Optical humidity-sensitive mechanism based on refractive index variation  

作　　者：王珍媛 顾铮■ 

机构地区：[1]College of Optoelectric and Electric Information Engineering,University of Shanghai for Science and Technology [2]Laboratory of Photo-Electric Functional Films,College of Science,University of Shanghai for Science and Technology

出　　处：《Chinese Optics Letters》2009年第9期756-759,共4页中国光学快报（英文版）

基　　金：This work was supported by the National Natural Science Foundation(No.60777035);the Scientific Research Key Project Fund of Ministry of Education(No.208040);the Research Project of Education Committee of Shanghai(No.07ZZ87);Shanghai Leading Academic Discipline Project(No.T0501).

摘　　要：A novel composite model is put forward for humidity-sensitive material based on Maxwell-Garnett and effective medium theory. The analytical expression of the relation between effective refractive index and relative humidity is shown with different absorption factors and porosities. The larger the absorption factor is, the higher the refractive index is. The refractive index of humidity-sensitive SiO2 film decreases with the increase of ceramic material porosity. The sensitivity of optical humidity sensor can reach the magnitude of 10-3. In comparison with the experimental humidity-sensing curve by the method of p-polarized reflectance and the analysis of mechanism, theoretical simulation is in agreement with experimental results. Therefore, this composite model is proved to be reasonable which lays new theoretical foundation in further research on optical humidity sensor.A novel composite model is put forward for humidity-sensitive material based on Maxwell-Garnett and effective medium theory. The analytical expression of the relation between effective refractive index and relative humidity is shown with different absorption factors and porosities. The larger the absorption factor is, the higher the refractive index is. The refractive index of humidity-sensitive SiO2 film decreases with the increase of ceramic material porosity. The sensitivity of optical humidity sensor can reach the magnitude of 10-3. In comparison with the experimental humidity-sensing curve by the method of p-polarized reflectance and the analysis of mechanism, theoretical simulation is in agreement with experimental results. Therefore, this composite model is proved to be reasonable which lays new theoretical foundation in further research on optical humidity sensor.

关 键 词：ABSORPTION Ceramic materials GARNETS Humidity sensors Light refraction MOISTURE Refractive index REFRACTOMETERS Silicon compounds 

分 类 号：O435.1[机械工程—光学工程]