Elektrolumineszente Anzeigevorrichtung

A display device has an electroluminescent layer 14, Figs. 1, 3, contiguous with a photo-conductive layer 16, conductive strips 12 below the electroluminescent layer, conductive bus-bars 18 along sides of the photo-conductive layer 16 and means to illuminate a strip 22 of the layer 16 so as to activate the luminescent layer, e.g. at the junction of strips 22 and 121; in an alternative embodiment, Fig. 5, the electrode of the electroluminescent layer 34 is a plate 32 extending over the whole surface of layer 34 and at ground potential, and opposite pairs of bus-bars 38 contacting the photo-conductive layer 36 are connected to positive and negative potentials, such that luminescence only occurs at the intersection of light beams connecting both sets of bus-bars. Scanning may be by strip lights or by a rotating minor, and the devices may be spherical or cylindrical, or the scanning may be radial on a disc with circumferential electrodes. The electroluminescent material may be copper activated zinc sulphide or manganese activated zinc selenide, with cellulose, glass or polystyrene binder.