Patent US4396409A successfully refreshed from Google Patents.
US4396409A
Expired / Lapsed
US
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Method of improving fatigue resistance of optical fibers
Assignee: Corning Glass Works
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Filing: 1981-12-11
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Granted: 1983-08-02
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Expires: 2001-12-11
Abstract
Abstract Disclosed are a method and apparatus for improving the fatigue characteristics of a glass optical waveguide fiber. After the fiber is drawn and before it is provided with a protective coating it is heated to a temperature within the annealing temperature range. A filtered gas may be flowed over the fiber during the step of heating.
Inventors
- 👤 Alan C. Bailey
- 👤 Robert D. Maurer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:57
CPC Classifications
C; C03; C03C; C03C25/00; C03C25/10; C03C25/104; C03B; C03B37/00; C03B37/10; C03B37/14; C03B37/15
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
101 words
In the method of forming a low loss optical waveguide fiber comprising the steps of drawing from a source of molten non-devitrifiable glass a fiber having a core and an outer cladding layer, said fiber having a hydroxyl ion content less than 100 ppm, and applying a protective coating of plastic material to said fiber, the improvement comprising heating said fiber, while said fiber is being drawn and prior to applying a coating thereto, to a temperature within the annealing temperature range of the cladding glass to improve the fatigue characteristics of said fiber without devitrifying said core or cladding glass.
Claim 2
Dependent Claim
101 words
In the method of forming a low loss optical waveguide fiber comprising the steps of drawing from a source of molten non-devitrifiable glass a fiber having a core and an outer cladding layer, said fiber having a hydroxyl ion content less than 100 ppm, and applying a protective coating of plastic material to said fiber, the improvement comprising heating said fiber, while said fiber is being drawn and prior to applying a coating thereto, to a temperature within the annealing temperature range of the cladding glass to improve the fatigue characteristics of said fiber without devitrifying said core or cladding glass.
Claim 3
Dependent Claim
24 words
A method in accordance with claim 1 further comprising the step of flowing a filtered gas over said fiber during the step of heating.
Claim 4
Dependent Claim
27 words
A method in accordance with claim 2 wherein, during the step of heating said fiber, the temperature of said fiber is between 900° C. and 1300° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-01 | 1987-01-31 | 1987-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-01 | 1991-01-31 | 1991-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-01 | 1995-01-31 | 1995-08-02 | $7700.00 | Window Closed / Lapsed |