| 摘要 |
PROBLEM TO BE SOLVED: To provide a moire cancellation circuit that cancels moire caused in a color CRT display device displaying a video signal and can change a dot moire correction value with a small circuit scale at a low cost. SOLUTION: In order to horizontally vibrate a horizontal display position of a video image on a display screen, a vibration signal (MC) generated on the basis of an output from a horizontal frequency divider (1) and an output of a vertical frequency divider (2) takes a 1st state where the temporal mean value is a 1st value for each horizontal period (or its integer multiple) or a 2nd state where the temporal mean value is a 2nd value, the 1st state and the 2nd state are switched, a switching pattern between the 1st state and the 2nd state is inverted by each vertical period, and the vibration signal is pulse- width/modulated for a period shorter than the horizontal period at least in the 1st state. The vibration signal (MC) is integrated and the result is superimposed on an input voltage of a voltage controlled oscillator (6) configuring a horizontal synchronous control circuit of a display device.
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