Electrochromic structures

• US 6,239,898 B1
• Filed: 11/30/1998
• Issued: 05/29/2001
• Est. Priority Date: 11/30/1998
• Status: Expired due to Term

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Roberts, John K., Cammenga, David J., Byker, Harlan J.
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): Lester, Evelyn A.
• Application Number:
  US09/200,625
• Time in Patent Office: 911 Days
• Field of Search: 359/265-275
• US Class Current: 359/265
• CPC Class Codes: G02F 1/155 Electrodes
• CPC Class Codes: G02F 1/157 Structural association of cells with optical devices, e.g. reflectors or illuminating devices

Abstract

Electrochromic windows and panels are provided which have first and second spaced elements that are optically transparent to visible light. The first and second elements each have first and second sides, and the windows and panels define a sealed chamber disposed between the second side of the first element and the first side of the second element. The sealed chamber is filled with an electrochromic medium, and the transmission of visible light through the electrochromic medium is variable when an electrical potential is applied to electrically conductive coatings that are provided on the second side of the first element and the first side of the second element. A layer partially transmissive of visible light and partially reflective of visible light is provided on one of the sides of the first or second elements so that the application of electrical potential to the electrochromic medium causes variations in the visible light transmitted through the partially visible light transmissive and partially visible light reflective layer and through the electrochromic medium whereby privacy and changes in visible color of the electrochromic medium may be either enhanced in one embodiment of the invention or hidden in another embodiment of the invention.

Claims

1. An electrochromic structure comprising, in combination, first and second spaced visible light transparent elements, one side of said first element confronting said second element including a first visible light transmissive electrically conductive layer, one side of said second element confronting said first element including a second visible light transmissive electrically conductive layer, said structure having a chamber disposed between said first and second visible light transmissive electrically conductive layers on said first and second elements, an electrochromic reversibly variable visible light transmittance medium in said chamber in contact with one of said first or second visible light transmissive electrically conductive layers, one of said first or second transparent elements having a partially visible light reflective layer thereon, wherein said partially visible light reflective layer is in contact with said electrochromic medium, and means electrically connecting both said visible light transmissive electrically conductive layers on said first and second elements to apply an electrical potential to said electrochromic medium to cause variations in the visible light transmittance of said electrochromic medium.

2. The combination as set forth in claim 1, said partially visible light reflective layer being disposed on said one side of said first transparent element confronting said second transparent element.

3. The combination as set forth in claim 1, said partially visible light reflective layer being disposed on the side of said second transparent element confronting said first transparent element.

4. The combination as set forth in claim 1, said partially visible light reflective layer comprising an alloy including palladium and silver.

5. The combination as set forth in claim 1, said visible light transmissive electrically conductive layers including fluorine doped tin oxide.

6. The combination as set forth in claim 1 wherein said electrochromic medium is gray-scale controllable over a continuous range of visible light transmittance.

7. An electrochromic window comprising, in combination, first and second spaced visible light transparent elements, said elements each having first and second surfaces, said window having a sealed chamber disposed between said second surface of said first element and said first surface of said second element, an electrochromic medium in said chamber, the transmission of visible light through said electrochromic medium being variable upon the application of an electrical potential to said medium, means for applying an electrical potential to said electrochromic medium to cause variations in the visible light transmittance of said medium, said means for applying an electrical potential to said electrochromic medium being electrically connected to electrically conductive coatings on said second surface of said first element and said first surface of said second element, and a partially visible light reflective layer disposed on one of said surfaces of said first or second elements, wherein said partially visible light reflective layer is in direct contact with said electrochromic medium, said means for applying electrical potential to said electrochromic medium being effective to cause variations in visible light transmitted through said partially visible light reflective layer and through said electrochromic medium.

8. The combination as set forth in claim 7 wherein said partially visible light reflective layer includes an alloy comprised of palladium and silver.

9. The combination as set forth in claim 7 wherein said visible light transparent electrically conductive coatings include fluorine doped tin oxide having a sheet resistance of 12-13 ohms per square.

10. An electrochromic panel comprising, in combination, first and second spaced visible light transparent elements, said elements each having first and second surfaces, said panel having a chamber disposed between said second surface of said first element and said first surface of said second element, an electrochromic medium in said chamber, the transmission of visible light through said electrochromic medium being variable upon the application of an electrical potential to said medium, means for applying an electrical potential to said electrochromic medium to cause variations in the visible light transmittance of said medium, said means for applying an electrical potential to said electrochromic medium being electrically connected to electrically conductive coatings on said second surface of said first element and said first surface of said second element, and a partially visible light reflective layer associated with one of said surfaces of said first or second elements wherein said partially visible light reflective layer is in contact with said electrochromic medium, said means for applying electrical potential to said electrochromic medium being effective to cause variations in light transmitted through said partially visible light reflective layer through said electrochromic medium.

11. The combination as set forth in claim 10 wherein said partially visible light reflective layer includes an alloy comprised of palladium and silver.

12. The combination as set forth in claim 10 wherein said visible light transparent electrically conductive coatings include fluorine doped tin oxide having a sheet resistance of 12-13 ohms per square.

13. An electrochromic structure comprising, in combination, first and second spaced visible light transparent elements, one of said elements including a partially visible light transmissive and partially visible light reflective layer, each of said elements including an electrically conductive layer, said structure having a chamber disposed between said electrically conductive layers, a self-erasing electrochromic reversibly variable visible light transmittance medium in said chamber in contact with one of said electrically conductive layers and said partially visible light transmissive and partially visible light reflective layer, and means for electrically connecting said electrically conductive layers to an electrical potential and to said electrochromic medium to cause variations in visible light transmitted through said partially visible light transmissive layer and said electrochromic medium.

