Temperature-insensitive curvature sensor based on anti-resonant reflection guidance and Mach-Zehnder interferometer hybrid mechanism

A temperature-insensitive optical fiber curvature sensor based on hollow-core fiber is proposed. The hybrid guidance mechanism is a combination of anti-resonant reflecting guidance and the Mach-Zehnder interferometer. The curvature can be detected through the wavelength interval between the two kinds of lossy dips resulting from the two above-mentioned guidance mechanisms. The curvature sensitivity is -0.54 nm/m(-1) and -2.02 nm/m(-1 )in the curvature range of [0 m(-1), 7.04 m(-1)] and [7.04 m(-1), 11.87 m(-1)], respectively. And the temperature cross-sensitivity of the sensor is only 5.54 pm degrees C-1, which makes the device attractive for potential applications in curvature measurements. (C) 2019 The Japan Society of Applied Physics