Apparatus, Method and Assembly for Checking Value Documents, in Particular Bank Notes, and Value-Document Processing System

A method for checking value documents, having the following steps:

• using a sensor for capturing an electromagnetic radiation transmitted by a value document and for generating corresponding transmission signals;
• using an evaluation device for checking whether the value document has a foreign object taking into account the transmission signals generated by the sensor;
• wherein the evaluation device is configured for
• ascertaining an edge course of the value document on the basis of the transmission signals;
• approximating a rectangle to the edge course of the value document;
• checking whether the value document has a foreign object on a basis of any differences between the edge course of the value document ascertained from the transmission signals and the rectangle approximated to the edge course of the value document.

An assembly for checking value documents comprising:

• a sensor for capturing an electromagnetic radiation transmitted by a value document and for generating a transmission image of the value document comprising transmission signals corresponding to the electromagnetic radiation transmitted by the value document, and
• an evaluation device for checking whether the value document has a foreign object taking into account the transmission signals;
• the evaluation device is configured for
• ascertaining an edge course of the value document on the basis of the transmission signals;
• approximating a rectangle to the edge course of the value document;
• checking whether the value document has a foreign object on a basis of any differences between the edge course of the value document ascertained from the transmission signals and the rectangle approximated to the edge course of the value document.