US4149772A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical fibre having low mode dispersion
Assignee: Corning Inc
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Filing: 1977-11-28
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Granted: 1979-04-17
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Expires: 1997-11-28
Abstract
Abstract An optical fibre has a core and a plurality of rings surrounding the core. In one arrangement the core and subsequent alternate rings are light transmitting, while the intermediate rings are of cladding material. In an alternative arrangement the core and alternate rings are of cladding material and intermediate rings are light transmitting. The light transmitting rings can be of varying refractive index or of constant refractive index.
Inventors
- 👤 Rama Iyengar
- 👤 Felix P. Kapron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:33
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/02; G02B6/036; G02B6/03616; G02B6/03688; G02B6/02042; G02B6/028; G02B6/0288; G02B6/02295; G02B6/023; G02B6/10; G02B6/14
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
111 words
An optical fibre having a plurality of concentric, spaced, light transmission paths, each path for transmission of the same single optical mode, comprising a core and at least three rings surrounding the core, said rings and core of alternate high refractive index light transmitting material and low refractive index cladding material, relative to one another, to provide at least two concentric light transmitting paths separated by cladding material, the cross-sectional area of each light transmitting path defined by: V≈2(π/λ)√b.sup.2 -a.sup.2 ·NA where NA=numerical aperture; a is the inner radius and b is the outer radius of the light transmitting path, λ is the wavelength and V is less than about 2.4.
Claim 2
Dependent Claim
111 words
An optical fibre having a plurality of concentric, spaced, light transmission paths, each path for transmission of the same single optical mode, comprising a core and at least three rings surrounding the core, said rings and core of alternate high refractive index light transmitting material and low refractive index cladding material, relative to one another, to provide at least two concentric light transmitting paths separated by cladding material, the cross-sectional area of each light transmitting path defined by: V≈2(π/λ)√b.sup.2 -a.sup.2 ·NA where NA=numerical aperture; a is the inner radius and b is the outer radius of the light transmitting path, λ is the wavelength and V is less than about 2.4.
Claim 3
Dependent Claim
35 words
An optical fibre as claimed in claim 1, said core and subsequent alternate rings being of cladding material and the intermediate rings of light transmission material to provide said at least two light transmitting paths.
Claim 4
Dependent Claim
32 words
A fibre as claimed in claim 1, the cross-sectional areas of the light transmitting paths equal and the difference in refractive index between each light path and the related cladding is constant.
Claim 5
Dependent Claim
24 words
A fibre as claimed in claim 3, the refractive index of each light path different and the cross-sectional area of the light paths different.
Claim 6
Dependent Claim
25 words
An optical fibre as claimed in claim 1, said core and subsequent alternate rings comprising said light transmission paths, the intermediate rings of cladding material.
Claim 7
Dependent Claim
28 words
An optical fibre as claimed in claim 5, the core and each light transmitting ring having a reducing radial thickness and a substantially constant relatively higher refractive index.
Claim 8
Dependent Claim
32 words
An optical fibre as claimed in claim 5, the core and each light transmitting ring of the same radial thickness, the refractive index of the core and light transmitting rings reducing stepwise.
References Cited (Backward Citations)
US3157726A
Cited
US4000416A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-16 | 1982-10-16 | 1983-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-16 | 1986-10-16 | 1987-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-16 | 1990-10-16 | 1991-04-17 | $7700.00 | Window Closed / Lapsed |