Patent · US Expired

Touch screen

US5708460A · kind A · utility

206Cited by
3References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 2, 1995
Grant dateJan 13, 1998
Priority date
Expiry dateJun 2, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/04142
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A touch screen or touch panel wherein there is a monitoring of relative distribution of force via one or more, preferably symmetrically positioned, sensors such as strain gage sensors. The strain gage sensors are positioned such that bending strain on the touch screen, engendered by touch, is detected by the one or more strain gages and accurately measured by an electronic controller, connected to the strain gage(s). The electronic controller, or associated hardware, is programmed to relate relative bending force to a unique position on the screen and is a charge balancing and multiplying analog-to-digital converter which provides accurate position determination, even with very low forces and with very minor differentiation in position related forces. A sum and divide analog-to-digital converter uses charge balancing and integration, with the balance charge coming from the plus and minus sum of the corners (wherein four sensors are positioned at the corners of a square or rectangular display), and the input signal is the difference between two sides of the display panel. This, in effect, results in the input signal being divided by the sum signal and the sum of charge counts over a…

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