EXTERIOR REARVIEW MIRROR ASSEMBLY

• US 20130107563A1
• Filed: 12/17/2012
• Published: 05/02/2013
• Est. Priority Date: 09/20/2002
• Status: Active Grant

• Current Assignee: Donnelly Corporation (Magna International Incorporated)
• Original Assignee: Donnelly Corporation (Magna International Incorporated)
• Inventors: McCabe, Ian A., Varaprasad, Desaraju V., Habibi, Hamid, Lynam, Niall R.
• Granted Patent: US 8,797,627 B2
• Time in Patent Office: Days
• US Class Current: 362/540
• CPC Class Codes: B60Q 1/2665 on rear-view mirrors lighting devices for vehicle interior on or for rear-view mirrors B60Q3/258
• CPC Class Codes: B60Q 1/34 for indicating change of drive direction B60Q1/22 takes precedence
• CPC Class Codes: B60Q 2400/40 Welcome lights, i.e. specific or existing exterior lamps to assist leaving or approaching the vehicle
• CPC Class Codes: B60R 1/04 mounted inside vehicle B60R1/025, B60R1/08 take precedence
• CPC Class Codes: B60R 1/06 mounted on vehicle exterior B60R1/025, B60R1/08 take precedence
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: B60R 1/1207 with lamps; with turn indicators
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 5/0875 the reflecting layers comprising two or more metallic layers
• CPC Class Codes: G02B 5/10 with curved faces
• 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
• CPC Class Codes: G02F 1/161 Gaskets; Spacers; Sealing of cells; Filling or closing of cells
• CPC Class Codes: G02F 1/163 Operation of electrochromic cells, e.g. electrodeposition cells; Circuit arrangements therefor

Abstract

An exterior rearview mirror assembly includes a variable reflectance mirror reflective element. A mirror reflector of the mirror reflective element includes a stack of thin films having at least two thin films. At least one of the thin films is formed of a material that has a specific resistivity of less than about 1×10⁻² ohm·cm, and at least one of the thin films is a thin metal film. An electrochromic medium is disposed in an interpane cavity of the mirror reflective element and is bounded by a perimeter seal. A reflective perimeter layer is disposed at a second surface of a front substrate proximate a perimeter edge of the front substrate. The perimeter layer generally conceals the perimeter seal from view by a driver of the vehicle normally viewing the front substrate when the exterior rearview mirror assembly is mounted at the vehicle.

Claims

1. An exterior rearview mirror assembly suitable for use for a vehicle, said exterior rearview mirror assembly comprising:

a casing portion;

wherein said casing portion comprises a variable reflectance mirror reflective element;

an attachment portion;

wherein said attachment portion is configured for attaching at a side of a vehicle;

wherein said mirror reflective element comprises a front substrate and a rear substrate and an electrochromic medium disposed between said front and rear substrates;

wherein said front substrate has a first surface and a second surface and wherein a transparent electrically conductive layer is disposed at said second surface of said front substrate;

wherein said rear substrate has a third surface and a fourth surface and wherein a mirror reflector is disposed at at least a portion of said third surface of said rear substrate;

wherein said mirror reflector comprises a stack of thin films and wherein said stack of thin films comprises at least two thin films;

wherein at least one of said thin films is formed of a material that has a specific resistivity of less than about 1×

10<sup>−

2</sup> ohm·

cm;

wherein at least one of said thin films comprises a thin metal film;

wherein said electrochromic medium is disposed in an interpane cavity between said third surface of said rear substrate and said second surface of said front substrate and is bounded by a perimeter seal;

wherein no part of said rear substrate extends beyond any part of said front substrate;

wherein a perimeter layer is disposed at said second surface of said front substrate proximate a perimeter edge of said front substrate, and wherein said perimeter layer comprises a reflective perimeter layer;

wherein said perimeter layer comprises at least one thin metal film and wherein said perimeter layer is electrically conductive;

wherein said perimeter layer generally conceals said perimeter seal from view by a driver of the vehicle normally viewing said front substrate when said exterior rearview mirror assembly is mounted at the vehicle; and

wherein said exterior rearview mirror assembly comprises a light source and wherein said light source is at least one of (i) disposed rearward of said mirror reflective element and, when actuated, illuminates through said mirror reflective element, (ii) disposed at said casing portion and (iii) disposed at said attachment portion.

