PROCESS FOR CONVERTING A QUASI-PERIODIC FINE STRUCTURE COMPUTED HOLOGRAM WITH NON-DIVIDED PIXELS INTO A HYBRID STRUCTURE HOLOGRAM, TO OBTAIN A HIGHLY SECURE HOLOGRAPHIC MARK

摘要

The invention relates to a process for converting a quasi-periodic fine structure computed hologram with non-divided pixels into a hybrid structure hologram, to obtain a highly-secure holographic mark intended to be used as means of security and authentication of documents and/or valuable commercial goods. According to the invention, the conversion process consists in decomposing the quasi-periodic fine structure computed with solid pixels into pairs of pixels, some non-exposed pixels and some pixels containing in their turn a hyper-fine periodic structure, a hybrid hologram being obtained thereby. The hologram contains allover its surface encoded information concerning two virtual objects which, when decoded, appear concomitantly, under different angles, the parameters of virtual objects as well as the relating angle therebetween being defined during the design stage and being known only by the customer and the designer.