Capacitive sense array for detecting passive touch objects and an active stylus
US9658720B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2011 |
| Grant date | May 23, 2017 |
| Priority date | — |
| Expiry date | Aug 19, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04104
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system comprising a sensing device and a capacitive sense array configured to detect a presence of a passive touch object and a stylus where the capacitive sense array receives a transmit signal from the stylus via capacitive coupling. The system further comprising a processing device configured to determine the stylus location on the capacitive sense array based on the transmit signal and to synchronize the stylus to the capacitive sense array. A system further comprises a demodulation block to extract additional data that is modulated into the transmit signal by the stylus. The demodulation block is configured to extract the additional data by amplitude shift keying. The additional data comprises at least one of an applied force value of the stylus tip, a button status data, a battery status data, or a stylus acceleration data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.