Patent · US Expired

Apparatus and method for digitizer sampled point validation

US5245139A · kind A · utility

14Cited by
5References
50Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 18, 1992
Grant dateSep 14, 1993
Priority date
Expiry dateFeb 18, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/045
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus and method for digitizer sampled point validation which determines the contact resistance at a point of contact between the upper and lower layers of the digitizer and compares the contact resistance with a valid range of contact resistances to either accept or reject the sampled point. The apparatus includes an analog drive circuit for driving the digitizer with one of a plurality of drive sources, a switch control logic coupled to the drive circuit for determining which drive source is coupled to the digitizer, an analog-to-digital convertor coupled to the digitizer, and a microcontroller coupled between the analog-to-digital convertor and the switch control logic. The method of the present invention determines the contact resistance, compares the contact resistance with the valid range, and determines and stores the location of the point if the contact resistance is within the valid range.

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