2. The exterior rearview mirror assembly of claim 1, wherein said light source is disposed at said casing portion.

3. The exterior rearview mirror assembly of claim 2, wherein said light source comprises a light source of a ground illumination light that, when said light source is actuated, illuminates a ground area generally at the side of the vehicle at which said attachment element is attached when said exterior rearview mirror assembly is mounted at the vehicle.

4. The exterior rearview mirror assembly of claim 1, wherein said light source is disposed rearward of said mirror reflective element and, when actuated, illuminates through said mirror reflective element.

5. The exterior rearview mirror assembly of claim 4, wherein said light source, when actuated, illuminates through said mirror reflector of said mirror reflective element.

6. The exterior rearview mirror assembly of claim 4, wherein said light source comprises a light source of an indicator.

7. The exterior rearview mirror assembly of claim 6, wherein said indicator, at least when said light source is actuated, is viewable by a driver of the vehicle normally viewing said front substrate when said exterior rearview mirror assembly is mounted at the vehicle.

8. The exterior rearview mirror assembly of claim 6, wherein said indicator comprises a turn signal indicator.

9. The exterior rearview mirror assembly of claim 1, wherein said light source is disposed at said attachment portion.

10. The exterior rearview mirror assembly of claim 9, wherein said light source comprises a light source of a ground illumination light that, when said light source is actuated, illuminates a ground area generally at the side of the vehicle at which said attachment element is attached when said exterior rearview mirror assembly is mounted at the vehicle.

11. The exterior rearview mirror assembly of claim 1, wherein said light source comprises at least one light emitting diode.

12. The exterior rearview mirror assembly of claim 1, wherein said casing portion is movable relative to said attachment portion.

13. The exterior rearview mirror assembly of claim 1, wherein said mirror reflective element is movable relative to said casing portion.

14. The exterior rearview mirror assembly of claim 13, wherein said light source is disposed rearward of said mirror reflective element and, when actuated, illuminates through said mirror reflective element.

15. The exterior rearview mirror assembly of claim 1, wherein said material of said at least one of said thin films has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm.

16. The exterior rearview mirror assembly of claim 15, wherein said material is a metal, and wherein said thin metal film of said at least two thin films of said stack of thin films is formed of said metal.

17. The exterior rearview mirror assembly of claim 16, wherein said metal has a specific resistivity of less than about 5×

10<sup>−

4</sup> ohm·

cm.

18. The exterior rearview mirror assembly of claim 17, wherein said metal has a specific resistivity of less than about 5×

10<sup>−

5</sup> ohm·

cm.

19. The exterior rearview mirror assembly of claim 16, wherein another of said at least two thin films of said stack of films comprises another thin metal film, and wherein said another thin metal film is formed of a metal that has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm.

20. The exterior rearview mirror assembly of claim 19, wherein said metal of said thin metal film is different from said metal of said another thin metal film.

21. The exterior rearview mirror assembly of claim 1, wherein at least one of (i) said front substrate has a thickness of about 0.063 inches or less, (ii) said rear substrate has a thickness of about 0.063 inches or less, (iii) said front substrate has a thickness of about 0.063 inches or less and said rear substrate has a thickness of about 0.063 inches or less, (iv) at least one of said front substrate and said rear substrate has a thickness of about 0.043 inches or less, and (v) one of said front substrate and said rear substrate has a thickness of about 0.063 inches or less and the other of said front substrate and said rear substrate has a thickness of about 0.043 inches or less.

22. The exterior rearview mirror assembly of claim 1, wherein said mirror reflector has a sheet resistance of less than about 5 ohms per square.

23. The exterior rearview mirror assembly of claim 1, wherein said exterior rearview mirror assembly comprises a driver-side exterior rearview mirror assembly.

24. The exterior rearview mirror assembly of claim 23, wherein said perimeter seal is at least partially visible to a person viewing through said rear substrate.

25. The exterior rearview mirror assembly of claim 1, wherein said stack of thin films comprises a spectrally-selective transflective stack of thin films having a multi-band transmission spectrum.

26. The exterior rearview mirror assembly of claim 1, wherein at least one thin film of said stack of thin films extends beyond said perimeter seal towards said perimeter edge of said rear substrate.

