Touch pad
US8319752B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 30, 2008 |
| Grant date | Nov 27, 2012 |
| Priority date | — |
| Expiry date | Jul 7, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0433
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A touch pad (101) includes transducers (201-204) for receiving acoustic signals resulting from touch events, such as the continuous movement of a fingertip across the surface (105) of the touch pad. The acoustic signals are acquired at different transducer locations in the surface. Signals from different transducers are combined, preferably in antiphase, to improve signal characteristics. The transducer signals are supplied to a stereo analogue to digital converter (407). Phase differences (706) are obtained and compared (703) with phase difference profiles (607) of known location, in order to identify the location of the touch event. An index (606) is used to identify candidate locations to reduce the amount of processing. Interpolation (705) is used to locate the touch event between profile locations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.