Fiber Mach-Zehnder interferometer based on Multi-mode Fiber and Up-taper for Curvature Sensing applications

A novel curvature sensor comprize a section of multi-mode fiber and a up-taper is proposed and demonstrated experimentally. The whole fabrication process is quite simple and the sensor head is cost effective. Measurement results show that it has a maximum curvature sensitivity of -61.877nm/m(-1) at 1.1718m(-1) and -9.2115nm/m(-1) from 1.1718m-1 to 1.6583m(-1). Temperature sensitivity of 89.01 pm/degrees C within the range of 20 similar to 80 degrees C has also been achieved, which implies the possibility for measurement of temperature. High sensitivity and low-cost make it a preferable candidate for curvature sensing in practical applications.