Displaying device and displaying method and manufacturing method of the device

• US 6,816,140 B2
• Filed: 12/07/2001
• Issued: 11/09/2004
• Est. Priority Date: 12/12/2000
• Status: Expired due to Term

• Current Assignee: Vista Peak Ventures LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: NEC Corporation
• Inventors: Fujieda, Ichiro
• Primary Examiner(s): Vu, David
• Application Number:
  US10/013,263
• Publication Number:
  US 20020140879A1
• Time in Patent Office: 1,068 Days
• Field of Search: 315/169.1, 315/169.3, 345/205, 345/206, 345/76, 345/92
• US Class Current: 345/87
• CPC Class Codes: G02F 1/011 in optical waveguides, not otherwise provided for in this subclass
• CPC Class Codes: G02F 1/1326 Liquid crystal optical waveguides or liquid crystal cells specially adapted for gating or modulating between optical waveguides

Abstract

A displaying device, which can reduce the power consumption, compared with a conventional displaying device in which the reduction of the power consumption is difficult because light is extracted from each of light emitting elements in time series, and also can prevent a displayed image from deteriorating caused by light entering from the outside or a light loss in a waveguide array, is provided. In the displaying device, a light emitting array controls each of light emitting elements. A waveguide array is formed by patterning a photosensitive resin formed on a supporting substrate having a light absorbing layer. A light extracting section extracts light at the same time form a predetermined selected region of the plural light emitting elements. The light extracting section also provides an antireflection layer on the surface facing to an observer. The extracting efficiency at the light extracting section is corrected corresponding to a light loss in the waveguide array. The light extracting section uses an optical material whose refractive index is changed by an external electric field.

Claims

1. A displaying device, comprising:

a light emitting means that emits light of one line of a displaying image by plural light emitting elements,

a waveguide array that propagates light inputted from said light emitting means from one end to the other end of a displaying region; and

a light extracting means that extracts light propagating in said waveguide array from an arbitrarily selected region;

wherein the light which is propagated through a waveguide array is extracted by said light extracting means to illuminate a display.

2. A displaying device in accordance with claim 1, wherein:

said arbitrarily selected region includes at least two or more pixels.

3. A displaying device in accordance with claim 1, wherein:

said arbitrarily selected region is an arbitrary one line crossing to the propagating direction of said light of said one line emitted from said light emitting means.

4. A displaying device in accordance with claim 1, wherein:

said waveguide array, comprising;

at least high refractive index regions and low refractive index regions, wherein;

said high refractive index regions are provided corresponding to the number of pixels composing said one line of said light emitting from said light emitting means in a designated array pitch, and

said light of said one line emitted from said light emitting means propagates in said corresponding high refractive index regions.

5. A displaying device in accordance with claim 1, wherein:

said waveguide array is formed by a polymeric material.

6. A displaying device in accordance with claim 1, wherein:

said waveguide array, further comprising;

a light absorbing layer for absorbing light from the outside on a supporting substrate.

7. A displaying device in accordance with claim 1, wherein:

said waveguide array, further comprising;

a supporting substrate made of a polymeric material;

a light absorbing layer for absorbing light from the outside formed on said supporting substrate;

a low refractive index region formed on said light absorbing layer; and

a layer, in which high refractive index regions and low refractive index regions are disposed alternately in a designated pitch, on said low refractive index region.

8. A displaying device in accordance with claim 1, wherein:

said light extracting means, comprising;

an antireflection layer for preventing light from the outside from reflecting.

9. A displaying device in accordance with claim 1, wherein:

said light extracting means, further comprising;

an optical material layer whose refractive index is changed by an external electric field; and

plural electrodes for generating an electric field by selecting a region of said optical material layer.

10. A displaying device in accordance with claim 9, wherein:

said plural electrodes are disposed so that a potential difference is generated in a region composing an arbitrary one line crossing to the propagating direction of said light of said one line emitted from said light emitting means.

11. A displaying device in accordance with claim 9, wherein:

said plural electrodes are composed of a pair of stripe-shaped electrodes, and one piece of said stripe-shaped electrodes has plural branches.

12. A displaying device in accordance with claim 9, wherein:

said region where an electric potential is given by said plural electrodes makes light emitted from said light emitting means extract to the outside from said optical material layer through said waveguide array, by changing the refractive index of said optical material layer at said region.

13. A displaying device in accordance with claim 9, wherein:

said plural electrodes are formed on the same plane surface.

14. A displaying device in accordance with claim 12, wherein:

said light extracting means, further comprising;

a light scattering layer for scattering said light extracted from said optical material layer.

15. A displaying device in accordance with claim 9, wherein:

said light extracting means, further comprising;

an antireflection layer for preventing light from the outside from reflecting.

