TOUCH PANEL

• US 20090188726A1
• Filed: 04/25/2008
• Published: 07/30/2009
• Est. Priority Date: 01/28/2008
• Status: Active Grant

• Current Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Delta Electronics Incorporated
• Inventors: Chang, Sean, Chen, Yang-Lin
• Granted Patent: US 8,305,350 B2
• Time in Patent Office: Days
• US Class Current: 178/18.30
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A touch panel includes two transparent conductive films and at least one refractive index matching layer. The two transparent conductive films are disposed opposite to each other. The refractive index matching layer is disposed between the two transparent conductive films or disposed on one side of the transparent conductive film.

Claims

1. A touch panel comprising:

two transparent conductive films disposed opposite to each other; and

at least one first refractive index matching layer disposed between the transparent conductive films or disposed on one side of the transparent conductive film.

2. The touch panel according to claim 1, wherein a material of the transparent conductive film comprises indium tin oxide (ITO), indium zinc oxide, aluminum zinc oxide, gallium zinc oxide, zinc oxide, tin oxide or a combination thereof.

3. The touch panel according to claim 1, wherein the first refractive index matching layer has a refractive index smaller than that of the transparent conductive films.

4. The touch panel according to claim 1, wherein the first refractive index matching layer has a refractive index ranging from 1 to 2.

5. The touch panel according to claim 1, wherein the first refractive index matching layer comprises materials with different refractive indices.

6. The touch panel according to claim 1, further comprising at least one spacer disposed inside the first refractive index matching layer to separate the two transparent conductive films.

7. The touch panel according to claim 6, wherein the first refractive index matching layer is an elastic insulating layer or a liquid refractive index matching layer.

8. The touch panel according to claim 6, wherein a material of the first refractive index matching layer comprises silicone, epoxy or a combination thereof.

9. The touch panel according to claim 1, further comprising at least one spacer disposed between the two first refractive index matching layers to separate the two first refractive index matching layers.

10. The touch panel according to claim 9, wherein the first refractive index matching layer has an electroconductive property.

11. The touch panel according to claim 9, wherein a material of the first refractive index matching layer comprises a transparent conductive material, indium tin oxide (ITO), indium zinc oxide, aluminum zinc oxide, gallium zinc oxide, zinc oxide, tin oxide or combinations thereof.

12. The touch panel according to claim 11, wherein a material of the first refractive index matching layer further comprises a transparent dielectric material, silicon dioxide, cryolite or magnesium fluoride.

13. The touch panel according to claim 1, wherein the first refractive index matching layer is a single layer or a composite layer composed of alternately stacked high and low refractive index layers.

14. The touch panel according to claim 13, wherein a portion of materials of the first refractive index matching layer has a refractive index greater than that of the transparent conductive film.

15. The touch panel according to claim 1, further comprising two transparent substrates respectively disposed on sides of the transparent conductive films.

16. The touch panel according to claim 15, wherein each of the transparent substrates is a glass substrate, a plastic substrate, polyethelyne (PE), polycarbonate (PC) or polyethylene terephthalate (PET).

17. The touch panel according to claim 15, further comprising at least one spacer disposed between the two transparent conductive films to separate the two transparent conductive films, wherein the two first refractive index matching layers are respectively disposed between the transparent substrates and the transparent conductive films.

18. The touch panel according to claim 17, wherein a material of the first refractive index matching layer comprises niobium oxide, titanium oxide, tantalum oxide, zirconium oxide, silicon oxide, magnesium oxide or combinations thereof.

19. The touch panel according to claim 17, wherein a refractive index of the first refractive index matching layer ranges from a refractive index of the transparent conductive film to that of the transparent substrate.

20. The touch panel according to claim 17, wherein each of the first refractive index matching layers and one of the transparent conductive films are coated on one of the transparent substrates in one batch.

21. The touch panel according to claim 17, wherein one of the transparent substrates has a hardened layer formed thereon.

22. The touch panel according to claim 9, further comprising a second refractive index matching layer or an air layer disposed between the two first refractive index matching layers.

23. The touch panel according to claim 22, wherein the second refractive index matching layer is an elastic insulating layer or a liquid refractive index matching layer, and a material of the elastic insulating layer comprises silicone, epoxy or combinations thereof, and a refractive index of the second refractive index matching layer ranges from 1.3 to 1.7.

24. The touch panel according to claim 17, further comprising a second refractive index matching layer or an air layer disposed between the two transparent conductive films.

25. The touch panel according to claim 24, wherein the second refractive index matching layer is an elastic insulating layer or a liquid refractive index matching layer, and a material of the elastic insulating layer comprises silicone, epoxy or combinations thereof, and a refractive index of the second refractive index matching layer ranges from 1.3 to 1.7.