# US 2017/0285259 A1 · Optical fiber preform, optical fiber, and method of manufacturing optical fiber

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2017/0285259 A1
- Document ID: US20170285259A1
- Status: Published application
- Kind: A1
- Application number: 15/506,873
- Filed: 2016-06-10
- Published: 2017-10-05
- Earliest claimed: 2015-07-15
- Assignees: Fujikura Ltd.
- Applicants: Fujikura Ltd.
- Inventors: Katsubumi Nagasu
- Web page: https://patentgrep.com/patent/US20170285259A1

## CPC

- G02B 6/02395: {Glass optical fibre with a protective coating, e.g. two layer polymer coating deposited directly on a silica cladding surface during fibre manufacture (G02B6/02052, G02B6/02057, G02B6/024, G02B6/032, G02B6/105, G02B6/14 take precedence; coating on fibre gratings G02B6/02104; multilayer core or cladding G02B6/036; reinforcing splice joints G02B6/2558; optical cables, i.e. comprising protective structures external to the protective coating such as a jacket or plural coated optical fibres G02B6/44; coating of glass to obtain optical fibres C03C25/104)}
- B32B 17/00: Layered products essentially comprising sheet glass, or glass, slag, or like fibres
- B32B 17/061: {of metal}
- B32B 17/10018: {comprising only one glass sheet}
- B32B 17/10137: {Chemical strengthening}
- C03B 37/01446: {Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering (C03B37/01853 takes precedence)}
- C03B 37/01453: {for doping the preform with flourine}
- C03B 37/018: by glass deposition on a glass substrate, e.g. by {inside-, modified-, plasma- or plasma modified-} chemical vapour deposition {[ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod} (C03B37/016 takes precedence; surface treatment of glass by coating with glass C03C17/02)
- C03B 37/025: from reheated softened tubes, rods, fibres or filaments {, e.g. drawing fibres from preforms (draw-down of tubes, rods or preforms to reduced diameter preforms C03B37/0124)}
- C03B 37/0253: {Controlling or regulating (for glass fibre manufacture in general C03B37/07)}
- C03C 3/06: with more than 90% silica by weight, e.g. quartz {(C03C3/045 takes precedence)}
- C03C 13/04: Fibre optics, e.g. core and clad fibre compositions (light guides G02B6/00)
- C03C 13/045: {Silica-containing oxide glass compositions}
- C03C 21/002: {to perform ion-exchange between alkali ions (C03C21/005 takes precedence)}
- G02B 6/02: Optical fibres with cladding {with or without a coating}
- G02B 6/102: {for infrared and ultraviolet radiation}
- C03B 2201/02: Pure silica glass, e.g. pure fused quartz
- C03B 2201/12: doped with fluorine (C03B2201/14 takes precedence)
- C03B 2201/20: doped with non-metals other than boron or fluorine
- C03B 2201/50: doped with alkali metals
- C03B 2203/24: Single mode [SM or monomode]
- C03C 2201/11: containing chlorine
- C03C 2201/12: containing fluorine (C03C2201/14 takes precedence)
- Y02P 40/57: Improving the yield, e-g- reduction of reject rates
- G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- C03B: MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03C: CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

An optical fiber preform includes: a core formed of silica glass which does not contain Ge, wherein the core has at least one of characteristics in spectrometry of (1) an absorption peak is present at a wavelength of 240 nm to 255 nm, and (2) a wavelength at which an ultraviolet transmittance is 50% or lower is longer than 170 nm.

## Claims

### Claim 1

An optical fiber preform comprising:
a core formed of silica glass which does not contain Ge,
wherein the core has at least one of characteristics in spectrometry of
(1) an absorption peak is present at a wavelength of 240 nm to 255 nm, and
(2) a wavelength at which an ultraviolet transmittance is 50% or lower is longer than 170 nm.

### Claim 2 (depends on 1)

The optical fiber preform according to claim 1,
wherein the core is formed of pure silica glass or pure silica glass including chlorine.

### Claim 3 (depends on 1)

The optical fiber preform according to claim 1, further comprising:
a cladding formed of silica glass doped with fluorine on an outer circumference of the core.

### Claim 4 (depends on 1)

An optical fiber that is obtained by drawing the optical fiber preform according to claim 1,
wherein loss obtained by subtracting loss by Rayleigh scattering and imperfection loss from a total loss is 0.03 dB/km or less at a wavelength of 1550 nm,
a total loss at a wavelength of 1550 nm is 0.175 dB/km or less, and
an increase in loss caused by an OH group after the optical fiber is exposed to hydrogen gas at room temperature and 0.01 atmospheric pressure is 0.05 dB/km or less at a wavelength of 1383 nm.

### Claim 5 (depends on 1)

A method of manufacturing an optical fiber comprising:
drawing the optical fiber preform according to claim 1.

### Claim 6 (depends on 5)

The method of manufacturing an optical fiber according to claim 5, further comprising:
checking that the optical fiber preform has at least one of the characteristics of (1) and (2).