Electrochromic, electroluminescent and electrochemiluminescent displays

• US 5,189,549 A
• Filed: 02/26/1990
• Issued: 02/23/1993
• Est. Priority Date: 02/26/1990
• Status: Expired due to Term

• Current Assignee: BioVeris Corporation (Roche Holding AG)
• Original Assignee: Molecular Displays, Inc.
• Inventors: Leventis, Nicholas, Wrighton, Mark S.
• Primary Examiner(s): Hille, Rolf
• Assistant Examiner(s): Limanek, Robert
• Application Number:
  US07/485,379
• Time in Patent Office: 1,093 Days
• Field of Search: 350/357, 359/271, 359/268
• US Class Current: 359/271
• CPC Class Codes: F21K 2/08 activated by an electric field, i.e. electrochemiluminescence
• CPC Class Codes: G02F 1/15 based on an electrochromic effect
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions
• CPC Class Codes: G02F 1/1523 comprising inorganic material
• CPC Class Codes: G02F 1/1525 characterised by a particular ion transporting layer, e.g. electrolyte
• CPC Class Codes: G02F 1/155 Electrodes
• CPC Class Codes: G02F 2001/1517 Cyano complex compounds, e.g. Prussian blue
• CPC Class Codes: G02F 2001/1555 Counter electrode
• CPC Class Codes: G02F 2001/1557 Side by side arrangements of working and counter electrodes

Abstract

A display having an array of matrix addressable pairs of electrodes mounted face up on the same substrate. The pairs of electrodes are derivatized with either electrochromic materials or electroluminescent material to form the pixels of the display. In the electrochromic embodiment of the invention, a layer of a solid polymer electrolyte is included. The air of electrodes may also be left clean of derivatizing material, but with an electroluminescent substance dissolved in the solid polymer electrolyte. An electrochemiluminescent embodiment is also provided where the electrochemiluminescent substance can be dissolved in the solid polymer electrolyte. A method of patterning the electrolyte layer to form relatively non-conductive borders around each of the pairs by selective exposure of the electrolyte layer in the region of the border to electromagnetic radiation to cause permanent change in the chemical composition of the electrolyte so that the exposed border regions are rendered relatively non-conductive is also provided. An electrically reconfigurable photomask having an area comprised of an arrangement of electrochromic covered electrode pairs constituting pixels, the opacity and transmissivity of which may be controlled by application of an electrical bias to yield complete control over the transmissivity and opacity of each pixel of the areas, is also provided.

Claims

1. An electrochromic display pixel comprising a substrate, a pair of electrodes mounted face up and side by side on one side of said substrate and in close proximity to each other, at least one of said electrodes being coated on its face with a first chemical substance which is electrochromic, a layer of ionically conductive electrolyte over said electrode pair to complete an electrochemical cell so that when a bias is imposed between the electrodes of said pair, said first chemical substance changes its spectral absorption characteristics, a relatively non-conductive border region surrounding said pixel, and a transparent cover having a substantially non-conductive face in contact with said electrolyte layer.

2. The display pixel defined in claim 1, wherein said first chemical substance material is confined on one of said electrodes and the other electrode of said pair is coated with a second chemical substance which is electrochemically complementary to said first chemical substance.

3. The display pixel defined in claim 2, wherein said second chemical substance is electrochromically complementary to said first chemical substance.

4. The display pixel defined in claim 3, wherein said first chemical substance is tungsten trioxide and said second chemical substance is polyaniline.

5. The display pixel defined in claim 3, wherein said first chemical substance is tungsten trioxide and said second chemical substance is a poly 3-methythiophene.

6. The display pixel defined in claim 3, wherein said first chemical substance is viologen and said second chemical substance is polyvinylferrocene.

7. The display pixel defined in claim 3, wherein said first chemical substance is tungsten trioxide and said second chemical substance is anodically grown iridium oxide.

8. The display pixel defined in claim 1, wherein said electrolyte is a solid electrolyte.

9. The display pixel defined in claim 8, wherein said solid electrolyte is a polymer.

10. The display pixel defined in claim 1, wherein said electrodes of said pair interdigitate with each other.

11. The display pixel defined in claim 1, wherein said pixel is less than about 200 microns across.

12. The display pixel defined in claim 1, wherein at least one of said electrodes is at least partially embedded into the one side of said substrate.