16. A displaying device in accordance with claim 1, wherein:

said light extracting means corrects the light extracting efficiency at the time when said light is extracted corresponding to a loss of said light in said waveguide array.

17. A displaying device in accordance with claim 1, wherein:

said waveguide array and said light extracting means are formed by a flexible material that can be repeatedly rolled up and pulled out, and can be contained in a container.

18. A displaying device in accordance with claim 17, further comprising:

a detecting section that detects the boundary between the pulled out part being the exposed part from said container and the contained part in said container of said waveguide array and said light extracting means, wherein;

said light extracting means extracts light from only a region of said exposed part base on said detected result.

19. A displaying device in accordance with claim 1, wherein:

said light emitting means, comprising;

organic electro-luminescence (EL) layers for emitting light, wherein;

each of said organic EL layers is positioned between a transparent electrode and an opaque electrode.

20. A displaying device in accordance with claim 19, wherein:

said light emitting means, further comprising;

a transparent substrate;

a light shielding layer for shielding light from the outside provided on said transparent substrate;

a barrier layer for preventing impurity elements including in said transparent layer from entering other layers provided on said barrier layer; and

thin film transistors (TFTs) provided on said barrier layer.

21. A displaying device in accordance with claim 19, wherein:

said light emitting means provides said plural organic EL layers and TFTs for driving said plural organic EL layers corresponding to the number of pixels composing one line of emitting light.

22. A displaying device in accordance with claim 19, wherein:

said light emitting means, further comprising;

plural capacitors in which an inputted analog image signal is stored every pixel composing said one line;

wherein;

when said analog image signal of said one line was stored in said plural capacitors, voltages stored in said capacitors are applied to gate electrodes of said TFTs at the same time, and

said organic EL layers emit light of said one line at the same time.

23. A displaying device in accordance with claim 1, wherein:

said light emitting means inputs light of three colors R, G, and B to said waveguide array.

24. A displaying device in accordance with claim 1, wherein:

said light emitting means inputs a corrected image signal to said waveguide array corresponding to a loss of said light in said waveguide array.

25. A displaying device, comprising:

a light emitting means that emits light of one line of a displaying image by plural light emitting elements;

a waveguide array that propagates light inputted from said light emitting means from one end to the other end of said waveguide array; and

a light extracting means that extracts light propagating in said waveguide array from an arbitrarily one line crossing to the propagating direction of one line of said light emitted from said light emitting means, wherein;

said light extracting means, comprising;

a gray level controlling region which makes a part of light propagating through said waveguide array leak to the outside; and

a displaying region from which light controlled at said gray level controlling region is extracted.

26. A displaying device in accordance with claim 25, wherein:

said light extracting means, further comprising;

an antireflection layer for preventing light from the outside from reflecting.

27. A displaying device in accordance with claim 25, wherein:

said light extracting means, further comprising;

an optical material layer whose refractive index is changed corresponding to an electric field from the outside; and

plural electrodes for generating an electric field by selecting a region of said optical material layer.

28. A displaying device in accordance with claim 27, wherein:

said plural electrodes disposed at said gray level controlling region are positioned so that a potential difference is generated at a region of an area based on an inputted digital image signal.

29. A displaying device in accordance with claim 25, further comprising:

a light absorbing section for absorbing light leaked from said gray level controlling region.

30. A displaying device in accordance with claim 27, wherein:

said plural electrodes disposed at said displaying region are positioned so that a potential difference is generated in a region composing an arbitrary one line crossing to the propagating direction of light of one line emitted from said light emitting means.

31. A displaying device in accordance with claim 30, wherein:

said plural electrodes are composed of a pair of stripe-shaped electrodes, and one piece of said stripe-shaped electrodes has plural branches.

32. A displaying device in accordance with claim 27, wherein:

said plural electrodes are formed on the same plane surface.

33. A displaying device in accordance with claim 27, wherein:

at said region where said electric potential was given from said plural electrodes, said refractive index of said optical material layer is changed, and said light emitted from said light emitting means is extracted from said optical material layer through said waveguide array to the outside.

34. A displaying device in accordance with claim 27, wherein:

said light extracting means, further comprising;

a light scattering layer for scattering said light extracted from said optical material layer.

35. A displaying device in accordance with claim 27, wherein:

said light extracting means, further comprising;

an antireflection layer for preventing light from the outside from reflecting.

36. A displaying device in accordance with claim 25, wherein:

said light extracting means corrects the light extracting efficiency at the time when said light is extracted corresponding to a loss of said light in said waveguide array.

37. A displaying device in accordance with claim 25, wherein:

said light emitting means, comprising;

organic EL layers for emitting light, wherein;

each of said organic EL layers is positioned between a transparent electrode and an opaque electrode.

