US4286979A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of optical fibers using differential mode-group delay measurement
Assignee: AT&T Inc
•
Filing: 1980-06-23
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Granted: 1981-09-01
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Expires: 2000-06-23
Abstract
Abstract A method of forming optical fibers with improved mode dispersion characteristics is disclosed. The technique involves differential mode-group delay measurement to optimize dispersion by means of appropriate index of refraction configurations. The differential delay measurement technique involves selectively launching light into the multimode fiber using a single mode fiber which is spliced to the multimode fiber using an adjustable splice including an index matching fluid.
Inventors
- 👤 Michael J. Buckler
- 👤 Raymond B. Kummer
- 👤 Stephen C. Mettler
- 👤 Calvin M. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:26
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/025; C03B37/0253; G; G01; G01M; G01M11/00; G01M11/30; G01M11/33; G01M11/332; G01M11/338
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
111 words
In a method of forming a multimode optical fiber with improved mode dispersion characteristics comprising thermochemically reacting gaseous glass precursor reactants to form a multimode optical fiber; measuring the mode dispersion characteristics of the multimode fiber using a differential mode-group delay measurement technique; altering, in accordance with the results of the measurement, the thermochemical reaction of the gaseous glass precursor reactants to form a multimode optical fiber with optimized mode dispersion characteristics, the invention CHARACTERIZED IN THAT the differential mode-group delay measurement technique comprises launching light into the multimode fiber using a single mode fiber which is spliced to the multimode fiber using an adjustable splice comprising an index matching fluid.
Claim 2
Dependent Claim
111 words
In a method of forming a multimode optical fiber with improved mode dispersion characteristics comprising thermochemically reacting gaseous glass precursor reactants to form a multimode optical fiber; measuring the mode dispersion characteristics of the multimode fiber using a differential mode-group delay measurement technique; altering, in accordance with the results of the measurement, the thermochemical reaction of the gaseous glass precursor reactants to form a multimode optical fiber with optimized mode dispersion characteristics, the invention CHARACTERIZED IN THAT the differential mode-group delay measurement technique comprises launching light into the multimode fiber using a single mode fiber which is spliced to the multimode fiber using an adjustable splice comprising an index matching fluid.
Claim 3
Dependent Claim
29 words
The method of claim 1 wherein the index of refraction of the index matching fluid is within ten percent of the maximum index of refraction of the multimode fiber.
Claim 4
Dependent Claim
47 words
The method of claim 2 wherein the index of refraction of the index matching fluid has an index of refraction value between that of the maximum index of refraction value of the multimode fiber and the index of refraction value of the cladding of the multimode fiber.
Claim 5
Dependent Claim
29 words
The method of claim 2 wherein the beam diameter of the beam exiting the single mode fiber is less than twenty percent of the diameter of the multimode fiber.
Claim 6
Dependent Claim
30 words
The method of claim 4 wherein the beam diameter of the beam exiting the single mode fiber is less than ten percent of the diameter of the multimode fiber core.
Claim 7
Dependent Claim
23 words
The method of claim 4 wherein the axes of the single mode fiber and the multimode fiber are parallel to within one degree.
Claim 8
Dependent Claim
24 words
The method of claim 4 wherein the single mode fiber and the multimode fiber are separated by a distance of less than ten microns.
Claim 9
Dependent Claim
24 words
The method of claim 7 wherein the single mode fiber and the multimode fiber are separated by a distance of less than five microns.
Claim 10
Dependent Claim
27 words
The method of claim 7 wherein the multimode fiber is formed using the Modified Chemical Vapor Deposition process, the Vapor Axial Deposition process or the shoot process.
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) | 1984-08-31 | 1985-03-02 | 1985-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-31 | 1989-03-02 | 1989-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-31 | 1993-03-02 | 1993-09-01 | $7700.00 | Window Closed / Lapsed |