Patent ID: 6545718
Filing Date: 2003-04-08
Classification: G09G

Abstract:
A cathode ray tube for performing color image display by forming a single screen by joining a plurality of divided screens being formed by scanning of the plurality of electron beams by partially overlapping each other, comprising:a signal dividing means for dividing an inputted video signal into a video signal for the plurality of divided screens; a storage means for storing a plurality of correction coefficient for each color corresponding to a plurality of signal levels; a signal level detection means for detecting a signal level of an input video signal for each color; a calculating means for calculating an appropriate correction coefficient for each color to be used for modulation control of brightness among a plurality of correction coefficient stored in the storage means on the basis of the signal level detected by the signal level detection means; a brightness modulation means for performing control corresponding to a signal level on each of the plurality of video signals for a divided screen so that the sum total of brightness at the same pixel position in an overlapped region on the screen, scanned on the basis of the plurality of video signals for the divided screens, equals to brightness at the same pixel position on an original image by using a correction coefficient for each color calculated through the calculating means; and a plurality of electron guns for emitting a plurality of electron beams, which scans said plurality of divided screens based on a video signal where modulation control has been performed by said brightness modulation means.