13. The display pixel as defined in claim 1, wherein at least one of said electrodes is transparent.

14. The display pixel defined in claim 1, wherein said border region around said pixel is comprised of said electrolyte layer rendered relatively non-conductive in place by selective exposure of said border region to electromagnetic radiation.

15. The display pixel defined in claim 14, wherein said relatively non-conductive border region surrounding said pixel includes a polymer formed by subjecting a monomer or oligomer mixed in the electrolyte to electromagnetic radiation to reduce the mobility of charge carriers in the border region of said electrolyte.

16. The display pixel defined in claim 14, wherein said relatively non-conductive border region surrounding said pixel includes a polymer formed by exposing a monomer or oligomer previously mixed in the electrolyte to electromagnetic radiation to induce cross-linking of said monomer or oligomer with said electrolyte of said border region to reduce the mobility of charge carriers in the border region of said electrolyte.

17. The display pixel defined in claim 1, wherein said electrolyte includes a metal complex that can photorelease a substance that reduces the mobility of the current supporting ions upon exposure to UV-light.

18. The display pixel defined in claim 1, wherein said electrolyte includes a substance which can release a base upon exposure to UV-light to neutralize the protons that are responsible for charge transport in the electrolyte.

19. A display comprising an array of matrix addressable pairs of electrodes, said array comprising:

(a) a substrate;

(b) a plurality of substantially parallel and spaced apart electronically conductive means defining columns of bus bars mounted on one side of said substrate, each of said column bus bars being electrically separate from the other column bus bars so that each is independently addressable by electrical biasing means;

(c) a plurality of column electrode means mounted face up on said one side of said substrate and spaced at intervals along each of said column bus bars;

(d) a plurality of substantially parallel and spaced apart electronically conductive means defining row bus bars on said one side of said substrate, said row bus bars crossing but being electrically insulated from said column bus bars, each of said row bus bars being electrically separate from the other row bus bars so that each of said row bus bars is independently addressable by electrical biasing means;

(e) a plurality of row electrode means mounted face up on said one side of said substrate and spaced at intervals along each row bus bar, each of said row electrodes being positioned to have a column electrode in close proximity to and side by side therewith to define an electrode pair; and

(f) a transparent cover having a substantially non-conductive face in contact with said electrolyte layer.

20. The display defined in claim 19, wherein the row electrode of each pair interdigitates with its associated column electrode.

21. The display defined in claim 19, wherein each said electrode pair is less than about 200 microns across.

22. The display defined in claim 19, further including a coating of a first chemical substance which is electrochromic on the face at least one of said electrodes of each of said pairs and a layer of ionically conductive electrolyte over said pairs of electrodes.

23. The display defined in claim 22, wherein said electrochromic first chemical substance is confined on the face of one of the electrodes of each pair and the other electrode of said pair is coated on its face with a second chemical substance which is electrochemically complementary to said first chemical substance.

24. The display defined in claim 23, wherein said second chemical substance is further electrochromically complementary to said first chemical substance.

25. The display defined in claim 24, wherein said electrochromic first chemical substance is tungsten trioxide and said electrochromic second chemical substance is polyaniline.

26. The display defined in claim 24, wherein said electrochromic first chemical substance is tungsten trioxide and said electrochromic second chemical substance is poly 3-methythiophene.

27. The display defined in claim 24, wherein said electrochromic first chemical substance is viologen and said electrochromic second chemical substance is polyvinylferrocene.

28. The display defined in claim 24, wherein said electrochromic first chemical substance is tungsten trioxide and said electrochromic second chemical substance is anodically grown iridium oxide.

29. The display defined in claim 22, wherein said electrolyte is substantially solid.

30. The display as defined in claim 29, wherein said solid electrolyte is a polymer.

31. The display defined in claim 22, wherein said layer of electrolyte is separated into individual zones over each of said pairs by relatively non-conducting borders so that each electrode pair constitutes a substantially separate electrochemical cell.

32. The display defined in claim 22, wherein said relatively non-conductive borders around each of said pairs are comprised of said electrolyte layer rendered relatively non-conductive in place by selective exposure of said electrolyte layer in the region of said border to electromagnetic radiation.

