Edge triggered apparatus and method for measuring strain in bragg gratings
US6566648B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 24, 2000 |
| Grant date | May 20, 2003 |
| Priority date | — |
| Expiry date | Mar 24, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M11/088
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for measuring strain of gratings written into an optical fiber. Optical radiation is transmitted over one or more contiguous predetermined wavelength ranges into a reference optical fiber network and an optical fiber network under test to produce a plurality of reference interference fringes and measurement interference fringes, respectively. The reference and measurement fringes are detected, and the reference fringes trigger the sampling of the measurement fringes. This results in the measurement fringes being sampled at 2&pgr; increments of the reference fringes. Each sampled measurement fringe of each wavelength sweep is transformed into a spatial domain waveform. The spatial domain waveforms are summed to form a summation spatial domain waveform that is used to determine location of each grating with respect to a reference reflector. A portion of each spatial domain waveform that corresponds to a particular grating is determined and transformed into a corresponding frequency spectrum representation. The strain on the grating at each wavelength of optical radiation is determined by determining the difference between the current wavelength and an earlier,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.