Item comprising a barcode with an electromagnetic signature

A method for the identification, authentication, or traceability of a set of security documents, comprising:

• providing a set of at least two items, notably documents, each having an optical code, notably a barcode, which is neither connected nor coupled to any electronic chip that may be carried by the item, the optical codes appearing to encode the same information for the same optical reader of optical codes, but having different respective electromagnetic signatures, the electromagnetic signatures being unique to each of the items;
• optically reading the optical code, and
• reading an electromagnetic signature of the optical code.

A method for the fabrication of a set of at least two items, notably documents, each having an optical code, notably a barcode, which is neither connected nor coupled to any electronic chip that may be carried by the item, the optical codes appearing to encode the same information for the same optical reader of optical codes, but having different respective electromagnetic signatures, the electromagnetic signatures being unique to each of the items, the method comprising:

• generating a preliminary optical code relating to the item and encoding information readable by the optical reader, and
• generating at least one modification of the preliminary optical code, which, without affecting the reading of the information decoded by optical reading of the optical code, modifies its electromagnetic signature.

A method for providing traceability of an item, comprising:

• providing a set of at least two items, notably documents, each having an optical code, notably a barcode, which is neither connected nor coupled to any electronic chip that may be carried by the item, the optical codes appearing to encode the same information for the same optical reader of optical codes, but having different respective electromagnetic signatures, these signatures being unique to each of the items;
• wherein an optical reading of the optical code and an electromagnetic reading of the optical code are carried out and information representative of the electromagnetic signature of the optical code is recorded, or the information read by the optical reader is recorded, the information representative of the electromagnetic signature being preferably recorded in correspondence with the information read by the optical reader.

A device for the identification, authentication, or traceability of a set of at least two items, notably documents, each having an optical code, notably a barcode, which is neither connected nor coupled to any electronic chip that may be carried by the item, the optical codes appearing to encode the same information for the same optical reader of optical codes, but having different respective electromagnetic signatures, the electromagnetic signatures being unique to each of the items, the device comprising:

• an optical reader for reading an optical code encoding information readable by the optical reader, and
• an electromagnetic reader for reading an electromagnetic signature of the optical code, and
• means for comparing information resulting from the electromagnetic reading of the optical code with reference information.