Electronic system for reading symbols

Abstract From the Canadian patent

A set of photoelectric transducers optically scan-, ning a line transverse to the direction of movement of a character-bearing document to be electronically read is, periodically actuated to pick up light from a multiplicity of elemental areas of that document and to generate electrical analog voltages commensurate with the brightness of these area The analog voltages are serially read out from one or more shift registers as a pulse train or several parallel pulse trains each undergoing digitization and subsequent storage in respective cells of an associated memory. A group of these cells contain, at a given instant, digital codes representative of the relative brightness of respective …