Simultaneous independent temperature and strainmeasurement usingin-fibre Bragg grating sensors

Abstract

A new technique for the simultaneous, independent measurement of temperature and strain using in-fibre Bragg grating sensors is proposed and demonstrated. Two Bragg gratings with closely spaced centre wavelengths are written either side of a splice between two fibres of different diameter. The gratings show similar temperature sensitivities but different strain responses to an applied stress. Maximum errors of ±17 µɛ and ±1° are reported over 2500 µɛ and 120°C measurement ranges.