Patent · US Expired

Information card system

US5175418A · kind A · utility

68Cited by
10References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 14, 1990
Grant dateDec 29, 1992
Priority date
Expiry dateDec 14, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K7/10326
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An information card system operating in a non-contact manner comprises an information card including a data storage, a card reader and a card writer. The card writer writes information data, such as an identification code, on the card. The card reader sends an interrogation or response requiring signal to the card, and the card responds thereto witha signal containing its information data. The card has a pair of electrode plates adapted for static coupling with a pair of electrode plates included in the card writer. The card's electrode plates alternatively can act as a dipole antenna. The card additionally has a loop shaped electrode pattern for communicating with the card reader. The loop shape permits the pattern to modulate a magnetic field generated by the reader. The size of the loop shaped electrode pattern permits it to alternatively act as an antenna.

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