Patent ID: 6188435
Filing Date: 2001-02-13
Classification: H04N

Abstract:
Circuit for controlling beam current in a color picture tube which is driven by R, G, B signals, comprising:an input connected to a source of R, G, B signals;an amplifier for amplifying each of the R, G, B signals individually;means for calculating a separate current picture for each of the R, G, B beam currents by weighting each of the amplified R, G, B signals by means of gamma correction;a control circuit coupled to the calculating means for monitoring each of the R, G, B, current pictures and regulating picture sharpness in response to the current pictures;summing means for generating a weighted sum in response to the calculated current pictures;comparator/integrator for comparing the weighted sum of the current pictures with a beam current information itemand controlling gain of the amplifier in response to the comparison.