摘要
通过在对称平面玻璃光波导上下表面各制备一层纳米多孔TiO2薄膜,形成了一种简单新颖的光学湿度传感器。其原理为,导波光在平面对称光波导中的传播损失依赖于纳米多孔TiO2薄膜的平均折射率,后者依赖于薄膜内部的水分子吸附量,而薄膜的水分子吸附量随着周围相对湿度的变化而变化,通过实时测量导波光传播损失的变化就能够感知外围的相对湿度。测试结果表明,在650nm波长下,相对湿度从20.47%逐渐增大到84.16%,光波导输出信号从0dB非线性衰减到1.82dB;当相对湿度大于60%时,传感器灵敏度相对较高。本文还初步研究了多孔薄膜厚度对湿度灵敏度的影响及传感器的迟滞效应。
A novel simple humidity sensor is prepared by using a syrra^etric slab glass waveguide whose two surfaces are coated with nanoporous TiO2 thin films. The humidity-sensing principle of the device is that the propagation loss of light guided in the waveguide relies on the average refractive index of nanoprous TiO2 film,and the latter is a function of the amount of water adsorbed in the film. Owing to the strong dependence of the amount of adsorbed water on the ambient humidity, the relative humidity （RH） around the sensor can be detected by in situ monitoring the output light intensity of the sensor. The ex- perimental results indicate that at 650 nm wavelength a gradual increase of RH from 20.47% to 84. 16% makes the signal attenuatuation nonlinearly increase from 0 dB to 1.82 dB. The sensor sensitivity is larger at RH 〉60% than that at RH 〈60%. The influence of thickness of nanoporous film on the sensor sensitivity and the hysteresis effect of the sensor are preliminarily investigated.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2011年第10期1479-1482,共4页
Journal of Optoelectronics·Laser
基金
国家重点基础研究发展计划"973"资助项目(2009CB320300)
国家自然科学基金资助项目(60978042)
集成光电子学国家重点联合实验室开放课题资助项目(2010KFB003)
中国科学院"百人计划"择优支持资助项目
