Coding Pattern Comprising Replicated and Non-Replicated Coordinate Data

摘要

A substrate having a coding pattern disposed on a surface thereof. The coding pattern comprises a plurality of contiguous square tags of length l. Each tag comprises x-coordinate data and y-coordinate data. A y-axis is nominally defined as north-south and an x-axis is nominally defined as east-west. A plurality of data elements are contained in each tag, and x- and y-coordinate data are represented by respective sets of data elements. The x-coordinate data comprises a replicated part and a non-replicated part. The y-coordinate data comprises a replicated part and a non-replicated part. The non-replicated parts are represented in a central row and central column of the tag, each being of width q. Any square portion of the coding pattern having a length (l+q) is guaranteed to contain the x-coordinate data and the y-coordinate data for a tag irrespective of whether a whole tag is contained in the portion.