Patent ID: 8055111

Claim:
A dispersion-shifted optical fiber (NZDSF), comprising from its center towards its periphery, a central core, an inner cladding comprising at least three zones, and an optical cladding, the central core having a radius (r 1 ) and an index difference (Dn 1 ) with the optical cladding, the inner cladding comprising from the central core towards the optical cladding: an intermediate cladding having a radius (r 2 ) and index difference (Dn 2 ) with the optical cladding; a ring having a radius (r 3 ) and an index difference (Dn 3 ) with the optical cladding; and a buried trench having a radius (r tr ), a width (W tr ) of between 2.5 μm and 5.5 μm, and an index difference (Dn t ) with the optical cladding of between −5×10 −3 and −15×10 −3 ; wherein the optical fiber possesses: Rayleigh scattering losses of less than or equal to 0.164 dB/km at a wavelength of 1550 nm; bending losses of less than 0.5 dB/turn for a bending radius of 16 millimeters at a wavelength of 1550 nm; and bending losses of less than 0.5 dB/100 turns for a bending radius of 30 millimeters at a wavelength of 1625 nm.