Encoded data card reading system

摘要

A data structure is disclosed encoded on the surface of an object comprising a series of block data regions with each of the block data regions including: an encoded data region containing data to be decoded in an encoded form; a series of clock marks structures located around a first peripheral portion of the encoded data region; and a series of easily identifiable target structures located around a second peripheral portion of the encoded data region. The block data regions can further include an orientation data structure located round a third peripheral portion of the encoded data region. The orientation data structure can comprises a line of equal data points along an edge of the peripheral portion. The clock marks structures can include a first line of equal data points in addition to a substantially adjacent second line of alternating data points located along an edge of the encoded data region. The clock mark structures can be located on mutually opposite sides of the encoded data region. The target structures can comprise a series of spaced apart block sets of data points having a substantially constant value of a first magnitude except for a core portion of a substantially opposite magnitude to the first magnitude. The block sets can further includes a target number indicator structure comprising a contiguous group of the values of the substantially opposite magnitude. The data structure is ideally utilized in a series of printed dots on a substrate surface.