Patent ID: 7728931

Claim:
A security element for securing valuable articles, having a first optically active layer that is present in at least some areas and comprises cholesteric liquid crystal material, and a second optically active layer that is present in at least some areas, the first and the second layer being stacked in an overlap area, characterized in that the first optically active layer selectively reflects light in a first wavelength range having a first direction of circular polarization, the second optically active layer, either itself or, in the overlap area, in coaction with the first optically active layer, selectively reflects light in a second wavelength range having a second direction of circular polarization, that the second optically active layer forms a phase-shifting layer, that the second optically active layer forms a λ/2 layer for light from the first wavelength range and that the second optically active layer is present in the form of characters and/or patterns.