Capacitance-based proximity with interference rejection apparatus and methods
US5565658A · kind A · utility
431Cited by
6References
14Claims
0Family size
Assignee
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Key dates
| Filing date | Dec 7, 1994 |
| Grant date | Oct 15, 1996 |
| Priority date | — |
| Expiry date | Dec 7, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/0298
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and method for a capacitance-based proximity sensor with interference rejection. A pair of electrode arrays establish a capacitance on a touch detection pad, the capacitance varying with movement of a conductive object near the pad. The capacitance variations are measured synchronously with a reference frequency signal to thus provide a measure of the position of the object. Electrical interference is rejected by producing a reference frequency signal which is not coherent with the interference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.