Touchpad with active plane for pen detection
US5945980A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 1997 |
| Grant date | Aug 31, 1999 |
| Priority date | — |
| Expiry date | Nov 14, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0446
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A touchpad which simulates an active stylus by providing pulses to the entire active plane (making it an active plane), instead of the stylus. This allows a simple, non-active stylus to compress the touchpad to bring the X, Y traces closer to the active plane at the point to be detected. The phase of the pulses applied to the active ground could be chosen to make a stylus look like a finger, or to differentiate it. The pulses are applied synchronously with the standard triangular waveform applied to traces in the trace matrix. The other traces not being sampled at a particular time are truly grounded, and thus are separated from the active plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.