Simultaneous measurement of curvature and temperature with fiber taper-based MZI containing fiber Bragg grating

A fiber sensor scheme for simultaneous measurement of curvature and temperature is presented. It comprises an optical fiber Mach–Zehnder interferometer (MZI) formed by cascading two waist-enlarged fiber tapers and a fiber Bragg grating (FBG) fabricated in between the two fiber tapers. Simultaneous measurement is realized based on the facts that the MZI is sensitive to both curvature and temperature, while the FBG is only sensitive to the later. Sensitivities of 6.73 nm/m−1 and 54.7 pm/°C are achieved experimentally for curvature and temperature measurements, respectively.