摘要 |
Security document, especially a banknote, comprises a support (1) on which an oscillation circuit (5) is mounted. The oscillation circuit comprises a capacitor (C) that has two electrodes (7a) formed from at least two conducting layers, whereby the electrodes are separated by an insulating layer. The invention also relates to a corresponding set of banknotes, whereby different value notes have different resonant frequencies and a method for coding information in which the information is coded as a resonant frequency or resonant frequencies. |