Hybrid all-fiber sensor for simultaneous strain and temperature measurements based on Mach-Zehnder interferometer

摘要

A hybrid all-fiber optic sensor for simultaneous detection of temperature and strain is proposed. The system comprises two different types of Mach-Zehnder interferometers (MZI) and sensing method is based on the joint evaluation of the strain (by a temperature-insensitive photonic crystal fiber (PCF) formed by a pair of long-period gratings (LPGs)) and of strain/temperature measurement (by a conventional single mode fiber (SMF) based MZI). It is shown that shorter wavelength for SMF-MZI and higher wavelength for PCF-MZI leads to larger phase shifts which improves the accuracy of measurements. (C) 2015 Elsevier GmbH. All rights reserved.