Transparent Planar Body and Transparent Touch Switch

• US 20080138589A1
• Filed: 05/24/2006
• Published: 06/12/2008
• Est. Priority Date: 05/26/2005
• Status: Active Grant

• Current Assignee: Gunze Limited
• Original Assignee: Gunze Limited
• Inventors: Yamada, Tsutomu, Tsukamoto, Keiji, Wakabayashi, Naohiro, Sasaki, Kuniaki, Furukawa, Shuji
• Granted Patent: US 8,603,611 B2
• Time in Patent Office: Days
• US Class Current: 428/195.1
• 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 3/044 by capacitive means
• 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
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: H01H 13/83 characterised by legends, e.g. Braille, liquid crystal displays, light emitting or optical elements
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

The present invention provides a transparent planar body and a transparent touch switch that can improve visibility. Specifically, the transparent planar body (1) has a patterned transparent conductive film (12) on at least one surface of a transparent substrate (11). This transparent planar body (1) comprises a transmittance-adjusting layer for equalizing the transmission spectrum of light transmitted through a patterned region wherein the transparent conductive film (12) is provided via the transparent substrate (11) with that transmitted through a non-patterned region wherein the transparent conductive film (12) is not provided via the transparent substrate (11).

Claims

1. A transparent planar body comprising:

a transparent substrate;

a patterned transparent conductive film provided on at least one surface of the transparent substrate; and

a transmittance-adjusting layer for equalizing the transmission spectrum of light that is transmitted through a patterned region where the transparent conductive film is provided via the transparent substrate with that transmitted through a non-patterned region where the transparent conductive film is not provided.

2. A transparent planar body according to claim 1, wherein the transmittance-adjusting layer comprises an overcoat layer covering one surface of the transparent substrate with a substantially uniform thickness, where the overcoat layer is thicker and has a lower refractive index than the transparent conductive film.

3. A transparent planar body according to claim 2, wherein the overcoat layer is formed of a silicon-tin oxide.

4. A transparent planar body according to claim 3, wherein the overcoat layer has a thickness of 70 to 80 nm.

5. A transparent planar body according to any one of claims 2 to 4, wherein the difference in the refractive index between the transparent conductive film and the overcoat layer falls within the range of 0.03 to 0.4.

6. A transparent planar body according to claim 2, wherein an undercoat layer lies between the transparent substrate and the transparent conductive film,

the undercoat layer has a laminated structure comprising at least two layers having different light refractive indices, and

the transparent conductive film is formed on the low refractive index layer side.

7. A transparent touch switch comprising a plurality of transparent planar bodies of claim 2,

the transparent planar bodies being attached to each other via an adhesive layer and functioning as a transparent electrostatic capacitive touch switch, and

the adhesive layer having a lower refractive index than the transparent conductive film.

8. A transparent touch switch according to claim 7, which further comprises a linear polarizing plate on the front side.

9. A transparent touch switch according to claim 7, which further comprises a linear polarizing plate and a quarter-wave plate on the front side and a quarter-wave plate on the back side.

10. A transparent touch switch according to claim 8, wherein the transparent substrate is a quarter-wave plate.

11. A transparent planar body according to claim 1, wherein the transmittance-adjusting layer is provided with an undercoat layer formed from a laminate comprising a low refractive index layer, and a high refractive index layer whose light refractive index is higher than that of the low refractive index layer,

the undercoat layer lies between the transparent substrate and the transparent conductive film in such a manner that the transparent conductive film is disposed on the low refractive index layer side, and

the high refractive index layer is thinner than the low refractive index layer.

12. A transparent planar body according to claim 11, wherein the thickness of the high refractive index layer falls within the range of 10 to 25 nm and that of the low refractive index layer falls within the range of 25 to 45 nm.

13. A transparent planar body according to claim 12, wherein the high refractive index layer is formed of a silicon-tin oxide and the low refractive index layers formed of a silicon oxide.

14. A transparent planar body according to any one of claims 11 to 13, wherein the thickness of the transparent conductive film falls within the range of 10 to 25 nm.

15. A transparent electrostatic capacitive touch switch comprising a plurality of transparent planar bodies of claim 11,

the plurality of transparent planar bodies being attached to each other via an adhesive layer.

