Detecting the locations of a plurality of objects on a touch surface
US9134854B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 2009 |
| Grant date | Sep 15, 2015 |
| Priority date | — |
| Expiry date | Oct 8, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04109
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An apparatus is controlled to detect locations of a plurality of objects on a touch surface of a panel. An input scanner arrangement introduces at least three beams of radiation into the panel for propagation by internal reflection, and sweeps the beams inside the panel across a sensing area, preferably in at least two different principal directions. At least one radiation detector is arranged to receive the beams from the input scanner arrangement while they are swept across the sensing area. A data processor is connected to the radiation detector(s) and operated to identify the locations based on an attenuation of the beams caused by the objects touching the touch surface within the sensing area, the attenuation being identifiable from an output signal of the radiation detector(s). Each output signal may be further processed to generate a transmission signal, by dividing the output signal by a background signal which represents the output signal without any object on the touch surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.