US3865564A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of glass fibers from preform by lasers
Assignee: AT&T Inc
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Filing: 1973-07-09
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Granted: 1975-02-11
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Expires: 1993-07-09
Abstract
Abstract Method and apparatus for drawing both clad and unclad fibers of indefinite length from glass preforms are described. A laser beam, generated by a laser operating in the far infrared, is used as a source of heat. In a particular embodiment, a beam of annular cross section is formed and directed substantially around the periphery of the preform.
Inventors
- 👤 Raymond Edward Jaeger
- 👤 Walter Logan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:11
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/025; C03B37/029; B; B23; B23K; B23K26/00; B23K26/02; B23K26/06; B23K26/064; B23K26/0643; B23K26/0648; B23K26/0652; B23K26/073; B23K26/0734; C03B2205/00; C03B2205/04; C03B2205/40; C03B2205/60; C03B2205/62; C03B2205/67; C03B2205/72
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
103 words
A METHOD FOR DRAWING A GLASS FIBER FROM A PREFORM COMPRISING THE STEPS OF: FORMING A HOT ZONE, EXPOSING AT LEAST A PORTION OF THE PREFORM TO THE HOT ZONE TO RAISE ITS TEMPERATURE TO AT LEAST THE SOFTENING POINT, DRAWING A GLASS FIBER FROM THE SOFTENED PORTION OF THE PREFORM, THE METHOD CHARACTERIZED IN THAT HOT ZONE IS PRODUCED BY MEANS OF A LASER BEAM AND THE LASER BEAM IS INTRODUCED INTO THE REGION OF THE HOT ZONE WITH AN APPROXIMATELY ANNULAR CROSS SECTION AND IN A DIRECTION THAT IS APPROXIMATELY COLINEAR WITH THE DIRECTION ALONG WHICH THE FIBER IS BEING DRAWN.
Claim 2
Independent Claim
103 words
A METHOD FOR DRAWING A GLASS FIBER FROM A PREFORM COMPRISING THE STEPS OF: FORMING A HOT ZONE, EXPOSING AT LEAST A PORTION OF THE PREFORM TO THE HOT ZONE TO RAISE ITS TEMPERATURE TO AT LEAST THE SOFTENING POINT, DRAWING A GLASS FIBER FROM THE SOFTENED PORTION OF THE PREFORM, THE METHOD CHARACTERIZED IN THAT HOT ZONE IS PRODUCED BY MEANS OF A LASER BEAM AND THE LASER BEAM IS INTRODUCED INTO THE REGION OF THE HOT ZONE WITH AN APPROXIMATELY ANNULAR CROSS SECTION AND IN A DIRECTION THAT IS APPROXIMATELY COLINEAR WITH THE DIRECTION ALONG WHICH THE FIBER IS BEING DRAWN.
Claim 3
Dependent Claim
21 words
The method of claim 1 in which the annular laser beam is directed onto the preform by an approximately conical reflector.
Claim 4
Dependent Claim
16 words
The method of claim 1 in which the laser beam is generated by a CO2 laser.
Claim 5
Dependent Claim
14 words
The method of claim 1 in which the fiber is drawn in a vacuum.
Claim 6
Dependent Claim
15 words
The method of claim 1 in which the fiber is drawn in an inert atmosphere.
Claim 7
Dependent Claim
44 words
The method of claim 1 in which the fiber is drawn in a reactive atmosphere with respect to the heated charge in order to alter the composition of the charge along its surface, thereby altering the refractive index of the surface of the preform.
Claim 8
Dependent Claim
27 words
The method of claim 1 in which the glass fiber consists essentially of an inorganic oxide and in which the fiber is drawn in an oxygen-containing atmosphere.
Claim 9
Dependent Claim
19 words
The method of claim 1 in which the preform includes at least two concentric bodies of differing refractive index.
Claim 10
Dependent Claim
20 words
The method of claim 8 in which the said at least two concentric bodies comprise a rod within a tube.
Claim 11
Dependent Claim
44 words
The method of claim 9 in which the bodies are non-contiguous and in which the atmosphere between the outer surface of the rod and the inner surface of the tube is evacuated, thereby reducing the possibility of gas bubble formation along the clad interface.
Claim 12
Dependent Claim
33 words
The method of claim 8 in which the said at least two concentric bodies both include silica and in which the outer body has a lower index of refraction than the inner body.
Claim 13
Dependent Claim
15 words
The method of claim 1 in which the preform consists essentially of a silica-base glass.
Claim 14
Dependent Claim
28 words
The method of claim 12 in which the preform consists essentially of material selected from the group consisting of pure silica, doped silica, borosilicate compositions, and soda-lime-silica compositions.
References Cited (Backward Citations)
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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) | 1978-02-10 | 1978-08-12 | 1979-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-10 | 1982-08-12 | 1983-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-10 | 1986-08-12 | 1987-02-11 | $7700.00 | Window Closed / Lapsed |