Process and mfr. of polymer hollow objects

The image display system displays image data from an image memory on multiple image planes and vertical scrolling can be independently effected for each of the image planes displayed. Assuming that two image planes are displayed on upper and lower areas, display starting addresses lying in the vertical direction of the upper and lower image planes and stored in two registers are loaded into a counter via a switch in a display period of the upper and lower image planes to generate addresses in the vertical direction of the upper and lower image planes. The vertical scrolling operation only for one of the upper and lower image planes can be effected by sequentially updating the display starting addresses lying in the vertical direction of the upper and lower image planes and held in one of the registers. @(42pp Dwg.No.4/8)@