Patent · US Expired

Coordinate determining device and method of determining X-Y coordinate position

US4806708A · kind A · utility

8Cited by
1References
45Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 25, 1988
Grant dateFeb 21, 1989
Priority date
Expiry dateJan 25, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/046
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A coordinate determining tablet and method for determining an X-Y coordinate position using electromagnetic induction, including a plurality of conductive wires mounted on an insulating plate such that the wires are formed in a parallel return winding pattern displaced from each other by an interval; one end of the conductive wires forming the return are connected to a common conductive wire, while the other end of the conductive wires are each connected to one terminal of a switch provided for each parallel winding; the other terminals of the switches are connected alternately to three common conductive wires; the switches are arranged in a number of groups so as to simultaneously turn on and off groups of parallel winding patterns at a predetermined interval. The coordinate determining method includes inducing a current in a cursor, sequentially turning on and off the switches in the groups, adding together the signals induced in the conductive wires, discriminating and comparing the signals, and determining an absolute position of the cursor on the coordinate plane.

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