Optical character recognition system including scanned diode matrix

Claim 1

An optical character recognition system comprising a photo head which includes a photodiode matrix defined by rows and columns of photodiodes adapted repeatedly to scan a character image to be recognized, a number of tapped delay lines to which information is transferred during the scan from the photohead, the length of said delay lines being such that information relating substantially to the whole of a character image can be stored therein, a detector arrangement capable of recognizing predetermined features of a plurality of different characters comprising a number of similar gating arrangements to each of which signals from selected taps on the delay lines are fed to provide output signals when the signals from the said taps are representative of a predetermined number of black and white points on the photodiode matrix indicative of a feature of the character scanned, a separate distinctive feature being detected by each gating arrangement, a multistage shift register into which output signals from said detectOr are fed and character detector means which provides a final output signal indicating that a particular character has been recognized when predetermined signal states obtain in selected stages of the said register.