Method for measuring the movement of an optical pointing device on a work surface
US8368381B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 2012 |
| Grant date | Feb 5, 2013 |
| Priority date | — |
| Expiry date | Apr 19, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/038
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
It is described a method for measuring the movement of an optical pointing device on a work surface, which includes a pixel photo-detector array to pick-up reflected light on the work surface, a window comparator array receiving pixel voltages and providing comparison signals to a processing circuit. Light intensity between neighboring pixels is compared to determine edge direction data, which includes a positive edge for a first pixel voltage smaller than a second pixel voltage by more than a half of a window voltage, a no-edge, with the difference between the pixel voltages smaller than the half of the window voltage, and a negative edge, for which the first pixel voltage is greater than the second pixel voltage by more than the half of the window voltage. Two edge direction data from two successive flash are compared to determine the relative motion of the pointing device on the work surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.