Secured document, system for manufacturing same and system for reading this document
US6980336B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 2004 |
| Grant date | Dec 27, 2005 |
| Priority date | — |
| Expiry date | Oct 25, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2227/05
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A document includes at least one drawing or data produced, for example, by printing. In addition, this document includes a hologram representing part of the document. The hologram of this document is recorded using a system including a prerecorded or electrically controllable optical modulator in which the image of at least part of the document is recorded. This modulator is designed to be combined with a layer of photosensitive material. A first reference wave illuminates the layer of photosensitive material. A second wave incident on the modulator and giving rise to a third object wave is also transmitted to the layer of photosensitive material in order to interfere with the reference wave in this layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.