Touch panel having upper electrode plate including electrode, polarizing plate, quarter wave plate and heat-resistant transparent resin plate

• US 7,589,798 B2
• Filed: 09/05/2002
• Issued: 09/15/2009
• Est. Priority Date: 09/06/2001
• Status: Active Grant

• Current Assignee: Nissha Printing Company Limited
• Original Assignee: Nissha Printing Company Limited
• Inventors: Takahata, Kazuhiko, Nishikawa, Kazuhiro, Asakura, Takeshi, Hashimoto, Takao
• Primary Examiner(s): Nelms; David
• Assistant Examiner(s): Briggs; Nathanael R
• Application Number:
  US10/488,558
• Publication Number:
  US 20040239641A1
• Time in Patent Office: 2,567 Days
• Field of Search: 349/12, 345/173
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• 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
• CPC Class Codes: H01H 13/70 having a plurality of operating members associated with different sets of contacts, e.g. keyboard mounting together a plurality of independent switches H02B
• CPC Class Codes: H01H 13/703 characterised by spacers between contact carrying layers
• CPC Class Codes: H01H 2201/018 transparent
• CPC Class Codes: H01H 2209/06 transparent

Abstract

An upper electrode plate has a 0.15 to 0.8 mm thick optically isotropic heat-resistant transparent resin plate having a glass transition temperature characteristic of not less than 150° C. The heat-resistant transparent resin plate is laminated directly or indirectly on a quarter wave plate all over their surfaces.

Claims

1. A touch panel comprising:

an upper electrode plate including a lamination of

(i) an upper electrode formed as a transparent conductive film and defining a lower surface of said upper electrode plate,

(ii) a polarizing plate,

(iii) a quarter wave plate between said upper electrode and said polarizing plate, with an absorption axis of said polarizing plate crossing an optical axis of said quarter wave plate at an angle of 45°

or 135°

, and

(iv) a 0.15 to 0.80 mm thick optically isotropic heat-resistant transparent resin plate having a glass transition temperature of not less than 150°

C. and an absorption coefficient of not more than 1.3%, said heat-resistant transparent resin plate being laminated directly to, or indirectly to, said quarter wave plate, and being coextensive with said quarter wave plate; and

a lower electrode plate including a lower electrode formed as a transparent conductive film and defining an upper surface of said lower electrode plate,

wherein said upper electrode plate and said lower electrode plate are bonded and fixed to one another at regions except for a display area so that said upper electrode and said lower electrode oppose each other with via an air layer, and

wherein a seal layer covers side surfaces of said upper electrode plate and portions of said lower electrode plate that are adjacent said side surfaces such that said seal layer prevents penetration of water through said side surfaces of said upper electrode plate and said portions of said lower electrode plate into said touch panel and such that said side surfaces are not exposed.

2. The touch panel according to claim 1, wherein

said glass transition temperature of said heat-resistant transparent resin plate is not less than 170°

C.

3. The touch panel according to claim 1, wherein

said absorption coefficient of said heat-resistant transparent resin plate is not more than 1%.

4. The touch panel according to claim 1, wherein one of said polarizing plate and said heat-resistant transparent resin plate defines an upper surface of said upper electrode plate, and further comprising:

a moisture-proof PET film, as a satin layer, on said upper surface of said upper electrode plate, said moisture-proof PET film having low-reflection and antifouling functions.

5. The touch panel according to claim 1, wherein

said heat-resistant transparent resin plate is 0.20 to 0.70 mm thick.

6. The touch panel of claim 1, wherein said seal layer covers side-end peripheries of said polarizing plate, said quarter wave plate and said transparent resin plate.

7. A touch panel comprising:

an upper electrode plate including a lamination of

(i) an upper electrode formed as a transparent conductive film and defining a lower surface of said upper electrode plate,

(ii) a polarizing plate,

(iii) a quarter wave plate between said upper electrode and said polarizing plate, with an absorption axis of said polarizing plate crossing an optical axis of said quarter wave plate at an angle of 45°

or 135°

, and

(iv) a 0.15 to 0.80 mm thick optically isotropic heat-resistant transparent resin plate having a glass transition temperature of not less than 150°

C. and an absorption coefficient of not more than 1.3%, said heat-resistant transparent resin plate being laminated directly to, or indirectly to, said quarter wave plate, and being coextensive with said quarter wave plate; and

a lower electrode plate including a lower electrode formed as a transparent conductive film and defining an upper surface of said lower electrode plate,

wherein said upper electrode plate and said lower electrode plate are bonded and fixed to one another at regions except for a display area so that said upper electrode and said lower electrode oppose each other with via an air layer,

wherein said upper electrode plate has peripheral side surfaces that extend in a direction orthogonal to a plane of said lower surface of said upper electrode plate, and

wherein a seal layer covers and is positioned on said peripheral side surfaces of said upper electrode plate and portions of said lower electrode plate that are adjacent said peripheral side surfaces in a manner so as to prevent penetration of water into said touch panel through said peripheral side surfaces and said portions of said lower electrode plate that are adjacent said peripheral side surfaces.

8. The touch panel according to claim 7, wherein

said glass transition temperature of said heat-resistant transparent resin plate is not less than 170°

C.

9. The touch panel according to claim 7, wherein

said absorption coefficient of said heat-resistant transparent resin plate is not more than 1%.

10. The touch panel according to claim 7, wherein one of said polarizing plate and said heat-resistant transparent resin plate defines an upper surface of said upper electrode plate, and further comprising:

a moisture-proof PET film, as a satin layer, on said upper surface of said upper electrode plate, said moisture-proof PET film having low-reflection and antifouling functions.

11. The touch panel according to claim 7, wherein

said heat-resistant transparent resin plate is 0.20 to 0.70 mm thick.

12. The touch panel of claim 7, wherein said seal layer covers side-end peripheries of said polarizing plate, said quarter wave plate and said transparent resin plate.