HOLOGRAPHIC DEVICE WHICH DETECTS ENCODING ELEMENTS

摘要

FIELD: devices for protection of securities against counterfeit. SUBSTANCE: method involves detection of Fourier holograms by means of moving of point reference wave source from front focal plane of optical system of Fourier transform of object image into infinity. Spherical optical system of Fourier transform is replaced by cylindrical one which has cylindrical lens and optical round cylinder. Hologram is located on reflecting material. EFFECT: increased complexity of unauthorized decoding of information which is stored on hologram due to decreased size of hologram and increased resolution of device, increased level of document authentication. 2 dwg