Dual fiber-optic Fabry-Perot interferometer strain sensor with low-cost light-emitting diode light source

Abstract

A prototype strain sensor based on a dual fiber-optic Fabry- Perot interferometer FFPI was successfully implemented experimen- tally. The light source was a low-cost communication light-emitting diode, replacing the expensive laser diode. No costly Faraday isolator was re- quired in this sensing system. The dynamic strain modulation in the sensing part of this setup was performed using a piezoelectric trans- ducer. The interesting dynamic strain signal could be extracted at the optical receiver by optical signal demodulation in the reference FFPI. The temperature variation of the sensing part was simultaneously de-