Thin-film coatings, electro-optic elements and assemblies incorporating these elements

• US 7,688,495 B2
• Filed: 03/05/2007
• Issued: 03/30/2010
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Brummel, Nelson F., Neuman, George A., Cammenga, David J., Tonar, William L., Anderson, John S., Luten, Henry A., Dozeman, Gary J., Forgette, Jeffrey A., Perron, Lansen M., Poe, G. Bruce
• Primary Examiner(s): Thompson; Timothy J
• Application Number:
  US11/713,849
• Publication Number:
  US 20080030836A1
• Time in Patent Office: 1,121 Days
• Field of Search: 359/265, 359/267, 359/270, 359/273, 359/274, 359/266, 359/272
• US Class Current: 359/265
• CPC Class Codes: B60R 1/084 using a removable filtering or hiding screen associated with windows or windscreens B60J3/00
• 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

Electro-optic elements are becoming commonplace in a number of vehicular and architectural applications. Various electro-optic element configurations provide variable transmittance and or variable reflectance for windows and mirrors. The present invention relates to various thin-film coatings, electro-optic elements and assemblies incorporating these elements.

Claims

1. An electro-optic element configured for use in a rearview automotive mirror, the electro-optic element comprising:

a first substrate including first and second surfaces, the first substrate containing at least a first layer of electrically conductive material deposited on the second surface; and

a second substrate including third and forth surfaces, the first and second substrates disposed in a parallel and spaced-apart relationship to define a gap between the second and third surfaces, the gap containing an electro-optic medium, the second substrate containing a thin-film coating that includes at least a second layer of electrically conductive material deposited on the third surface,

wherein at least one of the first and second layers is characterized by a mean peak-to-valley surface roughness less than or equal to approximately 150 Å

.

2. An electro-optic element as in claim 1 wherein said mean peak-to-valley surface roughness is less than or equal to about 100 Å

.

3. An electro-optic element as in claim 1 wherein said mean peak-to-valley surface roughness is less than or equal to about 50 Å

.

4. An electro-optic element as in claim 1 wherein said mean peak-to-valley surface roughness is less than or equal to about 25 Å

.

6. An electro-optic element as in claim 1, wherein the at least a first layer of electrically conductive material includes a layer of indium-tin-oxide having an effective optical thickness of approximately one half-wave.

12. An electro-optic element as in claim 1 characterized by a variable transmittance.

13. An electro-optic element as in claim 1 characterized by a variable reflectance.

5. An electro-optic element as in claim l, wherein the at least second layer of material includes a layer of indium-tin-oxide having an optical thickness of at least approximately one quarter-wave.

7. An electro-optic element as in claim l, wherein at least one of the first and second layers of material is characterized by a bulk resistance less than 200 μ

ohm-cm.

8. An electro-optic element as in claim l, wherein the at least second layer of material includes a layer of chrome.

9. An electro-optic element as in claim 8, wherein the thin-film coating is characterized by a sheet resistance of no greater than 6 Ohm per square.

10. An electro-optic element as in claim 8, wherein the sheet resistance of the thin-film coating is no greater than 2 Ohm per square.

11. An electro-optic element as in claim 8, wherein said layer of chrome has a reflectance of at least approximately 80% of a theoretical maximum.

14. An electro-optic element configured for use in a rearview automotive mirror, the electro-optic element comprising:

a first substrate including first and second surfaces, the first substrate containing a thin-film coating that includes at least one layer of electrically conductive material deposited on at least one of the surfaces, wherein the at least one layer of electrically conductive material is characterized by a mean peak-to-valley surface roughness less than or equal to approximately 150 Å

.

15. An electro-optic element as in claim 14 wherein said mean peak-to-valley surface roughness is less than or equal to about 100 Å

.

16. An electro-optic element as in claim 14 wherein said mean peak-to-valley surface roughness is less than or equal to about 50 Å

.

17. An electro-optic element as in claim 14 wherein said mean peak-to-valley surface roughness is less than or equal to about 25 Å

.

18. An electro-optic element as in claim 14, wherein the at least one layer of material includes a layer of indium-tin-oxide.

