Method of driving a flat type of cathode ray tube to provide uniformity of electron beam emission characteristics for a plurality of beam sources

摘要

A method of producing uniformity of emission a characteristics of a plurality of electron beam sources in a cathode ray tube, by deriving and storing data values for producing respective correction voltages to be applied to modify the emission characteristics. Each data value is obtained by sensing a current which flows through one of the control electrodes when a high voltage electrode is set to a relatively low potential, comparing this current with a reference value and storing the difference for use in subsequently producing a correction voltage. Data values are derived during successive time intervals, with corresponding correction voltages being successively applied to achieve feedback operation, for greater correction accuracy.