Patent ID: 7045977

Claim:
A vertical/horizontal amplitude control device for controlling a vertical amplitude and a horizontal amplitude which change a vertical size and a horizontal size of an image display device for displaying a video signal, said vertical/horizontal amplitude control device comprising: a brightness level detector for detecting an average of a brightness level of said video signal and a peak of said brightness level in a vertical deflection period, and an average of a brightness level of said video signal and a peak of said brightness level in a horizontal deflection period; a vertical amplitude controller for controlling said vertical amplitude in order to change the vertical size of said image display device based on said average of said brightness level of said video signal and said peak of said brightness level in said vertical deflection period; and a horizontal amplitude controller for controlling said horizontal amplitude in order to change the horizontal size of said image display device based on said average of said brightness level of said video signal and said peak of said brightness level in said horizontal deflection period.