| 摘要 |
FIELD: protection of securities, legal documents, certificates, credit and other information cards from copying and forgery. SUBSTANCE: information card has backing, layer of adhesive, metallized light-reflecting layer with macro- and microrelieves being formed simultaneously on reflecting layer. Microrelief is formed with variable period within range 0.3-20.0 μ in the form of spiral (view A-A) diffraction grating with triangular profile of ruled grooves. Macrorelief is isolated by region 8 without microrelief and ruled grooves have asymmetric triangular profile. Dispersion of directed white light makes it possible for eye of observer to view color effect at small observation angles, unusual alternation of colors and their shape in rainbow spectrum (views B, C) and asymmetry of diffraction pictures as well as to view lusterless macrorelief and its reflecting glitter in certain direction. EFFECT: high degree of protection. 2 cl, 3 dwg |
