VALUABLE DOCUMENT WITH AN OPTICALLY VARIABLE STRUCTURE (VARIANTS)

摘要

Valuable document comprises a coating in the form of a printed raster that is made up of at least one colour which is different from the colour of the document base. The document also comprises a three-dimensional raster arranged relative to the coating so that the three-dimensional raster is at least partially disposed on the coating, is oriented substantially parallel to lines of the printed raster and together with the coating forms a latent image which is not discernible when the document is viewed at right angle. At least a portion of lines of the three-dimensional raster has an asymmetric cross-section profile with an aspect ratio of not less than 1:1.25, as a result of which the latent image becomes visible in the form of coloured elements or a single-colour region when the viewing angle changes. Changing the viewing direction by 180 degrees without any change in the viewing angle results in a change in the optical density or colour gamut of at least a part of the latent image. The invention enhances the counterfeit protection of a valuable document with an optically variable image and makes it possible for an untrained user to carry out a visual authenticity check.