Capacitive sensing device and method that reduces influence from transient environmental changes
US9626054B2 · kind B2 · utility
Assignees
Inventor
Key dates
| Filing date | May 4, 2015 |
| Grant date | Apr 18, 2017 |
| Priority date | — |
| Expiry date | May 4, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2300/0426
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A capacitive sensing method includes detecting present measured values of plural reference points from plural sensing points; generating a present difference value according to the present measured values of the reference points and current reference measured values; comparing the present difference value with a threshold; detecting present measured values of the sensing points; generating plural position signals of the sensing points according to the present measured values of the sensing points and the current reference measured values; and controlling the output of the position signals according to a reference signal. When the present difference value is greater than the threshold, executing a procedure for refreshing background noise to refresh the current reference measured values. The sensing points are defined by intersected electrodes, configured to form an array, and correspond to the current reference measured values. The reference points are located at the periphery of the array.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.