US4526599A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical fiber fabrication process
Assignee: Furukawa Electric North America Inc
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Filing: 1981-08-28
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Granted: 1985-07-02
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Expires: 2001-08-28
Abstract
Abstract A method of forming optical fibers with minimal contamination from ambient air is disclosed. In the inventive method a gas stream is introduced into a rotating structure by means of a rotating seal. The rotating seal comprises a rotating member seated within a stationary member. Counterflowing gases are flowed through the clearance region between the rotating and stationary members to prevent seepage of ambient air into the gas stream.
Inventors
- 👤 Robert L. Barns
- 👤 Arthur D. Pearson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:30
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/018; C03B37/01884
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
204 words
A method of forming an optical fiber, the method comprising flowing a first gas comprising glass precursor gas through a seal from a first stationary structure to a second structure rotating relative to the first structure, reacting in the second structure at least some of the glass precursor gas to form a glass, and forming the glass into an optical fiber, the fiber having an added loss at 1.39 microns of less than 2 db/km, the seal comprising a first member essentially rigidly connected to the first structure and a second member essentially rigidly connected to the second structure, the second member seated at least partially within the first member, with a clearance between the first member and the second member, thereby forming a clearance region through which ambient gas could enter to contaminate the first gas, the clearance region comprising a first and a second portion, the first portion being upstream of the second portion, relative to the flow of first gas, the clearance of the first portion being smaller than the clearance of the second portion, the method further comprising counterflowing noncontaminant second gas within the clearance region, whereby contamination of the first gas by the ambient gas can be substantially reduced.
Claim 2
Independent Claim
204 words
A method of forming an optical fiber, the method comprising flowing a first gas comprising glass precursor gas through a seal from a first stationary structure to a second structure rotating relative to the first structure, reacting in the second structure at least some of the glass precursor gas to form a glass, and forming the glass into an optical fiber, the fiber having an added loss at 1.39 microns of less than 2 db/km, the seal comprising a first member essentially rigidly connected to the first structure and a second member essentially rigidly connected to the second structure, the second member seated at least partially within the first member, with a clearance between the first member and the second member, thereby forming a clearance region through which ambient gas could enter to contaminate the first gas, the clearance region comprising a first and a second portion, the first portion being upstream of the second portion, relative to the flow of first gas, the clearance of the first portion being smaller than the clearance of the second portion, the method further comprising counterflowing noncontaminant second gas within the clearance region, whereby contamination of the first gas by the ambient gas can be substantially reduced.
Claim 3
Dependent Claim
26 words
The method of claim 1 further comprising forming the glass into an optical fiber having an added loss at 1.39 microns of less than 1.4 dB/km.
Claim 4
Dependent Claim
25 words
The method of claim 2 wherein the glass precursor gas comprises gas selected from the class consisting of silicon-containing gases, germanium-containing gases, and phosphorus-containing gases.
Claim 5
Dependent Claim
19 words
The method of claim 2 wherein the stationary structure is a gas bearing structure connected to a gas source.
Claim 6
Dependent Claim
19 words
The method of claim 4 wherein the second structure is a gas bearing structure connected to a reaction chamber.
Claim 7
Dependent Claim
13 words
The method of claim 5 wherein the reactant chamber is a glass tube.
Claim 8
Dependent Claim
25 words
The method of claim 6 wherein glass is deposited on the interior of the glass tube by means of the modified chemical vapor deposition process.
Claim 9
Independent Claim
22 words
The method of claims 1 or 7 wherein at least one of the first or second members comprises polytetrafluoroethylene or stainless steel.
Claim 10
Independent Claim
13 words
The method of claims 2 wherein the counterflowing second gas comprises reactant gases.
Claim 11
Dependent Claim
22 words
The method of claim 9 wherein the counterflowing gas comprises SiCl 4 , GeCl 4 , POCl 3 or O 2 .
References Cited (Backward Citations)
US28028A
Cited
USRE28028E
Cited
US4217027A
Cited
US4217027B1
Cited
US4140505A
Cited
US4203743A
Cited
US4317667A
Cited
US4347069A
Cited
US4389231A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-01 | 1988-12-31 | 1989-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-01 | 1992-12-31 | 1993-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-01 | 1996-12-31 | 1997-07-02 | $7700.00 | Window Closed / Lapsed |