Integrated optical light sensitive active matrix liquid crystal display

• US 7,009,663 B2
• Filed: 12/17/2003
• Issued: 03/07/2006
• Est. Priority Date: 12/17/2003
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Planar Systems Incorporated (Leyard Optoelectronic Co., Ltd.)
• Inventors: Abileah, Adiel, den Boer, Willem, Tuenge, Richard T., Larsson, Terrance S.
• Primary Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US10/739,455
• Publication Number:
  US 20050134751A1
• Time in Patent Office: 811 Days
• Field of Search: 349/12, 349/24, 349/41, 349/42, 349/48, 349/95, 349/96, 349/110, 349/114, 345/87, 345/92, 345/102, 345/104, 345/175
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13312 Circuits comprising photodetectors for purposes other than feedback
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133565 inside the LC elements, i.e. between the cell substrates
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode

Abstract

A liquid crystal device including a front electrode layer, rear electrode layer, a liquid crystal material located between the front electrode layer and the rear electrode layer. A polarizer is located between the liquid crystal material and the front electrode layer and changing an electrical potential between the rear electrode layer and the front electrode layer modifies portions of the liquid crystal material to change the polarization of the light incident thereon. A plurality of light sensitive elements are located together with the rear electrode layer and a processor determines the position of at least one of the plurality of light sensitive elements that has been inhibited from sensing ambient light.

Claims

1. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) a polarizer located between said liquid crystal material and the front electrode layer;

(e) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(f) a plurality of light sensitive elements located together with said rear electrode layer; and

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light, whereby said processor distinguishes between ambient surrounding and said at least one of said plurality of light sensitive elements said inhibited from sensing said ambient light.

2. The device of claim 1 wherein it is free from a cover plate exterior to a supporting element for said front electrode layer.

3. The device of claim 1 wherein each of said light sensitive elements include a transistor.

4. The device of claim 3 wherein each of said light sensitive elements includes a first transistor that senses ambient light, and a second transistor that is inhibited from sensing ambient light with respect to said first transistor.

5. The device of claim 4 wherein at least one of said first transistor and said second transistor is a thin-film transistor.

6. The device of claim 5 wherein said thin-film transistor includes amorphous silicon.

7. The device of claim 4 wherein a terminal of said first transistor is connected to a terminal of said second transistor with a first conductor.

8. The device of claim 7 wherein said first conductor is capacitively coupled to a common line.

9. The device of claim 8 wherein said common line has a voltage potential less than said first conductor.

10. The device of claim 1 wherein said device is an active matrix liquid crystal device.

11. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(f) a plurality of light sensitive elements located within said display, wherein a plurality of said light sensitive elements are capable of sensing ambient light, wherein at least one other of said light sensitive elements is substantially inhibited from sensing ambient light;

(g) a processor that determines at least one of said plurality of light sensitive elements capable of said sensing ambient light that has been temporarily inhibited from sensing ambient light;

(h) said processor determines the position of the output of said at least one other of said light sensitive elements said substantially inhibited from sensing ambient light, and based upon said output modifying the sensing of other light sensitive elements, whereby said processor distinguishes between ambient surrounding and said at least one of said plurality of light sensitive elements said inhibited from sensing said ambient light.

12. The device of claim 11 wherein said light sensitive elements said substantially inhibited from sensing ambient light are transistors.

13. The device of claim 12 wherein said transistors are arranged in a row.

14. The device of claim 12 wherein said transistors are arranged in a column.

15. The device of claim 12 wherein said output of said at least one other of said light sensitive elements said substantially inhibited from sensing ambient light is a black current.

16. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a plurality of light sensitive elements located within said device;

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light, whereby said processor distinguishes between ambient surrounding and said at least one of said plurality of light sensitive elements said inhibited from sensing said ambient light; and

(h) a sensor that senses an impact with said device.

17. The device of claim 16 wherein said sensor is a pressure sensor.

18. The device of claim 16 wherein said sensor at least one of a vibration sensor and an accelerometer.

19. The device of claim 16 wherein said sensing from said sensor is used to determine that a user has touched said device.

20. The device of claim 16 wherein said sensing from said sensor is used to determine that a user has not touched said device.

21. The device of claim 16 wherein each of said light sensitive elements include a transistor.

22. The device of claim 21 wherein each of said light sensitive elements includes a first transistor that senses ambient light, and a second transistor that is inhibited from sensing ambient light with respect to said first transistor.

23. The device of claim 22 wherein at least one of said first transistor and said second transistor is a thin-film transistor.

24. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a plurality of light sensitive elements located within said device;

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light, whereby said processor distinguishes between ambient surrounding and said at least one of said plurality of light sensitive elements said inhibited from sensing said ambient light; and

(h) a lens located in front of at least one of said light sensitive elements to focus light impacting thereon on said at least one of said light sensitive elements.

25. The device of claim 24 further comprising a filter located between said light sensitive elements and the front of said display that inhibits ambient light from reaching said light sensitive elements.

26. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a plurality of light sensitive elements located within said device;

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light, whereby said processor distinguishes between ambient surrounding and said at least one of said plurality of light sensitive elements said inhibited from sensing said ambient light; and

(h) a filter located between said light sensitive elements and the front of said display that inhibits ambient light from reaching said light sensitive elements.

27. The device of claim 26 further comprising a lens located in front of at least one of said light sensitive elements to focus light impacting thereon on said at least one of said light sensitive elements.

28. The device of claim 27 wherein said filter is located in front of said liquid crystal material.

29. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) a polarizer located between said liquid crystal material and the front electrode layer;

(e) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(f) a plurality of light sensitive elements located together with said rear electrode layer; and

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light, whereby said processor senses at least three different levels as a result of one of said light sensitive elements said inhibited from sensing ambient light and provides at least three different output levels in response thereto.

30. The device of claim 29 wherein it is free from a cover plate exterior to a supporting element for said front electrode layer.

31. The device of claim 29 wherein each of said light sensitive elements include a transistor.

32. The device of claim 31 wherein each of said light sensitive elements includes a first transistor that senses ambient light, and a second transistor that is inhibited from sensing ambient light with respect to said first transistor.

33. The device of claim 32 wherein at least one of said first transistor and said second transistor is a thin-film transistor.

34. The device of claim 32 wherein a terminal of said first transistor is connected to a terminal of said second transistor with a first conductor.

35. The device of claim 34 wherein said first conductor is capacitively coupled to a common line.

36. The device of claim 35 wherein said common line has a voltage potential less than said first conductor.

37. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) a polarizer located between said liquid crystal material and the front electrode layer;

(e) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(f) a plurality of light sensitive elements located together with said rear electrode layer wherein said light sensitive elements include a transistor that includes a first terminal interconnected to a first terminal of a capacitor and a second terminal interconnected to a second terminal of said transistor and a third terminal comprising a gate interconnected to a bias point in common with other gates of other said transistors; and

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light.

38. The device of claim 37 wherein it is free from a cover plate exterior to a supporting element for said front electrode layer.

39. The device of claim 37 wherein each of said light sensitive elements includes a first transistor that senses ambient light, and a second transistor that is inhibited from sensing ambient light with respect to said first transistor.

40. The device of claim 39 wherein a terminal of said first transistor is connected to a terminal of said second transistor with a first conductor.

41. The device of claim 40 wherein said first conductor is capacitively coupled to a common line.

42. The device of claim 41 wherein said common line has a voltage potential less than said first conductor.

43. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a plurality of light sensitive elements located within said device;

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light;

(h) a sensor that senses an impact with said device; and

(i) said processor correlating said impact from said sensor with said position to confirm that at least one of said plurality of light sensitive elements has been said inhibited from sensing ambient light.

44. The device of claim 43 wherein said sensor is a pressure sensor.

45. The device of claim 43 wherein said sensor at least one of a vibration sensor and an accelerometer.

46. The device of claim 43 wherein said sensing from said sensor is used to determine that a user has touched said device.

47. The device of claim 43 wherein said sensing from said sensor is used to determine that a user has not touched said device.

48. A liquid crystal device comprising:

(a) a front electrode layer;

(b) a rear electrode layer;

(c) a liquid crystal material located between said front electrode layer and said rear electrode layer;

(d) changing an electrical potential between said rear electrode layer and said front electrode layer to selectively modify portions of said liquid crystal material to change the polarization of the light incident thereon;

(e) a plurality of light sensitive elements located within said device;

(g) a processor that determines the position of at least one of said plurality of light sensitive elements that has been inhibited from sensing ambient light; and

(h) a transmissive filter that passes a first color while inhibiting the passage of a second color that is located between said light sensitive elements and the front of said display that inhibits ambient light of said second color from reaching said light sensitive elements.

49. The device of claim 48 further comprising a lens located in front of at least one of said light sensitive elements to focus light impacting thereon on said at least one of said light sensitive elements.

50. The device of claim 48 wherein said filter is located in front of said liquid crystal material.