Device and method for checking value documents, in particular banknotes, and value document processing system

Abstract

An apparatus and a corresponding method for checking value documents, involves at least one first sensor configured to detect electromagnetic radiation reflected and/or transmitted by a value document and to convert the radiation into corresponding first sensor signals. At least one second sensor is configured to detect sound waves reflected and/or transmitted by the value document and to convert the sound waves into corresponding second sensor signals, and an evaluation device configured to determine a first area value which characterizes a first area of the value document on the basis of the first sensor signals, to determine a second area value which characterizes a second area of the value document on the basis of the second sensor signals, and to infer a possible identification marking of the value document with a marking ink on the basis of the first and second area value.

Dependencies are inferred from the claim text.