Patent US4627867A successfully refreshed from Google Patents.
US4627867A
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Method for producing highly pure glass preform for optical fiber
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1985-03-04
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Granted: 1986-12-09
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Expires: 2005-03-04
Abstract
Abstract A method for producing a glass preform for an optical fiber by an outside vapor-phase deposition method, which comprises forming fine glass particles by jetting gaseous glass raw material and fuel gas from a first burner to deposit the particles on a seed rod to form a soot rod at such a temperature that a specific bulk density of the soot rod being formed is low and subsequently heating the soot rod by a second burner so as to increase the bulk density of the soot and then sintering the soot rod to obtain a transparent glass preform for an optical fiber, by which method, a highly pure glass preform is produced in a good deposition yield without cracking.
Inventors
- 👤 Gotaro Tanaka
- 👤 Hiroo Kanamori
- 👤 Futoshi Mizutani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:55
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/10; C03B37/12; C03B37/01; C03B37/012; C03B37/014; C03B37/01413; C03B37/0142; C03B37/01446; C03B2207/00; C03B2207/04; C03B2207/06; C03B2207/20; C03B2207/22; C03B2207/50; C03B2207/52; C03B2207/54; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
150 words
A method for producing a glass preform for an optical fiber by an outside vapor-phase deposition method, which comprises the steps of: forming glass soot particles by jetting and combusting gaseous glass-forming raw material and fuel gas from a first burner, in the presence of oxygen, depositing the particles on a seed rod with control being provided so as to form a soot rod at such a temperature that a specific bulk density ρ/ρ0, wherein ρ is a bulk density of the soot rod and ρ0 is a bulk density of perfectly sintered glass, of the soot rod being formed is from 0.02 to 0.1, subsequently heating the soot rod by a second burner with control being provided so as to increase the bulk density of the soot rod to from 0.15 to 0.5, and then sintering the soot rod to obtain a transparent glass preform for an optical fiber.
Claim 2
Independent Claim
150 words
A method for producing a glass preform for an optical fiber by an outside vapor-phase deposition method, which comprises the steps of: forming glass soot particles by jetting and combusting gaseous glass-forming raw material and fuel gas from a first burner, in the presence of oxygen, depositing the particles on a seed rod with control being provided so as to form a soot rod at such a temperature that a specific bulk density ρ/ρ0, wherein ρ is a bulk density of the soot rod and ρ0 is a bulk density of perfectly sintered glass, of the soot rod being formed is from 0.02 to 0.1, subsequently heating the soot rod by a second burner with control being provided so as to increase the bulk density of the soot rod to from 0.15 to 0.5, and then sintering the soot rod to obtain a transparent glass preform for an optical fiber.
References Cited (Backward Citations)
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US4310339A
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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) | 1989-12-08 | 1990-06-09 | 1990-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-08 | 1994-06-09 | 1994-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-08 | 1998-06-09 | 1998-12-09 | $7700.00 | Window Closed / Lapsed |