Method of forgery-protecting a data carrier, a forgery-protected data carrier and apparatuses for handling, processing and monitoring the data carrier
US4929821A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 1987 |
| Grant date | May 29, 1990 |
| Priority date | — |
| Expiry date | Nov 12, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07F7/02
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Methods and apparatuses for forgery security, issuing and monitoring or reducing the value of data carriers such as value cards, entitlement cards, travel tickets, etc., are described, the data being written into a magnetic layer. According to the method, physical authenticating features of the data carrier are evaluated as inhomogeneities in the magnetic layers which carry the data. Suitable data carriers comprise an individual and characteristic inhomogeneity produced, for example, by fluctuations in thickness, discontinuities (13) etc. The second side of the data carrier (1) is provided with an absorbent coating (15) which serves to receive ink sprayed on by an ink jet printer. For reading and/or coding the data carriers which are provided with two magnetic strips (12, 12') independently of the position of the data carriers, there are in an apparatus two reading-writing heads (60, 60') and two pressure applying rollers (61, 61.degree.) disposed in a longitudinally symmetrical relationship and also a station (70) for reversing the data carrier (1). Movable transversely to the direction of movement of the data carrier (1) are an ink jet printer (30) and an optical reading head (40…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.