SETT OCH ANORDNING FOR IDENTIFIERING AV DOKUMENT

摘要

A method and device for identifying documents. A multiplicity of machine-readable markings which characteristically modify incident light by diffraction or refraction are applied to the documents, and selected markings are then cancelled out, the remaining markings representing coded information. The markings are of at least two different kinds causing different modification of incident light, and are arranged in a characteristic configuration on the documents. Information about said configuration is stored in an identification device to permit checking of the remaining markings.