Self-calibrating variable pressure touch key system employing transducers subject to parameter drift
US5345807A · kind A · utility
55Cited by
8References
23Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 8, 1993 |
| Grant date | Sep 13, 1994 |
| Priority date | — |
| Expiry date | Jun 8, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/975
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pressure sensitive touch pad system, for example employing variable capacitance touch pads, employs low cost transducers subject to parameter drift and periodically (e.g. once each second) re-calibrates each touch pad. The periodic re-calibration allows a low cost transducer to be used for multi-point operation, as well as for simple on/off operation, such as for function selection. One application is to provide different slew rates for setting a data entry indicator, for example indicating the value of an appliance function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.