White uniformity measurements on color TV picture tubes

A minicomputer controlled scanning colorimeter has been developed, which automatically measures the distribution of chromaticity coordinates over the phosphor screen of a color picture tube. After measurement, the distribution of chromaticity difference vectors is displayed immediately on a CRT screen. Mean color difference is calculated for all points measured. This difference is highly correlated to visual evaluations by inspectors. These experiments indicate that white uniformity can be evaluated instrumentally.