Patent ID: 8181885

Claim:
A method of imaging a coding pattern disposed on a surface of a substrate, said method comprising the steps of: (a) capturing an image of a portion of said coding pattern, said coding pattern comprising: a plurality of target elements defining a target grid, said target grid comprising a plurality of cells, wherein neighboring cells share target elements; a plurality of data elements contained in each cell; and a plurality of tags, each tag being defined by at least one cell, each tag comprising respective tag data encoded by a respective set of said data elements, wherein each cell comprises first and second orthogonal registration symbols encoded by respective sets of data elements, said first registration symbol identifying a first direction component of an orientation, and said second registration symbol identifying a second direction component of said orientation; and (b) sampling and decoding first and second registration symbols contained in said imaged portion; (c) determining, from the decoded registration symbols, the orientation of the layout of the tag data relative to the target grid; and (d) using said determined orientation to sample and decode said tag data.