Common mode noise suppression during hovering and proximity detection
US9535545B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2013 |
| Grant date | Jan 3, 2017 |
| Priority date | — |
| Expiry date | Jan 6, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0446
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In one embodiment, a touch sensor includes a touch screen having a plurality of electrodes and a controller. The controller is operable to detect that an object is in proximity to the touch screen by measuring capacitance values from a reference area of the touch screen, determining a reference capacitance value using the measured capacitance values from the reference area, measuring capacitance values from a main area of the touch screen, and suppressing noise from the measured capacitance values of the main area by subtracting the reference capacitance value from the measured capacitance values of the main area of the touch screen. The reference area includes two or more of the plurality of electrodes, and at least one of the electrodes of the reference area is electrically coupled to a voltage reference. The main area includes electrodes of the plurality of electrodes that are not in the reference area.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.