Document marking system employing context-sensitive embedded marking codes
US5467447A · kind A · utility
23Cited by
6References
35Claims
0Family size
Inventor
Key dates
| Filing date | Jul 26, 1991 |
| Grant date | Nov 14, 1995 |
| Priority date | — |
| Expiry date | Jul 26, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/3271
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system for generating documents which, as well as presenting the usual alpha-numeric text information, contain a distinctive marking. The marking scheme of the invention can convey identifying information which, in the event of a document coming into the possession of an unauthorized person, allows a particular copy of a document to be traced to its source. The invention can also be used to distinctively identify each of a number of photocopies made from an original document.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.