EP0266974A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Sensor device
Assignee: Nortel Networks Ltd
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Filing: 1987-10-30
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Granted: —
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Expires: 2007-10-30
Abstract
Abstract A pressure sensor includes a resonator element (14) mounted on an optical fibre ferrule (11) whereby light signals for maintaining the resonator in a state of oscillation and for returning a modulated signal to a remite station are coupled to the resonator. The resonator is located in an evacuated cavity (16) and is mounted on a flexible diaphragm (13) whereby pressure changes may be detected as changes in the resonant frequency.
Inventors
- 👤 John Christopher Greenwood
- 👤 Peter William Graves
- 👤 Rosamund Carol Neat
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 20:58
CPC Classifications
G; G01; G01L; G01L1/00; G01L1/10; G01L1/103; G01D; G01D5/00; G01D5/26; G01D5/268; G01L1/18; G01L1/183; G01L1/186; G01L11/00; G01L11/02; G01L9/00; G01L9/0001; G01L9/0008; G01L9/0016; G01L9/0017; G01L9/0019; G01L9/002; G01L9/0041; G01L9/0076; G01L9/0077
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
97 words
A pressure sensor, including a flexible diaphragm on which a strain responsive resonator element is mounted, and an optical fibre disposed in register with the resonator element whereby, in use, that element is maintained in a state of resonance at a frequency corresponding to a strain applied to the diaphragm, characterized in that the fibre is supported in a ferrule on one end of which the diaphragm is mounted so as to define an air-tight cavity in which the resonator element is contained, and that said cavity is evacuated so as to define an absolute pressure reference.
Claim 2
Dependent Claim
97 words
A pressure sensor, including a flexible diaphragm on which a strain responsive resonator element is mounted, and an optical fibre disposed in register with the resonator element whereby, in use, that element is maintained in a state of resonance at a frequency corresponding to a strain applied to the diaphragm, characterized in that the fibre is supported in a ferrule on one end of which the diaphragm is mounted so as to define an air-tight cavity in which the resonator element is contained, and that said cavity is evacuated so as to define an absolute pressure reference.
Claim 3
Dependent Claim
25 words
A pressure sensor as claimed in claim 1 characterised in that the diaphragm and resonator are formed as a unitary body of single crystal silicon.
Claim 4
Dependent Claim
22 words
A pressure sensor as claimed in claim 1 or 2, characterised in that the diaphragm is bonded electrostatically to the ferrule end.
Claim 5
Dependent Claim
26 words
A pressure sensor as claimed in claim 1, 2 or 3, characterised in that a ball lens is provided between the optical fibre and the resonator.
Claim 6
Dependent Claim
17 words
A sensor system incorporating one or more sensors as claimed in any one of the proceding claims.
References Cited (Backward Citations)
No citation records indexed.
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