Characterization of encapsulating materials for fiber bragg grating-based temperature sensors

Abstract

An experimental study has been carried out for the characterization of encapsulating materials for fiber Bragg grating-based temperature sensors to prevent the formation of micro-cracks and devitrification on the fiber surface at elevated temperatures by making use of a rigid probe. The developed sensor probe was configured by encapsulating a type 1 fiber Bragg grating with an aluminum nitride tube and is used to measure temperatures from 20ıC to 500ıC. The adapted encapsulation technique validated the sensor to achieve linearity of 99.979%, sensitivity of 14.03 ˙ 0.02 pm/ıC, and good repeatability; its practical use in harsh environments is predicted.