Reflection resistant touch screens

• US 7,372,510 B2
• Filed: 02/28/2003
• Issued: 05/13/2008
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: Planar Systems Incorporated (Leyard Optoelectronic Co., Ltd.)
• Original Assignee: Planar Systems Incorporated (Leyard Optoelectronic Co., Ltd.)
• Inventors: Abileah, Adiel
• Primary Examiner(s): Ton; Toan
• Assistant Examiner(s): DUONG, TAI V
• Application Number:
  US10/376,155
• Publication Number:
  US 20030222857A1
• Time in Patent Office: 1,901 Days
• Field of Search: 349/12, 349/64, 349/96, 349/112, 349/117, 349/137, 349/173, 359/599, 359/485, 359/494, 359/497, 359/500, 359/501, 345/104, 345/173, 345174-176, 178/18.03, 178/18.05, 178/18.06, 178/18.07
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133528 Polarisers
• 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: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures

Abstract

A flexible, non-birefringent cover and a polarizer on the front of a resistive touch panel reduce touch screen image distortion and obscuration resulting from the reflection of ambient light. Reduced reflection of ambient light is also obtained by touch screens of alternative construction incorporating combinations anti-reflection panels and polarizers located behind the touch panel.

Claims

1. A touch screen comprising:

(a) a touch panel having a back surface and a front surface;

(b) a light valve including a polarizer comprising a birefringent carrier layer, said light valve arranged proximate to said touch panel and controlling an intensity of light transmitted through said touch panel;

(c) another polarizer interposed between said light valve and said touch panel; and

(d) an anti-reflection panel having a front surface and a back surface, said back surface arranged proximate to said front surface of said touch panel and said front surface comprising a glare diffusing surface.

2. The touch screen of claim 1 wherein said another polarizer comprises a birefringent film.

3. The touch screen of claim 1 wherein said birefringent carrier layer comprises polyester.

4. A touch screen comprising:

(a) a touch panel having a back surface and a front surface;

(b) a light valve including a polarizer, said light valve arranged proximate to said touch panel and controlling an intensity of light transmitted through said touch panel;

(c) another polarizer interposed between said light valve and said touch panel; and

(d) a first anti-reflection panel interposed between said light valve and said touch panel;

(e) a second anti-reflection panel interposed between said first anti-reflection panel and said touch panel

(f) a third anti-reflection panel having a back surface and a glare diffusing front surface, said back surface proximate to said front surface of said touch panel.

5. The touch screen of claim 4 wherein said first anti-reflection panel comprises a birefringent film having an anti-reflection coating.

6. The touch screen of claim 5 wherein said birefringent film comprises polyester.

7. The touch screen of claim 4 wherein said front surface of said touch panel comprises a glare diffusing surface.

8. The touch screen of claim 4 wherein said second anti-reflection panel comprises a birefringent film having an anti-reflection coating.

9. The touch screen of claim 4 wherein said birefringent film comprises polyester.

10. The touch screen of claim 4 wherein said front surface of said touch panel comprises a glare diffusing surface.

11. The touch screen of claim 4 further comprising a third anti-reflection panel proximate to said front surface of said touch panel.

12. The touch screen of claim 11 wherein said third anti-refection panel comprises a birefringent film having an anti-reflection coating.

13. The touch screen of claim 12 wherein said birefringent film comprises polyester.

14. The touch screen of claim 4 wherein said third anti-refection panel comprises a birefringent film having an anti-reflection coating.

15. The touch screen of claim 14 wherein said birefringent film comprises polyester.

16. A touch screen comprising:

(a) a touch panel having a back surface and a front surface;

(b) a light valve including a polarizer, said light valve arranged proximate to said touch panel and controlling an intensity of light transmitted through said touch panel;

(c) another polaraizer comprising a non-birefringent carrier layer interposed between said light valve and said touch panel; and

(d) a first anti-reflection panel interposed between said light valve and said touch panel;

(e) another anti-reflection panel having a front side and a back side proximate to said front surface of said touch panel;

(f) a front surface of said another anti-reflection panel comprises a glare diffusing surface.

17. The touch screen of claim 16 wherein said first anti-refection panel comprises a birefringent film having an anti-reflection coating.

