Structure for integrated touch screen

• US 10,133,382 B2
• Filed: 10/02/2014
• Issued: 11/20/2018
• Est. Priority Date: 05/16/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Yang, Byung Duk, Kim, Kyung Wook, Lee, Szu-Hsien, Chang, Shih-Chang, Zhong, John Z.
• Primary Examiner(s): Lee, Jr., Kenneth B
• Application Number:
  US15/311,836
• Publication Number:
  US 20170168619A1
• Time in Patent Office: 1,510 Days
• Field of Search: None
• CPC Class Codes: G02F 1/133302 Rigid substrates, e.g. inorganic substrates
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

A touch screen is disclosed. The touch screen can comprise a substrate having a first surface upon which a touch or proximity event is to be detected, and a second surface that opposes the first surface, and a touch sensor electrode and a first display pixel including a first display pixel TFT formed on the second surface of the substrate. The first touch sensor electrode can be disposed between the second surface of the substrate and the first display pixel TFT, and the first touch sensor electrode can be configured to detect the touch or proximity event. In some examples, the substrate can comprise a TFT glass substrate. In some examples, the touch screen can comprise a first touch sensor routing electrically coupled to the first touch sensor electrode, wherein the first touch sensor routing is disposed between the second surface of the substrate and the first display pixel TFT.

Claims

1. A touch screen comprising:

a substrate having a first surface upon which a touch or proximity event is to be detected, and a second surface that opposes the first surface; and

a first touch sensor electrode and a first display pixel including a first display pixel TFT and a liquid crystal material formed on the second surface of the substrate, wherein;

the first touch sensor electrode is disposed between the second surface of the substrate and the first display pixel TFT,

the first display pixel TFT is disposed between the first touch sensor electrode and the liquid crystal material, and

the first touch sensor electrode is configured to detect the touch or proximity event.

2. The touch screen of claim 1, wherein the substrate comprises a TFT glass substrate.

3. The touch screen of claim 1, further comprising:

a first touch sensor routing electrically coupled to the first touch sensor electrode and configured to transmit one or more touch signals associated with the first touch sensor electrode to sense circuitry, wherein the first touch sensor routing is disposed in a layer between the second surface of the substrate and the first display pixel TFT.

4. The touch screen of claim 3, wherein the first touch sensor routing is disposed in a layer between the first touch sensor electrode and the first display pixel TFT.

5. The touch screen of claim 3, further comprising:

a second touch sensor routing electrically coupled to a second touch sensor electrode, the second touch sensor routing disposed in a layer between the second surface of the substrate and the first display pixel TFT,

wherein the first touch sensor electrode includes a gap at a location corresponding to a location of the second touch sensor routing in the touch screen.

6. The touch screen of claim 3, further comprising a black mask disposed between the first touch sensor routing and the second surface of the substrate, the black mask configured to hide the first touch sensor routing on the touch screen.

7. The touch screen of claim 1, further comprising a second display pixel including a second display pixel TFT formed on the second surface of the substrate,

wherein the first touch sensor electrode is disposed in a layer between the second surface of the substrate and the second display pixel TFT.

8. The touch screen of claim 7, further comprising:

a common electrode associated with the first display pixel and the second display pixel, the common electrode configured to control a first luminance of the first display pixel and a second luminance of the second display pixel,

wherein the first touch sensor electrode is disposed in a layer between the second surface of the substrate and the common electrode.

9. The touch screen of claim 1, wherein the first touch sensor electrode comprises part of a pixelated self-capacitance touch sensor electrode pattern.

24. The touch screen of claim 1, further comprising:

a common electrode associated with the first display pixel and configured to control a luminance of the first display pixel; and

a pixel electrode associated with the first display pixel and configured to control the luminance of the first display pixel,

wherein the first touch sensor electrode is disposed in a layer between the common electrode and the second surface of the substrate, and between the pixel electrode and the second surface of the substrate.

25. The touch screen of claim 24, wherein the common electrode and the pixel electrode are disposed in one or more layers between the first display pixel TFT and a color filter associated with the first display pixel.

10. A touch screen comprising:

a substrate having a first surface upon which a touch or proximity event is to be detected, and a second surface that opposes the first surface; and

a touch sensor electrode layer, a display pixel TFT layer, and a liquid crystal material formed on the second surface of the substrate, wherein;

the touch sensor electrode layer is disposed between the second surface of the substrate and the display pixel TFT layer,

the display pixel TFT layer is disposed between the touch sensor electrode layer and the liquid crystal material, and

the touch sensor electrode layer has a plurality of touch sensor electrodes configured to detect the touch or proximity event.

11. The touch screen of claim 10, wherein the substrate comprises a TFT glass substrate.

12. The touch screen of claim 10, further comprising a touch sensor routing layer disposed between the second surface of the substrate and the display pixel TFT layer,

wherein the touch sensor routing layer includes touch sensor routing electrically coupled to the plurality of touch sensor electrodes, and is configured to transmit one or more touch signals associated with the touch sensor electrodes.

13. The touch screen of claim 12, wherein the touch sensor routing layer is disposed between the touch sensor electrode layer and the display pixel TFT layer.

14. The touch screen of claim 12, wherein one or more of the touch sensor electrodes include one or more gaps at locations corresponding to the touch sensor routing.

15. The touch screen of claim 10, further comprising:

a common electrode layer configured to control luminances of a plurality of display pixels; and

a pixel electrode layer configured to control the luminances of the plurality of display pixels,

wherein the touch sensor electrode layer is disposed between the common electrode layer and the second surface of the substrate, and between the pixel electrode layer and the second surface of the substrate.

16. The touch screen of claim 15, wherein the common electrode layer and the pixel electrode layer are disposed between the display pixel TFT layer and a color filter layer.

17. The touch screen of claim 10, wherein the plurality of touch sensor electrodes comprise part of a self-capacitance touch sensor electrode pattern.

18. A method for fabricating a touch screen, the method comprising:

forming a first touch sensor electrode on a second surface of a substrate, the substrate having the second surface and a first surface that opposes the second surface, the first surface being a surface upon which a touch or proximity event is to be detected by the first touch sensor electrode; and

forming a first display pixel including a first display pixel TFT and a liquid crystal material on the second surface of the substrate,

wherein the first touch sensor electrode is disposed between the second surface of the substrate and the first display pixel TFT, and the first display pixel TFT is disposed between the first touch sensor electrode and the liquid crystal material.

19. The method of claim 18, wherein the substrate comprises a TFT glass substrate.

20. The method of claim 18, further comprising:

forming a first touch sensor routing electrically coupled to the first touch sensor electrode and configured to transmit one or more touch signals associated with the first touch sensor electrode to sense circuitry, wherein the first touch sensor routing is formed in a layer between the second surface of the substrate and the first display pixel TFT.

21. The method of claim 20, further comprising:

forming a second touch sensor electrode on the second surface of the substrate; and

forming a second touch sensor routing electrically coupled to the second touch sensor electrode,

wherein the forming the first touch sensor electrode comprises forming the first touch sensor electrode with a gap at a location corresponding to a location of the second touch sensor routing in the touch screen.

22. The method of claim 20, further comprising:

forming a common electrode associated with the first display pixel and configured to control a luminance of the first display pixel; and

forming a pixel electrode associated with the first display pixel and configured to control the luminance of the first display pixel,

wherein the first touch sensor electrode is formed in a layer between the common electrode and the second surface of the substrate, and between the pixel electrode and the second surface of the substrate.

23. The method of claim 18, wherein the first touch sensor electrode comprises part of a pixelated self-capacitance touch sensor electrode pattern.