Wide-range fiber-optic strain sensor based on LP01 mode evanescence

The sensing mechanism of this all-fiber device is based on wavelength-dependent bend-induced attenuation in a single-mode optical fiber operating at a specific wavelength above cut off. The presentation involves sensor technology, sensor instrumentation, optical signal processing and measurand reconstruction algorithms applicable to this proposed novel measurement technique. Performance and metrological properties of the sensor are discussed in single-pass and in double-pass configurations, together with the specific advantages of each particular set-up. The sensor is simple and very cost-effective since all its components are standard and relatively basic devices used in fiber-optic communications, and allows strain measurement up to 20%