[Fabrication of relative humidity optical fiber sensor based on nafion-crystal violet sensing film]

With two kinds of sensing methods for relative humidity based on fluorescence and visible absorption respectively, crystal violet was opted as the molecule probe for humidity. The optical chemical sensing film for humidity was prepared when crystal violet was embedded in the Nafion gel. The relative humidity sensor was fabricated after the sensing film had been coupled with other components, such as optical fiber and detector, which possessed short response time ( < 2 min), high sensitivity (< or = 5% RH), wide dynamic range (30%-100%) and good reversibility (RSD < or = 2.6%) for relative humidity at 640 nm wavelength.