Optical modulation apparatus using ferroelectric liquid crystal and low-resistance portions of column electrodes

• US 4,824,218 A
• Filed: 04/02/1987
• Issued: 04/25/1989
• Est. Priority Date: 04/09/1986
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yoshioka, Seishiro, Shindo, Hitoshi, Enari, Masahiko, Kuno, Mitsutoshi, Shimoda, Isamu, Kaneko, Shuzo, Toyono, Tsutomu
• Primary Examiner(s): Miller, Stanley D.
• Assistant Examiner(s): Gallivan, Richard F.
• Application Number:
  US07/033,578
• Time in Patent Office: 754 Days
• Field of Search: 350/333, 350/336, 350/350 S, 340/765, 340/784, 340/805
• US Class Current: 349/37
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/141 using ferroelectric liquid crystals
• CPC Class Codes: G02F 2203/30 Gray scale
• CPC Class Codes: G09G 2310/0297 Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns
• CPC Class Codes: G09G 2310/06 Details of flat display driving waveforms
• CPC Class Codes: G09G 2310/061 for resetting or blanking
• CPC Class Codes: G09G 2310/063 Waveforms for resetting the whole screen at once
• CPC Class Codes: G09G 2320/0209 Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display
• CPC Class Codes: G09G 2320/0223 Compensation for problems related to R-C delay and attenuation in electrodes of matrix panels, e.g. in gate electrodes or on-substrate video signal electrodes
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/2014 by modulation of the duration of a single pulse during which the logic level remains constant
• CPC Class Codes: G09G 3/207 by domain size control G09G3/3637 takes precedence
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3637 with intermediate tones displayed by domain size control domain size control in flat matrix panels other than liquid crystal displays having memory effects G09G3/207
• CPC Class Codes: G09G 3/3685 Details of drivers for data electrodes
• CPC Class Codes: G09G 3/3696 Generation of voltages supplied to electrode drivers

Abstract

A driving system is disclosed, wherein a potential gradient is formed in a pixel and is utilized for driving. Particularly, there is disclosed an optical modulation apparatus, comprising: a first substrate having thereon a conductor film, and a plurality of transmission lines disposed electrically connected to the conductor film; a second substrate; an optical modulation material disposed between the first and second substrate; and means for supplying a pair of electric signals in mutually opposite transmission directions to neighboring transmission lines among the plurality of transmission lines.

Claims

1. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a conductor film, and a plurality of first electrodes disposed electrically connected to the conductor film;

a second substrate having thereon a plurality of second electrodes; and

an optical modulation material disposed between the first and second substrates;

a scanning line driver circuit comprising means for supplying a scanning line to the second electrodes; and

a data line driver circuit comprising means for supplying driving signals to odd-numbered electrodes among the first electrodes in phase with the scanning signal and means for supplying data signals to even-numbered electrodes among the first electrodes in phase with the scanning signal.

2. An apparatus according to claim 1, wherein the even-numbered (or odd-numbered) electrodes among the first electrodes are connected to a reference potential supply when data signals are supplied to the odd-numbered (or even-numbered) electrodes among the first electrodes.

3. An apparatus according to claim 1, wherein a scanning selection signal is sequentially supplied to a selected scanning electrode among the second electrodes, and data signals are time-consecutively supplied to the odd-numbered electrodes and the even-numbered electrodes among the first electrodes in phase with the scanning selection signal.

4. An apparatus according to claim 1, wherein a scanning selection signal is sequentially supplied to a selected scanning electrode among the second electrodes, and data signals are supplied to the odd-numbered electrodes and the even-numbered electrodes for each prescribed period.

5. An apparatus according to claim 4, wherein said prescribed period corresponds to a period of one frame or one field of video signals.

6. An apparatus according to claim 1, wherein said data signals are pulse signals having a pulse duration corresponding to given gradation data.

7. An apparatus according to claim 1, wherein said data signals are pulse signals having a number of pulses corresponding to given gradation data.

8. An apparatus according to claim 1, wherein said data signals are pulse signals having a peak value corresponding to given gradation data.

9. An apparatus according to claim 1, wherein said first electrodes have a sheet resistivity smaller than that of the conductor film.

10. An apparatus according to claim 1, wherein said conductor film has a sheet resistivity of 10² Ω

/□

or higher.

