METHOD FOR HOLOGRAPHIC IDENTIFICATION OF ARTICLES Russian patent published in 1997 - IPC

FIELD: labels for protection against fake manufacturing and copyright violation. SUBSTANCE: method involves generation of holographic label as sequence of Fourier holograms which are generated by common base reflected wave and orthogonal reflected object waves which are located at same direction angles with respect to base wave. All waves use same picture plane which contains three-dimensional self-correlation images of reflected object waves. Hologram is exposed to wave which is coherent in three-dimensional space. Sum of images of self-correlation object waves is generated along direction of exposition wave with exception of frequencies in three-dimensional angle which depends on final aperture of hologram and its low- frequency noise. Hologram authenticity is judged by absence of cross correlation images of object waves in generated image. EFFECT: increased protection. 7 cl, 6 dwg