Giesecke+devrient Currency Technology Gmbh

Julia Danhof

Wolfgang Deckenbach

Wolfgang Rauscher

Martin Clara

Thomas Happ

Ulf Ehrhardt

Henning Geiseler

A sensor for verifying value documents and designed to determine the luminescence time constant of a value document that is moved past the sensor for verification purposes, and the provision of a velocity correction of the luminescence time constant of the value document in the sensor. The relative movement between the value document and the sensor causes movement effects, resulting in a distortion of the intensity curve from which the luminescence time constant is derived. The luminescence time constant is corrected using a sensor-specific corrective factor ascertained for the velocity of the movement of the value document during the verification process. For this purpose, different sensor-specific corrective factors are used for different examples of sensors that are nominally identical in design and are part of the same sensor production series.

Sensor for verifying value documents

A sensor and a method for checking value documents are provided, each having a luminescent sheet-like substrate and a luminescent feature applied to a partial surface of the substrate, and to a value document processing apparatus. From the spectral vectors obtained for a plurality of measurement points and characterizing the intensity of the luminescent radiation of the value document detected in at least two spectral ranges, substrate intensity values and feature intensity values are determined, based on which a pure substrate mask is determined, which contains only those measurement points which reliably lie outside the feature. From the spectral vectors of the measurement points contained in the pure substrate mask, a mean substrate vector is determined, based on which corrected substrate intensity values and corrected feature intensity values and/or a spectral signature of the substrate and/or of the feature are or is, respectively, determined from the spectral vectors.

Sensor and method for checking value documents, in particular bank notes, and value document processing apparatus

A method and a sensor for checking documents are provided in which the same detector is used for a remission measurement and a luminescence measurement of the value document. The remission measurement value being detected during the illumination of the value document with an excitation light used for luminescence excitation, and the luminescence measurement value after switching off the illumination. In order to reduce a distortion of the remission measurement value by the luminescence, a spectral detection filter is incorporated into the detection ray path, which has a transmission of at least 0.5% in the spectral region of the excitation light. The increased transmission of the spectral detection filter achieves that the excitation intensity impinging on the detector far exceeds the luminescence intensity occurring simultaneously with the excitation and thus reduces the mentioned distortion.

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Munich, Georgia

Julia Danhof