Three samples, Tb~(3+)/PVA. Eu~(3+)/PVA and Tb~(3+),Eu~(3+)/PVA were prepared by slow evaporation method. The excitation and emission spectra of each sample were analyzed. Red, green and blue emissions from PVA film doped with both Tb~(3+) and Eu~(3+) were obtained for a single excitation at 380 nm. From the emission spectra the colour coordinates for each of the emission lines were calculated. The colour purity of each colour estimated from the fluorescence spectrum with the help of CIE 1931 XYZ colour space. The red emission from Eu~(3+) shows 100% purity whiles the green emission from Tb~(3+) shows 98.7% purity. Tb3+ ions also give blue emission with colour purity of 100%.
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