11. An apparatus according to claim 1, wherein said optical modulation material is a ferroelectric liquid crystal.

12. An apparatus according to claim 11, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

13. An apparatus according to claim 1, wherein said data line driver circuit comprises two memory circuits.

14. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a first stripe conductor film and at least two transmission lines disposed electrically connected to the first conductor film;

a second substrate having thereon a second stripe conductor film disposed opposite to the first stripe conductor film; and

an optical modulation material disposed between the first and second substrates;

means for supplying a data signal to a first transmission line among said at least two transmission lines in phase with a scanning signal supplied to the second conductor film while connecting a second transmission line among said at least two transmission lines to a reference potential supply; and

means for supplying a data signal to a second transmission line among said at least two transmission lines in phase with a scanning signal supplied to the second conductor film while connecting a first transmission line among said at least two transmission lines to a reference potential supply.

15. An apparatus according to claim 14, wherein said data signal is a pulse signal having a pulse duration corresponding to given gradation data.

16. An apparatus according to claim 14, wherein said data signal is a pulse signal having a number of pulses corresponding to given gradation data.

17. An apparatus according to claim 14, wherein said data signal is a pulse signal having a peak value corresponding to given gradation data.

18. An apparatus according to claim 14, wherein the transmission lines have a sheet resistivity smaller than that of the conductor film.

19. An apparatus according to claim 14, wherein said conductor film has a sheet resistivity of 10² Ω

/□

or higher.

20. An apparatus according to claim 14, wherein said optical modulation material is a ferroelectric liquid crystal.

21. An apparatus according to claim 20, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

46. An apparatus according to claim 14, 22, 30 or 38, wherein the maximum of the scanning signal pulse and the data signal pulse is substantially equal to the threshold voltage of the optical modulation material in the neighborhood of the center of a pixel defined as a superposed region between the conductor film on the first substrate and the conductor film or electrode on the second substrate.

22. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a first stripe conductor film and at least two transmission lines disposed electrically connected to the first conductor film;

a second substrate having thereon a second stripe conductor film disposed opposite to the first stripe conductor film; and

an optical modulation material disposed between the first and second substrates;

means for supplying a scanning signal to a first transmission line among said at least two transmission lines while connecting a second transmission line among said at least two transmission lines to a reference potential supply;

means for supplying a scanning signal to a second transmission line among said at least two transmission lines while connecting a first transmission line among said at least two transmission lines to a reference potential supply; and

means for supplying a data signal to said second stripe conductor film in phase with the scanning signal.

23. An apparatus according to claim 22, wherein said data signal is a pulse signal having a pulse duration corresponding to given gradation data.

24. An apparatus according to claim 22, wherein said data signal is a pulse signal having a number of pulses corresponding to given gradation data.

25. An apparatus according to claim 22, wherein said data signal is a pulse signal having a peak value corresponding to given gradation data.

26. An apparatus according to claim 22, wherein the transmission lines have a sheet resistivity smaller than that of the conductor film.

27. An apparatus according to claim 22, wherein said conductor film has a sheet resistivity of 10² Ω

/□

or higher.

28. An apparatus according to claim 22, wherein said optical modulation material is a ferroelectric liquid crystal.

29. An apparatus according to claim 28, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

30. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a first stripe conductor film, and at least two transmission lines disposed electrically connected to the first conductor film including a first transmission line and a second transmission line;

a second substrate having thereon a second stripe conductor film disposed opposite to the first stripe conductor film, and at least two transmission lines disposed electrically connected to the second conductor film including a third transmission line and a fourth transmission line; and

an optical modulation material disposed between the first and second substrates;

means for supplying a scanning signal to the first transmission line while connecting the second transmission line to a reference potential supply, and supplying a data signal to the third transmission line in phase with the scanning signal while connecting the fourth transmission line to a reference potential supply; and

means for supplying a scanning signal to the first transmission line while connecting the second transmission line to a reference potential supply, and supplying a data signal to the fourth transmission line in phase with the scanning signal while connecting the third transmission line to a reference potential supply.

31. An apparatus according to claim 30, wherein said data signals are pulse signals having a pulse duration corresponding to given gradation data.

32. An apparatus according to claim 30, wherein said data signals are pulse signals having a number of pulses corresponding to given gradation data.

33. An apparatus according to claim 30, wherein said data signals are pulse signals having a peak value corresponding to given gradation data.

34. An apparatus according to claim 30, wherein said first electrodes have a sheet resistivity smaller than that of the conductor film.

35. An apparatus according to claim 30, wherein said conductor film has a sheet resistivity of 10² Ω

/□

or higher.

