EP0178806A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Variable coupler fibreoptic sensor
Assignee: Litton Marine Systems Inc
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Filing: 1985-09-20
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Granted: —
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Expires: 2005-09-20
Abstract
Abstract A variable coupler fibreoptic sensor in which a fused, tapered, biconical directional fibreoptic coupler (13) is encapsulated in a stress birefringent medium (15) the index of refraction of which changes with applied stress. The ratio of power in the output fibres (14) of the directional coupler varies with the change of index of refraction of the encapsulating medium as stress is applied to that medium.
Inventors
- 👤 Lawrence Henry Gilligan
- 👤 David William Gerdt
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 14:53
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: 9
Claim 1
Independent Claim
71 words
A fibreoptic sensor comprising fibreoptic coupler means (13) for dividing input light energy among a plurality of output fibres, characterised in that it further comprises a medium (15) for encapsulating the fibreoptic coupler means wherein the index of refraction of the medium is a function of stress applied to the medium, and detector means (17, 19) for providing an output signal representative of the ratio of energy in the output fibres.
Claim 2
Dependent Claim
71 words
A fibreoptic sensor comprising fibreoptic coupler means (13) for dividing input light energy among a plurality of output fibres, characterised in that it further comprises a medium (15) for encapsulating the fibreoptic coupler means wherein the index of refraction of the medium is a function of stress applied to the medium, and detector means (17, 19) for providing an output signal representative of the ratio of energy in the output fibres.
Claim 3
Dependent Claim
19 words
A fibreoptic sensor according to claim 1, characterised in that the medium (15) is a stress birefringent silicone elastomer.
Claim 4
Dependent Claim
21 words
A fibreoptic sensor according to claim 1 or 2, characterised in that an external stress is applied to the medium (15).
Claim 5
Dependent Claim
32 words
A fibreoptic sensor according to claim 1 or 2, characterised in that an internal stress is applied to the medium (15) by combining therein materials responsive to a parameter to be sensed.
Claim 6
Dependent Claim
25 words
A fibreoptic sensor according to any of the preceding claims, characterised in that the fibreoptic coupler (13) is a fused, tapered, biconical directional fibreoptic coupler.
Claim 7
Dependent Claim
20 words
A fibreoptic sensor according to any of the preceding claims, characterised in that the input light energy is infrared energy.
Claim 8
Dependent Claim
49 words
A fibreoptic sensor according to any of the preceding claims, characterised in that the detector means comprises a plurality of photodetector diodes (17) disposed to receive energy from the output fibres and a differential amplifier (19) to receive the outputs of the photodetector diodes and provide the output signal.
Claim 9
Dependent Claim
49 words
A fibreoptic sensor according to any of the preceding claims, characterised in that the sensor is configured as an accelerometer and the coupler (13) and the medium (15) are contained within a housing (22) with the input and output fibres (12, 14) extending through the wall of the housing.
References Cited (Backward Citations)
No citation records indexed.
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