Characterization of Phosphor Materials for Use In Plasma Display Panel by Time-Resolved Vacuum-Ultraviolet Laser Spectrometry

Phosphor materials that were manufactured for use in a plasma display panel (PDP) were investigated by employing a newly designed time-resolved vacuum-ultraviolet (VUV) spectrometer, which consists of a pulsed VUV laser and a fast photodetector. The VUV spectrometer was used to collect quantum efficiency data as well as the rise and decay times for the PDP phosphor luminescence. Both the rise and decay times increased with decreasing excitation wavelength in the VUV region. This result can be explained by a change in the mechanisms of photoexcitation and luminescence, that is, from charge-transfer excitation to host-lattice excitation below 200 nm. The present instrument was also used for an evaluation of the phosphor materials (Ba1-xMgAl10O17:Eu^2-x) by changing the Eu^2- concentration. The obtained data suggest that the impurities and defects are located inside the host crystal. Thus, the VUV spectrometer constructed in this study has considerable potential for use in investigating the nature of PDP phosphor materials.