SrTiO3:Pr,Al as an oxide compound phosphor shows potential application for a field emission display (FED). SrTiO3:Pr, Al phosphor was prepared directly by a continuous droplet to particle preparation using an ultrasonic spray pyrolysis. We have studied the processing mechanism of continuous droplet to particle. Powder surface and morphology were investigated as a function of reaction temperature and precursor solution. The powder surface was improved by adding H2O2 because of controlling the decomposition rate. After post-heat treatment for short residence time, the cathodoluminescent measurement was carried out (operational pressure 10(-6) Torr) using an electron beam excitation at 100 muA/cm(2) and the 800 voltage, and we obtained a sharp peak at 615 run, Our results obtained in this work suggest that SrTiO3:Pr,Al phosphors can be used as red phosphors in full-color FED. (C) 2002 Published by Elsevier Science Ltd and Techna S.r,l.