Sensing system using optical fiber suited to high temperatures
US7865044B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 2006 |
| Grant date | Jan 4, 2011 |
| Priority date | — |
| Expiry date | Dec 6, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/4402
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Remote sensing in an environment having temperatures greater than 300° C., using an optical fiber having a core (10), a cladding (20), and a metallic protective coating (30) on the cladding to protect a surface of the cladding, the cladding having a diameter greater than 150 μm, and a thickness of at least 50 μm. The larger diameter cladding means stress from the metallic protective layer can be reduced, giving lower optical loss and better hydrogen protection. A metal conduit (330) encapsulates the sensing fiber, and a pump evacuates the conduit to reduce hydrogen seepage. Ceramic splice protectors are used. OTDR is used to determine differential loss at different locations along the fiber. A reflective element at the far-end of the fiber eases calibration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.