公开(公告)号：US20180025198A1

公开(公告)日：2018-01-25

申请号：US15549896

申请日：2016-01-05

Applicant: BYD COMPANY LIMITED

Inventor： Zhengang LI ,  Kunping XU ,  Yun YANG

IPC: G06K9/00

CPC classification number: G06K9/0002

Abstract: The present disclosure provides a fingerprint detection circuit and method. The circuit includes a fingerprint collecting module and a processing module. The fingerprint collecting module includes a plurality of collecting units, and each collecting unit has a regulation voltage and is configured to output a first voltage or a second voltage according to a capacitance value of one of ridge capacitors, a capacitance value of one of ridge capacitors and the regulation voltage. The processing module is configured to amplify the first and second voltages by a predetermined factor, to calculate a difference between the amplified first and second voltages, and to determine whether the difference is greater than or equal to the predetermined threshold. If no, the processing module adjusts at least one parameter, and configures the fingerprint detection circuit using at least one adjusted parameter.

公开(公告)号：US20180299248A1

公开(公告)日：2018-10-18

申请号：US15574053

申请日：2016-06-08

Applicant: BYD COMPANY LIMITED

Inventor： Zhengang LI ,  Kunping XU ,  Yun YANG

IPC: G01B7/28 ,  G06K9/00

CPC classification number: G01B7/28 ,  G06K9/0002

Abstract: The present disclosure provides a method and an apparatus for adjusting an excitation voltage of a fingerprint detection chip and a fingerprint detection chip. The method for adjusting an excitation voltage of a fingerprint detection chip includes: S1, transmitting an excitation signal to the metal ring by the signal transmitting unit, so as to detect a capacitance value of a coupling capacitance formed between the plurality of detection units in the second detection area and the metal ring; or enabling the metal ring grounded, and applying an excitation signal to the plurality of detection units in the second detection area by the signal transmitting unit, so as to detect a capacitance value of a coupling capacitance formed between the plurality of detection units in the second detection area and the metal ring; and S2, adjusting an excitation voltage of the first detection area according to the capacitance value of the coupling capacitance formed between the plurality of detection units in the second detection area and the metal ring.

公开(公告)号：US20180032780A1

公开(公告)日：2018-02-01

申请号：US15549872

申请日：2016-01-05

Applicant: BYD COMPANY LIMITED

Inventor： Zhengang LI ,  Kunping XU ,  Yun YANG

IPC: G06K9/00 ,  H03F3/00

CPC classification number: G06K9/0002 ,  H03F3/005 ,  H03F2200/129

Abstract: A fingerprint detection circuit and an electronic device are provided. The fingerprint detection circuit is configured to apply an excitation signal to a finger so as to generate a finger capacitor, and the fingerprint detection circuit includes: a signal amplifier having a negative input terminal connected with the finger capacitor, a positive input terminal connected with a voltage reference terminal, and an output terminal to output an output voltage according to a capacitance value of the finger capacitor; a capacitor; and a switch unit connected with the negative input terminal and the output terminal of the signal amplifier respectively, and configured to control the capacitor to be connected between the negative input terminal and the output terminal of the signal amplifier, such that the output voltage has a non-linear relationship with the capacitance value of the finger capacitor.

公开(公告)号：US20180032784A1

公开(公告)日：2018-02-01

申请号：US15550844

申请日：2016-01-05

Applicant: BYD COMPANY LIMITED

Inventor： Zhengang LI ,  Kunping XU ,  Yun YANG

IPC: G06K9/00 ,  G06T3/40

CPC classification number: G06K9/0008 ,  G06K9/00 ,  G06K9/00013 ,  G06K9/001 ,  G06T3/4038

Abstract: The present disclosure provides a fingerprint identification method and apparatus. The fingerprint identification method includes obtaining a to-be-identified fingerprint image and extracting first characteristic points of the to-be-identified fingerprint image; determining whether a number of the first characteristic points of the to-be-identified fingerprint image is less than a predetermined threshold: when the number of the first characteristic points of the to-be-identified fingerprint image is less than the predetermined threshold, selecting, a fingerprint template image according to the number of the first characteristic points; extracting second characteristic points in the fingerprint template image matching with the first characteristic points of the to-be-identified fingerprint image; overlapping the fingerprint template image with the to-be-identified fingerprint image according to the first characteristic points of the to-be-identified fingerprint image and the second characteristic points of the fingerprint template image to form an overlapped image; determining a valid coincidence region between the to-be-identified fingerprint image and the fingerprint template image in the overlapped image; and determining whether the to-be-identified fingerprint image matches the fingerprint template image according to the valid coincidence region to generate a matching result and performing fingerprint identification based on the matching result. According to the disclosed method, fingerprint identification with less characteristic points can be realized, thus improving the success rate of the fingerprint identification, and reducing the identification error rate.

公开(公告)号：US20180005000A1

公开(公告)日：2018-01-04

申请号：US15546754

申请日：2016-01-05

Applicant: BYD COMPANY LIMITED

Inventor： Zhengang LI ,  Kunping XU ,  Yun YANG

IPC: G06K9/00

CPC classification number: G06K9/0002 ,  G06K9/001

Abstract: A fingerprint detection circuit and an electronic device are provided. The fingerprint detection circuit is configured to apply an excitation signal to a finger so as to generate finger capacitors, and the fingerprint detection circuit includes: a signal amplifier having a negative input terminal connected with one of the finger capacitors, a positive input terminal connected with a ground terminal, and an output terminal to output an output voltage according to a capacitance value of the one of the finger capacitors; a capacitor connected between the negative terminal and the output terminal of the signal amplifier; a rheostat; and a switch unit connected with the rheostat in series and configured to control the rheostat to be connected with the capacitor in parallel, such that the output voltage has a non-linear relationship with the capacitance value of the one of the finger capacitors.