Simultaneous strain and temperature measurement using a no-core fiber-based modal interferometer with embedded fiber Bragg grating

摘要

A simple fiber-optic sensor based on a fiber Bragg grating (FBG) embedded in a fiber modal interferometer (MI) for simultaneous measurements of temperature and strain is proposed and experimentally demonstrated. The fiber MI is constructed by splicing two sections of the no-core fiber (NCF) between the single-mode fibers. Due to the different responses of the NCF-based MI and the FBG to the same temperature and strain, the discrimination between temperature and strain can be easily achieved. For a 0.01 -nm wavelength resolution, the resolution of the sensor is 0.216℃ and 6.75 με in temperature and strain, respectively.