光子晶体光纤温度压力传感器

An hybride optical fiber sensor is presented for the measurement of temperature and pressure in high temperature environment. The sensor is based on the configuration of an extrinsic Fabry-Perot interferometer(EFPI),which is formed by a Hollow Core Fiber(HCF) sandwiched between a section of Single Mode Fiber(SMF) and a section of of Photonic Crystal Fiber(PCF), and an intrinsic Fabry-Perot Interferometer(IFPI),which is formed by a section of PCF. Temperature measurement is achieved by thermal expansion effect and thermooptic effect, while pressure measurement is realized by the change of refractive index of gas. The demodulation of the sensor was realized by a self-made white light interferometry demodulator. In the environment of different temperature and pressure, the temperature and pressure optical fiber sensors whose cavity length is 306 μm and 1 535 μm were measured continuously. The experimental results show that the pressure sensitivity decreased with the increase of temperature. 1 460.5 nm/MPa is achieved at the temperature of 28℃ and the temperature response of the EFPI cavity is 17.4 nm/℃. The sensor is able to operate stably at temperature of 28~800℃ and pressure of 0~10 MPa.