阅读说明：本技术 指纹识别模组及其驱动方法和电子装置 (Fingerprint identification module, driving method thereof and electronic device ) 是由 刘英明 丁小梁 李秀锋 王鹏鹏 于 2020-01-17 设计创作，主要内容包括：一种指纹识别模组及其驱动方法和电子装置。该指纹识别模组包括接收电极层、压电材料层、第一驱动电极层和第二驱动电极层。接收电极层包括多个接收电极；压电材料层设置在接收电极层的一侧；第一驱动电极层设置在压电材料层远离接收电极层的一侧且包括多个第一驱动电极；第二驱动电极层设置在接收电极层远离压电材料层的一侧且包括多个第二驱动电极,多个第一驱动电极和多个第二驱动电极形成多个驱动电极对,各驱动电极对中的第一驱动电极和第二驱动电极在压电材料层上的正投影至少部分重叠。由此,该指纹识别模组可实现以较低的驱动电压实现对压电材料层的高压驱动或高压激励。(A fingerprint identification module, a driving method thereof and an electronic device are provided. The fingerprint identification module comprises a receiving electrode layer, a piezoelectric material layer, a first driving electrode layer and a second driving electrode layer. The receiving electrode layer comprises a plurality of receiving electrodes; the piezoelectric material layer is arranged on one side of the receiving electrode layer; the first driving electrode layer is arranged on one side, far away from the receiving electrode layer, of the piezoelectric material layer and comprises a plurality of first driving electrodes; the second driving electrode layer is arranged on one side, far away from the piezoelectric material layer, of the receiving electrode layer and comprises a plurality of second driving electrodes, the plurality of first driving electrodes and the plurality of second driving electrodes form a plurality of driving electrode pairs, and orthographic projections of the first driving electrodes and the second driving electrodes in the driving electrode pairs on the piezoelectric material layer at least partially overlap. Therefore, the fingerprint identification module can realize high-voltage driving or high-voltage excitation on the piezoelectric material layer by using lower driving voltage.)

A fingerprint identification module, comprising:

a receiving electrode layer including a plurality of receiving electrodes;

a piezoelectric material layer disposed at one side of the receiving electrode layer;

the first driving electrode layer is arranged on one side, away from the receiving electrode layer, of the piezoelectric material layer and comprises a plurality of first driving electrodes; and

a second driving electrode layer disposed on a side of the receiving electrode layer away from the piezoelectric material layer and including a plurality of second driving electrodes,

wherein the plurality of first drive electrodes and the plurality of second drive electrodes form a plurality of drive electrode pairs, and orthographic projections of the first drive electrodes and the second drive electrodes in each drive electrode pair on the piezoelectric material layer at least partially overlap.

The fingerprint identification module of claim 1, wherein the plurality of receiving electrodes are arranged in an array along a first direction and a second direction, the plurality of first driving electrodes are arranged along the second direction, the plurality of second driving electrodes are arranged along the second direction, each of the first driving electrodes and each of the second driving electrodes are stripe electrodes extending along the first direction, and the first direction intersects the second direction.

The fingerprint identification module of claim 2, wherein an orthographic projection of each of the first driving electrodes and each of the second driving electrodes on the piezoelectric material layer at least partially overlaps an orthographic projection of a plurality of receiving electrodes arranged along the first direction on the piezoelectric material layer.

The fingerprint identification module of claim 3, further comprising:

the driving circuit layer is positioned on one side, far away from the receiving electrode layer, of the second driving electrode layer; and

a plurality of connecting electrodes are arranged on the substrate,

the driving circuit layer comprises a plurality of driving units, each second driving electrode comprises a plurality of through holes, the plurality of connecting electrodes penetrate through the plurality of through holes respectively and electrically connect the plurality of receiving electrodes with the plurality of driving units respectively, and the plurality of connecting electrodes are insulated from the second driving electrodes.

The fingerprint identification module of claim 4, wherein each of said driving units comprises a thin film transistor.

The fingerprint identification module of any one of claims 2-5, further comprising:

an auxiliary structure located on a side of the receiving electrode layer adjacent to the piezoelectric material layer,

the first driving electrodes extend along the first direction and exceed a first edge of the piezoelectric material layer in the first direction, the first driving electrodes are arranged at intervals along the second direction, the auxiliary structure is arranged at least in contact with the first edge, and the auxiliary structure comprises a slope part, wherein the thickness of the slope part is gradually reduced in the direction from the first edge to the direction far away from the center of the piezoelectric material layer.

The fingerprint identification module of claim 6, wherein a slope angle of the ramp portion is less than 60 degrees.

The fingerprint identification module of claim 6, wherein said auxiliary structure comprises:

a main body portion provided in the same layer as the piezoelectric material layer; and

and an overlapping portion connected to the main body portion and located on a side of the first edge of the piezoelectric material layer away from the functional substrate.

The fingerprint identification module of claim 6, wherein the auxiliary structure is disposed along an edge of the piezoelectric material, the auxiliary structure also being disposed in contact with a second edge of the piezoelectric material layer in the second direction.

The fingerprint identification module of any one of claims 1-9, further comprising:

the acoustic wave reflecting layer is positioned on one side, far away from the piezoelectric material layer, of the first driving electrode layers; and

and the insulating layer is positioned between the acoustic wave reflecting layer and the plurality of first driving electrode layers.

The fingerprint identification module of any one of claims 1-10, wherein the material of the piezoelectric material layer comprises polyvinylidene fluoride.

An electronic device comprising the fingerprint identification module according to any one of claims 1-11.

A method for driving a fingerprint recognition module according to any one of claims 1-11, comprising:

applying a driving voltage to the driving electrode pair to drive the piezoelectric material layer corresponding to the driving electrode to emit ultrasonic waves; and

and receiving the ultrasonic waves reflected by the fingerprints by using the piezoelectric material layer and outputting corresponding fingerprint electric signals through the receiving electrode.

The method for driving the fingerprint identification module according to claim 13, wherein applying the driving voltage to the driving electrode pairs to drive the piezoelectric material layers corresponding to the driving electrodes to emit the ultrasonic waves comprises:

applying a first drive voltage to the first drive electrode of the pair of drive electrodes; and

applying a second drive voltage to the second drive electrode of the pair of drive electrodes,

wherein the polarity of the first driving voltage is opposite to the polarity of the second driving voltage.

The driving method of the fingerprint recognition module of claim 14, wherein the absolute value of the first driving voltage is the same as the absolute value of the second driving voltage.

The method for driving a fingerprint recognition module according to claim 14, wherein at a first time, said first driving voltage is a positive voltage and said second driving voltage is a negative voltage; at a second time, the first driving voltage is a negative voltage, and the second driving voltage is a positive voltage.