A curvature sensing setup based on an asymmetric concatenated tapered Mach-Zehnder interferometer

A curvature sensor using an erbium-doped fiber (EDF) based on an asymmetric concatenated tapered MachZehnder Interferometer (MZI) is proposed. For this experiment, the tapers were fabricated by using an arc electrical fusion splicer in manual mode. This sensor had a sensitivity of - - 15.15632 nm/m(-1) in a curvature - range from of C = 0 to 0.782 m(-1) and with R-2 of 0.99645. Moreover, the transmission spectrum transference - with loss less than 13 dB was obtained, when the sensor was fixed in the middle and on the surface of a thin flexible metallic plate. The higher sensitivity was measured at 36.38107 nm/m(-1) in the range of 0.2346-0.391 - and R-2 = 0.99546. The sensor has the advantage to be easily fabricated and is capable to measure curvature in different ranges (with different sensitivities). The concatenated MZI sensor based on EDF has good transmission, due to the light coupled into the core and the strong cladding modes.