US Patent 7283179 Liquid crystal television apparatus

Disclosed herein is a video signal process circuit that includes a control circuit having a level detection circuit and a dynamic range switch circuit. In the control circuit and a microcomputer, an average luminance of an image displayed on a liquid crystal panel via a liquid crystal driver circuit is detected. When the average luminance is equal to or over a level YSmax, an upper limit of the dynamic range is expanded, so that a signal level of a composite video signal in which white blur can occur can be digitized to a digital signal without being limited by the upper limit gradation, reducing the white blur of the image to improve the quality of the image.