FIELD: protection of documents or articles by applying thereon of optically active element or mark for determining of their authenticity.
SUBSTANCE: mark has embossed transparent plastic film for producing of at least one diffracting grid. Embossed surface is covered at least partly with metal layer. Embossed film has first zone capable of producing rainbow effect, when mark is oriented in first position with respect to direction of illumination, and providing elimination of said rainbow effect, when mark is oriented perpendicular to first orientation. Second zone, from which metal layer is removed and layer of dielectric material (ZnS) is applied, is capable of accepting first color, when mark is in first orientation, and second color different from first color, when mark is oriented perpendicular to first orientation.
EFFECT: simplified and reliable checking and increased level of protection of document or article.
12 cl, 6 dwg
