We report a novel demodulation scheme for the detection of small Bragg wavelength shifts in a fiber Bragg grating strain sensor by exploiting the optical feedback reflected from the grating structure back into a 1310 nm laser diode integrating a photodiode. The dynamic strain generated by a mechanical vibrator is applied transversely to the fiber Bragg grating and the desired longitudinal strain values inferred from the detected sawtooth-like optical feedback signals. Preliminary results demonstrate the feasibility of this demodulation technique for strain measurement which could be further extended to fiber Bragg grating-based sensors for the detection of different measurands in general.
Bibliographical noteInstrumentation and Measurement Technology Conference, 2006 (IMTC 2006), 24-27 April 2006, Sorrento (IT).
- Fiber Bragg grating sensor
- dynamic strain measurement
- optical feedback interferometry
Seat, H. C., Wang, Y., Hu, W., Bosch, T., Chen, X. F., & Zhang, L. (2006). Self-mixing-based demodulation technique for dynamic fiber Bragg grating strain sensors. In Proceedings of the IEEE : Instrumentation and Measurement Technology Conference, 2006. IMTC 2006 (pp. 2060-2065). IEEE. https://doi.org/10.1109/IMTC.2006.328456