Optical films for creating unique optical effects
US7298533B2 · kind B2 · utility
14Cited by
5References
42Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 22, 2004 |
| Grant date | Nov 20, 2007 |
| Priority date | — |
| Expiry date | Mar 22, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/722
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An optical layer comprises a sheet of material having a surface. The surface comprises a plurality of optical elements. The optical elements are comprised of microscopic patterns in the surface that cooperate to produce an image. Each of the elements has a focal length. At least some of the focal lengths are significantly different from other focal lengths, such that some portions of the surface appear to be closer to a viewer than other portions of the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.