Mutual capacitance measurement in a multi-touch input device
US8542215B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 2011 |
| Grant date | Sep 24, 2013 |
| Priority date | — |
| Expiry date | Nov 10, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04104
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Systems and methods for determining multiple touch events in a multi-touch sensor system are provided. The system may include a capacitance measurement unit, a pulse drive unit, and a touch sensor having a plurality of nodes and a plurality of electrodes comprising at least two sets of electrodes. The method may include connecting a first electrode in a first set to the capacitance measurement unit, the pulse drive unit driving a voltage or current pulse onto a second electrode in a second set of electrodes. The method may further include the capacitance measurement unit measuring the mutual capacitance at a node corresponding to the first and second electrodes. The method may include comparing the measured mutual capacitance at the node with a previously measured mutual capacitance for the node, and reporting that the node has been touched if there has been a deviation from the previously measured mutual capacitance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.