Flexible display panel and flexible display device

Patent metadata

Field	Value
Publication number	US-11244587-B2
Application number	US-201916719588-A
Country	US
Kind code	B2
Filing date	Dec 18, 2019
Priority date	Jun 20, 2019
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

A flexible display panel and a flexible display device are described. The flexible display panel includes a bending region, a non-bending region. A number of deformation detection units are disposed in the bending region. The deformation detection units each includes a first electrode, a piezoelectric (PZT) material function layer and a second electrode which are sequentially stacked in a direction perpendicular to a light-emitting surface of the flexible display panel. The density of the PZT units and PZT function layer thickness may vary depending on their distance from the bending axis.

First claim

What is claimed is:

1. A flexible display panel, comprising:
a bending region capable of bending a long a bending axis;
a non-bending region; and
at least one deformation detection unit disposed in the bending region,
wherein each of the at least one deformation detection unit comprises a first electrode, a piezoelectric material function layer, and a second electrode, wherein the first electrode, the piezoelectric material function layer, and the second electrode are sequentially stacked along a direction perpendicular to a light-emitting surface of the flexible display panel;
wherein the bending region comprises a display region and a non-display region, and wherein the at least one deformation detection unit is disposed in the non-display region;
wherein a number of the at least one deformation units is greater than or equal to 2, the at least one deformation detection unit comprises a plurality of first deformation detection units and a plurality of second deformation detection units, wherein in an extending direction of the bending axis of the bending region, the display region of the bending region has a first side and a second side opposite to the first side, wherein the plurality of first deformation detection units are disposed on the first side of the display region and the plurality of second deformation detection units are disposed on the second side of the display region, wherein in the direction perpendicular to the extending direction of the bending axis, the plurality of first deformation detection units are arranged alternately with the plurality of second deformation detection units.

2. The flexible display panel of claim 1 , wherein the bending axis extends along a first direction, the flexible display panel is bent towards the bending axis along a second direction to form the bending region, wherein the first direction is perpendicular to the second direction; and
wherein one or more deformation detection units among the at least one of deformation detection unit are located on the bending axis.

3. The flexible display panel of claim 2 , wherein the at least one deformation detection unit comprises a first deformation detection unit and a second deformation detection unit, the first deformation detection unit is closer to the bending axis than the second deformation unit, and a size of the first deformation detection unit is greater than a size of the second deformation detection unit.

4. The flexible display panel of claim 2 , wherein the at least one deformation detection unit comprises two neighboring deformation detection units spaced apart by a first gap in the second direction and another two neighboring deformation detection units spaced apart by a second gap in the second direction, the first gap is closer to the bending axis than the second gap and is less than the second gap.

5. The flexible display panel of claim 2 , wherein the at least one deformation detection unit comprises a first deformation detection unit and a second deformation detection unit, the first deformation detection unit is closer to the bending axis than the second deformation unit, a thickness of the piezoelectric material function layer of the first deformation detection unit is greater than a thickness of the piezoelectric material function layer of the second deformation detection unit.

6. The flexible display panel of claim 2 , further comprising: a first driving signal line and second driving signal lines;
wherein the at least one deformation detection unit comprises deformation detection unit groups arranged in the second direction, wherein the deformation detection unit groups are in one-to-one correspondence with the second driving signal lines, and wherein the plurality of deformation detection units is arranged in the first direction in each of the deformation detection unit groups,
wherein the first electrodes of the plurality of deformation detection units are connected to the first driving signal line,
wherein the second electrodes of the plurality of deformation detection units in each of the deformation detection unit groups are connected to one of the second driving signal lines.

7. The flexible display panel of claim 6 , wherein the deformation detection unit groups comprise a first deformation detection unit group and a second deformation detection unit group, the first deformation detection unit group is closer to the bending axis than the second deformation detection unit group, and a number of deformation detection units in the first deformation detection unit group is greater than a number of deformation detection units in the second deformation detection unit group.

8. The flexible display panel of claim 1 , wherein a thickness of the piezoelectric material function layer is within a range of 0.52.5 μm.

9. The flexible display panel of claim 1 , further comprising:
a base substrate, a drive circuit layer, a light-emitting unit layer, and an encapsulation layer, wherein the drive circuit layer, the light-emitting unit layer, and the encapsulation layer are sequentially stacked on the base substrate in a direction perpendicular to a light-emitting surface of the flexible display panel;
wherein the drive circuit layer comprises: an active layer, a gate insulating layer, a gate metal layer, a first interlayer insulating layer, a capacitor metal layer, a second interlayer insulating layer, a source/drain metal layer, and a passivation layer which are sequentially stacked on the base substrate;
wherein the light-emitting unit layer comprises a pixel definition layer, which defines a plurality of organic light-emitting units, wherein each of the plurality of organic light-emitting units comprises a third electrode, a light-emitting function layer, and a fourth electrode sequentially stacked on the drive circuit layer;
wherein the first electrode is arranged on a same layer as one of: the gate metal layer, the capacitor metal layer, the source/drain metal layer, a metal layer in which the third electrode is located, and a metal layer in which the fourth electrode; and the second electrode is arranged on a same layer as one of: the gate metal layer, the capacitor metal layer, the source/drain metal layer, the metal layer in which the third electrode is located, and the metal layer in which the fourth electrode, wherein the first electrode and the second electrode are in different layers, and the first electrode is closer to the base substrate than the second electrode.

10. The flexible display panel of claim 9 , further comprising a drive IC, wherein the drive IC is configured to provide a light-emitting driving signal for the plurality of organic light-emitting units; and
wherein the drive IC is further configured to provide a first driving signal and second driving signals.

11. A flexible display device, comprising a flexible display panel, wherein the flexible display panel comprises:
a bending region comprising a bending axis;
a non-bending region; and
at least one deformation detection unit disposed in the bending region, wherein each of the at least one deformation detection unit comprises a first electrode, a piezoelectric material function layer, and a second electrode, wherein the first electrode, the piezoelectric material function layer, and the second electrode are sequentially stacked along a direction perpendicular to a light-emitting surface of the flexible display panel;
wherein the bending axis extends along a first direction, wherein the flexible display panel is bent towards the bending axis along a second direction to form the bending region, wherein the first direction is perpendicular to the second direction;
wherein one or more deformation detection

Assignees

• Shanghai Tianma Am Oled Co Ltd

Inventors

• Ouyang Junting
• Lin Baiquan
• Xi Kerui
• Kong Xiangzi

Classifications

• G09G3/3275

  Details of drivers for data electrodes · CPC title

• G09G2340/14

  Solving problems related to the presentation of information to be displayed · CPC title

• G09G2300/043

  Compensation electrodes or other additional electrodes in matrix displays related to distortions or compensation signals, e.g. for modifying TFT threshold voltage in column driver · CPC title

• G09G3/035

  for flexible display surfaces · CPC title

• G06F1/1652

  the display being flexible, e.g. mimicking a sheet of paper, or rollable · CPC title