38. A displaying device in accordance with claim 37, wherein:

said light emitting means, further comprising;

a transparent substrate;

a light shielding layer for shielding light from the outside provided on said transparent substrate;

a barrier layer for preventing impurity elements including in said transparent layer from entering other layers provided on said barrier layer; and

TFTs provided on said barrier layer.

39. A displaying device in accordance with claim 37, wherein:

said light emitting means provides said plural organic EL layers and said TFTs for driving said plural organic EL layers corresponding to the number of pixels composing one line of emitting light, and

said TFTs are driven from the beginning of said one line in order, and

said plural organic EL layers emit light from the beginning of said one line in order.

40. A displaying device in accordance with claim 25, wherein:

said light emitting means inputs light of three colors R, G, and B to said waveguide array.

41. A displaying device in accordance with claim 25, wherein:

said light emitting means inputs a corrected image signal to said waveguide array corresponding to a loss of said light in said waveguide array.

42. A displaying device in accordance with claim 25, wherein:

said waveguide array, comprising;

at least high refractive index regions and low refractive index regions, wherein;

said high refractive index regions are provided corresponding to the number of pixels composing one line of light emitting from said light emitting means by a designated array pitch, and

light of one line emitted from said light emitting means is propagated in said corresponding high refractive index regions.

43. A displaying device in accordance with claim 25, wherein:

said waveguide array is formed by a polymeric material.

44. A displaying device in accordance with claim 25, wherein:

said waveguide array, further comprising;

a light absorbing layer for absorbing light from the outside on a supporting substrate.

45. A displaying device in accordance with claim 25, wherein:

said waveguide array, further comprising;

a supporting substrate formed by a polymeric material;

a light absorbing layer for absorbing light from the outside formed on said supporting substrate;

a low refractive index region formed on said light absorbing layer; and

a layer in which high refractive index regions and low refractive index regions are disposed alternately in a designated pitch on said low refractive index region.

46. A displaying device in accordance with claim 25, further comprising:

a light reflecting section for reflecting light propagated by said waveguide array at the other end of said waveguide array.

47. A displaying device in accordance with claim 25, wherein:

said waveguide array and said light extracting means are formed by a flexible material that can be repeatedly rolled up and pulled out, and can be contained in a container.

48. A displaying device in accordance with claim 25, further comprising:

a detecting section that detects the boundary between the pulled out part being an exposed part from said container and the contained part in said container of said waveguide array and said light extracting means, wherein;

said light extracting means extracts light from only a region of said exposed part base on said detected result.

49. A displaying method, comprising the steps of:

emitting light of one line of a displaying image by plural light emitting elements;

propagating emitted light from one end to the other end of a displaying region through a waveguide array; and

extracting said propagating light from an arbitrarily selected region;

wherein the light which is propagated through a waveguide array is extracted by said light extracting means to illuminate a display.

50. A displaying method in accordance with claim 49, wherein:

said arbitrarily selected region includes at least two or more pixels.

51. A displaying method in accordance with claim 49, wherein:

said arbitrarily selected region is an arbitrary one line crossing to the propagating direction of one line of said emitted light.

52. A displaying method in accordance with claim 49, wherein:

said extracting said propagating light, comprising the steps of;

generating a potential difference at a designated region of an optical material layer, whose refractive index is changed corresponding to an external electric field of said waveguide array in which light is propagating; and

changing said refractive index of said optical material layer by generating said potential difference.

53. A displaying method in accordance with claim 49, wherein:

said extracting said propagating light, further comprising the step of;

correcting light extracting efficiency at the time when said light is extracted corresponding to a loss of said light in said waveguide array.

54. A displaying method in accordance with claim 49, further comprising:

reflecting light that was propagated in said waveguide array at the other end of said displaying region.

55. A displaying method in accordance with claim 49, wherein:

said emitting light, comprising the steps of;

storing an inputted analog image signal in capacitors, every pixel composing one line of said inputted analog image signal;

applying said analog image signal to gate electrodes of TFTs at the same time, when said one line of said analog image signal was stored in said capacitors; and

making organic EL layers of said one line connecting to source-drain electrodes of said TFTs emit light at the same time.

56. A displaying method in accordance with claim 49, wherein:

at said emitting light,

three colors of R, G, and B are emitted.

57. A displaying method in accordance with claim 49, wherein:

at said emitting light,

light is emitted based on a corrected image signal corresponding to a loss of said light in said waveguide array.

