Surface pattern including light-diffracting relief structures
US5969863A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1998 |
| Grant date | Oct 19, 1999 |
| Priority date | — |
| Expiry date | Sep 3, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S283/902
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A surface pattern has two surface portions with microscopically fine, light-diffracting relief structures. The relief structures are in the form of grating structures GS1 and 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 packing foils.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.