AN APPARATUS FOR THE MANUFACTURE OF INDIVIDUAL HOLOGRAMS TO MAKE DOCUMENTS SECURE

摘要

An apparatus serves the manufacture of holograms from a master hologram of a ground glass screen recorded with one or more wavelengths and one or more reference angles. By means of these, stereoscopic and individual colour holograms can be manufactured in a contact copy process. The apparatus possesses a radiation source for laser irradiation (6, 8) for the irradiation of a master (H2) and a film (7) . So that holograms which contain different information can be manufactured in a simpl e manner, a modulation apparatus, in particular an LCD, is provided for the modulation of the coherent radiation (6, 8) (Fig. 2).