Patent · US Expired

Method of identifying a data carrier

US6179211A · kind A · utility

25Cited by
6References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 8, 1998
Grant dateJan 30, 2001
Priority date
Expiry dateDec 8, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K19/12
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method of identifying a data carrier such as a credit card, benefit card, access control card, identity card or stored value card, carrying data in the form of a plurality of rational number in a sequence, successive numbers having a marker between them, comprises a) measuring the distance from a fixed point on the data carrier to a given part of a marker, b) dividing this distance by the distance between corresponding give parts of successive markers, thereby obtaining a rational number, and c) subtracting this rational number from the number in the sequence adjacent the marker in a given direction, thereby obtaining a further rational number which is capable of identifying the data carrier uniquely.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.