36. An apparatus according to claim 30, wherein said optical modulation material is a ferroelectric liquid crystal.

37. An apparatus according to claim 36, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

38. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a first stripe conductor film, and at least two transmission lines disposed electrically connected to the first conductor film including a first transmission line and a second transmission line;

a second substrate having thereon a second stripe conductor film disposed opposite to the first stripe conductor film, and at least two transmission lines disposed electrically connected to the second conductor film including a third transmission line and a fourth transmission line; and

an optical modulation material disposed between the first and second substrates;

means for supplying a scanning signal to the first transmission line while connecting the second transmission line to a reference potential supply, and supplying a data signal to the third transmission line in phase with the scanning signal while connecting the fourth transmission line to a reference potential supply;

means for supplying a scanning signal to the first transmission line while connecting the second transmission line to a reference potential supply, and supplying a data signal to the fourth transmission line in phase with the scanning signal while connecting the third transmission line to a reference potential supply;

means for supplying a scanning signal to the second transmission line while connecting the first transmission line to a reference potential supply, and supplying a data signal to the third transmission line in phase with the scanning signal while connecting the fourth transmission line to a reference potential supply; and

means for supplying a scanning signal to the second transmission line while connecting the first transmission line to a reference potential supply, and supplying a data signal to the fourth transmission line in phase with the scanning signal while connecting the third transmission line to a reference potential supply.

39. An apparatus according to claim 38, wherein said data signals are pulse signals having a pulse duration corresponding to given gradation data.

40. An apparatus according to claim 38, wherein said data signals are pulse signals having a number of pulses corresponding to given gradation data.

41. An apparatus according to claim 38, wherein said data signals are pulse signals having a peak value corresponding to given gradation data.

42. An apparatus according to claim 38, wherein said first electrodes have a sheet resistivity smaller than that of the conductor film.

43. An apparatus according to claim 38, wherein said conductor film has a sheet resistivity of 10² Ω

/□

higher.

44. An apparatus according to claim 38, wherein said optical modulation material is a ferroelectric liquid crystal.

45. An apparatus according to claim 44, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

47. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate, a second substrate, and an optical modulation material disposed between the first and second substrates, the first substrate having thereon a set of scanning electrodes each comprising a conductor film and at least two low-resistivity transmission lines electrically connected to the conductor film, the second substrate having a set of data electrodes; and

driving means comprising a scanning driver circuit for applying a scanning signal serially to each of the scanning electrodes and a data driver circuit for applying data signals in parallel to the data electrodes, wherein the data driver circuit comprises a first memory circuit for memorizing odd-numbered data signals and a second memory circuit for memorizing even-numbered data signals.

48. An apparatus according to claim 47, wherein a data signal supplied from the data driver circuit to the data electrodes is a pulse signal having a peak value corresponding to given gradation data.

49. An apparatus according to claim 47, wherein a data signal supplied from the data driver circuit to the data electrodes is a pulse signal having a pulse duration corresponding to given gradation data.

50. An apparatus according to claim 47, wherein a data signal supplied from the data driver circuit to the data electrode is a pulse signal having a number of pulses corresponding to given gradation data.

51. An apparatus according to claim 47, wherein said transmission lines have a sheet resistivity smaller than that of the conductor film.

52. An apparatus according to claim 47, wherein said conductor film has a sheet resistivity of 10² Ω

/□

or higher.

53. An apparatus according to claim 47, wherein said optical modulation material is a ferroelectric liquid crystal.

54. An apparatus according to claim 53, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

55. An apparatus according toclaim 48, wherein the output of said first memory circuit and the output of said second memory circuit comprises a data signal potential.

56. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a plurality of stripe conductor films, and a first and a second transmission electrode disposed along the longitudinal direction of each stripe conductor film;

a second substrate having thereon a plurality of stripe electrodes disposed opposite to and intersecting with the stripe conductor films; and

an optical modulation material disposed between the first and second substrates; and

means for sequentially supplying a scanning signal of plural levels to the first transmission electrodes, and applying data signals to the stripe electrodes in phase with the scanning signal while connecting the second transmission electrodes to a reference potential supply.

57. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a plurality of first stripe conductor films, and a first and a second transmission electrode disposed along the longitudinal direction of each first stripe conductor film;

a second substrate having thereon a plurality of second stripe conductor films disposed opposite to and intersecting with the stripe conductor films and a third and a fourth transmission electrode disposed along the longitudinal direction of each second stripe conductor film; and

an optical modulation material disposed between the first and second substrates; and

means for sequentially supplying a scanning signal of plural levels to the first transmission electrodes while connecting the second transmission electrodes to a reference potential supply, and applying data signals of plural levels to the third transmission electrodes in phase with the scanning signal while connecting the fourth transmission electrodes to a reference potential supply.

58. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a plurality of stripe conductor films, and a first and a second transmission electrode disposed along the longitudinal direction of each stripe conductor film;

a second substrate having thereon a plurality of stripe electrodes disposed opposite to and intersecting with the stripe conductor films; and

an optical modulation material disposed between the first and second substrates;

means for sequentially supplying a scanning signal of plural levels to the first transmission electrodes, and applying data signals to the stripe electrodes in phase with the scanning signal while connecting the second transmission electrodes to a reference potential supply; and

means for setting the reference potential of the reference potential supply to 1/2 of the threshold potential of the optical modulation material.

59. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a plurality of first stripe conductor films, and a first and a second transmission electrode disposed along the longitudinal direction of each first stripe conductor film;

a second substrate having thereon a plurality of second stripe conductor films disposed opposite to and intersecting with the stripe conductor films and a third and a fourth transmission electrode disposed along the longitudinal direction of each second stripe conductor film; and

an optical modulation material disposed between the first and second substrates;

means for sequentially supplying a scanning signal of plural levels to the first transmission lines while connecting the second transmission lines to a reference potential supply;

means for applying data signals of plural levels to the third transmission lines in phase with the scanning signal while connecting the fourth transmission electrodes to a reference potential supply; and

means for setting the reference potential of the reference potential supply to 1/2 of the threshold potential of the optical modulation material.

60. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a plurality of stripe conductor films, and a first and a second transmission electrode disposed along the longitudinal direction of each stripe conductor film;

a second substrate having thereon a plurality of stripe electrodes disposed opposite to and intersecting with the stripe conductor films; and

an optical modulation material disposed between the first and second substrates;

means for sequentially supplying a scanning signal of plural levels to the first transmission lines;

means for applying data signals to the stripe electrodes in phase with the scanning signal; and

means for connecting the second transmission electrodes to a reference potential supply through a resistor having a resistance substantially equal to that between the first transmission electrode and the second transmission electrode.

61. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate having thereon a plurality of first stripe conductor films, and a first and a second transmission electrode disposed along the longitudinal direction of each first stripe conductor film;

a second substrate-having thereon a plurality of second stripe conductor films disposed opposite to and intersecting with the stripe conductor films and a third and a fourth transmission electrode disposed along the longitudinal direction of each second stripe conductor film; and

an optical modulation material disposed between the frst and second substrates;

means for sequentially supplying a scanning signal of plural levels to the first transmission electrodes;

means for connecting the second transmission electrodes to a reference potential supply through a resistor having a resistance substantially equal to that between the first transmission electrode and the second transmission electrode;

means for supplying data signals to the third transmission electrodes in phase with the scanning signal, and

means for connecting the third transmission electrodes to a reference potential supply through a resistor having a resistance substantially equal to that between the third transmission electrode and the fourth transmission electrode.

62. An optical modulation apparatus, comprising:

an optical modulation device comprising;

a first substrate having thereon a conductor film and at least two transmission electrodes connected to the conductor film, a second substrate having thereon a plurality of stripe electrodes disposed opposite to and intersecting with the transmission electrodes, and an optical modulation material disposed between the first and second substrates;

means for sequentially supplying a scanning signal to the transmission electrodes;

means for connecting a transmission electrode not supplied with the scanning signal to a reference potential supply;

means for supplying data signals to the stripe electrodes in phase with the scanning signal; and

means for providing said reference potential supply with a fixed bias voltage or a bias voltage proportional to gradation signals.

63. An optical modulation apparatus, comprising:

an optical modulation device comprising;

a first substrate having thereon a conductor film and at least two first transmission electrodes connected to the conductor film, a second substrate having thereon a conductor film disposed opposite to and intersecting with the transmission electrodes and at least two second transmission electrodes connected to the conductor film and disposed to intersect with the first transmission electrode, and an optical modulation material disposed between the first and second substrates;

means for sequentially supplying a scanning signal to the first transmission electrodes;

means for connecting a first transmission electrode not supplied with the scanning signal to a reference potential supply;

means for supplying data signals to the second transmission electrodes in phase with the scanning signal; and

means for providing said reference potential supply with a fixed bias voltage or a bias voltage proportional to gradation signals.

64. An optical modulation device, comprising:

a first substrate, a second substrate, and an optical modulation material disposed between the first and second substrates;

at least one of the first and second substrates having thereon a conductor film and a number M of low-resistivity transmission lines, at least one of the first and M-th transmission lines having been connected to a reference potential supply.

