Patent · US Active

Optical fingerprint recognition circuit

US11749013B2 · kind B2 · utility

0Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 2021
Grant dateSep 5, 2023
Priority date
Expiry dateMay 23, 2041

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06V40/1318
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

This application provides an optical signal processing circuit and an electronic device, to improve a signal-to-noise ratio of an output signal of a fingerprint sensor, thereby improving a fingerprint recognition rate. The optical signal processing circuit includes a photosensitive device, an amplifier transistor T1, a switch transistor T2, a switch transistor T3, a readout circuit, a control circuit, and a voltage-adjustable power supply. When the optical signal processing circuit is in a compensation reset phase, the voltage of the gate of T1 exactly reaches a level at which the amplifier transistor T1 is turned on. Therefore, when an input voltage and a voltage increment are applied to the gate of T1, a gate-source voltage Vgs of T1 increases, and T1 amplifies an input voltage signal to generate an output signal.

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