Patent ID: 8910869
Filing Date: 2014-12-16
Classification: G06K,G07D

Abstract:
1. A method for checking a value document having a security element with several magnetic regions, said magnetic regions having at least one high-coercive magnetic region which contains a high-coercive magnetic material with a first coercive field strength and at least one low-coercive magnetic region which contains a low-coercive magnetic material with a second coercive field strength which is lower than the first coercive field strength and at least one combined magnetic region which contains both the high-coercive and the low-coercive magnetic material, comprising the steps: first, magnetizing the security element by a first magnetic field whose magnetic field strength is greater than the first coercive field strength, so that the magnetization of the high-coercive magnetic material and the magnetization of the low-coercive magnetic material are aligned in a first magnetization direction, then, magnetizing the security element by a second magnetic field whose magnetic field strength is lower than the first coercive field strength but is greater than the second coercive field strength, the second magnetic field being oriented such that the magnetization of the low-coercive magnetic material through the second magnetizing is aligned antiparallel to the first magnetization direction, detecting first magnetic signals of the security element by a first magnetic detector, and detecting second magnetic signals of the security element by a second magnetic detector, before the detection of the second magnetic signals a third magnetic field acting on the security element, wherein the magnetic field strength of the third magnetic field is greater than the second coercive field strength and the third magnetic field is oriented such that the magnetization of the low-coercive magnetic material is aligned by the third magnetic field in a third magnetization direction which is oriented non-antiparallel to the first magnetization direction.