Touch controller
US5008497A · kind A · utility
Inventor
Key dates
| Filing date | Mar 22, 1990 |
| Grant date | Apr 16, 1991 |
| Priority date | — |
| Expiry date | Mar 22, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/045
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A touch controller is presented that comprises a touch sensor employing a resistive membrane, and an analog electronic circuit that accurately measures the touch position and the touch pressure on the sensor. Several variations of the electronic circuit are presented based on the principle of providing a constant current through the touch sensor, measuring the position with a differential amplifier, and measuring the touch pressure at the output of the current regulator. The touch sensors that may be used include resistive coatings such are used in overlays for computer displays, and force-sensing resistors. The circuits are simple, accurate and low-cost, yet provide measurements of the touch position that are fully decoupled from the pressure measurement, without approximation. The result is that the useful range of touch sensitivity is extended to include very light touches, without sacrificing position accuracy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.