Hybrid structured fiber-optic Fabry-Perot interferometer for simultaneous strain and temperature measurement base on phase demodulation

摘要

A novel dual-parameter sensor created by fusion splicing single mode fiber (SMF) and hollow core silica tube (HCST) isexperimentally demonstrated for simultaneous strain and temperature measurement based on hybrid structured fiberopticFabry-Perot interferometer (FPI) via phase demodulation. By the phase demodulation in the spatial frequencydomain, strain sensitivities of -0.002rad/με and 0.0006rad/με are respectively obtained for air-cavity and the silica-cavitywith the strain range from 0με to 1000με, and the temperature sensitivities of -0.0002rad/°C and -0.01rad/°C arerespectively for air-cavity and silica-cavity with the temperature range from 50°C to 450°C. Therefore, the differentsensing characteristics of silica-cavity and air-cavity to strain and temperature show that this structure can be furtherdeveloped to concurrently sense strain and temperature.