Temperature and Strain Independent Modal Interferometric Torsion Sensor Using Photonic Crystal Fiber

An all-fiber modal interferometric torsion sensor based on simple splicing configuration is presented wherein a photonic crystal fiber is spliced in between multimode fiber and single mode fiber. Appreciable torsion sensitivity of similar to 79.83 pm/degrees is obtained in the long dynamic range of 180 degrees. It is also found that there is no effect of strain and temperature on torsion sensitivity in the range of 0-4500 mu epsilon and 30-200 degrees C, respectively, leading to zero cross-sensitivity of torsion with strain and temperature.