Method for the detection of authenticity in a data carrier and apparatus for applying said method
US4650979A · kind A · utility
Inventors
Key dates
| Filing date | Oct 5, 1981 |
| Grant date | Mar 17, 1987 |
| Priority date | — |
| Expiry date | Oct 5, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07F7/086
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention specifies a method for the verification of authenticity in a data carrier (1) by measuring permeability to an electromagnetic radiation in at least one region of the data carrier (1). Permeability is scanned over a regional area of the data carrier by means of a radiation detector (7) first in a calibration operation, in which the radiation intensity is adjusted, then in a reading operation at another position of the data carrier. The output signal of the detector (7) is coded and co-inscribed as additional information in a store of the data carrier with the information data during the initial inscribing of these data. In the reading and authenticity check scanning operation this information is compared with a corresponding additional information stored during the original data inscription.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.