Low loss optical fibers with fluorine and chlorine codoped core regions

Patent metadata

Field	Value
Publication number	US-10150695-B2
Application number	US-201715689648-A
Country	US
Kind code	B2
Filing date	Aug 29, 2017
Priority date	Apr 15, 2015
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

A co-doped optical fiber is provided having an attenuation of less than about 0.17 dB/km at a wavelength of 1550 nm. The fiber includes a core region in the fiber having a graded refractive index profile with an alpha of greater than 5. The fiber also includes a first cladding region in the fiber that surrounds the core region. Further, the core region has a relative refractive index of about −0.10% to about +0.05% compared to pure silica. In addition, the core region includes silica that is co-doped with chlorine at about 1.2% or greater by weight and fluorine between about 0.1% and about 1% by weight.

First claim

What is claimed is:

1. An optical fiber, comprising:
a fiber having an attenuation of less than about 0.17 dB/km at a wavelength of 1550 nm, the fiber comprising:
a core region in the fiber having a graded refractive index profile with an alpha of greater than 0.5; and
a first cladding region in the fiber that surrounds the core region,
wherein the core region comprises silica co-doped with chlorine at about 1.2% or greater by weight and fluorine between about 0.1% and about 1% by weight.

2. The fiber according to claim 1 , wherein the core region has a relative refractive index, Δ 1 , of about −0.20% to about +0.1% compared to pure silica.

3. The fiber according to claim 1 , wherein the first cladding region comprises (a) an inner cladding region that surrounds the core region and has a relative refractive index, Δ 2 , and (b) a depressed cladding region that surrounds the inner cladding region and has a relative refractive index, Δ 3 ; the core region has a relative refractive index, Δ 1 ; and Δ 1 ≥Δ 2 >Δ 3 .

4. The fiber according to claim 3 , wherein the first cladding region further comprises an outer cladding region having a relative refractive index, Δ 4 , and further wherein Δ 4 >Δ 3 .

5. The fiber according to claim 1 , wherein the core region comprises silica co-doped with chlorine and fluorine, the chlorine at about 2.5% or greater by weight.

6. The fiber according to claim 1 , wherein the core region comprises silica co-doped with fluorine and chlorine such that the sum of the fluorine and chlorine in weight percent divided by the fluorine in weight percent is greater than a factor about 1.5.

7. The fiber according to claim 1 , wherein the fiber further comprises a mode field diameter (MFD) from about 8.2 μm to about 9.5 μm at 1310 nm.

8. The fiber according to claim 7 , wherein the fiber further comprises a macrobend loss at 1550 nm of ≤1.5 dB/turn on a 20 mm diameter mandrel.

9. The fiber according to claim 4 , wherein the viscosity at 1650° C. of the outer cladding region is greater than the viscosity at 1650° C. of at least one of the core region, the inner cladding region and the depressed cladding region.

10. The fiber according to claim 4 , wherein the difference in viscosity at 1650° C. of the outer cladding region is ≥1×10 6 Poise and ≤1.6×10 8 Poise of the viscosity at 1650° C. of at least one of the core region, the inner cladding region and the depressed cladding region.

11. The fiber according to claim 4 , wherein the ratio in viscosity at 1650° C. of the outer cladding region is ≥1.1 to the viscosity at 1650° C. of at least one of the core region, the inner cladding region and the depressed cladding region.

12. The fiber according to claim 4 , wherein the ratio in viscosity at 1650° C. of the outer cladding region is ≥1.1 to the viscosity at 1650° C. of the core region.

13. The fiber according to claim 1 , wherein the first cladding region comprises (a) an inner cladding region that surrounds the core region and has a relative refractive index, Δ 2 , and (b) an outer cladding region that surrounds the inner cladding region, has a relative refractive index, Δ 5 and comprises undoped silica or silicon oxynitride; the core region has a relative refractive index, Δ 1 ; Δ 1 ≥Δ 2 ; and Δ 5 ; >Δ 2 .

14. The fiber according to claim 13 , wherein the fiber further comprises a 22 m cable cutoff of ≤1260 nm.

15. The fiber according to claim 13 , wherein the fiber further comprises a zero dispersion wavelength between 1300 nm and 1324 nm.

16. An optical fiber, comprising:
a fiber having an attenuation of less than about 0.17 dB/km at a wavelength of 1550 nm, the fiber comprising:
a core region in the fiber having a graded refractive index profile with an alpha of greater than 0.5, the core region further comprises a relative refractive index, Δ 1 , of about −0.20% to about +0.1% compared to pure silica; and
a first cladding region in the fiber that surrounds the core region,
wherein the core region comprises silica co-doped with fluorine and chlorine, and
further wherein the fiber comprises a mode field diameter (MFD) from about 8.2 μm to about 9.5 μm at 1310 nm.

17. The fiber according to claim 16 , wherein the fiber further comprises a macrobend loss at 1550 nm of ≤1.5 dB/turn on a 20 mm diameter mandrel.

18. The fiber according to claim 16 , wherein the fiber further comprises a macrobend loss at 1550 nm of ≤5 dB/turn on a 15 mm diameter mandrel.

19. The fiber according to claim 16 , wherein the fiber further comprises a macrobend loss at 1550 nm of ≤0.025 dB/turn on a 30 mm diameter mandrel.

20. The fiber according to claim 16 , wherein the fiber further comprises a macrobend loss at 1550 nm of ≤0.01 dB/turn on a 30 mm diameter mandrel.

21. The fiber according to claim 16 , wherein the fiber further comprises a macrobend loss at 1550 run of ≤0.005 dB/turn on a 30 mm diameter mandrel.

22. The fiber according to claim 16 , wherein the fiber further comprises a 22 m cable cutoff of ≤1260 nm.

23. The fiber according to claim 16 , wherein the fiber further comprises a zero dispersion wavelength between 1300 nm and 1324 nm.

24. An optical fiber, comprising:
a fiber having an attenuation of less than about 0.17 dB/km at a wavelength of 1550 nm, the fiber comprising:
a core region in the fiber having a graded refractive index profile with an alpha of greater than 0.5, the core region further comprises a relative refractive index, Δ 1 , of about −0.20% to about +0.1% compared to pure silica; and
a first cladding region in the fiber that surrounds the core region,
wherein the core region comprises silica co-doped with fluorine and chlorine, and
further wherein the fiber comprises a mode field diameter (MFD) from about 9.0 μm to about 14 μm at 1550 nm.

25. The fiber according to claim 24 , wherein the fiber further comprises a 22 μm cable cutoff of ≤1260 nm.

26. The fiber according to claim 24 , wherein the fiber further comprises a macrobend loss at 1550 nm of ≤1.5 dB/turn on a 20 mm diameter mandrel.

27. The fiber according to claim 24 , wherein the fiber further comprises a macrobend loss at 1550 nm of ≤0.5 dB/turn on a 20 mm diameter mandrel.

28. The fiber according to claim 24 , wherein the fiber further comprises a dispersion at 1550 nm of less than or equal to about 22 ps/nm/km.

Assignees

• Corning Inc

Inventors

• Bookbinder Dana Craig
• Li Ming-Jun
• Tandon Pushkar

Classifications

• C03B2201/12

  doped with fluorine (C03B2201/14 takes precedence) · CPC title

• C03C3/06

  with more than 90% silica by weight, e.g. quartz {(C03C3/045 takes precedence)} · CPC title

• C03B2201/20

  doped with non-metals other than boron or fluorine · CPC title

• C03C13/046 Primary

  Multicomponent glass compositions · CPC title

• C03B2203/23

  Double or multiple optical cladding profiles · CPC title