Temperature sensing in optical fibers using cladding and jacket loss effects

Abstract

A theoretical analysis is given of methods using transmission intensity effects in optical fibers as temperature sensors. The underlying mechanism involves temperature-dependent coupling of the evanescent field through a relatively thin cladding layer onto a lossy jacket. The temperature dependence comes about through the refractive indices of the core and cladding materials, which are chosen along with the fiber dimensions to give the desired response.