18. The touch screen of claim 17 wherein said birefringent film comprises polyester.

19. The touch screen of claim 16 wherein said front surface of said touch panel comprises a glare diffusing surface.

20. The touch screen of claim 16 further comprising a second anti-reflection panel interposed between said first anti-reflection panel and said touch panel.

21. The touch screen of claim 20 wherein said second anti-refection panel comprises a birefringent film having an anti-reflection coating.

22. The touch screen of claim 21 wherein said birefringent film comprises polyester.

23. The touch screen of claim 20 wherein said front surface of said touch panel comprises a glare diffusing surface.

24. The touch screen of claim 16 wherein said another anti-refection panel comprises a birefringent film having an anti-reflection coating.

25. The touch screen of claim 24 wherein said birefringent film comprises polyester.

26. The touch screen of claim 16 wherein said another anti-refection panel comprises a birefringent film having an anti-reflection coating.

27. The touch screen of claim 26 wherein said birefringent film comprises polyester.

28. The touch screen of claim 16 wherein said another polarizer interposed between said light valve and said back surface of said touch panel is directly attached to said back surface of said touch panel.

29. The touch screen of claim 28 wherein said front surface of said touch panel comprises a glare diffusing surface.

30. The touch screen of claim 16 further comprising an air gap interposed between said light valve and said back surface of said touch panel.

31. The touch screen of claim 16 wherein said first anti-refection panel comprises a substantially non-birefringent film having an anti-reflection coating.

32. The touch screen of claim 31 wherein said substantially non-birefringent film comprises a polycarbonate.

33. The touch screen of claim 31 wherein said substantially non-birefringent film comprises triacetate cellulose.

34. The touch screen of claim 31 wherein said front surface of said touch panel comprises a glare diffusing surface.

35. The touch screen of claim 34 wherein said substantially non-birefringent film comprises a polycarbonate.

36. The touch screen of claim 34 wherein said substantially non-birefringent film comprises triacetate cellulose.

37. The touch screen of claim 36 further comprising a second anti-reflection panel interposed between said first anti-reflection panel and said touch panel.

38. The touch screen of claim 36 wherein said second anti-refection panel comprises a substantially non-birefringent film having an anti-reflection coating.

39. The touch screen of claim 38 wherein said substantially non-birefringent film comprises a polycarbonate.

40. The touch screen of claim 38 wherein said substantially non-birefringent film comprises triacetate cellulose.

41. The touch screen of claim 38 wherein said front surface of said touch panel comprises a glare diffusing surface.

42. The touch screen of claim 41 wherein said substantially non-birefringent film comprises a polycarbonate.

43. The touch screen of claim 41 wherein said substantially non-birefringent film comprises triacetate cellulose.

44. The touch screen of claim 37 further comprising further comprising a third anti-reflection panel having a front surface and a back surface, said back surface arranged proximate to said front surface of said touch panel.

45. The touch screen of claim 44 wherein said third anti-reflection panel comprises a birefringent film having an anti-reflection coating.

46. The touch screen of claim 45 wherein said birefringent film comprises polyester.

47. The touch screen of claim 44 wherein said front surface of said third anti-reflection panel comprises a glare diffusing surface.

48. The touch screen of claim 47 wherein said third anti-reflection panel comprises a birefringent film having an anti-reflection coating.

49. The touch screen of claim 48 wherein said birefringent film comprises polyester.

50. A touch screen comprising:

(a) a touch panel having a back surface and a front surface;

(b) a light valve including a polarizer, said light valve arranged proximate to said touch panel and controlling an intensity of light transmitted through said touch panel;

(c) another polaraizer comprising a non-birefringent carrier layer interposed between said light valve and said touch panel;

(d) a first anti-reflection panel interposed between said light valve and said touch panel;

(e) said first anti-refection panel comprises a substantially non-birefringent film having an anti-reflection coating;

(f) said front surface of said touch panel comprises a glare diffusing surface;

(g) said substantially non-birefringent film comprises triacetate cellulose;

(h) a second anti-reflection panel interposed between said first anti-reflection panel and said touch panel;

(i) a third anti-reflection panel having a front surface and a back surface, said back surface arranged proximate to said front surface of said touch panel;

(j) said front surface of said third anti-reflection panel comprises a glare diffusing surface.

51. The touch screen of claim 50 wherein said third anti-reflection panel comprises a birefringent film having an anti-reflection coating.

52. The touch screen of claim 51 wherein said birefringent film comprises polyester.