Microparticle taggant systems
US6647649B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 2001 |
| Grant date | Nov 18, 2003 |
| Priority date | — |
| Expiry date | Dec 11, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2019/06234
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A microparticle taggant having two or more distinguishable marker layers corresponding to a predetermined numeric code. The plurality of particles comprises a plurality of microparticle sets of at least one microparticle, each microparticle set is characterized by a specific marker layer combination different from each other microparticle set, and the combination of microparticle sets employed in said taggant collectively forms the numeric code. Each specific marker layer combination may employ two or more layers. The microparticle sets employed in the taggant may include at least one datum marker layer coded to include place information and at least two value marker layers coded to specify a value within the place, the datum marker layer(s) being readily distinguishable from the value marker layers and functioning to identify an orientation of the value marker layers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.