33. The display defined in claim 32, wherein said relatively non-conductive borders surrounding each of said pairs includes a polymer formed by subjecting a monomer or oligomer previously mixed in the electrolyte to electromagnetic radiation to reduce the mobility of charge carriers in the border region of said electrolyte.

34. The display defined in claim 32, wherein said relatively non-conductive borders include a polymer formed by subjecting a monomer or oligomer to electromagnetic radiation to induce cross-linking of said monomer or oligomer with said electrolyte to reduce the mobility of charge carriers in the border region of said electrolyte.

35. The display defined in claim 22, wherein said electrolyte includes a metal complex that can photorelease a substance that reduces the mobility of the current supporting ions upon exposure to UV-light.

36. The display defined in claim 32, wherein said electrolyte includes a substance which can release a base upon exposure to UV-light to neutralize the protons that are responsible for charge transport in the electrolyte.

37. The display as defined in claim 19, wherein at least some of said column bus bars are at least partially embedded into the one side of said substrate.

38. The display as defined in claim 19, wherein at least some of said electrode means are at least partially embedded into the one side of said substrate.

39. The display as defined in claim 19, wherein at least some of said electrode means are transparent.

40. A display pixel comprising a pair of first and second electrodes having faces in opposed and spaced apart relationship to each other, said first electrode including on its opposed face a coating of a first chemical substance which is electrochromic, said second electrode including on its opposed face a coating of a second chemical substance electrochemically complementary to said first chemical substance, a layer of electrolyte sandwiched between said coated first and second electrodes so that when a bias is imposed between said electrodes, said electrochromic first chemical substance changes its spectral absorption characteristics and a relatively non-conductive border region surrounding said pixel, said electrolyte including a metal complex that can photorelease a substance that reduces the mobility of the current supporting ions upon exposure to UV-light and said border region around said pixel being comprised of said electrolyte layer rendered relatively non-conductive in place by photorelease of said substance caused by selective exposure of said border region to UV-light.

42. The display pixel as defined in claim 40, wherein said electrochromic first substance is tungsten trioxide and said electrochromic second substance is polyaniline.

43. The display pixel as defined in claim 40, wherein said electrochromic first substance is tungsten trioxide and said electrochromic second substance is poly 3-methylthiophene.

44. The display pixel as defined in claim 40, wherein said electrochromic first substance is viologen and said electrochromic second substance is polyvinylferrocene.

45. The display pixel as defined in claim 40, wherein said electrochromic first substance is tungsten trioxide and said electrochromic second substance is anodically grown iridium oxide.

46. The display pixel defined in claim 40, wherein said electrolyte is substantially solid.

47. The display pixel defined in claim 46, wherein said solid electrolyte is a polymer.

48. The display pixel defined in claim 40, wherein said pixel is less than about 200 microns across.

41. A display pixel comprising a first electrode and a second electrode in opposed and spaced apart relationship to each other, said first electrode including on its opposed face a coating of a first chemical substance which is electrochromic, a layer of electrolyte covering and electrolytically connecting said coated first and second electrodes, said electrolyte including a substance that can release a base upon exposure to UV-light to neutralize the protons that are responsible for charge transport in the electrolyte thereby rendering the exposed electrolyte relatively non-conductive, said electrolyte layer including a border region surrounding said pixel rendered relatively non-conductive by release of said base and having a central region substantially free of said released base.

49. A display comprising an array of matrix addressable pixels, said display comprising:

(a) a first substrate;

(b) a plurality of substantially parallel and spaced apart means defining columns of bus bars mounted on said first substrate, each of said column bus bars being independently addressable by electrical biasing means and having a plurality of column electrode means face up and at spaced intervals along the length of said column;

(c) a second substrate in opposed and facing relationship to said first substrate but spaced apart therefrom,

(d) a plurality of substantially parallel and spaced apart means defining rows of bus bars mounted face up on said second substrate, each of said row bus bars being independently addressable by electrical biasing means and having a plurality of row electrode means at spaced intervals along its length so that each row electrode is in opposed and facing relationship to a corresponding column electrode means but spaced apart therefrom to define an electrode pair;

(e) a coating of a first electrochromic material on the face of each of said column electrode means and a coating of a material electrochemically complementary to said first electrochromic material on each of said row electrode means;

(f) a layer of electrolyte sandwiched between each said first and second electrodes, said electrolyte including a metal complex that can photorelease a substance that reduces the mobility of the current supporting ions upon exposure to UV-light, said layer of electrolyte being separated into individual zones by relatively non-conducting borders comprised of said electrolyte rendered relatively non-conducting by photorelease of said substance caused by selective exposure to UV light so that each electrode pair constitutes a substantially separate electrochemical cell defining a pixel.

