Patent · US Expired

Scanning capacitive semiconductor fingerprint detector

US6580816B2 · kind B2 · utility

91Cited by
3References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 8, 2001
Grant dateJun 17, 2003
Priority date
Expiry dateJul 25, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V40/1306
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A scanning fingerprint detection system includes an array of capacitive sensing elements, the array having a first dimension greater than the width of a fingerprint and a second dimension less than the length of a fingerprint. Each of the capacitive sensing elements has first and second conductor plates connected across an inverting amplifier, the conductor plates forming capacitors with the ridges and valleys of a fingerprint of a finger pressed against a protective coating above the array, the inverting amplifier generating a signal indicative of a ridge or valley. Circuitry is provided for scanning the array to capture an image of a portion of fingerprint and for assembling the captured images into a fingerprint image.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.