Fiber Humidity Sensor Using Fluorescent Dye-Doped Plastics

Abstract

The humidity-sensing optical fiber consists of a glass core and polymer clad doped with umbelliferon dye. Under UV light pumping. the blue fluorescence intensity from this fiber increases linearly with increasing relative humidity in the range of 20 to 80%RH. In addition. it has a fast response time and is not influenced by the presence of NH 3 gas or HCl gas.