27. The exterior rearview mirror assembly of claim 1, wherein at least one of (i) one of said thin films has a thickness of at least about 600 angstroms and (ii) said mirror reflector provides at least about 55 percent photopic reflectance measured in accordance with Society of Automotive Engineers test procedure SAE J964a.

28. The exterior rearview mirror assembly of claim 1, wherein said at least one thin metal film of said perimeter layer comprises chromium.

29. The exterior rearview mirror assembly of claim 1, wherein said front and rear substrates comprise curved substrates.

30. The exterior rearview mirror assembly of claim 29, wherein said mirror reflective element comprises a curved mirror reflective element having a more curved outboard region and a less curved inboard region.

31. The exterior rearview mirror assembly of claim 30, wherein said front and rear substrates comprise aspheric substrates.

32. The exterior rearview mirror assembly of claim 31, comprising a demarcation that demarcates said more curved outboard region of said mirror reflective element from said less curved inboard region of said mirror reflective element.

33. The exterior rearview mirror assembly of claim 32, wherein said demarcation comprises one of (i) a continuous line and (ii) closely interspaced dots, dashes and spots.

34. The exterior rearview mirror assembly of claim 1, wherein said perimeter seal is at least partially visible to a person viewing through said rear substrate.

35. The exterior rearview mirror assembly of claim 1, wherein light that reflects off of said mirror reflector and passes through said electrochromic medium and said front substrate has a substantially untinted reflectant characteristic to a person normally viewing said front substrate of said mirror reflective element when no voltage is applied to said electrochromic medium.

36. The exterior rearview mirror assembly of claim 1, wherein an electrically conductive tab portion, which is in electrically conductive contact with said mirror reflector, extends from under said perimeter seal outward towards a portion of said perimeter edge of said rear substrate, and wherein said electrically conductive tab portion at least partially wraps around the edge dimension between said third surface and said fourth surface of said rear substrate at said portion of said perimeter edge of said rear substrate, and wherein an electrical connection is made at said electrically conductive tab portion, and wherein said portion of said perimeter edge of said rear substrate is inward of a corresponding perimeter edge portion of said front substrate.

37. An exterior rearview mirror assembly suitable for use for a vehicle, said exterior rearview mirror assembly comprising:

a casing portion;

wherein said casing portion comprises a variable reflectance mirror reflective element;

an attachment portion;

wherein said attachment portion is configured for attaching at a side of a vehicle;

wherein said mirror reflective element comprises a front substrate and a rear substrate and an electrochromic medium disposed between said front and rear substrates;

wherein said front substrate has a first surface and a second surface and wherein a transparent electrically conductive layer is disposed at said second surface of said front substrate;

wherein said rear substrate has a third surface and a fourth surface and wherein a mirror reflector is disposed at at least a portion of a surface of said rear substrate;

wherein said mirror reflector comprises a stack of thin films and wherein said stack of thin films comprises at least a first thin film and a second thin film;

wherein said first thin film is formed of a material that has a specific resistivity of less than about 1×

10<sup>−

2</sup> ohm·

cm;

wherein said second thin film is formed of a material that has a specific resistivity of less than about 1×

10<sup>−

2</sup> ohm·

cm;

wherein said electrochromic medium is disposed in an interpane cavity between said third surface of said rear substrate and said second surface of said front substrate and is bounded by a perimeter seal;

wherein no part of said rear substrate extends beyond any part of said front substrate;

wherein a perimeter layer is disposed at said second surface of said front substrate proximate a perimeter edge of said front substrate, and wherein said perimeter layer comprises a reflective perimeter layer;

wherein said perimeter layer comprises at least one thin metal film and wherein said perimeter layer is electrically conductive;

wherein said perimeter layer generally conceals said perimeter seal from view by a driver of the vehicle normally viewing said front substrate when said exterior rearview mirror assembly is mounted at the vehicle;

wherein said exterior rearview mirror assembly comprises a light source;

wherein said light source comprises at least one light emitting diode; and

wherein said light source comprises a light source of an indicator.

38. The exterior rearview mirror assembly of claim 37, wherein said indicator is disposed at said casing portion.

39. The exterior rearview mirror assembly of claim 37, wherein said indicator is disposed rearward of said mirror reflective element and, when actuated, illuminates through said mirror reflective element.

