Bromine-doped optical fiber

Patent metadata

Field	Value
Publication number	US-10884184-B2
Application number	US-201615378356-A
Country	US
Kind code	B2
Filing date	Dec 14, 2016
Priority date	Dec 22, 2015
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

Bromine doping of silica glass is demonstrated. Bromine doping can be achieved with SiBr4 as a precursor. Bromine doping can occur during heating, consolidation or sintering of a porous silica glass body. Doping concentrations of bromine increase with increasing pressure of the doping precursor and can be modeled with a power law equation in which doping concentration is proportional to the square root of the pressure of the doping precursor. Bromine is an updopant in silica and the relative refractive index of silica increases approximately linearly with doping concentration. Bromine can be used as a dopant for optical fibers and can be incorporated in the core and/or cladding regions. Core doping concentrations of bromine are sufficient to permit use of undoped silica as an inner cladding material in fibers having a trench in the refractive index profile. Co-doping of silica glass with bromine and chlorine is also demonstrated.

First claim

What is claimed is:

1. An optical fiber comprising:
a core, said core comprising silica glass doped with Br, said Br having a concentration in the range from 1.5 wt %-3.0 wt % and a relative refractive index at a wavelength of 1549 nm greater than or equal to 0.20% in said core; and
a cladding surrounding said core, said cladding comprising silica glass.

2. The optical fiber of claim 1 , further comprising Cl.

3. The optical fiber of claim 1 , wherein said cladding comprises Br.

4. The optical fiber of claim 1 , wherein said concentration of Br in said silica glass of said core is in the range from 1.75 wt %-2.75 wt %.

5. The optical fiber of claim 1 , wherein said core further comprises Cl.

6. The optical fiber of claim 1 , wherein said cladding includes an inner cladding and an outer cladding, said inner cladding having a lower relative refractive index than said outer cladding and said outer cladding having a lower relative refractive index than said core.

7. The optical fiber of claim 6 , wherein said inner cladding comprises silica glass doped with F.

8. The optical fiber of claim 7 , wherein the concentration of F in said silica glass of said inner cladding is in the range from 0.05 wt %-0.80 wt %.

9. The optical fiber of claim 6 , wherein said outer cladding comprises silica glass doped with Br.

10. The optical fiber of claim 1 , wherein said core has a relative refractive index in the range from 0.30%-0.45%.

11. The optical fiber of claim 6 , wherein said core has a relative refractive index in the range from 0.25%-0.50%.

12. The optical fiber of claim 11 , wherein said outer cladding has a relative refractive index in the range from 0.05%-0.20%.

13. The optical fiber of claim 1 , wherein said core has a relative refractive index Δ 1 in the range from 0.20% to 0.55%.

14. The optical fiber of claim 1 , wherein said silica glass of said cladding lacks Br.

15. The optical fiber of claim 1 , wherein said Br is a sole dopant in said core.

Assignees

• Corning Inc

Inventors

• Berkey George Edward
• Dawes Steven Bruce

Classifications

• C03B19/1453

  Thermal after-treatment of the shaped article, e.g. dehydrating, consolidating, sintering · CPC title

• C03C4/0092

  for glass with improved high visible transmittance, e.g. extra-clear glass · CPC title

• C03B37/01446

  Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering (C03B37/01853 takes precedence) · CPC title

• C03B37/01205

  starting from tubes, rods, fibres or filaments (C03B37/014 takes precedence) · CPC title

• G02B6/03622

  having 2 layers only · CPC title