光子晶体光纤温度压力传感器

提出了一种在高温环境下同时测量温度和气压的光子晶体光纤温度压力传感器.在普通单模光纤和光子晶体光纤之间熔接一段空心光纤构成干涉结构.空心光纤段构成非本征法布里-珀罗干涉仪,利用光子晶体光纤的微孔与外界相通,通过气体折射率变化来测量环境中的气压变化;光子晶体光纤段构成本征法布里-珀罗干涉仪,利用热膨胀效应和热光效应来测量环境中的温度.传感器的解调通过自制的白光干涉解调仪实现,实验通过测量腔长得到被测环境的温度和气压.在不同温度和气压环境下,对腔长分别为306μm和1535μm的温度压力光纤传感器进行连续测量.实验结果表明,传感器能够在28~800℃的温度下和0~10 MPa的气压下稳定工作,测量范围内温度灵敏度可达17.4 nm/℃,压力灵敏度随温度增加而降低,在28℃时可达1460.5 nm/MPa.

Photonic Crystal Fiber Temperature and Pressure Sensor

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 306μm and 1535μm were measured continuously.The experimental results show that the pressure sensitivity decreased with the increase of temperature.1460.5 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.