Multiband optical fiber

Abstract

An optical waveguide fiber having a core surrounded by a cladding. The core may have only a central segment, or a central segment and an annular segment surrounding the central segment. The central segment has a positive relative refractive index profile. The annular segment has a negative relative refractive index profile. The relative refractive index of the optical fiber provides an LP02 cable cutoff less than 850 nm and an LP21 cable cutoff less than 850 nm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-2 show refractive index profiles corresponding to a first set of embodiments of an optical waveguide fiber as disclosed herein.

FIGS. 3-4 shows a refractive index profile corresponding to a second set of embodiments of an optical waveguide fiber as disclosed herein.

FIG. 5 shows bandwidth versus wavelength for the optical fiber profiles of FIGS. 1-4, labeled 1-4 respectively.

FIG. 6 is a schematic representation of an optical waveguide fiber as disclosed herein having a core and a clad layer directly adjacent and surrounding the core, wherein the core comprises two core segments.

FIG. 7 is a schematic illustration of a fiber optic communication system comprising an optical fiber as disclosed herein.

FIG. 8 is a schematic illustration of another optical fiber communication system which comprises an optical fiber disclosed herein.

Claims

1. An optical waveguide fiber comprising: a core comprising a central core segment extending radially outwardly from a centerline to a radius R1 and having a positive relative refractive index percent profile, Δ1(r) in %, wherein the central core segment comprises a maximum relative refractive index percent, ΔMAX; andan outer annular cladding surrounding the core and comprising a relative refractive index percent, Δc (r) in %;wherein ΔMAX>0;wherein the relative refractive index of the optical fiber provides an LP02 cable cutoff less than 850 nm and an LP21 cable cutoff less than 850 nm.

2. The optical fiber of claim 1 wherein the relative refractive index of the optical fiber provides an LP11 cable cutoff less than 1260 nm.

3. The optical fiber of claim 1 wherein the relative refractive index of the optical fiber provides a bandwidth greater than 10 GHz-km at all wavelengths in a wavelength range having a rangewidth of at least 10 nm, and wherein the wavelength range lies between 830 and 870 nm.

4. The optical fiber of claim 1 wherein the outer annular cladding is directly adjacent the central core segment.

5. The optical fiber of claim 1 wherein the core further comprises an annular segment surrounding and directly adjacent to the central core region and extending to a radius R2 and having a negative relative refractive index percent profile, Δ2(r) in %, with a minimum relative refractive index percent, Δ2MIN.

6. The optical fiber of claim 1 wherein the relative refractive index of the optical fiber provides a dispersion at 1550 nm between 16 and 20 ps/nm/km.

7. The optical fiber of claim 1 wherein the relative refractive index of the optical fiber provides a zero dispersion between 1280 and 1320 nm.

8. The optical fiber of claim 1 wherein the relative refractive index of the optical fiber provides an absolute magnitude of dispersion at 1310 nm less than 5 ps/nm/km.

9. The optical fiber of claim 1 wherein the bandwidth is greater than 10 GHz-km at all wavelengths between 825 and 875 nm.

10. The optical fiber of claim 1 wherein the bandwidth is greater than 10 GHz-km at 850 nm.

11. The optical fiber of claim 1 wherein Δ1MAX is between 0.35 and 0.45%.

12. The optical fiber of claim 1 wherein Δ2MIN is between −0.05 and −0.15%.

13. The optical fiber of claim 1 wherein the central core segment comprises an alpha region having an alpha between 2.0 and 2.9.

14. The optical fiber of claim 13 wherein the central core segment further comprises a central peak region disposed between the centerline and the alpha region, wherein the central peak region contains the maximum relative refractive index of the optical fiber.

15. The optical fiber of claim 13 wherein the central core segment further comprises a central peak region, wherein ΔMAX is disposed in the central peak region, and the alpha region comprises a maximum relative refractive index percent, ΔBMAX, wherein Δ1MAX−ΔBMAX, is between 0.03% and 0.08%.

16. The optical fiber of claim 1 wherein the optical fiber has an effective area of greater than about 60 μm2 at 1550 nm.

17. The optical fiber of claim 1 wherein the optical fiber has an attenuation less than 0.20 dB/km at 1550 nm.

18. The optical fiber of claim 1 wherein the pin array loss of the optical fiber is less than 10 dB.

19. The optical fiber of claim 1 wherein the optical fiber has an attenuation of less than 0.4 dB/km at a wavelength of about 1310 nm.

20. The optical fiber of claim 1 wherein the optical fiber has an attenuation at 1380 nm not more than 0.1 dB/km greater than an attenuation at 1310 nm.