高灵敏度微腔型光纤应变温度传感器

High-sensitivity micro-cavity optical fiber strain and temperature sensor

提出了一种基于法布里-珀罗(F-P)微腔的新型、紧凑和鲁棒的光纤传感器,实现了对应变和温度的同时测量。该传感器的F-P微腔是通过用单模光纤(Single mode fiber,SMF)拼接一段确定长度的空芯光纤(Hollow core fiber,HCF),在HCF的尾部插入一段锥形SMF制备而成。其传感器机制是拉锥后的SMF在HCF内部移动,导致干涉F-P腔的长度发生变化,进而影响干涉光谱的变化。该结构设置初始腔长为80.4μm,应变波长灵敏度为Y=7.63×10^(-5)X+0.00669,拟合度为99.9%。在温度测试中,得到温度波长灵敏度为152 pm/℃,强度灵敏度为0.0294 dB/℃。通过双参数解调实现应变与温度同时测量。由于其具有成本低、线性度高、结构紧凑和灵敏度高特点,该传感器在应变与温度传感领域有一定的实用价值。

A new compact and robust optical fiber sensor based on Fabry-Perot(F-P)micro-cavity is proposed to realize simultaneous measurement of strain and temperature.The F-P micro-cavity of this sensor is produced by splicing Single mode fiber(SMF)with Hollow core fiber(HCF)with a certain length,and then inserting a section of tapered SMF into the end of HCF.The sensing mechanism is that the tapered SMF moves inside HCF,which causes the length of interference F-P cavity to change,and then affects the change of interference spectrum.The initial cavity length is 80.4μm,and the strain wavelength sensitivity is Y=7.63×10^(-5)X+0.00669,the corresponding fitted value is 99.9%.In the temperature test,the temperature wavelength sensitivity is 152 pm/℃,and the intensity sensitivity is 0.0294 dB/℃.The strain and temperature were measured simultaneously by two-parameter demodulation.Because of its low cost,high linearity,compact structure and high sensitivity,the sensor has certain practical value in the fields of strain and temperature sensing.