Patent · US Expired

Graphics tablet using a permuted trace ordering scheme

US4806918A · kind A · utility

7Cited by
9References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 24, 1987
Grant dateFeb 21, 1989
Priority date
Expiry dateApr 24, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/047
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A graphics tablet is presented which has an x-y grid of wire traces embedded on it. Drive wires are coupled to the trace wires in both the x-direction and the y-direction. When a stylus is placed in contact with the graphics tablet, the location of a sector of the graphics tablet where the stylus contacts the graphics tablet may be determined by sequentially placing a signal on each drive wire and measuring the strength of the signal received by the stylus. The closer the stylus is to a particular trace, the stronger the signal which is received by the stylus from the drive wire coupled to that trace. The identity of a plurality of drive wires in the x-direction and a plurality of wires in the y-direction with the strongest received signal can be used to determine a unique address for the location of the sector of the graphics tablet where the stylus contacts the graphics tablet.

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