Touch sensing systems
US9886105B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2014 |
| Grant date | Feb 6, 2018 |
| Priority date | — |
| Expiry date | Feb 15, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0426
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
We describe a touch sensing system projecting light defining a touch sheet above a surface and a camera to capture a touch image of light scattered by a pen intersecting the touch sheet. A signal processor identifies a lateral location of the pen. The pen includes a light source to provide a light signal, and the system also includes two photodiodes to detect the signal from the pen. The touch detection is augmented by modelling the signals received at the photodiodes, dependent on the distance and angle of a pen, and using this to derive a probability of the observed received signals given the pen location determined from the touch sheet. This information can be used, for example, to allocate identities to the pens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.