Patent ID: 7982929

Claim:
A method of using a sensing device to read machine-readable coded data, the coded data being arranged in accordance with at least one layout having n-fold rotational symmetry about a center of rotation, where n is at least two, and having mirror symmetry, the layout including: n identical first sub-layouts rotated 1/n revolutions apart about the center of rotation, and, n identical second sub-layouts rotated 1/n revolutions apart about the center of rotation, each second sub-layout being a reflection of a corresponding one of the first sub-layouts, at least one sub-layout including: rotation-indicating data that distinguishes that sub-layout from at least one other sub-layout; and reflection-indicating data that distinguishes the reflection of that sub-layout from the reflection of a corresponding reflected sub-layout, the method comprising the steps of: sensing at least one layout using the sensing device; decoding the coded data of at least one of the sub-layouts of the sensed layout, thereby determining at least the rotation-indicating data of that sub-layout; and using the rotation-indicating data to interpret the meaning of at least some of the coded data.