14. The combination as set forth in claim 13, said partially visible light transmissive and partially visible light reflective layer being disposed on the side of said first transparent element confronting said second transparent element.

15. The combination as set forth in claim 13, said partially visible light transmissive and partially visible light reflective layer being disposed on the side of said second transparent element confronting said first transparent element.

16. The combination as set forth in claim 13, said partially visible light transmissive and partially visible light reflective layer comprising an alloy including palladium and silver.

17. The combination as set forth in claim 13, said electrically conductive layers being visible light transparent and including fluorine doped tin oxide.

18. The combination as set forth in claim 13 wherein said electrochromic medium is gray-scale controllable over a continuous range of visible light transmittance.

19. An electrochromic structure comprising, in combination, first and second spaced visible light transparent elements, one side of said first element confronting said second element including a first at least partially visible light transmissive electrically conductive layer, one side of said second element confronting said first element including a second at least partially visible light transmissive electrically conductive layer, said structure having a chamber disposed between said first and second at least partially visible light transmissive electrically conductive layers on said first and second elements, an electrochromic reversibly variable visible light transmittance medium disposed in said chamber in contact with one of said first or second at least partially visible light transmissive electrically conductive layers, one of said first or second visible light transparent elements having a partially visible light reflective layer thereon, wherein said partially visible light reflective layer is in direct contact with said electrochromic medium, both said at least partially visible light transmissive electrically conductive layers on said first and second elements being electrically connectable to a source of electrical potential so as to apply an electrical potential to said electrochromic medium to cause variations in the visible light transmittance of said electrochromic medium.

20. The combination as set forth in claim 19, said partially visible light reflective layer being disposed on said one side of said first visible light transparent element confronting said second visible light transparent element.

21. The combination as set forth in claim 19, said partially visible light reflective layer being disposed on the side of said second visible light transparent element confronting said first visible light transparent element.

22. The combination as set forth in claim 19, said partially visible light reflective layer comprising an alloy including palladium and silver.

23. The combination as set forth in claim 19, said at least partially visible light transmissive electrically conductive means including fluorine doped tin oxide.

24. The combination as set forth in claim 19 wherein said electrochromic medium is gray-scale controllable over a continuous range of visible light transmittance.

25. An electrochromic window comprising, in combination, first and second spaced visible light transparent elements, said elements each having first and second sides, said window having a chamber disposed between said second side of said first element and said first side of said second element, an electrochromic medium in said chamber, the transmission of visible light through said electrochromic medium being variable upon the application of an electrical potential to electrically conductive coatings on said second side of said first element and said first side of said second element, and a partially visible light reflective layer disposed on one of said sides of said first or second elements, wherein said partially visible light reflective layer is in direct contact with said electrochromic medium, the application of an electrical potential to said electrochromic medium being effective to cause variations in light transmitted through said partially visible light reflective layer and through said electrochromic medium.

26. The combination as set forth in claim 25 wherein said partially visible light reflective layer includes an alloy comprised of palladium and silver.

27. The combination as set forth in claim 25 wherein said visible light transparent electrically conductive coatings include fluorine doped tin oxide having a sheet resistance of 12-13 ohms per square.

28. An electrochromic panel comprising, in combination, first and second spaced visible light transparent elements, said elements each having first and second sides, said panel having a chamber disposed between said second side of said first element and said first side of said second element, an electrochromic medium in said chamber, the transmission of visible light through said electrochromic medium being variable upon the application of an electrical potential to said medium, said panel including visible light transparent electrically conductive coatings on said second side of said first element and said first side of said second element, and a partially visible light reflective layer disposed on one side of one of said first or second elements, wherein said partially visible light reflective layer is in direct contact with said electrochromic medium, the application of electrical potentials to said electrochromic medium being effective to cause variations in visible light transmitted through said partially visible light reflective layer and through said electrochromic medium.

29. The combination as set forth in claim 28 wherein said partially visible light reflective layer includes an alloy comprised of palladium and silver.

30. The combination as set forth in claim 28 wherein said visible light transparent electrically conductive coatings include fluorine doped tin oxide having a sheet resistance of 12-13 ohms per square.

31. An electrochromic structure comprising, in combination, first and second spaced visible light transparent elements, one of said elements including a partially visible light transmissive and partially visible light reflective layer, wherein said partially visible light transmissive and partially visible light reflective layer is in contact with a self-erasing electrochromic reversibly variable visible light transmittance medium, each of said elements including electrically conductive layers, said structure having a chamber disposed between said electrically conductive layers, a self-erasing electrochromic reversibly variable visible light transmittance medium in said chamber in contact with one of said electrically conductive layers, the application of electrical potential to said electrically conductive layers effecting the application of an electrical potential to said electrochromic medium to cause variations in visible light transmitted through said partially visible light transmissive and partially visible light reflective layer.

32. The combination as set forth in claim 31, said partially visible light transmissive and partially visible light reflective layer being disposed on the side of said first visible light transparent element confronting said second visible light transparent element.

33. The combination as set forth in claim 31, said partially visible light transmissive and partially visible light reflective layer being disposed on the side of said second visible light transparent element confronting said first visible light transparent element.

34. The combination as set forth in claim 31, said partially visible light transmissive and partially visible light reflective layer comprising an alloy including palladium and silver.

35. The combination as set forth in claim 31, said electrically conductive layers including fluorine doped tin oxide.

36. The combination as set forth in claim 31 wherein said electrochromic medium is gray-scale controllable over a continuous range of visible light transmittance.