The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 23, 2010
Filed:
Apr. 29, 2005
Winfried Hoffmuller, Bad Tolz, DE;
Theodor Burchard, Gmund, DE;
Winfried Hoffmuller, Bad Tolz, DE;
Theodor Burchard, Gmund, DE;
Giesecke & Devrient GmbH, Munich, DE;
Abstract
A security element for securing value documents has a first light-polarizing layer that is present at least in some areas and includes a cholesteric liquid crystal material, that selectively reflects light having a predetermined circular polarization, and that selectively reflects light of a firs wavelength range in a first reflection direction and light of a second wavelength range having a second, different reflection direction. A second light-polarizing layer is present at least in some areas and selectively reflects light having the opposite circular polarization to the predetermined circular polarization and selectively reflects light of the first and second wavelength range in the first and second reflection direction, respectively. A semi-transparent filter layer on which the first and second light-polarizing layer are stacked, absorbs light from the visible spectral range and transmits light from the first and/or second wavelength range.