公开(公告)号：US11093090B2

公开(公告)日：2021-08-17

申请号：US16983788

申请日：2020-08-03

Applicant: Fingerprint Cards AB

Inventor： Andreas Larsson ,  Frank Riedijk

IPC: G06F3/044 ,  G06F3/041 ,  G11C11/419 ,  G06K9/00 ,  G06F21/32

Abstract: A fingerprint sensing system comprising a plurality of conductive selection lines; a plurality of conductive read-out lines crossing the selection lines; selection circuitry controllable to provide a selection signal on at least one selected selection line in the plurality of selection lines; a plurality of pixel elements formed at intersections between the selection lines and the read-out lines; a reference signal source configured to provide a reference signal; and read-out circuitry coupled to each read-out line in the plurality of read-out lines and to the reference signal source, the read-out circuitry being configured to acquire a read-out signal via a read-out line connected to a selected pixel element, when the selected pixel element provides the sensing signal; acquire a reference signal from the reference signal source; form a corrected read-out signal for the selected pixel element based on the read-out signal and the reference signal; and provide corrected read-out signals.

公开(公告)号：US10474873B2

公开(公告)日：2019-11-12

申请号：US15806834

申请日：2017-11-08

Applicant: Fingerprint Cards AB

Inventor： Frank Riedijk ,  Wouter Brevet ,  Hans Thörnblom ,  Christer Jansson

IPC: G06K9/28 ,  G06K9/00 ,  G01D5/24

Abstract: A method of determining a representation of a fingerprint pattern of a finger using a fingerprint sensor comprising a two-dimensional measuring arrangement including a plurality of measuring elements, each comprising a finger electrode spaced apart from the finger by a dielectric structure. For each measurement position, the method comprises the steps of: providing a first measuring element configuration with an elongated first measuring arrangement portion having a first principal direction of extension; and a first peripheral measuring arrangement portion; acquiring a first measurement value for the measurement position; providing a second measuring element configuration having an elongated second measuring arrangement portion having a second principal direction of extension; and a second peripheral measuring arrangement portion; and acquiring a second measurement value for the measurement position. The representation of the fingerprint pattern is determined based on the first measurement value and the second measurement value for each of the measurement positions.

公开(公告)号：US09971926B2

公开(公告)日：2018-05-15

申请号：US15484554

申请日：2017-04-11

Applicant: Fingerprint Cards AB

Inventor： Frank Riedijk ,  Hans Thörnblom ,  Daniel Andersson

IPC: G06K9/00

CPC classification number: G06K9/0002 ,  G06K9/00053

Abstract: There is provided a capacitive fingerprint sensing device for sensing a fingerprint pattern of a finger, the capacitive fingerprint sensor comprising: a protective dielectric top layer to be touched by the finger; a two-dimensional array of electrically conductive sensing structures arranged underneath the top layer; readout circuitry coupled to each of the electrically conductive sensing structures to receive a sensing signal indicative of a distance between the finger and the sensing structure, the readout circuitry comprising a plurality of signal amplifiers arranged underneath the array of electrically conductive sensing structures, wherein a number of signal amplifiers is lower than a number of sensing structures; and selection circuitry coupling each of the sensing structures to at least one signal amplifier and configured to select a sensing structure to be coupled to a corresponding signal amplifier. There is also provided a method for controlling a fingerprint sensing device.

公开(公告)号：US20180012053A1

公开(公告)日：2018-01-11

申请号：US15464582

申请日：2017-03-21

Applicant: Fingerprint Cards AB

Inventor： Andreas Larsson ,  Frank Riedijk ,  Hans Thörnblom

IPC: G06K9/00

CPC classification number: G06K9/0002 ,  G06K9/00087

Abstract: The present invention relates to a method of sensing a fingerprint pattern of a finger using a fingerprint sensing device. The method comprising: controlling a group of sensing elements to change a potential of a group of sensing structures comprised in said group of sensing elements; acquiring, in response to said variation in potential, a response signal from a finger detecting circuitry indicative of the capacitive coupling between the group of sensing structures and the finger detecting structure; comparing a variation in the response signal with a predefined threshold value; and providing a signal indicating that a finger is present when the variation in response signal is greater than the threshold value. The invention also relates to a corresponding fingerprint sensing device.