Patent ID: 7254305

Claim:
An optical waveguide fiber comprising: a central segment extending radially outwardly from a centerline to a radius R 1 and having a positive relative refractive index percent, Δ 1 (r) in %, wherein the central segment has a maximum relative refractive index percent, Δ 1MAX ; an intermediate annular segment surrounding and directly adjacent to the central segment; and an outer annular segment surrounding and directly adjacent to the intermediate annular segment and extending to a radius R 3 and having a negative relative refractive index percent, Δ 3 (r) in %, with a minimum relative refractive index percent, Δ 3MIN , less than −0.1%; and an outer annular cladding surrounding and directly adjacent to the outer annular segment; wherein the relative refractive index of the optical fiber provides a dispersion slope of less than 0.07 ps/nm 2 /km at a wavelength of 1550 nm, a zero-dispersion wavelength of less than 1350 nm, and an attenuation of less than 0.20 dB/km at a wavelength of 1550 nm.