US3932160A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming low loss optical waveguide fibers
Assignee: AT&T Inc
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Filing: 1974-08-09
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Granted: 1976-01-13
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Expires: 1994-08-09
Abstract
Abstract A method is disclosed for fabricating an optical fiber by drawing a preform whose manufacture involves the deposition of a borosilicate layer. The method calls for borosilicate deposition by high temperature pyrolysis of two gases, with processing parameters chosen so as to cause an acicular structure in the deposited layer, a structure which contributes to the uniformity of the drawn fiber.
Inventors
- 👤 Irfan Camlibel
- 👤 Franklin Winston Dabby
- 👤 Douglas Arthur Pinnow
- 👤 LeGrand Gerard Van Uitert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:47
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/018; C03B2201/00; C03B2201/06; C03B2201/08; C03B2201/10; C03B2203/00; C03B2203/10; C03B2203/22; C03B2203/26
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
172 words
A method for fabricating an optical fiber by means of drawing a preform whose manufacture comprises the deposition of borosilicate on a cylindrical member by means of a process of high temperature pyrolysis of a first reactant chosen from the group consisting of SiH 4 , SiCl 4 , and SiBr 4 and a second reactant chosen from the group consisting of B 2 H 6 , BCl 3 , and BBr 3 , heating said preform to the fusing temperature of said deposited borosilicate layer, further heating said preform to the drawing temperature, and drawing said preform into a fiber, characterized in that 1. said first and second reactants are used in a ratio within the range of from 2:1 to 30:1 by volume in case said second reactant is borane and from 4:1 to 60:1 otherwise, and 2. said high temperature pyrolysis is carried out at a temperature within the range of from 900°C to 1,200°C, whereby said layer of borosilicate is deposited in the form of radially oriented needles.
Claim 2
Independent Claim
172 words
A method for fabricating an optical fiber by means of drawing a preform whose manufacture comprises the deposition of borosilicate on a cylindrical member by means of a process of high temperature pyrolysis of a first reactant chosen from the group consisting of SiH 4 , SiCl 4 , and SiBr 4 and a second reactant chosen from the group consisting of B 2 H 6 , BCl 3 , and BBr 3 , heating said preform to the fusing temperature of said deposited borosilicate layer, further heating said preform to the drawing temperature, and drawing said preform into a fiber, characterized in that 1. said first and second reactants are used in a ratio within the range of from 2:1 to 30:1 by volume in case said second reactant is borane and from 4:1 to 60:1 otherwise, and 2. said high temperature pyrolysis is carried out at a temperature within the range of from 900°C to 1,200°C, whereby said layer of borosilicate is deposited in the form of radially oriented needles.
Claim 3
Dependent Claim
32 words
Method of claim 1 in which said ratio between reactants is in the range of from 2:1 to 4:1 in case said second reactant is borane and from 4:1 to 8:1 otherwise.
Claim 4
Dependent Claim
32 words
Method of claim 1 in which said ratio between reactants is varied over the range of 2:1 to 9:1 in case said second reactant is borane and from 4:1 to 18:1 otherwise.
Claim 5
Dependent Claim
18 words
Method of claim 1 in which said high temperature pyrolysis is carried out by means of flame pyrolysis.
Claim 6
Dependent Claim
18 words
Method of claim 1 in which said high temperature pyrolysis is carried out by means of infrared radiation.
Claim 7
Dependent Claim
17 words
Method of claim 1 in which said high temperature pyrolysis is carried out in a reaction furnace.
Claim 8
Dependent Claim
15 words
Method of claim 1 in which an inert carrier gas is used along with reactants.
Claim 9
Dependent Claim
21 words
Method of claim 7 in which said carrier gas is used in an amount relative to reactants of at least 10:1.
Claim 10
Dependent Claim
20 words
Method of claim 7 in which said carrier gas is selected from the group consisting of helium, nitrogen, and argon.
Claim 11
Dependent Claim
24 words
Method of claim 9 in which said carrier gas is helium constituting approximately 96 percent of the mixture of carrier gas and reactant gases.
Claim 12
Dependent Claim
22 words
Method of claim 1 in which said deposit is essentially three parts SiO 2 and one part B 2 O 3 .
Claim 13
Dependent Claim
26 words
Method of claim 1 in which said borosilicate is enriched in silica content prior to drawing by burning B 2 O 3 out of the surface.
Claim 14
Dependent Claim
20 words
Method of claim 1 in which a protective layer of silica-enriched borosilicate is deposited on said borosilicate prior to drawing.
Claim 15
Dependent Claim
21 words
Method of claim 1 in which a protective layer of essentially pure silica is deposited on said borosilicate prior to drawing.
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) | 1979-01-12 | 1979-07-14 | 1980-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-12 | 1983-07-14 | 1984-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-12 | 1987-07-14 | 1988-01-13 | $7700.00 | Window Closed / Lapsed |