METHOD FOR GENERATING VARIABLE GUILLOCHE PATTERNS, IMPLEMENTING DEVICE AND IDENTITY DOCUMENT COMPRISING SUCH PATTERNS

Generation of one dimensional guilloche patterns able to be affixed on a document, each guilloche pattern being able to encode variable alphanumeric data providing a different appearance to each guilloche pattern, by formatting alphanumeric data to be encoded in the form of a predefined number of data blocks with a predefined size, generating a carrier function having a plurality of parameters, the formatted data blocks forming at least one of the parameters, and modulating the carrier function by the formatted data blocks so as to encode the alphanumeric data graphically, each data block defining a guilloche pattern, the number of data blocks defining the number of guilloche patterns, the carrier function associated with a formatted data block is modulated locally, each datum of the block being encoded locally in the guilloche pattern, by interpolation of a predefined point associated with the carrier function.