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In response to the ever increasing need for new anticounterfeiting methods, a new integrated print-based authentication and security strategy is proposed for the protection of valuable documents and products, based on moire intensity profiles. This strategy combines the advantages of microstructure artistic screening for the halftoning of black-and-white or color images, the application of specially designed mathematical transformations on the microstructure, and the possibility of using non-standard color separation for printing the microstructured image with non-standard custom inks. Using our moire-based method, the overt (or covert) microstructured information from which the halftoned image is composed can be made clearly visible in the form of black-and-white of full-color moire intensity profiles with varying displacements, magnification rates and orientations, generating an attractive, dynamic visual effect which is very difficult to counterfeit
Roger Hersch, Patrick Emmel, Fabien Collaud