Patent ID: 6856743
Filing Date: 2005-02-15
Classification: G02B

Abstract:
1. An optical waveguide fiber comprising: a central region extending radially outward from the centerline and having a positive relative refractive index percent, Δ a first annular region surrounding the central region and having a positive relative refractive index percent, Δ a second annular region surrounding the first annular region and having a negative relative refractive index percent, Δ an outer annular cladding region surrounding the second annular region and having a relative refractive index percent, Δ wherein the mode field diameter at 1550 nm is greater than 9 μm; wherein the inner radius of the second annular region, R wherein the outer radius of the second annular region, R wherein the optical fiber has an effective area of greater than about 60 μm