58. A displaying method, comprising the steps of:

emitting light of one line of a displaying image by plural light emitting elements;

propagating said emitted light from one end to the other end of a waveguide array;

leaking a part of said propagating light at a gray level controlling region; and

extracting light controlled at said gray level controlling region from an arbitrarily one line crossing to the propagating direction of one line of said light.

59. A displaying method in accordance with claim 58, further comprising the step of:

absorbing light leaked at said gray level controlling region.

60. A displaying method in accordance with claim 58, wherein:

said leaking light and said extracting light, comprising the steps of;

generating a potential difference at a designated region of an optical material layer, whose refractive index is changed corresponding to an external electric field of said waveguide array in which light is propagating; and

changing said refractive index of said optical material layer by generating said potential difference.

61. A displaying method in accordance with claim 58, wherein:

said leaking light and said extracting light, comprising the step of;

generating a potential difference at a region of an area based on an inputted digital image signal.

62. A displaying method in accordance with claim 58, wherein:

said extracting light, further comprising the step of;

correcting light extracting efficiency at the time when said light is extracted corresponding to a loss of said light in said waveguide array.

63. A displaying method in accordance with claim 58, wherein:

said emitting light, comprising the steps of;

driving switching elements provided corresponding to pixels composing one line of emitting light from one end of said one line in order; and

making organic EL layers connecting to one end of said switching elements emit light from said one end in order.

64. A displaying method in accordance with claim 58, wherein:

at said emitting light,

three colors of R, G, and B are emitted.

65. A displaying method in accordance with claim 58, wherein:

at said emitting light,

light is emitted based on a corrected image signal corresponding to a loss of said light in said waveguide array.

66. A displaying method in accordance with claim 58, further comprising the step of:

reflecting light that was propagated in said waveguide array at the other end of said displaying region.

67. A manufacturing method of a displaying device, comprising the steps of:

forming a light emitting section that emits light of one line of a displaying image by plural light emitting elements;

forming a waveguide array that propagates light emitted from said light emitting section from one end to the other end of a displaying region; and

forming a light extracting section that extracts said propagating light from an arbitrarily selected region;

wherein the light which is propagated through a waveguide array is extracted by said light extracting means to illuminate a display.

68. A manufacturing method of a displaying device in accordance with claim 67, wherein:

said forming said waveguide array, comprising the step of;

forming a photosensitive acrylic resin having a polymer property on all surface of a supporting substrate made of a material having a polymer property by a spin coating method.

69. A manufacturing method of a displaying device in accordance with claim 68, wherein:

said forming said waveguide array, further comprising the steps of;

forming high refractive index regions by exposing and etching said photosensitive acrylic resin coated on said supporting substrate;

forming low refractive index regions by coating a low refractive index material having a polymer property on said supporting substrate on which said high refractive index regions were formed by the spin coating method; and

exposing the upper surfaces of said high refractive index regions by polishing the coated surface.

70. A manufacturing method of a displaying device in accordance with claim 68, wherein:

said forming said light extracting means, comprising the steps of;

forming a light scattering layer by a light scattering material having a polymer property on a transparent substrate having a plastic property;

coating a transparent electrode material on all surface of said transparent substrate on which said light scattering layer was formed by a spattering method;

forming plural electrodes by exposing and etching said transparent substrate on which said transparent electrode material was coated;

coating polyimide on all surface of said supporting substrate on which said plural electrodes were formed by the spin coating method;

forming an alignment layer by heating and rubbing said coated polyimide; and

forming a liquid crystal layer on said supporting substrate on which said alignment layer was formed.

71. A manufacturing method of a displaying device in accordance with claim 67, wherein:

said forming said light extracting means, further comprising the steps of;

forming an optical material whose refractive index is changed corresponding to an external electric field on said waveguide array; and

forming plural electrodes on said optical material.

72. A manufacturing method of a displaying device in accordance with claim 67, wherein:

said forming said light emitting section, comprising the steps of;

forming TFT driving circuits for driving said light emitting elements on a transparent substrate having a glass property; and

forming said light emitting elements on said transparent substrate on which said TFT driving circuits were formed.

73. A manufacturing method of a displaying device in accordance with claim 67, wherein:

said light omitting elements are organic EL elements.

74. A manufacturing method of a displaying device in accordance with claim 67, wherein:

said forming said light emitting section, comprising the steps of;

forming TFT driving circuits for driving said light emitting elements on a transparent substrate having a glass property;

forming a planalization layer for making the surface of said transparent substrate on which said TFT driving circuits were formed plane by using a transparent insulating material;

forming transparent electrodes that connect said TFT driving circuits and said light emitting elements by opening contact holes at a part of said planarization layer;

forming organic EL layers on said transparent electrodes;

forming opaque electrodes on said organic EL layers; and

forming a sealing layer for covering all of said transparent electrodes.