Label with a diffractive bar code and reading arrangement for such labels
US6927885B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 2002 |
| Grant date | Aug 9, 2005 |
| Priority date | — |
| Expiry date | Sep 6, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/06046
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A label (1) made from a layer composite (15) includes at least one machine-readable diffractive bar code (3) consisting of narrow rectangular fields (4) occupied by the optically active structures and intermediate surfaces (5). The optically active structures which are covered by a reflection layer are embedded between layers of the layer composite (15). The diffractive relief structure used in the diffractive bar code (3) for the fields (4) diffracts and polarizes incident light and scatters the diffracted light into a half-space above the diffractive relief structure. A second diffractive relief structure differs at least in respect of the polarization of the polarizedly backscattered light with respect to the first diffractive relief structure. The second diffractive relief structure can be used for example for field surfaces of a second bar code in the bar code field (9) on the label (1) or for the intermediate surfaces (5). The light which is polarizedly backscattered at the diffractive bar code (3) can be detected by means of one of the known commercially available reading apparatuses for bar codes produced by printing. The bar code produced by printing can be used for indivi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.