GB1260535A - High-speed printer employing a gas discharge matrix - Google Patents

Abstract

1,260,535. Discharge apparatus. MASSACHUSETTS INSTITUTE OF TECHNOLOGY. 25 April, 1969 [26 April, 1968], No. 21137/69. Heading H1X. [Also in Division B6] A high-speed selective printer comprises an insulating medium 4 formed with an array of perforations 5, each perforation including a pair of electrodes A, B adapted to selectively ionize gas within the perforations, the ionized gas being used to mark a record medium. Further electrodes 2, 3 are provided to maintain gas in the selected perforations in an ionized state for sufficient time to effect the marking. The electrode 2 may be perforated at 2<SP>1</SP> so that ionized gas expands out of the perforations to impinge on a record medium placed above the electrode 2. Alternatively the record medium (7, Fig. 4, not shown) may be passed between the medium 4 and the electrode 2<SP>11</SP>. In further modifications the record medium may itself form one electrode, or may be in contact with the upper electrode, in each case the record medium being conducting. The record medium may be marked thermally, e.g. by the hot ionized gas striking a thin white wax coating on a dark surface such as dyed paper, or by development of electrostatic charges formed on the medium, or chemically, e.g. by employing paper coated with sodium or potassium ferrocyanide, and developing with a tannic acid mist. The material 4 may be glass or ceramic. The electrodes A, B may be printed circuitry or single wires. The gas to be ionized may be atmospheric air, or nitrogen, argon or carbon dioxide in a controlled atmosphere.