Optical fiber thermometer based on multimode interference effects

Abstract

An optical fiber thermometer based on multimode interference (MMI) effects is experimentally reported. At the proposed configuration, a multimode fiber (MMF) without cladding is gradually covered by a liquid column as the temperature rises which produces a displacement of the reflected spectrum as the liquid becomes the cladding of the MMF. A linear relationship between the peak wavelength shift and the applied temperature is obtained with a sensitivity as high as 0.4421 nm/°C.