Liquid crystal display

• US 6,281,952 B1
• Filed: 12/22/1998
• Issued: 08/28/2001
• Est. Priority Date: 12/26/1997
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Okamoto, Masayuki, Mitsui, Seiichi, Hiraki, Hajime
• Primary Examiner(s): Parker, Kenneth
• Assistant Examiner(s): Duong, Tai V.
• Application Number:
  US09/217,931
• Time in Patent Office: 980 Days
• Field of Search: 349/12, 349/61, 349/106, 349/117, 349/119, 349/128, 349/129, 349/130, 349/141, 349/165, 349/180, 349/191, 345/104
• US Class Current: 349/12
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 1/133753 with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
• CPC Class Codes: G02F 2202/04 dye

Abstract

A liquid crystal display is furnished with: a liquid crystal display element having a pair of substrates, to which alignment members are provided to their respective opposing surfaces, and a liquid crystal layer sandwiched by the pair of substrates; an alignment mechanism for providing at least two different director configurations simultaneously on different arbitrary regions used for display in the liquid crystal layer; and a reflection film provided to at least one of the different arbitrary regions showing different director configurations; wherein the different arbitrary regions showing different director configurations are used for a reflection display section for showing reflection display and a transmission display section for showing transmission display, respectively. Examples of the alignment mechanism include an alignment film to which the alignment treatment is applied in different orientations in the reflection display section and transmission display section, respectively, an insulation film having different film thicknesses in the reflection display section and transmission display section, and so forth.

Claims

1. A liquid crystal display comprising:

a liquid crystal display element having a pair of substrates, to which alignment means are provided to their respective opposing surfaces, and a liquid crystal layer sandwiched by said pair of substrates;

an alignment mechanism for providing at least two different director configurations simultaneously on different arbitrary regions used for display in said liquid crystal layer; and

reflecting means provided to at least one of said different arbitrary regions showing different director configurations,

wherein said different arbitrary regions showing different director configurations are used for a reflection display section for showing reflection display and a transmission display section for showing transmission display, respectively.

2. The liquid crystal display of claim 1, wherein said alignment mechanism serves as display content overwriting means for overwriting a display content with an evolution of time.

3. The liquid crystal display of claim 1, wherein said alignment mechanism is said pair of substrates of said liquid crystal display provided with said alignment means;

wherein said alignment means is provided such that, in a region of at least one of said substrates touching a region of said liquid crystal layer used for display, at least two different director directions are imparted to a director configuration of said liquid crystal layer at an interface with said region of said substrate.

4. The liquid crystal display of claim 1, wherein an area of said reflection display section accounts for 30% or above and 90% or less of a total of areas of said reflection display section and said transmission display section.

5. The liquid crystal display of claim 1, wherein, when said transmission display section shows light display, said reflection display section also shows light display, and when said transmission display section shows dark display, said reflection display section also shows dark display.

6. The liquid crystal display of claim 1, wherein said liquid crystal layer is made of liquid crystal composition prepared by blending a dichroic dye with liquid crystal.

7. The liquid crystal display of claim 1, further comprising a polarization plate provided to at least one of said pair of substrates on a surface which does not touch said liquid crystal layer.

8. The liquid crystal display of claim 7, further comprising voltage applying means for applying a voltage to said liquid crystal layer in such a manner that display light on said reflecting means of said reflection display section has a phase difference of approximately 90°

between the light display and the dark display, and display light going out from said liquid crystal layer in said transmission display section has a phase difference of approximately 180°

between the light display and dark display.

9. The liquid crystal display of claim 7, wherein said liquid crystal layer is aligned with a twist between said pair of substrates at a twist angle in a range between 60°

and 100°

inclusive.

10. The liquid crystal display of claim 7, wherein said liquid crystal layer is aligned with a twist between said pair of substrates at a twist angle in a range between 0°

and 40°

inclusive.

11. The liquid crystal display of claim 1, wherein said liquid crystal display element shows the display by changing the director configuration of said liquid crystal layer by rotating liquid crystal molecules in parallel with said pair of substrates in at least one of said reflection display section and said transmission display section.

12. The liquid crystal display of claim 11, wherein said liquid crystal display element includes voltage applying means for generating an electric field in said liquid crystal layer along an in-plane direction of said pair of substrates in one of said reflection display section and said transmission display section.

13. The liquid crystal display of claim 1, wherein at least one of said pair of substrates includes a vertical aligning alignment film on a surface touching said liquid crystal layer at a region corresponding to at least one of said reflection display section and said transmission display section.

14. The liquid crystal display of claim 1, wherein, in at least one of said pair of substrates, a region corresponding to said reflection display section is thicker than a region corresponding to said transmission display section.

15. The liquid crystal display of claim 14, wherein at least one of said pair of substrates includes an insulation film at least on the region corresponding to said reflection display section, said insulation film being thicker in the region corresponding to said reflection display section than in the region corresponding to said transmission display section.

