CODING PATTERN COMPRISING NON-REPLICATED COORDINATE DATA SYMBOLS

摘要

A substrate having a coding pattern disposed thereon or therein. The coding pattern comprises a plurality of square tags of length l identifying two-dimensional location coordinates. Each tag comprises: a plurality n1 of x-coordinate data symbols encoding a respective (n2, k) Reed-Solomon code for an x-coordinate; a plurality n1 of y-coordinate data symbols encoding a respective (n2, k) Reed-Solomon code for a y-coordinate; a number z of the x-coordinate data symbols positioned in a central column of width q in each tag with a remaining (n1−z) x-coordinate data symbols distributed evenly on either side of the central column; and a number z of the y-coordinate data symbols positioned in a central row of the tag of width q with a remaining (n1-z) y-coordinate data symbols distributed evenly above and below the central row. Any square portion of the coding pattern of length (l+q) is guaranteed to contain at least (n1+z)/2 data symbols from each of the Reed-Solomon codes.