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.
© 1981 Optical Society of America
M. Gottlieb and G. B. Brandt, "Temperature sensing in optical fibers using cladding and jacket loss effects," Appl. Opt. 20, 3867-3873 (1981)