Patent ID: 6483975
Filing Date: 2002-11-19
Classification: G02B

Abstract:
An optical fiber communications system, comprising:at least one source of optical energy; an optical fiber cable including at least one optical fiber coupled to the at least one source for transmitting optical energy from the source, wherein the optical fiber includes a doped core region having an index of refraction n1, a cladding region having an index of refraction n2, wherein 0.141âˆ’n2)/n2<0.31, a first region between the doped core region and the cladding region and adjacent the doped core region, the first region having an index of refraction n3, wherein âˆ’0.193âˆ’n2)/n2a second region between the doped core region and the cladding region and adjacent the first region, the second region having an index of refraction n4, wherein âˆ’0.204âˆ’n2)/n2at least one receiver coupled to the optical fiber for receiving optical energy from the source.