Patent ID: 7751608
Filing Date: 2010-07-06
Classification: B42D,G07D

Abstract:
1. A method for synthesizing a device being part of an item subject to counterfeiting attempts, said item being selected from a set of security documents and valuable products, where said method is performed by a computing system, where said device comprises a base layer with a base band grating and a revealing layer with a revealing line grating which, upon superposition, produces a moire layer comprising a moire image which depending on a comparison with a reference band moire image, allows acceptance or rejection of said device, the method comprising the steps of: a) laying out by said computing system the revealing line grating located within said revealing layer, b) laying out by said computing system the base band grating located within said base layer, said base band grating comprising in each base band a non-repetitive sequence of base band patterns having shapes derived from elements selected from a set of typographic characters, logos, symbols, signs, line art and graphical elements, where respective layouts of the base band grating, the revealing line grating and the band moire image are related according to a band moire image layout model, said band moire image layout model enabling the of two of said three layouts and obtain the third layout by a computation carried out on said computing system and where said band moire image comprises band moire patterns whose shapes are enlarged and transformed instances of said base band pattern shapes.