FIELD: production of optically diffraction protective elements.
SUBSTANCE: the invention is pertaining to production of optically diffraction protective element. The protective element with a sample formed out of the separated surfaces and having the form of a laminated structure used for notarization of authenticity of a document contains, at least, a transparent protective layer, a transparent varnished layer and an adhesive layer. The separated surfaces of the sample consist of the background surfaces and elements of the sample. At that in the field of the background surfaces the varnished layer is formed smooth and even and in the field of elements of the sample the relief structures with the definite optically effective depth "h" are formed in the varnished layer. The background surfaces for the light illuminating a laminated serve as the even reflecting planes and the relief structures are two-dimensional diffraction gratings, which are formed out of the bas gratings with the periods (dx;dy) and the periods (dx;dy) are smaller, than the given limiting wavelength (λ) in the shortwave part of the spectrum of the visible light so, that elements of the sample absorb and disperse the illuminating light. At that in each relief structure the ratio of the absorbed and the dispersed light is given and depends on the given optical effective depth (h) in the relief structure. Thus the invention ensures a high protection of an element against its reproduction by copiers.
EFFECT: the invention ensures a high protection of an element against its reproduction by copiers.
25 cl, 9 dwg
