MACHINE READABLE CODE SYSTEM

摘要

The invention relates to machine readable codes (3), to devices for reading such codes, and to systems for creating such codes. The machine readable code (3) comprises an array of code elements (9) distributed over a conductive layer (28) in accordance with an associated code value. In one embodiment, the code elements are formed over the conductive layer (28) and, in use, are pressed into the surface of the conductive layer to deform the conductive layer. In another embodiment, the code elements (9) are defined by recessed portions of the surface of the conductive layer. A capacitive sensing transducer (13) senses the surface of the conductive layer to generate signals that vary with the distribution of the code elements. The signals are processed to determine the code value associated with the machine readable code (3).