Electrochromic mirror with two thin glass elements and a gelled electrochromic medium

• US 6,057,956 A
• Filed: 08/16/1999
• Issued: 05/02/2000
• Est. Priority Date: 04/02/1997
• Status: Expired due to Term

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Tonar, William L., Bauer, Frederick T., Ash, Kevin L.
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): LETENDRE, SUZANNE M
• Application Number:
  US09/375,136
• Time in Patent Office: 260 Days
• Field of Search: 359/265, 359/267, 359/270, 359/273, 359/274, 359/266, 359/272, 359/513
• US Class Current: 359/267
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: C09K 9/02 Organic tenebrescent materials
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions
• CPC Class Codes: G02F 1/15165 Polymers
• CPC Class Codes: G02F 1/161 Gaskets; Spacers; Sealing of cells; Filling or closing of cells
• CPC Class Codes: G02F 2001/1502 complementary cell
• CPC Class Codes: G02F 2001/15145 the electrochromic layer comprises a mixture of anodic and cathodic compounds

Abstract

An improved electrochromic rearview mirror for motor vehicles, the mirror incorporating thin front and rear spaced glass elements having a thickness ranging from about 0.5 to about 1.5. A layer of transparent conductive material is placed onto the mirror'"'"'s second surface, and either another layer of transparent conductive material or a combined reflector/electrode is placed onto the mirror'"'"'s third surface. A chamber, defined by the layers on the interior surfaces of the front and rear glass elements and a peripheral sealing member, contains a free-standing gel comprising a solvent and a crosslinked polymer matrix. The chamber further contains at least one electrochromic material in solution with the solvent and interspersed in the crosslinked polymer matrix. The gel cooperatively interacts with the thin glass elements to form a thick, strong unitary member which is resistant to flexing, warping, bowing and/or shattering and further allows the mirror to exhibit reduced vibrational distortion and double imaging.

Claims

1. A color matched inside/outside mirror system, comprising:

a first electrochromic mirror adapted to be installed on the outside of a motor vehicle, comprising front and rear spaced elements, each of said front and rear elements being bent;

a color neutral layer of a transparent conductive material disposed on said rear surface of said front element;

a reflector disposed on one side of said rear element provided that, if said reflector is on said rear surface of said rear element, then said front surface of said rear element contains a layer of a transparent conductive material;

a perimeter sealing member bonding together said front and rear spaced elements in a spaced-apart relationship to define a chamber therebetween, where said chamber contains at least one electrochromic material;

a second electrochromic mirror adapted to be installed on the inside of a motor vehicle comprising;

front and rear spaced elements, each having front and rear surfaces;

a layer of color neutral transparent conductive material disposed on said rear surface of said front element;

a reflector disposed on one side of said rear element provided that, if said reflector is on said rear surface of said rear element, then said front surface of said rear element contains a layer of a transparent conductive material; and

a perimeter sealing member bonding together said front and rear spaced elements in a spaced-apart relationship to define a chamber therebetween, where said chamber contains at least one electrochromic material;

where said reflector material is effective to reflect light through said chamber and said front element when said light reaches said reflector after passing through said front element and said chamber.

2. The color matched mirror system according to claim 1, where said transparent conductive material disposed on said rear surface of said front element of said second electrochromic mirror is applied at atmospheric pressure via chemical vapor deposition.

3. The color matched mirror system according to claim 2, where said layer of transparent conductive material disposed on said inside mirror is deposited on a glass manufacturing float-line.

4. The color matched mirror system according to claim 2, where said layer of transparent conductive material disposed on said inside mirror is fluorine-doped tin oxide.

5. The color matched mirror system according to claim 1, where said layer of transparent conductive material disposed on said first mirror is a multi-layer stack having a first layer with a high refractive index, a second layer with a low refractive index and a third layer with a high refractive index.

6. The color matched mirror system according to claim 5, where said first layer comprises ITO and has a thickness between about 200 angstroms and about 400 angstroms, said second layer comprises SiO₂ and has a thickness of between about 200 angstroms and about 400 angstroms, and said third layer comprises ITO and has a thickness of about 1500 angstroms.

7. A color matched inside/outside mirror system, comprising:

a first electrochromic mirror adapted to be installed on the outside of a motor vehicle, comprising;

front and rear spaced elements, each having a thickness ranging from about 0.5 mm to about 1.5 mm and each having front and rear surfaces and each being bent;

a layer of color-neutral transparent conductive material disposed on said rear surface of said front element;

a reflector disposed on one side of said rear element provided that, if said reflector is on said rear surface of said rear element, then said front surface of said rear element contains a layer of a transparent conductive material; and

a perimeter sealing member bonding together said front and rear spaced elements in a spaced-apart relationship to define a chamber therebetween, where said chamber contains at least one electrochromic material;

where said reflector material is effective to reflect light through said chamber and said front element when said light reaches said reflector after passing through said front element and said chamber; and

a second electrochromic mirror adapted to be installed on the inside of a motor vehicle, comprising;

front and rear spaced elements, each having front and rear surfaces;

a layer of color neutral transparent conductive material disposed on said rear surface of said front element;

a reflector disposed on one side of said rear element provided that, if said reflector is on said rear surface of said rear element, then said front surface of said rear element contains a layer of a transparent conductive material; and

a perimeter sealing member bonding together said front and rear spaced elements in a spaced-apart relationship to define a chamber therebetween, where said chamber contains at least one electrochromic material;

where said reflector material is effective to reflect light through said chamber and said front element when said light reaches said reflector after passing through said front element and said chamber;

where said first and said second electrochromic mirrors are color-matched.

8. The color matched mirror system according to claim 7, where said layer of transparent conductive material disposed on said outside mirror is a multi-layer stack having a first layer with a high refractive index, a second layer with a low refractive index and a third layer with a high refractive index.

9. The color matched mirror system according to claim 8, where said first layer comprises ITO and has a thickness between about 200 angstroms and about 400 angstroms, said second layer comprises SiO₂ and has a thickness of between about 200 angstroms and about 400 angstroms, and said third layer comprises ITO and has a thickness of about 1500 angstroms.

10. The color matched mirror system according to claim 8, where said layer of transparent conductive material disposed on said inside mirror is deposited on a glass manufacturing float-line.

11. The color matched mirror system according to claim 10, where said layer of transparent conductive material disposed on said inside mirror is fluorine-doped tin oxide.

12. The color matched mirror system according to claim 7, where said front and rear spaced elements of said outside electrochromic mirror are bent.

13. An electrochromic variable reflectance mirror for motor vehicles, comprising:

front and rear spaced elements, each having front and rear surfaces;

a layer of transparent conductive material disposed on said rear surface of said front element;

a reflector disposed on one side of said rear element provided that, if said reflector is on said rear surface of said rear element, then said front surface of said rear element contains a layer of a transparent conductive material; and

a perimeter sealing member bonding together said front and rear spaced elements in a spaced-apart relationship to define a chamber therebetween, where said chamber comprises at least one electrochromic material;

where said variable reflectance mirror has a first mode horizontal frequency of greater than about 45 Hertz.

14. The electrochromic mirror of claim 13, where said first mode of horizontal frequency is greater than about 55 Hertz.

15. The electrochromic mirror of claim 13, where said first mode of horizontal frequency is greater than about 60 Hertz.