Projection systems for touch input devices
US8810549B2 · kind B2 · utility
2Cited by
1References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 22, 2010 |
| Grant date | Aug 19, 2014 |
| Priority date | — |
| Expiry date | Mar 30, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04108
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In infrared touch input devices that detect and locate a touch object from the blocking of light paths propagating along the X,Y axes, an ambiguity arises when two touch objects are present. This ambiguity can be resolved by the provision of additional light paths angled to the X,Y axes. The present invention provides projection systems that include a light splitting element for splitting collimated sheet of light into two or more sets of beam paths, thereby providing the additional light paths for resolving the double touch ambiguity. In preferred embodiments the light splitting element is in the form of a prism film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.