Fiber-Optic Relative Humidity Sensors Based on Sol-Gel-Derived Claddings

• Main Author: 莊俊賢
• Other Authors: Lai-Kwan Chau
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/77196596482626841406

碩士 === 國立中正大學 === 化學研究所 === 89 === This research attempted to fabricate a relative humidity sensor by using sol-gel-derived materials to clad optical fibers. The sensor works according to refractive index change. When water condenses in the pores of the sol-gel matrix, the refractive index of the matrix will change. This change will cause the intensity of the light propagated through the optical fiber to be reduced. Such a change in intensity was used to determine the relative humidity of the environment. To improve the stability of the sensor, incorporation of various metal ions into the sol-gel matrices have been attempted. Based on UV-Vis spectroscopy and measurement of sensor signal, an improved stability of the sensor has been demonstrated. In addition, to improve the performance of the sensor, various factors such as sol-gel process parameters and optical design have been optimized. The linear dynamic range of the sensor for relative humidity was 10%~40% and the detection resolution of the sensor was 8.82%(Confidence Limits=95%).