Temperature sensor based on a pressure-induced birefringent single-mode fiber loop mirror

A fiber-optic temperature sensor based on a pressure-induced birefringent single-mode fiber (SMF) loop mirror is developed. The pressure-induced birefringent SMF is made by applying a force against a short section of length of a SMF. The length of the sensing element for the temperature sensing is about 50 mm. Wavelength spacing between the two adjacent interference minima of the loop mirror can be tuned by varying the applied pressure. The sensitivity of the temperature measurement of 0.65 nm °C−1 is achieved experimentally. The proposed sensor is more convenient and simpler than that of a polarization-maintaining photonic crystal fiber or standard polarization-maintaining fibers