Patent ID: 7283713

Claim:
An optical fiber comprising: a core disposed about a centerline; and a cladding surrounding the core; wherein the core and cladding define a relative refractive index profile; wherein the core comprises: a central segment extending radially outward from the centerline; a first annular segment surrounding the central segment; and a second annular segment surrounding the first annular segment; wherein the refractive index profile provides an effective area at 1550 nm less than or equal to 15.0 μm 2 , a dispersion at 1550 nm more negative than −150 ps/nm/km, and a kappa at 1550 nm greater than 100 nm, wherein kappa is dispersion at 1550 nm divided by dispersion slope at 1550 nm, and wherein the relative refractive index profile of the central segment has an alpha shape with an alpha greater than 10.