65. A device according to claim 64, wherein both the first and second substrates have thereon a conductor film and a plurality of low-resistivity transmission lines electrically connected to the conductor film.

66. A device according to claim 64, wherein a

scanning signal is supplied to the second to M-1-th transmission lines among the transmission lines.

67. A device according to claim 64, wherein data signals are supplied to the second to M-1-th transmission lines among the transmission lines.

68. A device according to claim 64, wherein said data signals are pulse signals having a pulse duration corresponding to given gradation data.

69. A device according to claim 64, wherein said data signals are pulse signals having a number of pulses corresponding to given gradation data.

70. A device according to claim 64, wherein said data signals are pulse signals having a peak value corresponding to given gradation data.

71. A device according to claim 64, wherein said conductor film has a sheet resistivity of 10² Ω

/□

or higher.

72. A device according to claim 64, wherein said optical modulation material is a ferroelectric liquid crystal.

73. A device according to claim 72, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

74. An optical modulation apparatus, comprising:

an optical modulation device comprising a first substrate, a second substrate, and an optical modulation material disposed between the first and second substrates;

at least one of the first and second substrates having thereon a conductor film having a resistivity and a plurality of low-resistivity transmission lines electrically connected to the conductor film;

means for applying a voltage exceeding the threshold voltage of the optical modulation material between the conductor film and a counter electrode opposite thereto; and

means for supplying a voltage signal to the transmission lines.

75. An apparatus according to claim 74, wherein the voltage signal supplied to the transmission lines is a scanning signal.

76. An apparatus according to claim 74, wherein the voltage signal supplied to the transmission lines is a data signal.

77. An apparatus according to claim 76, wherein said data signal is a pulse signal having a pulse duration corresponding to given gradation data.

78. An apparatus according to claim 76, wherein said data signal is a pulse signal having a number of pulses corresponding to given gradation data.

79. An apparatus according to claim 76, wherein said data signal is a pulse signal having a peak value corresponding to given gradation data.

80. An apparatus according to claim 74, wherein said conductor film has a sheet resistivity of 10² Ω

/□

or higher.

81. An apparatus according to claim 74, wherein said optical modulation material is a ferroelectric liquid crystal.

82. An apparatus according to claim 81, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

83. An optical modulation apparatus, comprising:

a first substrate having thereon a conductor film, and a plurality of transmission lines disposed electrically connected to the conductor film;

a second substrate;

an optical modulation material disposed between the first and second substrates; and

means for supplying a pair of electric signals in mutually opposite transmission directions to neighboring transmission lines among said plurality of transmission lines.

84. An apparatus according to claim 83 wherein one of said pair of electric signals is a scanning signal and the other electric signal is one supplied from a reference potential supply.

85. An apparatus according to claim 83, wherein said conductor film is disposed in the form of a stripe, along the length of which at least two transission lines are disposed electrically connected.

86. An apparatus according to claim 85, wherein neighboring transmission lines among said at least two transmission lines connected to each conductor film are supplied with electric signals in mutually opposite transmission directions.

87. An apparatus according to claim 85 wherein 2 transmission lines are electrically connected to the stripe conductor film.

88. An apparatus according to claim 85, wherein 3 transmission lines are electrically to the stripe conductor film.

89. An apparatus according to claim 83, wherein the second substrate is provided with a stripe electrode.

90. An apparatus according to claim 89, wherein the stripe electrode is supplied with a data signal.

91. An apparatus according to claim 90, wherein said data signal is a pulse signal having a pulse duration corresponding to given gradation data.

92. An apparatus according to claim 90, wherein said data signal is a pulse signal having a number of pulses corresponding to given gradation data.

93. An apparatus according to claim 90, wherein said data signal is a pulse signal having a peak value corresponding to given gradation data.

94. An apparatus according to claim 83, wherein said optical modulation material is a ferroelectric liquid crystal.

95. An apparatus according to claim 94, wherein said ferroelectric liquid crystal is a chiral smectic liquid crystal.

96. An apparatus according to claim 95, wherein said chiral smectic liquid crystal is formed in a layer thin enough to release the helical structure thereof.

97. An apparatus according to claim 83, wherein said conductor film has a sheet resistivity of 10 KΩ

/□

-1 MΩ

/□

.

98. An apparatus according to claim 83, wherein said transmission line has a sheet resistivity of 10² Ω

/□

or below. □