores that are closer to said central core than said one of said cores; thereby causing radiation in said cores to phase-lock and transfer laser power coherently into a linearly polarized, bright laser beam of the fundamental in-phase supermode from all higher order supermodes belonging to the same array structure.