Touch entry using discrete reflectors
US4986662A · kind A · utility
68Cited by
11References
4Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 19, 1988 |
| Grant date | Jan 22, 1991 |
| Priority date | — |
| Expiry date | Dec 19, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0421
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system and apparatus utilizes a source of coherent light located at the focal point of reflecting surfaces oriented to develop parallel beams of light extending over a given area with adjacent sides made to include arrays of light detectors scanned sequentially in a direction away from the source of light so as to detect the shadow cast by an object relative to the reflected light. Alternatively, a photodetector is positioned at the focal point of the reflectors to receive light emitted by individual ones of emitters. Reflecting surfaces are contemplated which simulate a parabolic shape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.