Display device

• US 8,013,943 B2
• Filed: 09/28/2006
• Issued: 09/06/2011
• Est. Priority Date: 03/08/2006
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Kataoka, Yoshiharu, Tanaka, Shinya
• Primary Examiner(s): Healy; Brian
• Application Number:
  US12/093,489
• Publication Number:
  US 20090046077A1
• Time in Patent Office: 1,804 Days
• Field of Search: 349/12, 349/38, 349/39, 349/139, 349/142, 349/143, 345/173, 345/174
• US Class Current: 349/12
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0444 using a single conductive element covering the whole sensing surface, e.g. by sensing the electrical current flowing at the corners

Abstract

A display device includes: a first substrate and a second substrate disposed to face each other; a display medium layer interposed between the first substrate and the second substrate; a plurality of pixel electrodes arranged in a matrix between the first substrate and the display medium layer; a first transparent electrode, interposed between the second substrate and the display medium layer, for detecting a touched location; and a second transparent electrode, interposed between the first transparent electrode and the display medium layer, for receiving a display signal. The display device detects the touched location using a capacitive coupling method and displays an image. A shield electrode for suppressing capacitive coupling is formed between the first transparent electrode and the second transparent electrode.

Claims

1. A display device comprising:

a first substrate and a second substrate disposed to face each other;

a display medium layer interposed between the first substrate and the second substrate;

a plurality of pixel electrodes arranged in a matrix between the first substrate and the display medium layer;

a first transparent electrode, interposed between the second substrate and the display medium layer, for detecting a touched location; and

a second transparent electrode, interposed between the first transparent electrode and the display medium layer, for receiving a display signal,

wherein the display device detects the touched location using a capacitive coupling method and displays an image, and

a shield electrode for suppressing capacitive coupling between the first transparent electrode and the second transparent electrode is formed between the first transparent electrode and the second transparent electrode.

2. The display device of claim 1, wherein the shield electrode is configured so as to be grounded.

3. The display device of claim 1, wherein the shield electrode is formed of a transparent conductive film.

4. The display device of claim 3, wherein the transparent conductive film is formed of a compound of indium oxide and tin oxide, a compound of indium oxide and zinc oxide, or a compound of indium oxide and magnesium oxide.

5. The display device of claim 3, wherein the transparent conductive film is formed so as to have the same shape as, or a larger size than, the first transparent electrode.

6. The display device of claim 3, wherein the transparent conductive film is formed so as to have the same shape as, or a larger size than, the second transparent electrode.

7. The display device of claim 1, wherein the shield electrode is formed between the plurality of pixel electrodes.

8. The display device of claim 7, wherein the shield electrode is formed in a striped pattern.

9. The display device of claim 7, wherein the shield electrode is formed in a lattice.

10. The display device of claim 7, wherein the shield electrode is formed of a metal film impervious to light.

11. The display device of claim 10, wherein the metal film contains at least one metal element which is chromium, titanium, tungsten, molybdenum, tantalum or aluminum.

12. The display device of claim 1, wherein a first insulating layer is formed between the shield electrode and the first transparent electrode, and

a second insulating layer is formed between the shield electrode and the second transparent electrode.

13. The display device of claim 12, wherein the first insulating layer includes a color filter layer, and

the second insulating layer is an organic insulating layer.

14. The display device of claim 13, wherein the first insulating layer includes an organic insulating layer between the shield electrode and the color filter layer.

15. The display device of claim 13, wherein the first insulating layer includes an inorganic insulating layer between the first transparent electrode and the color filter layer.

16. The display device of claim 12, wherein the first insulating layer is an inorganic insulating layer, and

the second insulating layer is composed of a color filter layer formed close to the shield electrode and an organic insulating layer formed close to the second transparent electrode.

17. The display device of claim 12, wherein a color filter layer is formed between the second substrate and the first transparent electrode,

the first insulating layer is an inorganic insulating layer, and

the second insulating layer is an organic insulating layer.

18. The display device of claim 17, wherein an insulating layer is formed between the first transparent electrode and the color filter layer.

19. The display device of claim 1, wherein the first substrate and the second substrate are formed of transparent insulating material.