A novel fiber Michelson interferometer based on cascaded twin core fiber and side-hole fiber

We present and demonstrate a novel fiber Michelson interferometer based on cascaded twin core fiber (TCF) and side-hole fiber (SHF) for curvature measurement. The interferometer is fabricated by fusing the TCF and SHF. The interferometer can measure curvature and temperature by monitoring the wavelength change of interferometer spectrum. The experiment investigated sensor's spectral responses to the curvature at different bending directions. Experimental results show that the bending sensitivities of the sensor are −6.968 nm/m−1 and 6.978 nm/m−1 at the bending direction of 0° and 180°, respectively. The temperature sensitivity of the interferometer is 10.37pm/°C.