A new gas discharge tube for electrostatic printing

A new electrostatic printing gas discharge tube called "plasma printer" tube is presented, which is flat in shape, simple in structure and has inherent scanning capability. The gas-filled envelope of the tube contains several rectilinear anodes, rows of cathodes opposite to them, originally devised coupling electrodes placed side by side with the cathodes, and a row of recording stylus electrodes connected with the coupling electrodes. With the aid of ionization coupling, the glow discharge in the tube is transferred sequentially along the rows of the cathodes by three-phase pulse inputs, causing voltage pulses to be fed to the coupling electrodes. Together with video signal voltages, the voltage pulses fed to the recording styli produce latent electrostatic images of dot patterns on electrostatic recording paper. After developing and fixing the latent images by ordinary techniques, recorded copies are obtained. This principle of operation makes the device almost free from mechanical wear and enables it to operate at comparatively low voltages without complicated circuits and troublesome adjustments.