Abstract
A novel concept of optical-fiber humidity sensor using cellulose nanocrystals (CNC) composite fiber using electrospinning is presented. The humidity sensor measures relative humidity based on the effective refractive index change due to water vapor absorption. A simple evanescent detection scheme is set up for the fiber sensor where evanescent absorbance can be measured directly proportional to the vapor concentration and the effective fraction of the total guided power in the sensing region of the fiber. Due to cellulose's high affinity to water, the sensor should exhibit relatively high sensitivity compare to non-cellulose based sensor. In this report, both fabrication of the sensor and experiment will be presented.