Capacitance detecting device for fingerprint identification and fingerprint identification apparatus comprising the same
US9679186B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 2016 |
| Grant date | Jun 13, 2017 |
| Priority date | — |
| Expiry date | Jun 24, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/2605
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A capacitance detecting device for fingerprint identification and a fingerprint identification apparatus are provided. The device includes a conductive border; a detecting screen, comprising: a plurality of detecting units, in which each detecting unit includes: a first conductive layer, a second conductive layer, a third conductive layer and a fourth conductive layer; a detecting module, configured to charge a sensing capacitance between the first conductive layer and a finger in contact with the detecting screen and a feedback capacitance between the first conductive layer and the second conductive layer at a sampling stage, to control electric charges of the sensing capacitance and the feedback capacitance to transfer to an integrating capacitance between the third conductive layer and the fourth conductive layer at an integral stage, to measure a voltage variation of the integrating capacitance at the integral stage and to calculate the sensing capacitance according to the voltage variation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.