The invention relates to a system comprising a series of data carriers, in particular identity cards, papers of value or the like, whereby the data carriers belonging to the system exhibit diffraction structures containing standard information and parts of the series are changed by additional measures in the area of the diffraction structures or combined with other elements and they differ from the rest of the series in optically recognizable fashion, whereby the change in the diffraction structures and/or the combination with other elements convey an esthetic overall impression and the change and/or combination with the other elements cannot be undone without destruction of the diffraction structures.