19. An electro-optic element as in claim 18, wherein an optical thickness of said indium-tin-oxide layer is at least approximately one quarter-wave.

20. An electro-optic element as in claim 18, wherein an optical thickness of the indium-tin-oxide layer is at least approximately one half-wave.

21. An electro-optic element as in claim 14, wherein the at least one layer of material is characterized by a bulk resistance less than 200 μ

ohm-cm.

22. An electro-optic element as in claim 14, wherein the at least one layer of material includes a layer of chrome.

23. An electro-optic element as in claim 22 wherein a thickness of said layer of chrome is at least approximately 250 Å

and wherein said layer of chrome has a reflectance of at least approximately 80 percent of a theoretical maximum.

24. An electro-optic element as in claim 22, wherein the thin-film coating is characterized by a sheet resistance of about 1.5 Ohm per square.

25. An electro-optic element as in claim 14 characterized by a variable transmittance.

26. An electro-optic element as in claim 14 characterized by a variable reflectance.

27. An electro-optic element as in claim 14, further comprising a second substrate comprising third and fourth surfaces, said second substrate comprising at least one layer of material on at least one of said third and fourth surfaces comprising a mean peak-to-valley surface roughness less than or equal to approximately 150 Å

.

28. An electro-optic element configured for use in a rearview automotive mirror, the electro-optic element comprising:

a first substrate including first and second surfaces, the first substrate including at least one layer of indium-tin-oxide deposited on the second surface, the at least one layer of indium-tin-oxide having a mean peak-to-valley surface roughness less than or equal to approximately 150 Å

; and

a second substrate including third and fourth surfaces, the first and second substrate disposed in a parallel and spaced-apart relationship to define a gap between the second and third surfaces, the gap containing an electro-optic medium, the second substrate containing a thin-film coating that includes at least one layer of chrome on the third surface, the at least one layer of chrome having a mean peak-to-valley surface roughness less than or equal to approximately 150 Å

.

29. An electro-optic element as in claim 28, wherein an optical thickness of the indium-tin-oxide layer is at least approximately one quarter-wave.

30. An electro-optic element as in claim 28, wherein an optical thickness of the indium-tin-oxide layer is at least approximately one half-wave.

31. An electro-optic element as in claim 28, wherein the optical thickness of the indium-tin-oxide layer thickness is at least approximately 80% of one half-wave.

32. An electro-optic element as in claim 28, wherein the indium-tin-oxide layer is characterized by a bulk resistance less than 200 μ

ohm-cm.

33. An electro-optic element as in claim 28, wherein a thickness of said layer of chrome is at least approximately 250 Å

and wherein said layer of chrome has a reflectance of at least 80 percent of a theoretical maximum.

34. An electro-optic element as in claim 28, wherein the sheet resistance of the thin-film coating is no greater than 2 Ohm per square.

35. An electro-optic element as in claim 28 characterized by a variable reflectance.

36. An electro-optic element as in claim 28 further comprising a second layer of chrome deposited in a periphery area of the second surface.

37. An electro-optic element as in claim 36, wherein a b* value associated with the periphery area of the second surface substantially matches a b* value associated with the thin-film coating.

38. An electro-optic element configured for use in a rearview automotive mirror, the electro-optic element comprising:

a first substrate including first and second surfaces, the first substrate having a first layer of indium-tin-oxide on the second surface, the layer of indium-tin-oxide having a mean peak-to-valley surface roughness less than or equal to approximately 150 Å

; and

a second substrate including third and fourth surfaces, the first and second substrates disposed in a parallel and spaced-apart relationships to define a gap between the second and third surfaces, the gap containing an electro-optic medium, the second substrate containing a second layer of indium-tin-oxide deposited on the third surface, the second layer of indium-tin-oxide having a mean peak-to-valley surface roughness less than or equal to approximately 150 Å

.

39. An electro-optic element as in claim 38, wherein thicknesses of the first and second indium-tin-oxide layers are at least approximately one half-wave.

40. An electro-optic element as in claim 38, wherein the first and second indium-tin-oxide layers are characterized by a bulk resistance less than 200 μ

ohm-cm.

41. An electro-optic element as in claim 38 characterized by a variable transmittance.