Microencapsulated electrophoretic electrostatically addressed media for drawing device applications

• US 20030067427A1
• Filed: 09/16/2002
• Published: 04/10/2003
• Est. Priority Date: 05/12/1998
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Albert, Jonathan D., Jacobson, Joseph M., Comiskey, Barrett, Wilcox, Russell J., Drzaic, Paul
• Granted Patent: US 6,738,050 B2
• Time in Patent Office: Days
• US Class Current: 345/84
• CPC Class Codes: B41J 3/4076 printing on rewritable, bistable "electronic paper" by a focused electric or magnetic field
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/133348 Charged particles addressed liquid crystal cells, e.g. controlled by an electron beam
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/1343 Electrodes reflective electrodes G02F1/133553
• CPC Class Codes: G02F 1/1345 Conductors connecting electrodes to cell terminals
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/16757 Microcapsules
• CPC Class Codes: G02F 2202/28 Adhesive materials or arrangements
• CPC Class Codes: G09F 9/302 characterised by the form or geometrical disposition of the individual elements
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field
• CPC Class Codes: H10K 10/462 Insulated gate field-effect transistors [IGFETs]
• CPC Class Codes: H10K 19/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic element specially adapted for rectifying, amplifying, oscillating or switching, covered by group H10K10/00
• CPC Class Codes: H10K 85/30 Coordination compounds
• CPC Class Codes: H10K 85/60 Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence

Abstract

A display includes an encapsulated display media, a rear electrode, and a movable electrode. The encapsulated display media comprises a plurality of capsules, each capsule comprising a plurality of particles dispersed in a fluid. The display media has a first surface and a second surface. The rear electrode is disposed adjacent the second surface of the display media. The movable electrode and the rear electrode apply an electric field across the display media.

Claims

1. A display comprising:

an encapsulated display media comprising a plurality of capsules, each capsule comprising a plurality of particles dispersed in a fluid, the display media having a first surface and a second surface;

a rear electrode disposed adjacent the second surface of the display media; and

a movable electrode, in conjunction with the rear electrode, applying an electric field across the display media.

2. The display of claim 1 wherein the movable electrode comprises a writing device.

3. The display of claim 1 further comprising a protective layer disposed adjacent the first surface.

4. The display of claim 1 wherein the encapsulated display media comprises a binder which is substantially ultraviolet light protective.

5. The display of claim 2 wherein the writing device comprises a charge generator.

6. The display of claim 5 wherein the charge generator further comprises an electronic circuit capable of increasing a voltage from about 20 V to about 1000 V.

7. The display of claim 6 wherein the charge generator further comprises an electronic circuit which reduces an applied voltage to zero after a predetermined time interval.

8. The display of claim 2 wherein the writing device comprises a charge storage device.

9. The display of claim 1 wherein the movable electrode comprises an eraser.

10. The display of claim 1 further comprising a dielectric layer disposed adjacent the first surface of the display media.

11. The display of claim 2 wherein the writing device comprises a stylus.

12. The display of claim 11 wherein the stylus comprises an electrode tip disposed within a curved end of the stylus.

13. The display of claim 1 wherein the movable electrode comprises a plurality of insulated electrodes.

14. The display of claim 11 wherein the stylus comprises a plurality of concentric electrodes.

15. The display of claim 11 wherein the stylus comprises a dielectric coating covering the electrode tip.

16. The display of claim 11 wherein the stylus comprises an elastomeric material.

17. The display of claim 1 wherein the movable electrode comprises a sliding bar, which slides across the first surface of the display media.

18. The display of claim 5 wherein the writing device includes an activator which activates the charge generator.

19. The display of claim 18 wherein the activator comprises a piezoelectric device.

20. The display of claim 17 wherein the sliding bar comprises a charge generator.

21. The display of claim 20 wherein the sliding bar comprises an activator which activates the charge generator.

22. The display of claim 1 further comprising a piezoelectric film disposed adjacent first surface of the display media.

23. The display of claim 1 wherein the movable electrode comprises a switch which reverses an electric field applied to the display media upon activation of the switch.

24. The display of claim 23 wherein a color displayed on the first surface of the display media changes upon activation of the switch.

25. The display of claim 2 wherein the writing device has a first end and a second end, wherein the display media displays a first color when the first end is disposed adjacent the first surface of the display media and a second color when the second end is disposed adjacent the first surface of the display media.

26. The display of claim 1 wherein the movable electrode comprises a stamp.

27. The display of claim 1 wherein the movable electrode comprises a user touching the first surface of the display media.

28. The display of claim 1 wherein the display media comprises a plurality of electrophoretic particles.

29. The display of claim 1 wherein the display media further comprises a top electrode disposed over a portion of the first surface of the display media.

30. The display of claim 1 wherein the display media is flexible.

31. The display of claim 1 wherein the rear electrode comprises a polymer layer and a conductive coating.

32. The display of claim 31 wherein the rear electrode is flexible.

33. The display of claim 1 wherein the movable electrode comprises an electrostatic print head.

34. The display of claim 1 wherein the rear electrode comprises a first region having a voltage different from a voltage of the movable electrode and a second region having a voltage matching the voltage of the movable electrode.

