Parameters optimization of π-phase-shifted long-period fiber grating for gas sensing  

作　　者：蒋秀丽 顾铮■ 

机构地区：[1]Laboratory of Photoelectric Functional Films,Shanghai University of Science and Technology [2]Department of Math and Physics,Shanghai Institute of Electric Power

出　　处：《Optoelectronics Letters》2011年第1期22-25,共4页光电子快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.60777035);the Scientific Research Key Project Fund of the Ministry of Education (No.208040);the Shanghai Leading Academic Discipline Project (No.T0501)

摘　　要：The gas-sensitive film coated π-phase-shifted long-period fiber grating(LPFG),consisting of two same long-period fiber gratings cascaded by a regular fiber with length of half of the grating period,is proposed for gas sensing.The sensitivity of the sensor is defined by the change rate of the transmission at specific wavelength with respect to the film refractive index.The qualitative and numerical analyses show that to get a high sensitivity,the optimal coupling strength of each long-period fiber grating is √2 π/4.With this coupling strength,the longer the grating is,the higher sensitivity the sensor has.By choosing appropriate grating period,a high sensitivity for the film with a certain refractive index and thickness can be attained.

关 键 词：Chemical detection Diffraction gratings Gas detectors Light refraction Numerical analysis Optimization Refractive index REFRACTOMETERS SENSORS 

分 类 号：TN253[电子电信—物理电子学]