Separation of the Total Radiance Factor of Fluorescent Dyes

Ultraviolet and visible radiations are absorbed by fluorescent materials at short wavelengths and re-emitted at longer wavelengths. Spectral curve of fluorescent material consists of true and fluorescent reflection. The common Kubelka-Munk color model describes the reflectance of a translucent sample without considering fluorescence component; so, true spectral reflection of fluorescent materials should be separated from fluorescence emission. To this aim, there are some methods such as filter application to reduce fluorescence component, polychromatic and monochromatic spectrophotometers and computational methods to eliminate or decrease the fluorescence effect. At present study, to separate the true reflectance component from the fluorescence emission, the total spectral radiance factor of the fluorescent dyes was compared with the reflectance of the substrate through all visible wavelengths and exciting, crossover and emission region were determined. Accordingly, the total radiance factor curve can be separated into two parts of true and fluorescence reflection with considering of the Kubelka–Munk theory for the true reflectance part, simply and without any especial equipment.