| 摘要 |
A method of recognition of signs in which a scanning beam, passed circularly across the overall line width of a sign, is caused to follow up the contour of a sign and in which a signal sequence significant of the sign is derived from further circular scanning ramifications, uninterrupted lines and termini of the signs being recognized from the number of black-white transitions per scanning period. The arc determined by the width and phase of the scanning pulse and covering a line last scanned within a scanning cycle is stored and compared with the arcs of the lines covered during the next-following scanning cycle for assessing coincidence. The coinciding arcs are used as recognition criteria so that no coincidence for one or more scanning cycle indicate a terminus of a sign, one coincidence per scanning cycle indicates the presence of a non-ramified line and a plurality of coincidences per scanning cycle indicate a ramification. The angular value for the direction of follow-up of the scanning circle is derived from the values of beginning and termination of the coinciding arcs.
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