Data card reader with async. read=out - scans binary coded numbers designating matrix columns or rows

摘要

The reader allows asynchronous read-out of coded data represented by a matrix of binary markings. The data card (k) is transported parallel to either the rows or columns of the matrix, for detection of the coded data along each successive column or row, together with the code number designating the latter, obtained from a reference line. The code numbers represent each column or row by a modulo 3 binary coding, with a binary (1) marked every three columns or rows and (23, 24, 25) for groups of 3 successive binary states. Alternatively two detectors read two successive binary states, the spacing between the detectors being slightly different to the interval between succesive binary markings.