Highly Sensitive Curvature Sensor Using an In-Fiber Mach–Zehnder Interferometer

Abstract

A highly sensitive curvature sensor using an in-fiber Mach-Zehnder interferometer is proposed and experimentally demonstrated. The sensor has a simple configuration-a short section of single-mode fiber is sandwiched between two short sections of multimode fibers to achieve a compact in-fiber Mach-Zehnder interferometer. The wavelength shift of selected dip in the Mach-Zehnder interference spectrum responds linearly with curvature and shows a high sensitivity up to -14.40±0.02 * m.