| 摘要 |
FIELD: printing.SUBSTANCE: invention relates to checking of value documents having a security element with a plurality of magnetic regions, including a high-coercivity magnetic region. After magnetisation of all magnetic regions in a first direction, all magnetic signals from value document are detected by a first magnet detector. Second magnetisation is then carried out, in which low-coercivity magnetic material is re-magnetised anti-parallel to first magnetisation, but high-coercivity magnetic material remains oriented in first magnetisation direction. Under effect of second magnetic field, second magnetic signals are detected by a second magnet detector. Based on magnet signals, a magnet region of security element is identified as having high-coercivity, low-coercivity, a combined or a soft magnetic region.EFFECT: high reliability when checking value documents.17 cl, 10 dwg |
