Fibre optic sensor method and apparatus
US7564540B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 24, 2005 |
| Grant date | Jul 21, 2009 |
| Priority date | — |
| Expiry date | Jul 28, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/186
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This invention uses an interferometric fiber optic sensor, particularly a Sagnac or Michelson interferometer, in a first fiber to monitor a sensing length of the first fiber and to detect disturbances. Signals indicating disturbances are classified as being of interest or not of interest, depending on predetermined criteria. Disturbances of interest can be, for example, the breaking of reinforcement wires in concrete pipe, the breaking of wires in suspension cables, a fire, a pipeline leak, or an intrusion. A location sensor system is used to determine the location of disturbances of interest, and to confirm the interferometer signal to reduce noise. The location sensor system is a fiber optic sensor, such as a phase OTDR sensor or a Brillouin effect sensor, which can detect the location of events it senses. It is present either in the first fiber or in a separate fiber laid adjacent the first fiber along its sensing length, as for example in the same optical cable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.