Method of displaying video images on a display device, e.g. a plasma display panel
View Patent ↗The present invention relates to a method of displaying video images on a display device and especially on a plasma display panel. The frame for displaying a video image is divided into two subframes, both comprising approximately the same number of subscans. The subscans of the first subframe are arranged in a first order in which their weights increase and those of the second subframe in the reverse order. The second subframe is consecutive to the first subframe. Each cell of the PDP changes state at most once during the first subframe. The same applies during the second subframe.
1. Method of displaying a video image on a display device, comprising a plurality of elementary cells, during a display frame, the display frame of a video image being composed of a plurality of periods called subscans during which each elementary cell is either in the on state or in the off state, each subscan having a weight proportional to its illumination period,
wherein each display frame is divided into first and second subframes during which each cell changes state at most once, in each subframe said first and second subframes comprising approximately the same number of subscans, the subscans of the first subframe being arranged in a decreasing order of their weight and the subscans of the second subframe being arranged in a increasing order of their weights,
and in that, for at least one transition from a lower grey level to the next upper grey level, a subscan which is in the on state for the lower grey level is in the off state for the next upper grey level.
2. Process according to claim 1 , wherein, for each cell, the said first and second subframes comprise approximately the same number of subscans during which the said cell is in the on state.
3. Process according to claim 2 , wherein the said first and second subframes comprise the same number of subscans.
4. Process according to claim 2 , wherein, if the first subframe comprises N subscans during which the cell is in the on state, the second subframe comprises N−1 or N subscans during which the cell is in the on state, N being a natural integer greater than or equal to 1.
5. Process according to claim 2 , wherein, if the first subframe comprises N subscans during which the cell is in the on state, the second subframe comprises N or N+1 subscans during which the cell is in the on state, N being a natural integer greater than or equal to zero.
6. Process according to claim 2 , wherein, if the first subframe comprises N subscans during which the cell is in the on state, the second subframe comprises N−1, N or N+1 subscans during which the cell is in the on state, N being a natural interger greater than or equal to 1.
7. Process according to claim 2 , wherein, if the first subframe comprises N subscans during which the cell is in the on state, the second subframe comprises N−2, N−1, N, N+1 or N+2 subscans during which the cell is in the on state, N being a natural integer greater than or equal to 2.
8. Method according to claim 1 , wherein the movement of the current video image with respect to the preceeding video image is estimated so as to generate a movement vector for each pixel of the video image and, for each pixel of the current video image, the subscans of the second subframe are displaced by an amount equal to half of the movement vector generated.
9. Plasma display panel, wherein it includes a device that implements the display method of claim 1 .