Patent ID: 7426327

Claim:
An optical waveguide fiber comprising a central core region, a zero-dispersion wavelength less than 1450 nm, a dispersion slope at a wavelength of 1550 of less than 0.06 ps/nm 2 /km, and an attenuation at a wavelength of 1550 nm less than 0.190 dB/km, wherein the central core region comprises a central portion and an outer portion surrounding and directly adjacent the central portion, and the central portion extends radially outwardly from the centerline to a central portion outer radius, R 0 , and has a relative refractive index percent, Δ 0 %(r) with a maximum relative refractive index percent, Δ 0MAX ; wherein the outer portion extends radially outwardly from the central region to a core radius, R 1 , the outer portion having a relative refractive index percent, Δ 1 %(r) with a maximum relative refractive index percent, Δ 1MAX , wherein Δ 1MAX is non-positive.