Optical structures providing dichroic effects
US11675203B2 · kind B2 · utility
3Cited by
31References
25Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2020 |
| Grant date | Jun 13, 2023 |
| Priority date | — |
| Expiry date | Sep 29, 2040 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29D11/0073
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A document, product, or package, such as a banknote, passport or the like comprises structures having dichroic effects that change color with viewing angle in both transmission and reflection. Such structures can be useful as security features that counter the ability to effectively use counterfeit documents, products, packages, etc.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.