| 摘要 |
FIELD: information technology. ^ SUBSTANCE: control element has a first drawing printed on a first side of the object and having at least a first set of geometrical shapes, and a second drawing printed on a second side of the object. Said second drawing is printed opposite the first drawing when observing the register. The second drawing has at least a second set of geometrical shapes corresponding to the first dot matrix. At least one of the sets of the geometrical shapes has areas which are displaced such that during correct installation of the double-sided printing register, the control element has zones of different density which can be viewed when illuminated and are formed by said displaced areas. ^ EFFECT: protection from forgery through use of a copy machine. ^ 6 cl, 39 dwg |
