In-cell touch type display device

Patent metadata

Field	Value
Publication number	US-10664087-B2
Application number	US-201514985032-A
Country	US
Kind code	B2
Filing date	Dec 30, 2015
Priority date	Sep 8, 2015
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

The present disclosure provides an in-cell touch type display device including multiple first electrodes embedded in a display panel, at least one second electrode positioned outside the display panel, and a touch force sensing gap exiting between the multiple first electrodes and the second electrode such that a capacitor is formed between the multiple first electrodes and the second electrode.

First claim

What is claimed is:

1. An in-cell touch display device, comprising:
a plurality of first electrodes embedded in a display panel;
at least one second electrode outside the display panel and capacitively coupled to each of the first electrodes;
a gap structure unit configured to change a capacitance between the first electrodes and the at least one second electrode responsive to a touch force applied on a surface of the display panel, wherein the first electrodes are applied with a first electrode driving signal in a single touch driving period and the at least one second electrode is applied with a second electrode driving signal in the single touch driving period, a first turn-on voltage of the first electrode driving signal is lower than a second turn-on voltage of the second electrode driving signal, wherein the gap structure unit comprises:
a base plate on which the at least one second electrode is placed, and
a spacer elastic pattern on the at least one second electrode and supporting only edges of a lower structure to enable deforming of a non-edge portion of the lower structure between the edges responsive to the touch force, the spacer elastic pattern in conjunction with the at least one second electrode and the lower structure defining compressible air gap; and
a touch circuit coupled to the plurality of first electrodes and the at least one second electrode,
wherein all of the plurality of the first electrodes embedded in the display panel are configured to:
be applied with a common voltage as a display driving voltage configured to display an image on the display panel during a display driving period; and
be sequentially applied with the first electrode driving signal during the single touch driving period, and
wherein the touch circuit is configured to detect the touch force applied on the surface of the display panel and a coordinate of a touch, by processing a sensing signal representing a voltage level at each of the plurality of first electrodes during the single touch driving period.

2. The in-cell touch display device of claim 1 , wherein the capacitance between the plurality of first electrodes and the at least one second electrode is changed by a change in a distance between the plurality of first electrodes and the at least one second electrode.

3. The in-cell touch display device of claim 1 , wherein the lower structure is positioned beneath the display panel, the gap structure unit positioned beneath or inside the lower structure.

4. The in-cell touch display device of claim 3 , wherein the lower structure is a backlight unit.

5. The in-cell touch display device of claim 1 , wherein the at least one second electrode comprises a plurality of second electrodes, each of the second electrodes capacitively coupled to a subset of the first electrodes.

6. The in-cell touch display device of claim 1 , wherein the display driving period and the touch driving period is comprised in a frame period.

7. The in-cell touch display device of claim 1 , wherein the display panel comprises a substrate with a first polarization plate attached at a first side of the substrate facing a backlight unit and the plurality of first electrodes mounted on a second side opposite the first side.

8. The in-cell touch display device of claim 7 , wherein the backlight unit is under the first polarization plate.

9. The in-cell touch display device of claim 7 , wherein the display panel comprises a second polarization plate above the plurality of first electrodes.

10. The in-cell touch display device of claim 1 , wherein the spacer elastic pattern is attached, bonded or coated on a rear surface of the lower structure.

11. An in-cell touch display device, comprising:
a plurality of first electrodes embedded in a display panel;
at least one second electrode outside the display panel and capacitively coupled to each of the first electrodes;
a gap structure unit configured to change a capacitance between the plurality of first electrodes and the at least one second electrode responsive to a touch force applied on a surface of the display panel, wherein the first electrodes are applied with a first electrode driving signal in a single touch driving period and the at least one second electrode is applied with a second electrode driving signal in the single touch driving period, wherein the first electrode driving signal and the second electrode driving signal have different voltage levels wherein the gap structure unit comprises:
a base plate on which the at least one second electrode is placed, and
a spacer elastic pattern on the at least one second electrode and supporting only edges of a lower structure to enable deforming of a non-edge portion of the lower structure between the edges responsive to the touch force, the spacer elastic pattern in conjunction with the at least one second electrode and the lower structure defining compressible air gap; and
a touch circuit coupled to the plurality of first electrodes and the at least one second electrode,
wherein all of the plurality of the first electrodes embedded in the display panel are configured to:
be applied with a common voltage as a display driving voltage configured to display an image on the display panel during a display driving period; and
be sequentially applied with the first electrode driving signal during the single touch driving period, and
wherein the touch circuit is configured to detect the touch force applied on the surface of the display panel and a coordinate of a touch, by processing a sensing signal representing a voltage at each of the plurality of first electrodes.

Assignees

• Lg Display Co Ltd

Inventors

• Kim Cheolse
• Lee Buyeol
• Park Yongchan
• Ju Suyun

Classifications

• G06F3/044

  by capacitive means · CPC title

• G06F3/0414

  using force sensing means to determine a position · CPC title

• G06F3/0412 Primary

  Digitisers structurally integrated in a display · CPC title

• G06F3/0416 Primary

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/0445

  using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer · CPC title