40. The exterior rearview mirror assembly of claim 37, wherein said indicator, at least when said light source is actuated, is viewable by a driver of the vehicle normally viewing said front substrate when said exterior rearview mirror assembly is mounted at the vehicle.

41. The exterior rearview mirror assembly of claim 37, wherein said indicator comprises a turn signal indicator.

42. The exterior rearview mirror assembly of claim 37, wherein said material of said first thin film has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm.

43. The exterior rearview mirror assembly of claim 42, wherein said material of said second thin film has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm.

44. The exterior rearview mirror assembly of claim 43, wherein said material of said first thin film is a metal and wherein said material of said second thin film is a metal.

45. The exterior rearview mirror assembly of claim 44, wherein said metal of said first thin film has a specific resistivity of less than about 5×

10<sup>−

4</sup> ohm·

cm and wherein said metal of said second thin film has a specific resistivity of less than about 5×

10<sup>−

4</sup> ohm·

cm.

46. The exterior rearview mirror assembly of claim 43, wherein said material of said first thin film is different than said material of said second thin film.

47. The exterior rearview mirror assembly of claim 46, wherein said first thin film comprises a first thin metal film and wherein said second thin film comprises a second thin metal film.

48. The exterior rearview mirror assembly of claim 47, wherein said mirror reflector is disposed at at least a portion of said third surface of said rear substrate.

49. The exterior rearview mirror assembly of claim 37, wherein at least one of (i) said front substrate has a thickness of about 0.063 inches or less, (ii) said rear substrate has a thickness of about 0.063 inches or less, (iii) said front substrate has a thickness of about 0.063 inches or less and said rear substrate has a thickness of about 0.063 inches or less, (iv) at least one of said front substrate and said rear substrate has a thickness of about 0.043 inches or less, and (v) one of said front substrate and said rear substrate has a thickness of about 0.063 inches or less and the other of said front substrate and said rear substrate has a thickness of about 0.043 inches or less.

50. The exterior rearview mirror assembly of claim 37, wherein said mirror reflector has a sheet resistance of less than about 5 ohms per square.

51. The exterior rearview mirror assembly of claim 37, wherein at least one of (i) said first thin film has a thickness of at least about 600 angstroms and (ii) said mirror reflector provides at least about 55 percent photopic reflectance measured in accordance with Society of Automotive Engineers test procedure SAE J964a.

52. The exterior rearview mirror assembly of claim 37, wherein said front and rear substrates comprise aspheric substrates, and wherein said mirror reflective element comprises a curved mirror reflective element having a more curved outboard region and a less curved inboard region, and wherein said exterior rearview mirror assembly comprises a demarcation that demarcates said more curved outboard region of said mirror reflective element from said less curved inboard region of said mirror reflective element.

53. The exterior rearview mirror assembly of claim 37, wherein said perimeter seal is at least partially visible to a person viewing through said rear substrate.

54. The exterior rearview mirror assembly of claim 37, wherein light that reflects off of said mirror reflector and passes through said electrochromic medium and said front substrate has a substantially untinted reflectant characteristic to a person normally viewing said front substrate of said mirror reflective element when no voltage is applied to said electrochromic medium.

55. An exterior rearview mirror assembly suitable for use for a vehicle, said exterior rearview mirror assembly comprising:

a casing portion;

wherein said casing portion comprises a variable reflectance mirror reflective element;

an attachment portion;

wherein said attachment portion is configured for attaching at a side of a vehicle;

wherein said exterior rearview mirror assembly comprises a driver-side exterior rearview mirror assembly;

wherein said mirror reflective element comprises a front substrate and a rear substrate and an electrochromic medium disposed between said front and rear substrates;

wherein said front substrate has a first surface and a second surface and wherein a transparent electrically conductive layer is disposed at said second surface of said front substrate;

wherein said rear substrate has a third surface and a fourth surface and wherein a mirror reflector is disposed at at least a portion of said third surface of said rear substrate;

wherein said mirror reflector comprises a stack of thin films and wherein said stack of thin films comprises at least a first thin film and a second thin film;

wherein said first thin film is formed of a material that has a specific resistivity of less than about 1×

