Abstract
A simple and highly sensitive phase-demodulation technique is proposed, and its use for a fiber Bragg grating strain sensor is experimentally demonstrated. Sampling a phase-modulated Mach–Zehnder output with controlled time delay produced two quadrature data streams that have relative quadrature phase difference (90°). The Bragg wavelength-dependent phase information is extracted by application of digital arctangent function and phase unwrapping to the quadrature signals. By use of this technique with a reference grating, strain sensing at as much as a 30-kHz sampling rate was obtained with strain resolution of 3.5 microstrains and 6 nanostrains/Hz in quasi-static and dynamic strain measurements, respectively.
Original language | English (US) |
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Pages (from-to) | 1106-1111 |
Number of pages | 6 |
Journal | Applied optics |
Volume | 39 |
Issue number | 7 |
DOIs | |
State | Published - Mar 1 2000 |
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Engineering (miscellaneous)
- Electrical and Electronic Engineering