US5157747A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photorefractive optical fiber
Assignee: Furukawa Electric North America Inc
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Filing: 1991-01-18
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Granted: 1992-10-20
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Expires: 2011-01-18
Abstract
Abstract Germanosilicate optical fiber having substantially higher GeO/GeO 2 ratio than conventional comparison-fiber is disclosed. The fiber has a loss at wavelength of 330 nm of at least 30 db/m.mole % GeO 2 . Such fiber can be advantageously used for making in line photorefractive Bragg gratings and other photorefractive fiber components. Fiber according to the invention can be produced by an inside deposition process (e.g., MCVD, PCVD), by an outside deposition process (e.g., VAD, OVD), or even a sol/gel process, and embodiments of the general method of making fiber according to the invention are disclosed.
Inventors
- 👤 Robert M. Aktins
- 👤 Katherine T. Nelson
- 👤 Kenneth L. Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:53
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/016; C03B37/01446; C03B37/018; C03B37/01853; C03B37/01861; C03B37/01869; G; G02; G02B; G02B6/00; G02B6/02; G02B6/02057; G02B6/02076; G02B6/02114; C03B2201/00; C03B2201/06; C03B2201/30; C03B2201/31; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
144 words
Apparatus comprising a silica-based optical fiber comprising a core and a cladding region surrounding the core, the core comprising silica and germanium oxide, associated with the fiber is a loss above background for conducted actinic radiation of wavelength 330 nm and an effective core refractive index, the apparatus being adapted for operation at an operating wavelength λ op ; CHARACTERIZED IN THAT at least a portion of the fiber has a loss above background for conducted actinic radiation of wavelength 330 nm that is at least 30 db/m.mole % GeO 2 , where mole % GeO 2 refers to the concentration of GeO 2 in the core that is associated with the effective core refractive index at λ op and said loss above background is a function of a substantial Ge +2 concentration per unit concentration of germanium in the core of the fiber.
Claim 2
Dependent Claim
144 words
Apparatus comprising a silica-based optical fiber comprising a core and a cladding region surrounding the core, the core comprising silica and germanium oxide, associated with the fiber is a loss above background for conducted actinic radiation of wavelength 330 nm and an effective core refractive index, the apparatus being adapted for operation at an operating wavelength λ op ; CHARACTERIZED IN THAT at least a portion of the fiber has a loss above background for conducted actinic radiation of wavelength 330 nm that is at least 30 db/m.mole % GeO 2 , where mole % GeO 2 refers to the concentration of GeO 2 in the core that is associated with the effective core refractive index at λ op and said loss above background is a function of a substantial Ge +2 concentration per unit concentration of germanium in the core of the fiber.
Claim 3
Dependent Claim
65 words
Apparatus of claim 1, wherein in said at least a portion of the fiber the core effective refractive index varies, as a function of distance along the fiber, repeatedly between about n max and n o , where n max and n o are, respectively, the maximum and minimum effective core refractive index, said at least portion of the fiber to be termed the grating.
Claim 4
Dependent Claim
73 words
Apparatus of claim 2, wherein the apparatus is a communication system comprising an optical fiber signal transmission path that comprises optical amplifier means and at least one grating, said amplifier means comprising means for injecting pump radiation of wavelength λ p <λ op into said transmission path, the variation of the core refractive index as a function of distance along the grating being selected such that the grating substantially reflects the pump radiation.
Claim 5
Dependent Claim
14 words
Apparatus of claim 2, wherein (n max -n o )/n o >10 -4 .
References Cited (Backward Citations)
US3916182A
Cited
US3891302A
Cited
US4212660A
Cited
WO1989002334A1
Cited
US5022734A
Cited
GB2210470A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-10-20 | 1996-04-20 | 1996-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-10-20 | 2000-04-20 | 2000-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-10-20 | 2004-04-20 | 2004-10-20 | $7700.00 | Window Closed / Lapsed |