作　　者： ; ; ; ; ; ;

机构地区： 北京邮电大学电子工程学院光通信与光波技术教育部重点实验室

出　　处： 《光子学报》 2009年第4期775-779,共5页

摘　　要： 阐述了光纤Bragg光栅化学传感的基本原理,推导并利用数值计算得出了腐蚀掉包层后的光纤Bragg光栅的纤芯有效折射率随外界折射率变化的关系.分析了温度对这种传感器造成的误差.研究表明,温度会造成光纤光栅变化和改变溶液折射率的大小,从而对传感器的测量造成影响.设计了一种温度补偿方案.实验分别研究了低浓度溶液和高浓度溶液中传感头两段不同光栅区的Bragg波长随温度的变化.结果表明:在清水中,传感头两段光栅区Bragg波长受到温度变化的影响基本相同,通过测量波长的差值可消除温度的影响;高浓度溶液中,传感头受温度影响造成的总波长漂移量约为未被腐蚀光栅区的波长漂移量的0.6,与理论的结果基本一致.传感头受温度影响造成的总波长漂移量可由未被腐蚀光栅区波长漂移量的大小得出,进而可消除温度对溶液传感的影响. The chemical sensing principle based on Fiber Bragg Grating （FBG） was presented. The relation between effective core index and surrounding index of etched FBG was derived and obtained by numerical calculation. The error of sensing affected by temperature was discussed. The results show that the sensor sensitivity is affected by temperature through both the FBGs and the refractive index of chemical solutions change. A scheme of temperature-insensitive chemical sensor based on FBGs was designed. Wavelength shift of sensor versus temperature for two FBGs in low and high concentration of propylene glycol solution is experimentally investigated. The result indicates that, two wavelength shifts of the sensor in purified water exhibit almost the same thermal effects, so that the thermal effect can be eliminated by measuring the wavelength difference. The ratio between entire wavelength shift with thermal effect and wavelength shift of grating not etched is 0.6, which is basically the same as theoretical result. The entire wavelength shift with thermal effect can be educed by wavelength shift of grating not etched, eliminating the thermal effect in solution sensing.

关 键 词： 光纤布喇格光栅 化学传感器 折射率 温度补偿

领　　域： [自动化与计算机技术] [自动化与计算机技术] [电子电信]