Optical fiber sensors based on pressure-induced temporal periodic variations in refractive index
US7138621B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 8, 2003 |
| Grant date | Nov 21, 2006 |
| Priority date | — |
| Expiry date | Apr 6, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/02071
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A optical fiber sensor for measuring temperature and/or pressure employs temporally created long period gratings. The gratings may be produced by a periodic change in the refractive index of the fiber along the fiber longitudinal axis caused by periodically spaced compressive and/or expansive forces or by spaced-apart unbalanced forces that cause periodic fiber micro-bending. Pressure and temperature are determined by measuring changes in both the wavelength at which light is coupled from a mode guided by a core to a different mode and an amount of such coupling. The gratings are created intrinsically and extrinsically. Single and multiple core fibers are used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.