Giesecke & Devrient Gmbh

Technische Hochschule Rosenheim

Ulrich Schanda

Bernd Wunderer

Jürgen Schützmann

Jan Domke

Klaus Thierauf

Lukas Löffler

Heinz Hornung

Hans-Uwe Richter

J&uuml;rgen Sch&uuml;tzmann

Horst Dötsch

Carsten Holthaus

Alexei Trifonov

Sebastian Hirschmüller

Zuzana Giertlová

The invention concerns a device and a method for examining magnetic properties of objects, in particular of sheet material such as for example bank notes. Therein the invention proceeds from a device and a method for examining magnetic properties of objects with a magneto-optical layer having magnetic domains, the optical properties of the magneto-optical layer being influenced by the magnetic properties of the object to be examined, at least one light source for the generation of light incident upon the magneto-optical layer, and at least one sensor for the reception of light which is transmitted and/or reflected by the magneto-optical layer, with a magnetic filed in the area of the magneto-optical layer which extends substantially parallel to the surface of the magneto-optical layer.

Device and method for examining magnetic characteristics of objects

A method and apparatus for recognizing foreign material (), in particular adhesive objects, glue or joints, on or in bank notes (), including detecting the thermal radiation () emanating from at least a partial area of the bank note (): and recognizing foreign material () located on the bank note () on the basis of the detected thermal radiation (). The invention is especially suitable for recognizing adhesive objects, in particular adhesive tape and joints, on bank notes since areas of a bank note with adhesive tape or joints differ very distinctly in their thermal properties from other areas of the bank note without adhesive tape.

Method and apparatus for recognizing foreign material on bank notes

Devices and methods for investigating the magnetic properties of objects

The invention relates to a method for verifying thickness modulations, in particular watermarks, in or on sheet material. To diminish the influence of disturbances from the surroundings and reduce the adjustment effort during production and maintenance of corresponding measuring systems, the sheet material is subjected to sound, in particular ultrasound, the sound transmitted through the sheet material and/or reflected on the sheet material is measured at a plurality of places on the sheet material, at least one value characteristic of the transmitted and/or reflected sound is generated for each of the places, and the thickness modulations are verified by comparing the values with predetermined reference values.

Verification of thickness modulations in or on sheet-type products

A method for determining structural inhomogeneities in sheet material including exposing sheet material to ultrasonic waves, measuring ultrasonic waves transmitted through the sheet material and ultrasonic waves reflected from the sheet material at a plurality of predetermined portions located linearly along at least one track disposed on the sheet material and producing at least one value characteristic based on at least the transmitted or reflected ultrasonic waves from each of the predetermined portions on the at least one track. The method further includes forming a first mean based on the at least one value characteristic and a second mean based on the first mean to determine the structural inhomogeneities in the sheet material representative of the at least one track.

Method for determining structural inhomogeneities in sheet material

Device for examining sheet-like articles using ultrasound

Device and process for determining the stiffness of sheet-like articles

Growing community of inventors

Holzkirchen, Germany

Ulrich Schanda