Apparatus and method to improve quality of moving image displayed on liquid crystal display device
View Patent ↗A liquid crystal display device comprises a panel having pixel electrodes arranged at intersections of a plurality of signal lines via switching elements for transmitting display data and a plurality of scanning lines for transmitting control signals, and a control circuit for controlling the panel. The liquid crystal panel is divided into first pixel regions and second pixel regions adjacent to the first pixel regions. The control circuit carries out impulse driving in which the control signals transmitted to each of the scanning lines are activated two times in one frame period for displaying an image. The control circuit writes the display data in either one of the pixel regions and writes reset data in the other pixel regions when the control signals are activated once of the two times. By writing the reset data in the pixel regions, the display data written in an immediately preceding frame are reset. In consecutive frames, the display data written in the pixel regions are always reset in one frame period. Therefore, blurring in a moving image can be alleviated. Since writing the display data and the reset data is carried out separately in the first pixel regions and in the second pixel regions, flicker is prevented from occurring in a display screen.
1. A liquid crystal display device, comprising:
a liquid crystal panel in which a plurality of signal lines for transmitting display pixel data and a plurality of scanning lines for transmitting control signals are laid out vertically and horizontally, and pixel electrodes are arranged at intersections of the signal lines and the scanning lines via switching elements,
wherein the device has a hold control function in which an image to be displayed is output in one entire frame period, and an impulse control function in which an image to be displayed is output in a predetermined period within the one frame period and is not output during a remaining period within the one frame period,
wherein said hold control is carried out when said display image is shown with all of the pixel electrodes and is a still image,
wherein said impulse control is carried out when said display image is shown with all of the pixel electrodes and is a moving image,
wherein motion compensation is carried out by using DCT (Discrete Cosine Transform), and
wherein said display image is judged to be said moving image and said hold control is switched to said impulse control when compressed image information includes vector information indicating image motion.