CODING SYSTEMS

摘要

Machine readable coded markings carried on articles to identify various properties of the articles are disclosed. The coded markings are formed integrally of the article in the form of a sequence of areas having contrasting light scattering and reflecting properties incorporated on the article's surface. The areas are arranged in the form of neighboring blocks and empty spaces disposed around and outside of a central target area defined by a sequence of concentric continuous markings, the blocks forming a series of layers containing coded information. Each of the blocks is positioned side-by-side contiguous either with the outermost ring of the target or with a block in a previous layer.