16. A transparent electrostatic capacitive touch switch comprising a plurality of transparent planar bodies according to claim 11,

the plurality of transparent planar bodies being attached to each other via an adhesive layer in such a manner that the transparent conductive films face each other,

the thickness of the transparent conductive film being 20 to 25 nm, and

the refractive index of the adhesive layer being not less than 1.6.

17. A transparent electrostatic capacitive touch switch comprising a plurality of transparent planar bodies according to claim 11,

the plurality of transparent planar bodies being attached to each other via an adhesive layer in such a manner that the transparent conductive films face each other,

the thickness of the transparent conductive film being 25 to 30 nm, and

the refractive index of the adhesive layer being not less than 1.7.

18. A transparent touch switch according to any one of claims 15 to 17, which further comprises a linear polarizing plate on the front side.

19. A transparent touch switch according to any one of claims 15 to 17, which further comprises a linear polarizing plate and a quarter-wave plate on the front side and a quarter-wave plate on the back side.

20. A transparent touch switch according to claim 18, wherein the transparent substrate is a quarter-wave plate.

21. A transparent planar body according to claim 1, wherein the transmittance-adjusting layer comprises a cover layer for covering an exposed portion on one surface of the transparent substrate where the transparent conductive film is not provided,

the cover layer is formed so that the surface thereof is flush with that of the transparent conductive film, and

the refractive index of the cover layer is equivalent to that of the transparent conductive film.

22. A transparent planar body according to claim 21, wherein the cover layer is formed of a silicon-tin oxide.

23. A transparent planar body according to claim 21 or 22, wherein the transparent conductive film is formed of a carbon nanotube composite material.

24. A transparent planar body according to claim 21, which further comprises an undercoat layer that is formed of a laminate of a low refractive index layer and a high refractive index layer, the high refractive index layer having a light refractive index higher than the low refractive index layer,

in the transparent planar body, the undercoat layer lies between the transparent conductive film and the cover layer and the transparent substrate so that the transparent conductive film and the cover layer are disposed on the low refractive index layer side.

25. A transparent planar body according to claim 21, which further comprises an overcoat layer covering the surfaces of the transparent conductive film and the cover layer, wherein the surface of the overcoat layer is flat.

26. A transparent electrostatic capacitive touch switch comprising a plurality of transparent planar bodies of claim 21,

the plurality of transparent planar bodies being attached to each other via an adhesive layer.

27. A transparent resistive film-type touch switch comprising a plurality of transparent planar bodies of claim 21,

the plurality of transparent planar bodies being arranged so as to have a predetermined space therebetween produced by a spacer in such a manner that the transparent conductive films face each other.

28. A transparent touch switch according to claim 26 or 27, which comprises a linear polarizing plate on the front side.

29. A transparent touch switch according to claim 26 or 27, which comprises a linear polarizing plate and a quarter-wave plate on the front side and a quarter-wave plate on the back side.

30. A transparent touch switch according to claim 28, wherein the transparent substrate is a quarter-wave plate.

31. A transparent planar body according to claim 1, wherein the transparent conductive film comprises a plurality of belt-like transparent conductive members disposed with a predetermined space therebetween,

the transmittance-adjusting layer comprises a belt-like transparent controlling member disposed between two adjacent belt-like transparent conductive members via an insulating slit, and

the belt-like transparent controlling member is formed of the same material as that of the belt-like transparent conductive member and comprises a plurality of resistive slits.

32. A transparent planar body according to claim 31, wherein the plurality of resistive slits are arranged so as to connect one insulating slit to another each disposed adjacent to each belt-like transparent controlling member.

33. A transparent planar body according to claim 31 or 32, which further comprises a separating slit along the insulating slit so as to separate each belt-like transparent controlling member.

34. A transparent electrostatic capacitive touch switch comprising a plurality of transparent planar bodies of claim 31,

the plurality of transparent planar bodies being attached to each other via an adhesive layer.

35. A transparent resistive film-type touch switch comprising a plurality of transparent planar bodies of claim 31,

the plurality of transparent planar bodies being arranged so as to have a predetermined space therebetween produced by a spacer and that the belt-like transparent electric conductors face each other.

36. A transparent touch switch according to claim 34 or 35, which comprises a linear polarizing plate on the front side.

37. A transparent touch switch according to claim 34 or 35, which comprises a linear polarizing plate and a quarter-wave plate on the front side and a quarter-wave plate on the back side.

38. A transparent touch switch according to claim 36, wherein the transparent substrate is a quarter-wave plate.