Polarimetric and Fiber Bragg Grating reflective hybrid sensor for simultaneous measurement of strain and temperature in composite material

摘要

In order to measure strain independently from temperature, hybrid solution based on a polarimetric and chirped Fiber Bragg Grating (FBG) sensors is proposed. The sensor is designed in a reflective configuration, where the chirped FBG is written on a highly birefringent (HB) fiber. The FBG act as a sensing element and also as a mirror for the polarimetric sensor. Information from both polarimetric and FBG part of the sensor can be determined independently from spectral analysis of the reflected light. Strain and temperature sensitivity of the proposed sensor solution is measured. Relation between both sensitivities are different for the FBG and the polarimetric sensor. Taking advantage of this, both temperature and strain can be determined by using only one sensing fiber.