10<sup>−

2</sup> ohm·

cm;

wherein said second thin film is formed of a material that has a specific resistivity of less than about 1×

10<sup>−

2</sup> ohm·

cm;

wherein said electrochromic medium is disposed in an interpane cavity between said third surface of said rear substrate and said second surface of said front substrate and is bounded by a perimeter seal;

wherein no part of said rear substrate extends beyond any part of said front substrate;

wherein a perimeter layer is disposed at said second surface of said front substrate proximate a perimeter edge of said front substrate, and wherein said perimeter layer comprises a reflective perimeter layer;

wherein said perimeter layer comprises at least one thin metal film and wherein said perimeter layer is electrically conductive;

wherein said perimeter layer generally conceals said perimeter seal from view by a driver of the vehicle normally viewing said front substrate when said exterior rearview mirror assembly is mounted at the vehicle;

wherein said mirror reflective element comprises a curved mirror reflective element having a more curved outboard region and a less curved inboard region;

a demarcation that demarcates said more curved outboard region of said mirror reflective element from said less curved inboard region of said mirror reflective element; and

wherein at least one of (i) said front substrate has a thickness of about 0.063 inches or less, (ii) said rear substrate has a thickness of about 0.063 inches or less, (iii) said front substrate has a thickness of about 0.063 inches or less and said rear substrate has a thickness of about 0.063 inches or less, (iv) at least one of said front substrate and said rear substrate has a thickness of about 0.043 inches or less, and (v) one of said front substrate and said rear substrate has a thickness of about 0.063 inches or less and the other of said front substrate and said rear substrate has a thickness of about 0.043 inches or less.

56. The exterior rearview mirror assembly of claim 55, wherein said exterior rearview mirror assembly comprises a light source.

57. The exterior rearview mirror assembly of claim 56, wherein said light source comprises at least one light emitting diode.

58. The exterior rearview mirror assembly of claim 56, wherein said light source comprises a light source of an indicator.

59. The exterior rearview mirror assembly of claim 56, wherein said light source comprises a light source of a ground illumination light that, when said light source is actuated, illuminates a ground area generally at the side of the vehicle at which said attachment element is attached when said exterior rearview mirror assembly is mounted at the vehicle.

60. The exterior rearview mirror assembly of claim 56, wherein said light source comprises a light source of an indicator that is at least one of (i) disposed rearward of said mirror reflective element and, when actuated, illuminates through said mirror reflective element, and (ii) disposed at said casing portion.

61. The exterior rearview mirror assembly of claim 55, wherein said material of said first thin film has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm.

62. The exterior rearview mirror assembly of claim 61, wherein said material of said second thin film has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm.

63. The exterior rearview mirror assembly of claim 62, wherein said material of said first thin film is a metal and wherein said material of said second thin film is a metal.

64. The exterior rearview mirror assembly of claim 63, wherein said metal of said first thin film has a specific resistivity of less than about 5×

10<sup>−

4</sup> ohm·

cm and wherein said metal of said second thin film has a specific resistivity of less than about 5×

10<sup>−

4</sup> ohm·

cm.

65. The exterior rearview mirror assembly of claim 63, wherein said metal of said first thin film is different than said metal of said second thin film.

66. The exterior rearview mirror assembly of claim 55, wherein said first thin film comprises a first thin metal film and wherein said second thin film comprises a second thin metal film.

67. The exterior rearview mirror assembly of claim 55, wherein said mirror reflector has a sheet resistance of less than about 5 ohms per square.

68. The exterior rearview mirror assembly of claim 55, wherein at least one of (i) said first thin film has a thickness of at least about 600 angstroms and (ii) said mirror reflector provides at least about 55 percent photopic reflectance measured in accordance with Society of Automotive Engineers test procedure SAE J964a.

69. The exterior rearview mirror assembly of claim 55, wherein said perimeter seal is at least partially visible to a person viewing through said rear substrate.

70. The exterior rearview mirror assembly of claim 55, wherein light that reflects off of said mirror reflector and passes through said electrochromic medium and said front substrate has a substantially untinted reflectant characteristic to a person normally viewing said front substrate of said mirror reflective element when no voltage is applied to said electrochromic medium.

71. The exterior rearview mirror assembly of claim 55, wherein said front and rear substrates comprise aspheric substrates.

