Touch screen with polarizer and method of making same

• US 6,395,863 B2
• Filed: 02/02/2001
• Issued: 05/28/2002
• Est. Priority Date: 02/02/2000
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: MicroTouch Systems, Inc. (3M Company)
• Inventors: Geaghan, Bernard O.
• Primary Examiner(s): Boykin, Terressa M.
• Application Number:
  US09/776,289
• Publication Number:
  US 20010046604A1
• Time in Patent Office: 480 Days
• Field of Search: 428/412 528/176,193,194,196
• US Class Current: 528/196
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133528 Polarisers
• 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: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/31786 Of polyester [e.g., alkyd, etc.]

Abstract

A topsheet for a touch screen includes a support layer having a touch surface and a second surface opposite the touch surface; a polarizer layer having a first surface and a second surface with the first surface of the polarizer in contact with the second surface of said support layer; and a first conductive layer in contact with the second surface of said polarizer.

Claims

1. A topsheet for a touch screen comprising

a support layer having a touch surface and a second surface opposite the touch surface;

a polarizer layer having a first surface and a second surface with the first surface in contact with the second surface of said support layer; and

a first conductive layer in contact with the second surface of said polarizer.

2. The topsheet structure of claim 1 wherein the support layer is a polyester sheet.

3. The topsheet structure of claim 1 wherein the support layer is a polycarbonate sheet.

4. The topsheet structure of claim 1 wherein the polarizer layer includes a K type polarizer.

5. The topsheet structure of claim 1 including a first hardcoat layer in contact with the second surface of said polarizer layer and said first conductive layer is in contact with said first hardcoat layer.

6. The topsheet structure of claim 5 wherein said first hardcoat layer has a roughened finish.

7. The topsheet structure of claim 5 including an adhesion promoting agent in contact with the second surface of said polarizer layer.

8. The topsheet structure of claim 1 including a second hardcoat layer in contact with the touch surface of said support layer.

9. The topsheet structure of claim 1 wherein said first conductive layer includes a plurality of discrete sections of a conductive material.

10. The topsheet structure of claim 1 wherein the touch screen is a resistive film type touch screen and said first conductive layer engages a second conductive layer of the touch screen.

11. A method of manufacturing a topsheet for a touch screen comprising

providing a support layer having a touch surface and a second surface opposite the touch surface;

laminating a polarizer layer to the touch surface of said support layer, said polarizer layer having a top surface and a bottom surface; and

coating the bottom surface of said polarizer layer with at least a conductive layer.

12. The method of manufacturing a topsheet of claim 11 further comprising applying a first hardcoat layer to the bottom surface of said polarizer layer prior to said coating step.

13. The method of manufacturing a topsheet of claim 12 further comprising applying an adhesion promoting agent to the bottom surface of said polarizer prior to the step of applying said first hardcoat layer.

14. The method of manufacturing a topsheet of claim 12 wherein said hardcoat layer includes a rough surface.

15. The method of manufacturing a topsheet of claim 11 further comprising coating the touch surface of said support layer with a second hardcoat layer.

16. The method of manufacturing a topsheet of claim 12 wherein said coating step is a vacuum sputtering process.

17. The method of manufacturing a topsheet of claim 16 further comprising plasma etching said first hardcoat layer prior to said vacuum sputtering process.

18. The method of manufacturing a topsheet of claim 11 further comprising applying at least one thin film metal oxide layer to the bottom surface of said polarizer layer prior to said coating step.

19. The method of manufacturing a topsheet of claim 12 further comprising applying at least one thin film metal oxide layer to said first hardcoat layer prior to the coating step.

20. The method of manufacturing a topsheet of claim 11 wherein said coating step is a vacuum sputtering process.

21. The method of manufacturing a topsheet of claim 20 further comprising plasma etching said polarizer layer prior to said coating step.

22. A touch panel, comprising:

a touch sheet formed from a support layer, a polarizer layer, and a first conductive layer laminated together, the polarizer layer being disposed between the support layer and the first conductive layer, the support layer being disposed on a viewing side of the touch sheet.

23. A touch panel as recited in claim 22, further comprising a second conductive layer spaced apart from the first conductive layer of the touch sheet.

24. A touch panel as recited in claim 23, wherein the touch sheet is adapted to resiliently flex towards the second conductive layer under an applied pressure on the viewing side of the touch sheet.

25. A touch panel as recited in claim 23, further comprising spacer dots disposed between the first and second conductive layers.

26. A touch panel as recited in claim 23, further comprising a substrate layer, the second conductive layer being disposed on the substrate layer, between the substrate layer and the touch sheet.

27. A touch panel as recited in claim 22, further comprising a first hardcoat layer disposed on a touch surface of the support layer.

28. A touch panel as recited in claim 22, further comprising a second hardcoat layer disposed between the first polarizer layer and the first conductive layer.

29. A touch panel as recited in claim 28, wherein the second hardcoat layer has a roughened finish.

30. A touch panel as recited in claim 28, further comprising an adhesive promoter disposed between the first polarizer layer and the second hardcoat layer.

31. A touch panel as recited in claim 22, further comprising an antireflection layer disposed between the first polarizer layer and the first conductive layer.

32. A touch panel as recited in claim 22, wherein the support layer is a polyester sheet.

33. A touch panel as recited in claim 22, wherein the support layer is a polycarbonate sheet.

34. A touch panel as recited in claim 22, wherein the polarizer layer includes a K type polarizer.

35. A touch panel as recited in claim 22, wherein the first conductive layer includes a plurality of discrete sections of a conductive material.

36. A display system, comprising:

a display unit for displaying information to a viewer position; and

a touch unit disposed between the display unit and the viewer position, the touch unit including a touch sheet formed from a support layer, a first polarizer layer, and a first conductive layer laminated together, the first polarizer layer being disposed between the support layer and the first conductive layer, the support layer being disposed toward the viewer position.

37. A display system as recited in claim 36, wherein the display unit is a liquid crystal display (LCD) unit.

38. A display system as recited in claim 37, wherein the LCD unit includes first and second substantially parallel substrate layers, a liquid crystal layer is disposed between a first side of the first substrate layer and a first side of the second substrate layer, and the touch unit is disposed between the first substrate layer and the viewer position.

39. A display system as recited in claim 38, further comprising a second polarizer layer disposed to a second side of the second substrate layer opposite the first side of the second substrate layer.

40. A display system as recited in claim 37, wherein the touch unit further includes a second conductive layer spaced apart from the first conductive layer.

41. A display system as recited in claim 40, wherein the second conductive layer is disposed over a second side of the first substrate layer opposite the first side of the first substrate layer.

42. A display system as recited in claim 40, further comprising spacer dots separating the first conductive layer from the second conductive layer.

43. A display system as recited in claim 40, wherein the touch unit further includes a touch substrate layer disposed between the touch sheet and the display unit, the second conductive layer disposed on the touch substrate layer, between the touch substrate layer and the touch sheet.

44. A display system as recited in claim 36, wherein the touch unit further includes a second conductive layer spaced apart from the first conductive layer.

45. A display system as recited in claim 44, wherein the touch unit includes a touch substrate disposed between the touch sheet and the display unit, and the second conductive layer is laminated with the touch substrate.

46. A display system as recited in claim 44, wherein the second conductive layer is disposed on the display unit.