THE STUDY OF OPTIC FIBER SENSORS FOR HUMIDITY APPLICATIONS

• Main Authors: Hao-yu Huang, 黃浩瑜
• Other Authors: Woo-Hu Tsai
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/63350847320915327736

碩士 === 大同大學 === 光電工程研究所 === 93 === In this thesis, we use the side-polished fiber structure to be our mainly experimental structure. We use the side-polished holder developed by our laboratory to polish the fiber side surface near the core region. After that, we do the hydrophilic preparation and spread the hydrophilic material uniformly on the side-polished surface. Using this structure to be humidity sensor, we can get the optical power variation is 0.825dB from 40% to 70% relative humidity. In order to enhance the sensitivity, we use the photolithography and the ICP-RIE dry etching technique to produce the long period fiber grating structure on the side-polished surface. In the experiment, we find the side-polished surface is quite well on the hydrophile after the plasma treatment. It is helpful on the hydrophilic material uniformly spread. This structure is quite linear and sensitivity on the relative humidity measurement. We can get the variation of the optical power is 4.913dB from 40% to 70% relative humidity. The long period fiber grating humidity sensor obviously transcends other optical humidity in the literature. And we will discuss these structures in the thesis.