Display device configured to perform pseudo interlace scanning image display based on progressive image signal, driving method thereof, and display driving circuit

摘要

A display control circuit of a liquid crystal display device generates a double-speed progressive image signal by changing an input image signal based on interlaced scanning into a progressive scanning mode, and also by doubling the frame frequency. With the double-speed progressive image signal, a pixel value equivalent to an odd-numbered scanning line in an odd-numbered frame remains unchanged, a pixel value equivalent to an even-numbered scanning line is replaced with a black pixel value, a pixel value equivalent to an even-numbered scanning line in an even-numbered frame remains unchanged, and a pixel value equivalent to an odd-numbered scanning line is replaced with a black pixel value. An image that the double-speed interlace image signal represents is displayed on a liquid crystal panel.

主权项

1. A display device which is an active-matrix-type display device configured to display an image using a progressive image signal which is an image signal based on progressive scanning, comprising:
a display unit including a pixel array made up of a plurality of pixel formation units disposed in a matrix shape; and a display driving circuit including a first frame memory and a second frame memory, the display driving circuit configured to drive the display unit based on the progressive image signal by,
driving, during a frame period while image display is performed based on a first signal which is one frame signal of two adjacent frame signals included in the progressive image signal, the display unit so that images of odd-numbered scanning lines in an image that the first signal represents are formed of a pixel formation unit group in odd-numbered scanning lines in the pixel array, and also, a black display line is formed of a pixel formation unit group in even-numbered scanning lines in the pixel array,driving, during a frame period while image display is performed based on a second signal which is the other frame signal of the two adjacent frame signals, the display unit so that images of even-numbered scanning lines in an image that the second signal represents are formed of a pixel formation unit group in even-numbered scanning lines in the pixel array, and also, a black display line is formed of a pixel formation unit group in odd-numbered scanning lines in the pixel array,obtaining a signal value two frame ahead of the progressive image signal by sequentially writing to the first frame memory and reading from the first frame memory a signal value from which a signal value corresponding to a pixel which makes up the black display line from a signal value that the progressive image signal indicates has been excluded, and writing to the second frame memory and reading from the second frame memory the signal value readout from the first frame memory,obtaining an enhanced image signal in which temporal change in the progressive image signal is enhanced by comparing a signal value of the current frame in the progressive image signal with the signal value two frames ahead, anddriving the display unit based on the enhanced image signal.