光纤光栅封装耦合对应变传感增敏的实验研究

Experimental study on strain sensing sensitivity enhancement resulting form coated coupling

目的 研究光纤Bragg光栅与基底材料封装耦合对应变传感的增敏问题。方法 选用弹性模量小、耐180℃度高温且对温度敏感极小的有机聚合物材料,对裸光纤光栅进行封装,封装中采用特殊的偶连工艺,实现了封装材料与光纤光栅的牢固耦合并对两种外型尺寸的封装进行了研究对比。结果 封装后的光纤光栅对应变传感有增敏作用,FS光纤光栅取得了较高的应力灵敏度,与裸光纤光栅报道值比较增敏1174倍。结论 封装后的光纤光栅应力响应曲线具有良好的线性。通过对封装结构及尺寸优化,可以实现量程与灵敏度的最优组合。

Aim A study on the problem of strain sensing sensitivity enhancement resulting from the coated coupling of fiber Bragg grating with substrate material is the purpose.Methods An organic poly-meric compound with small modulus of elastricity.High temperature 180℃ resistant property and min sensitivity to temperature has been selected for coating the bare fiber grating.A special coupling technology has been used in the coating process.Realizing firm coupling of the coating material with the fiber grating.Acomparison study on two coatings of different external dimensions has been carried out.Results The fiber grating after coating has sensitivity-enhancing effect for strain sensing. FS obtaining higher stress sensitivity for the coated fiber grating.Comparing with the reported value of bare fiber grating.A sensitivity enhancement of 1 174 times has been achieved for the coated fiber grating.Conclusion The stress response characteristic of the coated fiber grating has good linearity. Through optimization of the coating structure and dimensions, an optimal combination of the measuring range and the sensitivity can be realized.