Patent ID: 7174078
Filing Date: 2007-02-06
Classification: G02B

Abstract:
1. An optical fiber for transmitting light, said optical fiber having an axial direction and a cross section perpendicular to said axial direction, said optical fiber comprising: (1) a first core region comprising a first core material having a refractive index N (2) a microstructured first cladding region surrounding the first core region, said first cladding region comprising a first cladding material and a plurality of spaced apart first cladding features or elements that are elongated in the fiber axial direction and disposed in the first cladding material, said first cladding material having a refractive index N (3) a second core region surrounding said first cladding region, said second core region comprising a second core material having a refractive index N (4) a second cladding region surrounding the second core region, said second cladding region comprising a second cladding material having a refractive index N the first core material, the first cladding material and the first cladding features, the second core material, and the second cladding material are selected and arranged so that N