Mechanism measurement of micro-displacement based on a novel MZ interferometer

Measurement of micro-displacement sensor based on a novel MZ interferometer is proposed and experimentally demonstrated. It is formed by a spherical-shape structure incorporating a core-offset structure in single mode fibers(SMF). The core mode and cladding modes of SMF are utilized as optical arms of the in-line MZI. The incident light of the two arms can be coupled into the core mode, the resonant wavelength is sensitive to micro-displacement. Experimental results show that the sensor is capable of monitoring micro-displacement change from 0mm to 0.2mm with sensitivity of 183.68nm/mm with regular transmission spectrum and good mechanical strength. Other several physical parameters such pressure, load, vibration, strain can be translated to displacement changes, which make the proposed spherical-shape and core-offset to be used in various applications.