16. The liquid crystal display of claim 1, wherein, on one of said pair of substrates, among regions making up a display region of each pixel, at least a region corresponding to said transmission display section is provided with a color filter having a transmission color.

17. The liquid crystal display of claim 16, wherein, among regions making up said display region, at least part of a region corresponding to said reflection display section is provided with a color filter having brightness equivalent to brightness of said color filter provided to the region of said substrate corresponding to said transmission display section.

18. The liquid crystal display of claim 16, wherein, among regions making up said display region, at least part of a region corresponding to said reflection display section is provided with a color filter having a transmission color brighter than the transmission color of said color filter provided to the region of said substrate corresponding to said transmission display section.

19. The liquid crystal display of claim 16, wherein a part of said reflection display section does not show color display, and an area of said part is set in accordance with luminous transmittance of the transmission color of said color filter.

20. The liquid crystal display of claim 1, wherein, on one of said pair of substrates, among regions making up a display region of each pixel, at least a region corresponding to said reflection display section is provided with a color filter having a transmission color.

21. The liquid crystal display of claim 20, wherein, a part of said transmission display section does not show color display, and an area of said part is set in accordance with luminous transmittance of the transmission color of said color filter.

22. The liquid crystal display of claim 20, wherein, among regions making up said display region, at least part of a region corresponding to said transmission display section is provided with a color filter having a transmission color with chroma at least as good as chroma of the color filter provided to the region corresponding to said reflection display section.

23. The liquid crystal display of claim 1, further comprising pressed coordinate detecting type input means, superimposed on a display surface, which, when pressed, detect a pressed coordinate position.

24. The liquid crystal display of claim 1, further comprising a lighting device for emitting light to said liquid crystal display element from behind, said lighting device also serving as display surface luminance changing means for changing luminance on a display surface.

25. The liquid crystal display of claim 24, wherein said lighting device changes the luminance on said display surface in response to luminance of an observer in such a manner as to attain perceived brightness ranging from 10 brils inclusive to 30 brils exclusive.

26. The liquid crystal display of claim 24, further comprising pressed coordinate detecting type input means, superimposed on said display surface, which, when pressed, detect a pressed coordinate position, wherein said lighting device changes the luminance on said display surface in association with an output signal from said pressed coordinate detecting type input means.

27. The liquid crystal display of claim 1, further comprising pressed coordinate detecting type input means, superimposed on a display surface, which, when pressed, detected a pressed coordinate position when being pressed, wherein said alignment mechanism changes the director configuration of said liquid crystal layer in at least one of said reflection display section and said transmission display section in association with an output signal from said pressed coordinate detecting type input means.

28. The liquid crystal display of claim 1, further comprising pressed coordinate detecting type input means, superimposed on a display surface, which, when pressed, detect a pressed coordinate position when being pressed and a polarization plate, said polarization plate, said pressed coordinate detecting type input means, and said liquid crystal display element being provided in that order.

29. The liquid crystal display of claim 1, wherein said alignment mechanism is a plurality of voltage applying means for applying a voltage to said liquid crystal display, each of said plurality of voltage applying means being electrically isolated between said reflection display section and said transmission display section, so that a voltage is applied to each of said voltage applying means separately in said reflection display section and said transmission display section.

30. A liquid crystal display comprising a liquid crystal display element having a pair of substrates, to which alignment means are provided to their respective opposing surfaces, and a liquid crystal layer sandwiched by said pair of substrates, wherein:

a region used for display in said liquid crystal layer is composed of regions having at least two different thicknesses of said liquid crystal layer;

said regions having at least two different thicknesses are used for a reflection display section and a transmission display section, respectively;

reflecting means is provided at least to said reflection display section; and

the thickness of the liquid crystal layer is thinner in said reflection display section than in said transmission display section.

31. The liquid crystal display of claim 30, wherein said alignment mechanism is said pair of substrates of said liquid crystal display provided with said alignment means;

wherein said alignment means is provided such that, in a region of at least one of said substrates touching a region of said liquid crystal layer used for display, at least two different director directions are imparted to a director configuration of said liquid crystal layer at an interface with said region of said substrate.

32. The liquid crystal display of claim 30, wherein an area of said reflection display section accounts for 30% or above and 90% or less of a total of areas of said reflection display section and said transmission display section.

33. The liquid crystal display of claim 30, wherein, when said transmission display section shows light display, said reflection display section also shows light display, and when said transmission display section shows dark display, said reflection display section also shows dark display.

34. The liquid crystal display of claim 30, wherein said liquid crystal layer is made of liquid crystal composition prepared by blending a dichroic dye with liquid crystal.

35. The liquid crystal display of claim 30, further comprising a polarization plate provided to at least one of said pair of substrates on a surface which does not touch said liquid crystal layer.

