基于迈克尔逊干涉的光纤弯曲传感器

设计并研制了一种新型的基于迈克尔逊干涉的光纤弯曲传感器.该光纤弯曲传感器由两根光纤组成的光纤带固定于弹性弯曲结构上来产生迈克尔逊干涉信号,用光纤折射率匹配液填充微型腔,并施加音频振荡信号对相位干涉信号实现低频调制.采用相位生成载波技术对相位干涉信号进行调制和解调,实现了对曲率变化高精确度的检测.实验测试了该光纤弯曲传感器的相位干涉信号与光纤带弯曲曲率的关系,并与理论分析对比.结果表明该光纤弯曲传感器具有43.96 rad/m－1的灵敏度及0.004 m－1的高分辨率.

Optical Fiber Bending Sensor Based on Michelson Interferometer

A novel high sensitivity fiber optic bending sensor based on Michelson interferometry was developed.The sensing probe utilizes a fiber ribbon affixed onto an elastic structure to generate interference signals as a function of curvature.Further a micro-cavity filled with refractive index matching liquid was added to the optical path length and modulated in audio frequency to modify interference signal,which was demodulated using phase generated signal carrier technology to obtain a highly sensitive detection of curvature change.Experimental measurement of prototype shows that the fiber optic bending sensor can achieve a sensitivity of 43.96 rad/m－1 and a high resolution of 0.004 m－1.