Hierarchichal optical element sets for machine-read articles
US10691908B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2017 |
| Grant date | Jun 23, 2020 |
| Priority date | — |
| Expiry date | Sep 27, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/06037
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An article includes a substrate with a physical surface, and a hierarchy of parent and child optical element sets embodied on the physical surface, such that a first encoded value represented by the parent optical element set is based at least in part on the visual appearance of a particular optical element in the child optical element set, and a second, different encoded value represented by the particular parent optical element is based at least in part on the visual appearance, and the second encoded value not being decodable from a distance greater than a threshold distance, the first encoded value being decodable from the distance greater than the threshold distance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.