35. The display of claim 1 further comprising a casing containing a removable display media.

36. The display of claim 1 further comprising a casing containing the display media and a removable rear electrode.

37. The display of claim 1 wherein the rear electrode is disposed on a rolling belt.

38. The display of claim 1 wherein the display media is disposed on a rolling belt.

39. The display of claim 1 wherein the rear electrode comprises a conductive pattern.

40. The display of claim 1 wherein the display media comprises a plurality of electrophoretic particles comprising a plurality of colors, and wherein the rear electrode comprises a plurality of pixel electrodes, each pixel electrode being set at a voltage for displaying particles of a selected color on the first surface of the display media.

41. The display of claim 1 wherein the rear electrode is movable.

42. The display of claim 33 further comprising a speed sensor.

43. The display of claim 17 wherein the sliding bar is in communication with a data storage device.

44. The display of claim 17 wherein the sliding bar comprises a data storage device.

45. The display of claim 17 wherein the sliding bar comprises a scanner.

46. The display of claim 5 wherein the charge generator comprises one of Van de Graaff device, triboelectric mechanism, and a hand-driven electric generator.

47. The display of claim 1 further comprising a touchscreen disposed adjacent the first surface of the display media.

48. The display of claim 1 further comprising a touchscreen disposed adjacent to the rear electrode.

49. The display of claim 33 further comprising a logic circuit for driving the electrostatic print head.

50. The display of claim 1 wherein the rear electrode comprises a first region and a second region, and a voltage applied to the first region differs from a voltage applied to the second region.

51. The display of claim 2 wherein the writing device emits one of infrared, visible light, or acoustic energy.

52. The display of claim 1 further compromising a writing implement comprising a substrate, and a conductor pattern disposed on the substrate, wherein an image corresponding to the conductor pattern appears on the first surface of the display media when a moving electrode comes in contact with a portion of the conductor pattern, and the image remains on the display media upon removal of the writing implement.

53. The writing implement of claim 52 wherein the conductor pattern comprises a transparent conductor pattern.

54. The writing implement of claim 52 wherein the substrate comprises an inner edge defining a cut out portion, a portion of the inner edge being in electrical contact with the conductor pattern, such that the image corresponding to the conductor pattern appears on the first surface of the display when the writing device comes in contact with the display media through the cut out portion.

55. A display comprising:

a display media forming a continuous loop; and

an electrode disposed inside the continuous loop of the display media.

56. The display of claim 55 further comprising a casing containing the display media and the electrode, the casing having a first surface and a second surface, the first surface comprising a protective layer and serving as a writing surface.

57. The display of claim 56 further comprising a movable electrode, in conjunction with the electrode, applying an electric field across the display media.

58. The writing system of claim 55 wherein the display media comprises an encapsulated display media comprising a plurality of capsules, each capsule comprising a plurality of particles dispersed in a fluid.

59. The writing system of claim 58 wherein the plurality of particles comprises a plurality of electrophoretic particles.

60. A display comprising:

a display media having a first surface and a second surface;

an electrode disposed on the first surface of the display media; and

a photoconductor disposed on the second surface of the display media, wherein the display media displays a replica of an image shown on a substrate when the photoconductive electrode is provided adjacent the substrate.

61. The display of claim 60 wherein the substrate comprises an emissive display.

62. The display of claim 61 wherein the emissive display comprises one of a computer screen and a television screen.

63. The display of claim 60 wherein the substrate comprises a reflective display.

64. The display of claim 63 wherein the reflective display comprises a piece of paper.

65. The display of claim 60 wherein the display media comprises an encapsulated display media comprising a plurality of particles and a fluid.

66. The display of claim 65 wherein the plurality of particles comprises a plurality of electrophoretic particles.

67. The display of claim 60 further comprising a light source for illuminating the substrate.

68. A display comprising:

an encapsulated display media comprising a plurality of capsules, each capsule comprising a plurality of particles dispersed in a fluid, the display media having a first surface and a second surface;

a rear electrode disposed adjacent the second surface of the display media; and

writing device, in conjunction with the rear electrode, applying an electric field across the display media

69. A method for creating an image on a display comprising the steps of:

a) providing a display comprising an encapsulated display media comprising a plurality of capsules, each capsule comprising a plurality of particles dispersed in a fluid, the display media having a first surface and a second surface and a rear electrode disposed on the second surface of the display media;

b) placing a movable electrode adjacent the first surface of the display media; and

c) applying an electric field across the display media through the movable electrode and the rear electrode, thereby creating an image on the first surface of the display media.

70. The method of claim 69 further comprising step d) pressing a switch disposed on the movable electrode to select a line width of the image.

71. The method of claim 69 wherein step (c) compromises applying a first electric field to create an image comprising a first color and a second electric field to create an image comprising a second color.

72. The method of claim 69 wherein step (a) comprises providing a writing system comprising a display media forming a continuous loop and an electrode disposed inside the continuous loop;

and further comprising step (e) rolling the display media.

73. The method of claim 69 wherein step (c) comprises sliding an electrostatic print head across the first surface of the display media.

74. The method of claim 69 wherein step c) comprises creating an image on the writing system by drawing with a user'"'"'s hand.

75. A method for reproducing an image comprising the steps of:

a) providing a display comprising;

a1) a display media comprising a first surface and a second surface, a2) an electrode disposed on the first surface of the display media, and a3) a photoconductor disposed on the second surface of the display media; and

b) placing the photoconductor adjacent a substrate comprising an image, thereby reproducing the image from the substrate on the display media.

76. The method of claim 75 wherein step (b) comprises placing the photoconductor adjacent an emissive display.

77. The method of claim 75 wherein step (b) comprises placing the photoconductor adjacent a reflective display.