Patent ID: 6353435
Filing Date: 2002-03-05
Classification: G09G

Abstract:
A liquid crystal display control apparatus for generating intermediate gray-scale display data, comprising:a display on/off data generation circuit which generates plural display on/off data per pixel corresponding to M frame periods of a video output signal outputted from the liquid crystal display control apparatus to a liquid crystal display in N frame periods of a video input signal inputted to the liquid crystal display apparatus on a pixel unit basis in response to gray-scale data of pixel units included in the video input signal (M>N, M and N being integers), the M frame periods of the video output signal being defined by a frame period signal included in the video output signal, the N frame periods of the video input signal being defined by a vertical synchronous signal included in the video input signal, a frequency of the frame period signal being different from a frequency of the vertical synchronous signal; a write control circuit which writes the plural display on/off data per pixel corresponding to M frame periods of the video output signal generated by the on/off data generation circuit into a frame memory during N frame periods of the video input signal; and a read control circuit which sequentially reads out, from the frame memory, display on/off data corresponding to M frame periods of the video output signal written in the frame memory in synchronism with one display scan period of the video output signal; wherein the write control circuit and the read control circuit enable displaying the video output signal on the liquid crystal display at a frequency of 2.5 times a frequency of the video input signal.