US4009014A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical fiber manufacture
Assignee: International Standard Electric Corp
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Filing: 1975-09-03
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Granted: 1977-02-22
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Expires: 1995-09-03
Abstract
Abstract A fiber optic preform is provided by depositing phosphorus pentoxide as a dopant on the bore of a silica tube to form a high refractive index layer and collapsing the tube to form a core of high index phosphorus pentoxide doped silica.
Inventors
- 👤 Philip William Black
- 👤 John Irven
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:44
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/025; C03B37/029; C03B37/012; C03B37/014; C03B37/018; C03B37/01807; C03B37/01815; C03B37/01853; C03B37/01861; C03B37/01869; C03C; C03C21/00; C03B2201/00; C03B2201/02; C03B2201/06; C03B2201/08; C03B2201/10; C03B2201/20; C03B2201/28; C03B2201/30; C03B2201/31; C03B2201/32; C03B2201/40; C03B2201/42; C03B2203/00; C03B2203/10; C03B2203/22; C03B2203/28; C03B2203/36; C03B2205/00; C03B2205/12; C03B2205/16; C03B2207/00; C03B2207/80; C03B2207/85; C03B2207/87
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
85 words
A method for forming an optical fiber preform for producing low mode dispersion optical fibers comprising the steps of: depositing phosphorus pentoxide on the inner surface of a silica tube to provide a region of high index of refraction on said inner surface; heating the phosphorus pentoxide coated tube up to a first temperature of 1400° C to diffuse the phosphorus pentoxide into the silica; and subsequently heating the tube to a second temperature of 1700° C to collapse the tube and form the preform.
Claim 2
Independent Claim
85 words
A method for forming an optical fiber preform for producing low mode dispersion optical fibers comprising the steps of: depositing phosphorus pentoxide on the inner surface of a silica tube to provide a region of high index of refraction on said inner surface; heating the phosphorus pentoxide coated tube up to a first temperature of 1400° C to diffuse the phosphorus pentoxide into the silica; and subsequently heating the tube to a second temperature of 1700° C to collapse the tube and form the preform.
Claim 3
Independent Claim
98 words
A method for forming an optical fiber preform for producing a low dispersion multimode optical fiber comprising the steps of: heating a silica tube having a first index of refraction to a first temperature of 1400° C; depositing phosphorus pentoxide upon the inner surface of the tube while maintaining the tube at said first temperature to diffuse the phosphorus pentoxide into the silica during deposition for increasing the index of refraction of the inner surface of the tube; and heating the silica tube to a second temperature of 1700° C to collapse the tube and form the preform.
Claim 4
Independent Claim
98 words
A method for forming an optical fiber preform for producing a low dispersion multimode optical fiber comprising the steps of: heating a silica tube having a first index of refraction to a first temperature of 1400° C; depositing phosphorus pentoxide upon the inner surface of the tube while maintaining the tube at said first temperature to diffuse the phosphorus pentoxide into the silica during deposition for increasing the index of refraction of the inner surface of the tube; and heating the silica tube to a second temperature of 1700° C to collapse the tube and form the preform.
Claim 5
Dependent Claim
28 words
The method of claim 1 wherein the tube is heated to the first temperature for a period of time ranging from a few seconds to a few minutes.
References Cited (Backward Citations)
US3659915A
Cited
US3737293A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-22 | 1980-08-23 | 1981-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-22 | 1984-08-23 | 1985-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-22 | 1988-08-23 | 1989-02-22 | $7700.00 | Window Closed / Lapsed |