DIFFRACTION GRATING FOR CERTIFICATION OF AUTHENTICITY, AND RECORDING BODY PROVIDED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To eliminate such drawbacks of a conventional diffraction grating that pattern, which seems moving, can not be observed all over the pattern when the diffraction grating is simply observed but the whole diffraction grating is reflective and has a simple appearance and that although the diffraction grating is made more complicated, the security against forgery for illegal intention is not necessarily improved. SOLUTION: A seal 3 for certification of authenticity is laminated on a base body such as a card to constitute a recording material 1. The diffraction grating in the seal for certification of authenticity is formed by densely and two-dimensionally arranging unit diffraction grating domains. The diffraction grating selected from a group of diffraction gratings for the arrangement in which the diffraction characteristics are gradually and successively made different is assigned in each unit diffraction grating region while diffraction gratings having similar diffraction characteristics are not arranged in adjacent to each other or in proximity regions.