PLURAL BEAM ELECTRON BEAM SCANNER UTILIZING A MODULATION GRID

A plurality of flat coded dynode members are sandwiched between an electron emitting cathode in the form of a flat plate and a flat target plate. Each dynode member has a plurality of apertures formed therein which are aligned with corresponding apertures on all the other dynodes to form an electron beam channel. The dynodes further each have a pair of separate conductive portions thereon arranged in a predetermined finger pattern, the finest of such finger patterns defining an elemental scanning area of the target plate. Each of such basic resolution elements is formed by means of a channel for each of a plurality of scanning beams. A modulation grid having apertures therein corresponding to the apertures on the dynodes and aligned therewith is placed between the cathode and target and is used to control the energization of the beams. A dynode having one of the finest finger patterns thereon has such finger patterns arranged so that each basic scanning element has a single aperture for each of the separate scanning beams, thereby enabling simultaneous scanning over the entire target area for the separate beams.