Patent ID: 8797627

Claim:
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 −2 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; 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; wherein said light source comprises a plurality of light emitting diodes, and wherein at least some of said light emitting diodes each individually passes less than about 75 milliamps forward current when powered; and wherein light emitted by said light source when powered is substantially not visible to the driver of the vehicle when the driver is normally operating the vehicle.