Capacitive fingerprint sensor and the panel thereof
US7663380B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 2007 |
| Grant date | Feb 16, 2010 |
| Priority date | — |
| Expiry date | Jun 26, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V40/1306
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A capacitive fingerprint sensor comprises a fingerprint capacitor, a reference capacitor, a first transistor, a second transistor, a third transistor and a fourth transistor. The fingerprint capacitor CF has a capacitance that is either a valley capacitance CFV or a ridge capacitance CFR. The reference capacitor CS has a capacitance CS, and CFV<CS<CFR. The first transistor is configured to precharge the reference capacitor. The second transistor is configured to precharge the fingerprint capacitor. The third transistor is configured to redistribute the charges of the reference capacitor and fingerprint capacitor. The fourth transistor is configured to output the voltage of the reference capacitor after redistribution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.