Lei Jiang

US Patent:

6597848, Jul 22, 2003

Filed:

Apr 26, 2000

Appl. No.:

09/558649

Inventors:

George E. Berkey - Pine City NY
Lei Jiang - San Diego CA
Dale R. Powers - Painted Post NY
V. Srikant - Ithaca NY

Assignee:

Corning Incorporated - Corning NY

International Classification:

G02B 618

US Classification:

385124

Abstract:

Disclosed is a dispersion compensating optical fiber that includes a core surrounded by a cladding layer of refractive index n. The core includes at least three radially adjacent regions, a central core region, a moat region having a refractive index n that is sufficiently lower than n such that -0. 4%, and a ring region. As the ring region exhibits sufficiently high refractive index at a sufficiently long distance from the outer edge of the moat region, the fiber can exhibit low values of negative dispersion slope at low values of negative dispersion and yet exhibit good bending loss. This ring region is also capable of imparting to the fiber a relatively high cutoff wavelength, so that the present invention is particularly well suited for use in L-band systems. A particularly suitable fiber has an index profile in which that part of the ring region at the transition between the moat and the ring region has a refractive index such that its delta value is close to zero. Also disclosed is a method of forming the fiber of the present invention.