System for real time finger surface pattern measurement
US7184581B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 2001 |
| Grant date | Feb 27, 2007 |
| Priority date | — |
| Expiry date | Apr 19, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V40/1335
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
This invention relates to a system for measuring patterns in finger surfaces, the system comprising an array of sensor electrodes over which the surface is to be moved, and at least one stimulation electrode for providing a varying current or voltage between the stimulation electrode and the number of sensors through the surface. The stimulation electrode is positioned separately from the array of sensor electrodes and the system comprises a generator coupled to the stimulation electrode for applying a current or voltage with a varying amplitude or phase to the surface. The system comprises a measuring unit coupled to the sensor electrodes for, during the application of the current or voltage, measuring the impedance at the sensor electrodes in a time sequence and calculating values of predetermined characteristics of the surface and combining the calculated values for the sensor electrodes over the time sequence for generating a representation of the surface pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.