72. An exterior rearview mirror assembly suitable for use for a vehicle, said exterior rearview mirror assembly comprising:

a casing portion;

wherein said casing portion comprises a variable reflectance mirror reflective element;

an attachment portion;

wherein said attachment portion is configured for attaching at a side of a vehicle;

wherein said mirror reflective element comprises a front substrate and a rear substrate and an electrochromic medium disposed between said front and rear substrates;

wherein said front substrate has a first surface and a second surface and wherein a transparent electrically conductive layer is disposed at said second surface of said front substrate;

wherein said rear substrate has a third surface and a fourth surface and wherein a mirror reflector is disposed at at least a portion of said third surface of said rear substrate;

wherein said mirror reflector comprises a stack of thin films and wherein said stack of thin films comprises at least a first thin metal film and a second thin metal film;

wherein said first thin metal film is formed of a metal that has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm;

wherein said second thin metal film is formed of a metal that has a specific resistivity of less than about 1×

10<sup>−

3</sup> ohm·

cm;

wherein said electrochromic medium is disposed in an interpane cavity between said third surface of said rear substrate and said second surface of said front substrate and is bounded by a perimeter seal;

wherein no part of said rear substrate extends beyond any part of said front substrate;

wherein a perimeter layer is disposed at said second surface of said front substrate proximate a perimeter edge of said front substrate, and wherein said perimeter layer comprises a reflective perimeter layer;

wherein said perimeter layer comprises at least one thin metal film and wherein said perimeter layer is electrically conductive;

wherein said perimeter layer generally conceals said perimeter seal from view by a driver of the vehicle normally viewing said front substrate when said exterior rearview mirror assembly is mounted at the vehicle;

wherein said exterior rearview mirror assembly comprises a light source; and

wherein light that reflects off of said mirror reflector and passes through said electrochromic medium and said front substrate has a substantially untinted reflectant characteristic to a person normally viewing said front substrate of said mirror reflective element when no voltage is applied to said electrochromic medium.

73. The exterior rearview mirror assembly of claim 72, wherein said exterior rearview mirror assembly comprises a light source.

74. The exterior rearview mirror assembly of claim 73, wherein said light source comprises at least one light emitting diode.

75. The exterior rearview mirror assembly of claim 73, wherein said light source comprises a light source of an indicator.

76. The exterior rearview mirror assembly of claim 73, wherein said light source comprises a light source of a ground illumination light that, when said light source is actuated, illuminates a ground area generally at the side of the vehicle at which said attachment element is attached when said exterior rearview mirror assembly is mounted at the vehicle.

77. The exterior rearview mirror assembly of claim 72, wherein said mirror reflector has a sheet resistance of less than about 5 ohms per square.

78. The exterior rearview mirror assembly of claim 72, wherein said perimeter seal is at least partially visible to a person viewing through said rear substrate.

79. The exterior rearview mirror assembly of claim 72, wherein said metal of said first thin metal film is different than said metal of said second thin metal film.

80. The exterior rearview mirror assembly of claim 72, wherein said metal of said first thin film has a specific resistivity of less than about 5×

10<sup>−

4</sup> ohm·

cm and wherein said metal of said second thin film has a specific resistivity of less than about 5×

10<sup>−

4</sup> ohm·

cm.

81. The exterior rearview mirror assembly of claim 72, wherein said mirror reflective element comprises a curved mirror reflective element having a more curved outboard region and a less curved inboard region.

82. The exterior rearview mirror assembly of claim 81, comprising a demarcation that demarcates said more curved outboard region of said mirror reflective element from said less curved inboard region of said mirror reflective element.

83. The exterior rearview mirror assembly of claim 72, wherein at least one of (i) said front substrate has a thickness of about 0.063 inches or less, (ii) said rear substrate has a thickness of about 0.063 inches or less, (iii) said front substrate has a thickness of about 0.063 inches or less and said rear substrate has a thickness of about 0.063 inches or less, (iv) at least one of said front substrate and said rear substrate has a thickness of about 0.043 inches or less, and (v) one of said front substrate and said rear substrate has a thickness of about 0.063 inches or less and the other of said front substrate and said rear substrate has a thickness of about 0.043 inches or less.