Fingerprint recognition module, display panel and driving method, and display device

A display panel, comprising:

• a fingerprint recognition module, wherein the fingerprint recognition module includes:
• a first electrode layer, including a plurality of first electrodes that are arranged in an array;
• a piezoelectric layer, disposed on a side of the first electrode layer;
• a driving circuit layer, electrically connected to the first electrode layer;
• a second electrode layer, disposed on a side of the piezoelectric layer facing away from the first electrode layer, wherein the second electrode layer includes a plurality of second electrodes that are arranged along a first direction, and one second electrode of the plurality of second electrodes overlaps at least two first electrodes of the plurality of first electrodes;
• a flexible circuit board, bonded and connected to the plurality of second electrodes, wherein in a plane parallel to the first electrode layer, the plurality of second electrodes and the flexible circuit board are arranged along a second direction, and the first direction intersects the second direction;
• and
• a display module, disposed opposite to the fingerprint recognition module, wherein:
• the fingerprint recognition module is disposed on a side of the display module facing away from a light-exiting surface of the display panel,
• the first electrode layer is disposed on a side of the second electrode layer adjacent to the display module,
• a barrier spacer is disposed between adjacent two second electrodes of the plurality of second electrodes,
• the driving circuit layer at least includes a common signal line, and the common signal line is extended along the second direction, and
• the common signal line at least includes a first common signal line, wherein an orthographic projection of the first common signal line on a plane of the first electrode layer at least partially overlaps an orthographic projection of the barrier spacer on the plane of the first electrode layer.

A driving method of a display panel, configured to drive the display panel to perform a touch detection and a fingerprint recognition, comprising:

• providing the display panel, wherein the display panel includes a fingerprint recognition module and a touch-control layer, the fingerprint recognition module including:
• a first electrode layer, including a plurality of first electrodes,
• a piezoelectric layer, disposed on a side of the first electrode layer,
• a second electrode layer, disposed on a side of the piezoelectric layer facing away from the first electrode layer, wherein the second electrode layer includes a plurality of second electrodes, and a barrier spacer is disposed between adjacent two second electrodes of the plurality of second electrodes,
• a flexible circuit board, bonded and connected to the plurality of second electrodes, and
• a driving circuit layer, electrically connected to the first electrode layer, wherein the driving circuit layer includes a plurality of driving circuits, a common signal line, a scanning line, a detection signal line, a power signal line, and a sampling signal line, and a driving circuit of the plurality of driving circuits includes a first transistor, a second transistor, a third transistor, and a storage capacitor, wherein the common signal line at least includes a first common signal line, wherein an orthographic projection of the first common signal line on a plane of the first electrode layer at least partially overlaps an orthographic projection of the barrier spacer on the plane of the first electrode layer;
• determining a touch position of a finger through the touch-control layer, for the touch detection;
• determining a second electrode of the plurality of second electrodes corresponding to the touch position of the finger;
• providing an excitation signal only to the second electrode corresponding to the touch position of the finger, wherein a corresponding first electrode of the plurality of first electrodes is connected to a common potential, and the piezoelectric layer between the second electrode and the first electrode corresponding to the touch position of the finger generates ultrasonic waves;
• and
• performing, by the driving circuit corresponding to the second electrode corresponding to the touch position of the finger, ultrasonic fingerprint recognition, for the fingerprint recognition.