36. The liquid crystal display of claim 35, further comprising voltage applying means for applying a voltage to said liquid crystal layer in such a manner that display light on said reflecting means of said reflection display section has a phase difference of approximately 90°

between the light display and the dark display, and display light going out from said liquid crystal layer in said transmission display section has a phase difference of approximately 180°

between the light display and dark display.

37. The liquid crystal display of claim 35, wherein said liquid crystal layer is aligned with a twist between said pair of substrates at a twist angle in a range between 60°

and 100°

inclusive.

38. The liquid crystal display of claim 35, wherein said liquid crystal layer is aligned with a twist between said pair of substrates at a twist angle in a range between 0°

and 40°

inclusive.

39. The liquid crystal display of claim 30, wherein said liquid crystal display element shows the display by changing the director configuration of said liquid crystal layer by rotating liquid crystal molecules in parallel with said pair of substrates in at least one of said reflection display section and said transmission display section.

40. The liquid crystal display of claim 39, wherein said liquid crystal display element includes voltage applying means for generating an electric field in said liquid crystal layer along an in-plane direction of said pair of substrates in one of said reflection display section and said transmission display section.

41. The liquid crystal display of claim 30, wherein at least one of said pair of substrates includes a vertical aligning alignment film on a surface touching said liquid crystal layer at a region corresponding to at least one of said reflection display section and said transmission display section.

42. The liquid crystal display of claim 30, wherein, in at least one of said pair of substrates, a region corresponding to said reflection display section is thicker than a region corresponding to said transmission display section.

43. The liquid crystal display of claim 42, wherein at least one of said pair of substrates includes an insulation film at least on the region corresponding to said reflection display section, said insulation film being thicker in the region corresponding to said reflection display section than in the region corresponding to said transmission display section.

44. The liquid crystal display of claim 30, wherein, on one of said pair of substrates, among regions making up a display region of each pixel, at least a region corresponding to said transmission display section is provided with a color filter having a transmission color.

45. The liquid crystal display of claim 44, wherein, among regions making up said display region, at least part of a region corresponding to said reflection display section is provided with a color filter having brightness equivalent to brightness of said color filter provided to the region of said substrate corresponding to said transmission display section.

46. The liquid crystal display of claim 44, wherein, among regions making up said display region, at least part of a region corresponding to said reflection display section is provided with a color filter having a transmission color brighter than the transmission color of said color filter provided to the region of said substrate corresponding to said transmission display section.

47. The liquid crystal display of claim 44, wherein a part of said reflection display section does not show color display, and an area of said part is set in accordance with luminous transmittance of the transmission color of said color filter.

48. The liquid crystal display of claim 30, wherein, on one of said pair of substrates, among regions making up a display region of each pixel, at least a region corresponding to said reflection display section is provided with a color filter having a transmission color.

49. The liquid crystal display of claim 48, wherein a part of said transmission display section does not show color display, and an area of said part is set in accordance with luminous transmittance of the transmission color of said color filter.

50. The liquid crystal display of claim 48, wherein, among regions making up said display region, at least part of a region corresponding to said transmission display section is provided with a color filter having a transmission color with chroma at least as good as chroma of the color filter provided to the region corresponding to said reflection display section.

51. The liquid crystal display of claim 30, further comprising pressed coordinate detecting type input means, superimposed on a display surface, which, when pressed, detect a pressed coordinate position.

52. The liquid crystal display of claim 30, further comprising a lighting device for emitting light to said liquid crystal display element from behind, said lighting device also serving as display surface luminance changing means for changing luminance on a display surface.

53. The liquid crystal display of claim 52, wherein said lighting device changes the luminance on said display surface in response to luminance of an observer in such a manner as to attain perceived brightness ranging from 10 brils inclusive to 30 brils exclusive.

54. The liquid crystal display of claim 52, further comprising pressed coordinate detecting type input means, superimposed on said display surface, which, when pressed, detect a pressed coordinate position, wherein said lighting device changes the luminance on said display surface in association with an output signal from said pressed coordinate detecting type input means.

55. The liquid crystal display of claim 30, further comprising pressed coordinate detecting type input means, superimposed on a display surface, which, when pressed, detect a pressed coordinate position, and voltage applying means for applying a voltage to said liquid crystal layer, wherein:

said voltage applying means applies a voltage to said liquid crystal layer in association with an output signal from said pressed coordinate detecting type input means.

56. The liquid crystal display of claim 30, further comprising pressed coordinate detecting type input means, superimposed on a display surface, which, when pressed, detect a pressed coordinate position, and a polarization plate, said polarization plate, said pressed coordinate detecting type input means, and said liquid crystal display element being provided in that order.

57. The liquid crystal display of claim 30, wherein said alignment mechanism is a plurality of voltage applying means for applying a voltage to said liquid crystal display, each of said plurality of voltage applying means being electrically isolated in said reflection display section and said transmission display section, so that a voltage is applied to each of said voltage applying means separately in said reflection display section and said transmission display section.