MULTILAYER PROTECTIVE OPTICAL DIFFRACTION DEVICE, A METHOD FOR MANUFACTURING THE SPECIFIED DEVICE, A PROTECTED PRODUCT CONTAINING THE SPECIFIED MULTILAYER PROTECTIVE OPTICAL DIFFRACTION DEVICE Russian patent published in 2021 - IPC B42D25/328 G03H1/00 

FIELD: counterfeit protection.

SUBSTANCE: group of inventions relates to protection against forgery of valuable documents, in particular to a method for manufacturing a multilayer protective optical diffraction device and to a protective device made according to the specified method, as well as to a protected product and a valuable document, each containing the specified protective device. A multilayer protective optical diffraction device contains at least two information-bearing elements; in this case, the first information-bearing element is made in the form of at least one diffraction grating and/or at least one relief hologram with a predetermined first picture distribution of stroke directions, depth and stroke periods in these diffraction gratings and/or relief holograms and with the provision of microcracks located along the strokes over the entire area occupied by these diffraction gratings and/or relief holograms; the second information-bearing element is made in the form of at least one relief hologram of the wallpaper type with a predetermined second picture distribution of stroke directions, depth and stroke periods in these relief holograms of the wallpaper type, while the design of at least one diffraction grating and/or relief hologram with a predetermined first picture distribution of stroke directions, the depth and periods of strokes in the specified diffraction gratings and/or relief holograms of the first information-bearing element differs from the design of at least one relief hologram of the wallpaper type with a predetermined second picture distribution of the directions of strokes, depth and periods of strokes in the specified relief hologram of the second information-bearing element.

EFFECT: expansion of the range of optical instruments.

30 cl, 2 dwg