Optical touch screen systems using total internal reflection
US8553014B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 2013 |
| Grant date | Oct 8, 2013 |
| Priority date | — |
| Expiry date | Feb 12, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04808
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A touch screen, including a layer of light-transmissive material having an upper surface that is exposed for touch by one or more objects, a plurality of light emitters underneath the upper surface, a first lens assembly for directing light beams emitted by the light emitters into the layer at an angle such that the light beams, when entering the layer, remain confined to the layer by total internal reflection when the light beams are not absorbed by any of the objects touching the upper surface, a plurality of light detectors for detecting light beams and for generating outputs indicating the amounts of light detected, a second lens assembly for directing light beams at a surface of the layer towards the light detectors, and a calculating unit for determining respective one or more locations of the one or more objects touching the upper surface, based on outputs of the light detectors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.