Security device
US6903850B2 · kind B2 · utility
36Cited by
19References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 27, 2001 |
| Grant date | Jun 7, 2005 |
| Priority date | — |
| Expiry date | Jun 27, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2250/42
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A security device has a substrate formed with a surface relief defining an optically variable effect generating structure. At least two different reflection enhancing materials are provided on, or on the same side of, substrate with respect to the surface relief, whereby the optically variable effect can be viewed against a background defined by the reflection enhancing materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.