Abstract: The invention comes within the domain of synthetic images on a cathode scn and concerns a digital memory whose contents are cyclically read to constitute an image on the screen. The memory is divided into blocks each of which contains the data of a part of the image and which are cyclically controlled in such a way that within a line of the image, the blocks are read successively, whereas at the end of a line, a block is skipped. Thus, possible blanks in the image due to the breakdown of one of the blocks are distributed over the image and no longer erase a vertical column of the image.

Abstract: The invention relates to a device for designating an element of an image in a display assembly. The device comprises a system providing the coordinates of a marked element of the displayed image, comparator receiving the coordinates of the marked element and receiving from a vector generator the moving coordinates of successive elements of the image while refreshed, and a register controlled for load by simultaneous coincidence the two pairs of coordinates for receiving the address of the marked element from an address counter associated with a memory recording the data that define the image. The invention also relates to an assembly for displaying information from a data processor on a scanned display screen.