White-light interferometric fiber-optic strain sensor from three-peak-wavelength broadband LED source

摘要

A white-light fiber-optic interferometer working in the spatial domain, using a special three-peak-wavelength LED as a light source and one of the two arms of thf Michelson interferometer as a strain sensor, is presented. Based on the Gaussian spectrum distribution function, a simple spectrum-decomposing method is used to describe the special three-peak-wavelength LED source, Experimental and theoretical analyses show that this special three-peak-wavelength LED source can be used in white-light: Interferometry to simplify he problem of central-fringe identification. A white-light Michelson fiber-optic strain-sensing system that uses a tapered cantilever beam is described. Experimental results show that the strain measured by the fiber-optic sensor is linear and always less than the surrounding matrix. (C) 1997 Optical Society of America.