Touch-control display panel and display device, and driving method of display panel

• US 10,191,592 B2
• Filed: 03/31/2017
• Issued: 01/29/2019
• Est. Priority Date: 10/26/2016
• Status: Active Grant

• Current Assignee: Tianma Microelectronics Company Limited, Xiamen Tianma Micro-Electronics Co., Ltd.
• Original Assignee: Tianma Microelectronics Company Limited, Xiamen Tianma Micro-Electronics Co., Ltd.
• Inventors: Zhuang, Zhilong, Huang, Jiancai, Xu, Yumin
• Primary Examiner(s): Amadiz, Rodney
• Application Number:
  US15/475,278
• Publication Number:
  US 20170205960A1
• Time in Patent Office: 669 Days
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A display panel includes a plurality of touch electrodes disposed on a first substrate, and a second pressure sensing electrode disposed on a second substrate facing the first substrate and in a grid-shape. The plurality of touch electrodes are used for touch position detection in a touch position detection period, and at least certain number of the plurality of touch electrodes are multiplexed as first pressure sensing electrodes in a touch force detection period. The orthogonal projection of the first pressure sensing electrodes on the second substrate is at least partially overlapped with the second pressure sensing electrode. Further, in the touch force detection period, the first pressure sensing electrodes and the second pressure sensing electrode are used together to detect a touch force applied on the display panel.

Claims

1. A display panel, comprising:

a plurality of touch electrodes disposed on a first substrate, wherein the plurality of touch electrodes are used for touch position detection in a touch position detection period, and at least certain number of the plurality of touch electrodes are multiplexed as first pressure sensing electrodes in a touch force detection period; and

a second pressure sensing electrode disposed on a second substrate facing the first substrate and in a grid-shape, wherein orthogonal projection of the first pressure sensing electrodes on the second substrate is at least partially overlapped with the second pressure sensing electrode,

wherein, in the touch force detection period, the first pressure sensing electrodes and the second pressure sensing electrode are used together to detect a touch force applied on the display panel,

the second pressure sensing electrode includes grid lines and grid openings surrounded by the grid lines, and

orthogonal projections, on the first substrate, of at least certain number of the grid openings in the second pressure sensing electrode overlap with corresponding first pressure sensing electrodes disposed on the first substrate.

2. The display panel according to claim 1, wherein:

in an image display period, the plurality of touch electrodes are multiplexed as a common electrode.

3. The display panel according to claim 1, wherein:

the second pressure sensing electrode is made of indium tin oxide (ITO).

4. The display panel according to claim 1, wherein:

a sum S₁ of areas of the grid openings satisfies a predetermined condition as;

S₁/S₀>

60%,

wherein S₀ is an area of a plate electrode having a same contour as the second pressure sensing electrode.

5. The display panel according to claim 1, wherein:

an area S₃ of grid openings directly facing a first pressure sensing electrode satisfies a second predetermined condition as;

S₃/S₄<

1−

C_m/(τ

α

C₀),

wherein S₄ is an area of the first pressure sensing electrode, C_m is a capacitance threshold, τ

is a capacitance attenuation coefficient, and C₀ is a capacitance value between the first pressure sensing electrode and a hypothetical electrode, wherein the hypothetical electrode is a plate electrode in a layer same as the second pressure sensing electrode and having a same contour as the first pressure sensing electrode.

6. The display panel according to claim 1, wherein:

an area S₃ of grid openings directly facing a first pressure sensing electrode satisfies a second predetermined condition as;

S₃/S₄<

66.7%,

wherein S₄ is an area of the first pressure sensing electrode.

7. The display panel according to claim 1, wherein:

an area of a grid opening in the second pressure sensing electrode directly facing a first pressure sensing electrode is smaller than an area of a grid opening in the second pressure sensing electrode not directly facing a first pressure sensing electrode.

8. The display panel according to claim 1, wherein:

the second substrate further includes a black matrix region, and the grid lines are within the black matrix region.

9. The display panel according to claim 1, wherein:

the first pressure sensing electrodes are disposed on one side of the first substrate facing the second substrate; and

the second pressure sensing electrode is disposed on one side of the second substrate facing away from the first substrate.

10. The display panel according to claim 9, further including:

a transparent elastic material layer disposed between the first pressure sensing electrodes and the second pressure sensing electrode.

11. The display panel according to claim 10, wherein:

the transparent elastic material layer is disposed between the second pressure sensing electrode and the second substrate.

12. The display panel according to claim 9, wherein:

the first substrate is an array substrate; and

the second substrate is a color film substrate.

13. A display device comprising the display panel according to claim 1.

14. A display panel 4, comprising:

a plurality of touch electrodes disposed on a first substrate, wherein the plurality of touch electrodes are used for touch position detection in a touch position detection period, and at least certain number of the plurality of touch electrodes are multiplexed as first pressure sensing electrodes in a touch force detection period; and

a second pressure sensing electrode disposed on a second substrate facing the first substrate and in a grid-shape, wherein orthogonal projection of the first pressure sensing electrodes on the second substrate is at least partially overlapped with the second pressure sensing electrode,

wherein, in the touch force detection period, the first pressure sensing electrodes and the second pressure sensing electrode are used together to detect a touch force applied on the display panel,

the second pressure sensing electrode includes grid lines and grid openings surrounded by the grid lines,

a sum S₁ of areas of the grid openings satisfies a first predetermined condition as;

S₁/S₀>

1−

K×

R₀/R_m,

wherein S₀ is an area of a plate electrode having a same contour as the second pressure sensing electrode, K is a shielding effect attenuation coefficient, R₀ is an impedance value of the plate electrode, and R_m is an impedance threshold.

15. A driving method for a display panel having a plurality of touch electrodes disposed on a first substrate and a second pressure sensing electrode disposed on a second substrate facing the first substrate and having grid lines and grid openings surrounded by the grid lines, wherein orthogonal projections, on the first substrate, of at least certain number of the grid openings in the second pressure sensing electrode overlap with corresponding first pressure sensing electrodes disposed on the first substrate, the driving method comprising:

in a touch position detection period, supplying the plurality of touch electrodes with a first drive signal, and receiving touch position detection signals through the plurality of touch electrodes; and

in a touch force detection period, multiplexing at least certain number of the plurality of touch electrodes as first pressure sensing electrodes, supplying the first pressure sensing electrodes with a second drive signal, supplying the second pressure sensing electrode with a fixed voltage, and receiving force detection signals through the first pressure sensing electrodes.

16. The driving method according to claim 15, further including:

in an image display period, multiplexing the plurality of touch electrodes as a common electrode, and supplying the plurality of touch electrodes with a common voltage signal.

17. The driving method according to claim 15, wherein:

in the touch position detection period, setting the second pressure sensing electrode to floating.