| 摘要 |
A surface pattern (10) has two surface portions (11; l2) with microscopically fine, light-diffracting relief structures. The relief structures are in the form of grating structures GS1 or GS2, respectively, which are composed of at least two superimposed gratings G1 and G2, G3 and G4, respectively. The light-diffracting properties of the gratings G1 to G4 are so selected in accordance with various criteria that novel optical effects which cannot be holographically copied can be achieved with the grating structures GS1 and GS2. Such surface patterns are suitable as optical security elements for documents or articles of all kinds as well as packaging foils.
|
