in which pairs of sustain electrodes x and y are disposed in parallel as the first and second main electrodes and define cells as display elements at intersections with address electrodes a as the third electrodes the sustain electrodes x and y extend in the direction of rows i e in the horizontal direction on the screen the sustain electrodes y are used as scanning electrodes to select cells row by row in addressing the address electrodes a extend in the direction of columes i e in the vertical direction on the screen and are used as data electrodes to select cells column by column in the addressing an area where the sustain electrodes intersect the address electrodes is a display area that is a screen the drive unit 80 includes a controller 81 a frame memory 82 a data processing circuit 83 a sub frame memory 84 a power source circuit 85 an x driver 87 a y driver 88 and an address driver 89 frame data df are inputted to the drive unit 80 together with various synchronizing signals the frame date df are representative of luminance levels i e gradation levels for individual colors r g and b and determine the color of pixels the frame data df are stored in the frame memory 82 and then transferred to the data processing circuit 83 the.