OPTICALLY VARYING DIFFRACTION STRUCTURE AND METHOD OF MAKING SAID STRUCTURE Russian patent published in 2011 - IPC G06K19/16 

FIELD: physics.

SUBSTANCE: diffraction structure has first elements with a grating, which generate open visual information and second elements with a grating which form hidden elements of visual information. The second elements can be placed on those parts of the first elements which do not have a large value for presenting open information. Another version of the present invention is a structure in which second elements alternate on the surface with first elements.

EFFECT: possibility of creating an optically varying diffraction structure with bright latent images.

54 cl, 27 dwg