METHOD FOR PROTECTION OF SECURITIES AGAINST FORGERY Russian patent published in 2000 - IPC

FIELD: protection of securities against forgery. SUBSTANCE: the method consists in application on the surface or implantation in the volume of material of contrast substance forming an element of protection of securities representing a mark consisting of coding lines, strokes or points. Location of lines, strokes or points of the applied mark, its dimensions and quantity of the applied contrast substance are set by means of a code transformed to a wave signal with base B=2TΔF, where B-signal base, T-signal duration, ΔF-signal frequency band; the signal base is within 10⁴-10⁸ and more. The technical result is associated with the possibility of use of complex codes, providing for application of the mark by a super-low quantity of contrast substance, so that it becomes impossible to change the content of substance in separate elements of the mark with an accuracy required for reproduction. EFFECT: enhanced reliability. 3 cl, 9 dwg