镀膜长周期光纤光栅的折射率传感特性  

Refractive Index Sensing Characteristics of the Coated Long-Period Fiber Grating

作　　者：欧启标[1] 罗文志 咸锦照[3] 黄尚荣[1] 曾庆科[1] 秦子雄[3] 

机构地区：[1]广西师范大学电子工程学院,桂林541004 [2]上海豪仕杰喷码技术有限公司,奉贤区201404 [3]广西师范大学物理科学与技术学院,桂林541004

出　　处：《光散射学报》2011年第3期213-218,共6页The Journal of Light Scattering

基　　金：广西教育厅科研项目(桂教科研[2009]25号)

摘　　要：基于严格的光栅三包层模型及其色散方程,对镀膜长周期光纤光栅的折射率传感特性进行了详细的研究。研究发现,镀膜长周期光纤光栅的谐振波长随环境折射率的变化而变化,而且这种变化有一个跳跃,跳跃后的变化与跳跃前相同:如跳跃前向短波方向漂移,则跳跃后也向短波方向漂移。镀膜后,长周期光纤光栅的折射率探测范围得到拓宽,而且探测的灵敏度比没有镀膜时高一个数量级以上。薄膜厚度越接近最优厚度(OOT),镀膜长周期光纤光栅的灵敏度越高。Based on the model of triple-clad long-period fiber grating and characteristic equation,the refractive index sensing characteristics of the coated long-period fiber grating is studied in this paper.Conclusion is drawn that,the resonant wavelength of the coated long-period fiber grating varies with the changes of the environment refractive index,and in the variation there exists a leap.The resonant wavelength maintains the same before and after the leap： if it shifts towards the short-wave before the leap,then it will sustain in the same direction after the leap.After coated,the detected range of the LPFG refractive index would be widened,and the detecting sensibility of the coated LPFG would be at least an order of magnitude higher than it is without being coated.What’s more,the closer the overlay thickness approaches to OOT,the higher the sensibility of the coated LPFG will be.

关 键 词：长周期光纤光栅(LPFG) 环境折射率 谐振波长 灵敏度 

分 类 号：TN253[电子电信—物理电子学]