可同时测量温度和压力的高灵敏度光纤光栅传感器

报道一种新颖的基于单个光纤布拉格光栅的传感器。该传感器将光栅的一部分封装在周围填充聚合物的金属空腔里,另一部分固定在金属柱体内。由于固定的光栅部分不受应变的影响,而封装在聚合物的光栅同时受温度和应变的影响,因此该结构可实现温度和应变的分离传感。同时,这种聚合物封装的结构把施加在聚合物上的横向应力巧妙地转化为施加在光栅上的轴向应变,可大大提高其应变传感灵敏度。实验结果表明该传感器不但可以实现压力和温度的同时测量,而且其压力灵敏度系数可达9.65×10-3MPa-1,约为裸光栅的4770倍。

A novel high-sensitivity fiber grating sensor for simultaneous measurement of temperature and pressure

A novel sensor based on a single fiber Bragg grating is described.The sensor is configured by encapsulating half of a fiber Bragg grating in a polymer filled metal cylinder and fixing the other half to the metal cylinder.The fixed part of the fiber Bragg grating is immune to the strain while the other part is sensitive to both the strain and the temperature,therefore the novel structure can realize the separate sense of strain and temperature.Using a novel tactic to transfer the applied pressure to the axial extended-strain on the fiber Bragg grating,the pressure sensitivity can be greatly improved.The results show that this novel sensor can simultaneously measure pressure and temperature,meanwhile the pressure sensitivity reaches to 9.65×10-3MPa-1,which is about 4770 times larger than that of the bare fiber Bragg grating.