一种单模-多模-单模结构的干涉型光纤温度传感器

SMS光纤结构是一种近年来新兴的光纤器件,该结构光纤具有结构简单、易于实现、成本低廉、灵敏度高和无温度应力交叉敏感等特性.在光纤传感技术领域是一种继光纤光栅之后的具有广泛发展前景的光纤器件.从理论上分析了SMS结构和SMS级联结构的光纤传感原理,并从实验上研究了SMS结构和级联SMS结构的温度传感特性.实验表明:对于SMS结构光纤传感器,随着温度的增加,特征波长移动量逐渐增加,向长波方向漂移了4.05 nm,其传感器的温度灵敏度为15.76 pm/℃;对于级联SMS结构的光纤传感器,级联后不改变原来SMS结构的中心波长的位置,两个SMS结构仍然是独立的,不相互影响.所以说将两个SMS结构串联是可行的,可以用于温度和应力的同时测量,也可以用于分布式光纤传感器.

Inter ferometric Fiber Optic Temperature Sensor with Single mode Fiber-Multi mode Fiber-Single mode Fiber Structure

SMS fiber structure is a kind of optical fiber devices emerging in recent years, this optical fiber structure has the advantages of simple structure, easy to implement, low cost, high sensitivity and temperature stress of crosss ensitive features. In the field of optical fiber sensing technology, this structure has broad prospects for development following fiber grating. Theoretically, this paper analyzes the sensing principle of the SMS structure and the SMS cascade structure, and studies the corresponding structure of optical fiber, such as temperature characteristic. Through experiment, this paper studies the temperature sensing properties of the SMS structure and the SMS cascade structure. The experiment results show that with the increase of temperature, the characteristic wave length shift increases gradually and drifts in the direction of long wave 4.05 nm; Forfiber optic sensors with cascade SMS structure, the position of the central wave length of the original SMS structure is not changed after cascade, and the two SMS structures are still in depend entand do not affect each other. Soitis possible to connect two SMS structures in series for simultaneous temperature and stress measurements as well as for distributed fiber opticsensors.