Patent ID: 7667894
Filing Date: 2010-02-23
Classification: B42D,G02B

Abstract:
1. A security element for securing value documents, having a first light polarizing layer that is present at least in some areas and comprises a cholesteric liquid crystal material, that selectively reflects light having a predetermined circular polarization, and that selectively reflects light of a first wavelength range in a first reflection direction and light of a second wavelength range in a second, different reflection direction, a second light polarizing layer that is present at least in some areas and that selectively reflects light having the opposite circular polarization to the predetermined circular polarization, and that selectively reflects light of the first and second wavelength range in the first and second reflection direction, respectively, and a semi-transparent filter layer on which the first and second light polarizing layer are stacked, the filter layer at least partially absorbing light from the visible spectral range and transmitting light from at least one of the first and second wavelength range.