US4504297A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical fiber preform manufacturing method
Assignee: Nokia Bell Labs
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Filing: 1983-07-06
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Granted: 1985-03-12
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Expires: 2003-07-06
Abstract
Abstract The time required to collapse an OH-rich silica tube can be reduced significantly by subjecting the tube to a deuterium/hydrogen exchange prior to its collapse.
Inventors
- 👤 Sandra G. Kosinski
- 👤 Paul J. Lemaire
- 👤 Paul B. O'Connor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:46
CPC Classifications
C; C03; C03C; C03C13/00; C03C13/04; C03C13/045; C03C13/047; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/018; C03B37/01853; C03B37/01861; C03B37/01884; C03B37/01892; C03B2201/00; C03B2201/06; C03B2201/07; C03B2201/075; C03B2201/20; C03B2201/22; Y; Y10; Y10S; Y10S65/00; Y10S65/90
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
227 words
Method for manufacturing an optical fiber, the fiber having an operating wavelength and a loss at the operating wavelength, a core of diameter d, a first clad of outer diameter D surrounding the core, and a second clad surrounding the first clad, the material of the second clad derived from a pre-existing tube consisting substantially of silica having an initial OH-content greater than about 25 ppmw, the material of the core and the material of the first clad formed by means of a glass-forming reaction, the method for manufacturing the optical fiber comprising drawing the fiber from a glass body, to be termed a preform, the preform having been produced by a process comprising collapsing at least a part of a tubular body comprising the pre-existing tube, the preform being configured such that the fiber drawn therefrom has, at the operating wavelength, a substantially negligible loss due to OH diffused from the material of the pre-existing tube into the material formed by means of the glass-forming reaction, the method characterized in that at least some of the material of the pre-existing tube is subjected, prior to collapse of the tubular body, to a deuterium/hydrogen exchange treatment, such that the OH-content of the material of the part of the pre-existing tube is reduced from the initial OH-content by at least about 50% or 100 ppmw, whichever is less.
Claim 2
Dependent Claim
227 words
Method for manufacturing an optical fiber, the fiber having an operating wavelength and a loss at the operating wavelength, a core of diameter d, a first clad of outer diameter D surrounding the core, and a second clad surrounding the first clad, the material of the second clad derived from a pre-existing tube consisting substantially of silica having an initial OH-content greater than about 25 ppmw, the material of the core and the material of the first clad formed by means of a glass-forming reaction, the method for manufacturing the optical fiber comprising drawing the fiber from a glass body, to be termed a preform, the preform having been produced by a process comprising collapsing at least a part of a tubular body comprising the pre-existing tube, the preform being configured such that the fiber drawn therefrom has, at the operating wavelength, a substantially negligible loss due to OH diffused from the material of the pre-existing tube into the material formed by means of the glass-forming reaction, the method characterized in that at least some of the material of the pre-existing tube is subjected, prior to collapse of the tubular body, to a deuterium/hydrogen exchange treatment, such that the OH-content of the material of the part of the pre-existing tube is reduced from the initial OH-content by at least about 50% or 100 ppmw, whichever is less.
Claim 3
Dependent Claim
89 words
Method of claim 1, wherein the tubular body further comprises some reaction product of the glass-forming reaction, the reaction product having been deposited onto the interior surface of the pre-existing tube, the pre-existing tube to be referred to as the substrate tube, and the deuterium/hydrogen exchange treatment comprises maintaining, prior to deposition of the reaction product onto the substrate tube, at least part of the substrate tube at a temperature of at least 150° C. in an atmosphere having a deuterium partial pressure of at least about 10 Torr.
Claim 4
Dependent Claim
66 words
Method of claim 1, wherein the pre-existing tube, to be termed the sleeve tube, is collapsed around a preformed glass body consisting substantially of reaction product of the glass-forming reaction, and the deuterium/hydrogen exchange treatment comprises maintaining at least part of the sleeve tube at a temperature of at least 150° C. in an atmosphere having a deuterium partial pressure of at least about 10 Torr.
Claim 5
Dependent Claim
47 words
Method of claim 1, wherein the deuterium/hydrogen exchange treatment comprises maintaining at least part of the pre-existing tube at a temperature of at least about 500° C. for at least about 30 minutes in an atmosphere having a deuterium partial pressure of at least about 10 Torr.
Claim 6
Dependent Claim
20 words
Method of claim 4, wherein the deuterium/hydrogen exchange step results in substantially complete removal of OH from the pre-existing tube.
Claim 7
Dependent Claim
32 words
Method of claim 5, wherein the deuterium/hydrogen exchange treatment results in an OD concentration in the material of the pre-existing tube that is greater than the initial OH concentration in the material.
Claim 8
Dependent Claim
13 words
Method of claim 1, wherein the optical fiber is a single mode fiber.
Claim 9
Dependent Claim
13 words
Method of claim 7, wherein the fiber if a depressed index cladding fiber.
Claim 10
Dependent Claim
16 words
Method of claim 1, wherein the optical fiber has a ratio D/d greater than about 4.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-11 | 1988-09-10 | 1989-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-11 | 1992-09-10 | 1993-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-11 | 1996-09-10 | 1997-03-12 | $7700.00 | Window Closed / Lapsed |