Intrinsic Fabry-Perot optical fiber sensors and their multiplexing
US7308162B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 8, 2003 |
| Grant date | Dec 11, 2007 |
| Priority date | — |
| Expiry date | Sep 8, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/02076
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An intrinsic Fabry-Perot optical sensor includes a thin film sandwiched between two fiber ends. When light is launched into the fiber, two reflections are generated at the two fiber/thin film interfaces due to a difference in refractive indices between the fibers and the film, giving rise to the sensor output. In another embodiment, a portion of the cladding of a fiber is removed, creating two parallel surfaces. Part of the evanescent fields of light propagating in the fiber is reflected at each of the surfaces, giving rise to the sensor output. In a third embodiment, the refractive index of a small portion of a fiber is changed through exposure to a laser beam or other radiation. Interference between reflections at the ends of the small portion give rise to the sensor output. Multiple sensors along a single fiber are multiplexed using an optical time domain reflectometry method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.