Patent US4634858A successfully refreshed from Google Patents.
US4634858A
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Variable coupler fiberoptic sensor
Assignee: Litton Marine Systems Inc
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Filing: 1984-10-17
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Granted: 1987-01-06
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Expires: 2004-10-17
Abstract
Abstract A variable coupler fiberoptic sensor in which a fused, tapered, biconical directional fiberoptic coupler is encapsulated in a stress birefringent medium whose index of refraction changes with applied stress. The ratio of power in the output fibers of the directional coupler varies with the change of index of refraction of the encapsulating medium as stress is applied to the medium.
Inventors
- 👤 David W. Gerdt
- 👤 Lawrence H. Gilligan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:15
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/26; G02B6/28; G02B6/2804; G02B6/2821; G02B6/2835; G01; G01D; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01D5/353; G01D5/35338; G01D5/35341; G01D5/35345; G01D5/3537; G01D5/35377; G01L; G01L1/00; G01L1/24; G01L1/241; G01P; G01P15/00; G01P15/02; G01P15/08; G01P15/093; G02B6/2826; G02B6/283; G02F; G02F1/00; G02F1/01; G02F1/0128; G02F1/0131; G02F1/0134; G02F1/29; G02F1/31; G02F1/313; G02F1/3131
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
136 words
A fiberoptic sensor comprising: fiberoptic coupler means having a plurality of input optical fibers each having a core, said cores of said optical fibers merged and fused in a waist region to form a common optical core wherefrom a plurality of output optical fibers emerge, said fiberoptic coupler for distributing light energy incident to one of said input optical fibers between said plurality of output optical fibers, means having refractive index variable with stress applied thereto for encapulating said common optical core, such that said incident light energy is distributed between said plurality of output optical fibers as a function of stress applied to said refractive index means, and detector means coupled to said plurality of output optical fibers for providing output signals representative of said optical energy distribution in said plurality of output optical fibers.
Claim 2
Dependent Claim
136 words
A fiberoptic sensor comprising: fiberoptic coupler means having a plurality of input optical fibers each having a core, said cores of said optical fibers merged and fused in a waist region to form a common optical core wherefrom a plurality of output optical fibers emerge, said fiberoptic coupler for distributing light energy incident to one of said input optical fibers between said plurality of output optical fibers, means having refractive index variable with stress applied thereto for encapulating said common optical core, such that said incident light energy is distributed between said plurality of output optical fibers as a function of stress applied to said refractive index means, and detector means coupled to said plurality of output optical fibers for providing output signals representative of said optical energy distribution in said plurality of output optical fibers.
Claim 3
Dependent Claim
18 words
A fiberoptic sensor as recited in claim 1 wherein said encapsulating means is a stress birefringent silicone elastomer.
Claim 4
Dependent Claim
19 words
A fiberoptic sensor as recited in claim 1 further including means for applying external stress to said encapsulating means.
Claim 5
Dependent Claim
30 words
A fiberoptic sensor as recited in claim 1 further including means for applying internal stress to said encapsulating means by combining therein materials responsive to a parameter to be sensed.
Claim 6
Dependent Claim
56 words
A fiberoptic coupler according to claim 1 wherein said detector means comprises: a plurality of photodetector diodes disposed to receive optical energy from said outputfibers and provide electrical signals representative of received optical energy; at least one differential amplifier coupled to receive said electrical signals and provide said output signals representative of aid optical energy distribution.
Claim 7
Dependent Claim
53 words
A fiberoptic sensor as recited in claim 3 wherein said external stress means is a mass disposed on said refractive index means, thereby stressing said refractive index means in accordance with acceleration and causing a refractive index variation with a concomitant variation in optical energy distribution between said plurality of output optical fibers.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1990-01-05 | 1990-07-07 | 1991-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-05 | 1994-07-07 | 1995-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-05 | 1998-07-07 | 1999-01-06 | $7700.00 | Window Closed / Lapsed |