单光纤光栅波谱展宽温度压力同时区分测量

Simultaneous Measurement of Temperature and Pressure using a Single Fiber Bragg Grating Based on Reflected Wave's Broadened Bandwidth

报道了利用单光纤布拉格光栅反射波带宽展宽技术实现温度与压力同时区分测量的新方案。通过聚合物材料将光栅粘接于双孔悬臂梁非均匀应变区 ,在压力作用下悬臂梁带动光栅发生非均匀应变 ,使布拉格反射波波长漂移的同时带宽展宽 ,而温度变化仅引起反射波波长漂移。在 2 0～ 10 0℃和 0～ 7.8N的温度和压力测量范围内 ,温度测量精度± 1.1℃ ,压力测量精度± 0 .18N ,布拉格反射波中心波长漂移量和带宽展宽量随温度和压力的变化呈良好的线性关系 ,线性度均高于 99.6 %。多次测量表明 ,此方案的展宽波形稳定 ,重复性好。

A novel approach for simultaneous measurement of temperature and pressure using a single fiber Bragg grating (FBG) based on reflected wave's broadened bandwidth is proposed and demonstrated. FBG is affixed on the non-uniformity strain area of double-hole cantilever beam by special polymer. Bragg reflected wavelength is shifted and reflected bandwidth is broadened by pressure change, while temperature change just leads to the shift of reflected wavelength. In the temperature range 20～100 ℃ and pressure range 0～7.8 N, the precisions of temperature measure and pressure measure are ±1.1 ℃ and ±0.18 N respectively. The response curves of FBG have good linearity which are higher than 99.6%. Reflection spectrum has a steady figure through repeated measurement.