US4204850A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carbon coating for a starting member used in producing optical waveguide
Assignee: Corning Glass Works
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Filing: 1977-08-26
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Granted: 1980-05-27
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Expires: 1997-08-26
Abstract
Abstract In making a preform for an optical waveguide, the bait rod is coated with carbon. After the preform is built up on the bait rod, it is easily removed. The carbon coating produces a smooth improved inner surface in the preform, thereby eliminating flaws which otherwise may be present when the preform is drawn into a waveguide.
Inventors
- 👤 Ellen K. Dominick
- 👤 George W. Scherer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:26
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/01466; C03B37/01473; C03B37/01486; C03B37/01493
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
110 words
The method of making a preform for an optical waveguide comprising: providing a substantially cylindrical starting member; applying a coating of substantially pure particulate carbon to the outside peripheral surface of said cylindrical starting member to form a carbon layer thereon; applying particulate material to the carbon layer on said starting member to form an adherent coating of glass; removing said starting member from said glass to cause separation between said carbon layer and the outside peripheral surface of said starting member or shearing within the carbon layer to produce a preform, and heating said preform to a temperature which disintegrates said carbon by oxidation and which consolidates said preform.
Claim 2
Independent Claim
110 words
The method of making a preform for an optical waveguide comprising: providing a substantially cylindrical starting member; applying a coating of substantially pure particulate carbon to the outside peripheral surface of said cylindrical starting member to form a carbon layer thereon; applying particulate material to the carbon layer on said starting member to form an adherent coating of glass; removing said starting member from said glass to cause separation between said carbon layer and the outside peripheral surface of said starting member or shearing within the carbon layer to produce a preform, and heating said preform to a temperature which disintegrates said carbon by oxidation and which consolidates said preform.
Claim 3
Dependent Claim
32 words
The method recited in claim 1 wherein the step of applying carbon includes rotating said starting member in an acetylene flame to deposit a coating of carbon soot on said starting member.
Claim 4
Dependent Claim
41 words
The method recited in claim 1 wherein the step of applying a carbon coating includes: dipping said starting member in a mixture of carbon dispersed in water; removing said starting member from said mixture; and drying the adherent layer of carbon.
Claim 5
Dependent Claim
17 words
The method recited in claim 1 wherein carbon is applied to an aluminum oxide mandrel starting member.
Claim 6
Dependent Claim
26 words
The method recited in claim 1 further comprising collapsing the center hole in said preform during consolidating and thereafter drawing said preform into an optical waveguide.
Claim 7
Dependent Claim
23 words
The method recited in claim 1 wherein the steps of heating and removing carbon are carried out in an atmosphere of oxidizing gas.
Claim 8
Dependent Claim
39 words
The method recited in claim 1 wherein the step of applying particulate material to said starting member includes depositing a coating of glass soot on the outside peripheral surface of said starting member by flame outside vapor phase oxidation.
Claim 9
Dependent Claim
53 words
The method recited in claim 7 further comprising: entraining in a gaseous material predetermined amounts of each of a plurality of constituents in vapor form; oxidizing said vapors in a flame to form a glass soot having a predetermined composition and applying said glass soot to the exterior peripheral surface of said member.
Claim 10
Dependent Claim
18 words
The method recited in claim 8 wherein said constituents include GeO 2 and B 2 O 3 .
Claim 11
Dependent Claim
32 words
The method recited in claim 7 further comprising radially varying the composition of the glass soot deposited on said starting member to produce a preform having a radially varying index of refraction.
Claim 12
Dependent Claim
42 words
The method recited in claim 1 further comprising: applying a coating of cladding glass having an index of refraction less than that of said first named coating, the composition of said cladding glass being compatible with that of said first named coating.
Claim 13
Dependent Claim
37 words
The method recited in claim 11 further comprising: heating the structure so formed to the drawing temperature of the materials thereof, and drawing the heated structure to reduce the cross-sectional area thereof to form an optical waveguide.
Claim 14
Dependent Claim
45 words
The method recited in claim 1 further comprising: heating said preform to consolidate said glass, to disintegrate the carbon coating on the hole from which said starting member was removed, and to collapse said hole; and thereafter drawing the coated preform into an optical waveguide.
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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) | 1983-05-27 | 1983-11-26 | 1984-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-27 | 1987-11-26 | 1988-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-27 | 1991-11-26 | 1992-05-27 | $7700.00 | Window Closed / Lapsed |