Control device for unifying the brightness of a display screen and method thereof

摘要

A brightness adjustment device for a display device including a microprocessor for outputting a brightness control signal according to a synchronizing signal provided from a display signal source; a parabolic wave generator for generating a parabolic wave according to the brightness control signal supplied from said microprocessor; a video pre-amplifier for summing a video signal provided from the display signal source and the parabolic wave supplied from the parabolic generator and amplifying the summed signal; and a video main amplifier for amplifying the video signal supplied from the video pre-amplifier and outputting the amplified video signal to a cathode ray tube. A method of brightness adjustment for the display device using the brightness adjustment device includes the steps of: receiving a synchronizing signal from a display signal source at the microprocessor; receiving a video signal from the display signal source at the video pre-amplifier; recognizing a frequency of the received synchronizing signal; generating and outputting a brightness control signal according to the discriminated frequency; generating and outputting a parabolic wave according to the brightness control signal; summing the parabolic wave and the video signal; amplifying the summed signal; and outputting the amplified signal to the cathode ray tube.