50. The display as defined in claim 49, wherein said first electrochromic material is tungsten trioxide and said second electrochromic material is polyaniline.

51. The display as defined in claim 49, wherein said first electrochromic material is tungsten trioxide and said second electrochromic material is poly 3-methylthiophene.

52. The display as defined in claim 49, wherein said first electrochromic material is viologen and said second electrochromic material is polyvinylferrocene.

53. The display as defined in claim 49, wherein said first electrochromic material is tungsten trioxide and said second electrochromic material is anodically grown iridium oxide.

54. The display defined in claim 49, wherein said electrolyte is substantially solid.

55. The display defined in claim 54, wherein said solid electrolyte is a polymer.

56. The display defined in claim 49, wherein each of said pairs is less than about 200 microns across.

57. A multilayer laminated display comprising at least first and second matrix addressable arrays of pixels, each of said arrays comprising:

(a) a substrate;

(b) a plurality of substantially parallel and spaced apart electronically conductive means defining columns of bus bars mounted on one side of said substrate, each of said column bus bars being electrically separate from the other column bus bars so that each is independently addressable by electrical biasing means;

(c) a plurality of column electrode means mounted face up on said one side of said substrate and spaced at intervals along each of said column bus bars;

(d) a plurality of substantially parallel and spaced apart electronically conductive means defining row bus bars on said one side of said substrate, said row bus bars crossing but being electrically insulated from said column bus bars, each of said row bus bars being electrically separate from the other row bus bars so that each of said row bus bars is independently addressable by electrical biasing means;

(e) a plurality of row electrode means mounted face up on said one side of said substrate and spaced at intervals along each row bus bar, each of said row electrodes being positioned to have a column electrode in close proximity thereto and side by side therewith to define an electrode pair, at least one of said electrodes of each said pair being coated on its face with a first electrochromic material; and

(f) a layer of ionically conductive electrolyte over said pairs of electrodes, to complete an electrochemical cell, said layer of electrolyte being separated by relatively non-conductive border regions into a plurality of zones, each of said zones being associated with one of said pair of electrodes.

58. A multilayer laminated display comprising first and second matrix addressable arrays of pixels, each of said arrays comprising:

(a) a first substrate;

(b) a plurality of substantially parallel and spaced apart electronically conductive means defining columns of bus bars mounted on said first substrate, each of said column bus bars being independently addressable by electrical biasing means and having a plurality of transparent column electrode means mounted face up and at spaced intervals along the length of said column, each of said column electrode means being coated on its face with a first electrochromic material;

(c) a second substrate in opposed and facing relationship to said first substrate but spaced apart therefrom,

(d) a plurality of substantially parallel and spaced apart electronically conductive means defining rows of bus bars mounted face up on said second substrate, each of said row bus bars being independently addressable by electrical biasing means and having a plurality of transparent row electrode means mounted face up and at spaced intervals along the length of said row so that each row electrode is in opposed and facing relationship to a corresponding column electrode means but spaced apart therefrom to define a display pixel, each of said row electrode means being coated on its face with a material electrochemically complementary to said first electrochromic material;

(e) a layer of electrolyte sandwiched between said coated first and second electrodes and a relatively non-conductive border separating said layer of electrolyte into substantially separate zones, each of zones being associated with one of said pixels.

59. The multilayer laminated display defined in claim 58, wherein said electrochemically complementary material is a second electrochromic material electrochromically complementary to said first electrochromic material.

60. The multilayer laminated display defined in claim 58, wherein the pixels of respective ones of said arrays are fully offset from one another.

61. The multilayer laminated display defined in claim 58, wherein the pixels of respective ones of said arrays are partially offset from one another.

62. The multilayer laminated display defined in claim 59, wherein said first electrochromic material of said first array is electrically changable between color states and said first electrochromic material of said second array is changable between color states different from the color states of said first electrochromic material of said first array.

63. The multilayer laminated display defined in claim 58, wherein there are at least three layers of said arrays.