Non-alterable magnetic coding
US4639584A · kind A · utility
8Cited by
17References
44Claims
0Family size
Inventors
Key dates
| Filing date | Jul 25, 1985 |
| Grant date | Jan 27, 1987 |
| Priority date | — |
| Expiry date | Jul 25, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/087
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A card having an uninterrupted strip of magnetizable material affixed to the surface of a substrate can carry a machine readable code in the form of a magnetized pattern. By removing alternate magnetized segments, in a column of parallel rifts across the strip, the machines readable code becomes non-alterable, since a uniform, unidirectional magnetization of the remaining material restores the original code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.