Patent ID: 6272155
Filing Date: 2001-08-07
Classification: G02B,H01S

Abstract:
A laser apparatus for producing an output laser beam, wherein:said laser apparatus comprising:a fiber bundle in which in which one ends of a plurality of optical fibers are bundled as a bundled portion, said optical fibers including cores, respectively, each of said cores including a laser active material which produces a laser beam propagated through each of said cores towards said one end of said optical fibers, said fiber bundle outputting the laser beams from said one ends of the optical fibers collectively as said output laser beam; andexciting means for exciting said laser active material of each of said cores to make said laser active material of each of said cores produce said laser beam;said fiber bundle comprising in said bundled portion:a clad having a refractive index less than that of each of said cores and surrounding said cores so that said cores are positioned near to each other with a minimum distance left between two adjacent ones of said cores, said minimum distance being decided so that transverse modes of the laser beams propagated through said two adjacent ones of the cores do not affect each other;different ends of said fibers being kept separated as a separated portion without being bundled in said fiber bundle;said fiber bundle comprising in said separated portion:first clads, each of which has a first refractive index less than that of each of said cores and surrounds each of said cores; andsecond clads, each of which has a second refractive index less than that of each of said first clads and surrounds each of said first clads.