Compensating for changes in image characteristics in trichromatic picture tubes or cooperating monochromatic picture tubes, by controlling beam currents based on operating time of tube

摘要

The picture tubes emit visible light when electron beams hit phosphor material. The operating time of the picture tubes is detected, and the average beam currents are regulated by a control unit based on the operating time, so as to keep the set color balance constant over time. An independent claim is included for a television apparatus.