Electrochromic mirrors and other electrooptic devices

• US 7,738,155 B2
• Filed: 10/29/2007
• Issued: 06/15/2010
• Est. Priority Date: 03/05/2003
• Status: Active Grant

• Current Assignee: Ajjer, LLC
• Original Assignee: Electro Chromix Incorporated
• Inventors: Lopez, Juan Carlos, Agrawal, Anoop, Cronin, John P., LeCompte, Robert S.
• Primary Examiner(s): MARTINEZ, JOSEPH P
• Application Number:
  US11/927,462
• Publication Number:
  US 20080074724A1
• Time in Patent Office: 960 Days
• Field of Search: 359/265, 359/273, 359/839
• US Class Current: 359/265
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: C09J 163/00 Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
• CPC Class Codes: C09K 9/02 Organic tenebrescent materials
• CPC Class Codes: G02F 1/1525 characterised by a particular ion transporting layer, e.g. electrolyte
• CPC Class Codes: G02F 1/161 Gaskets; Spacers; Sealing of cells; Filling or closing of cells
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

This invention focuses on electrooptic devices and in particular on electrochromic devices with many aspects directed towards automotive EC mirrors. There are several ways to improve these products and their processing using this invention and some of the prominent ones are outlined below. This invention improves on the devices by disclosing new compositions for electrodes and methods of depositing them. It also addresses novel ways to provide busbars to power these devices in order to improve their performance. The device processing attributes and performance are also improved by adhesive compositions and solid electrolytes disclosed herein. In addition sensors are also disclosed which are novel for use in electrochromic mirrors. The invention also discloses how the electrolytes comprising ionic liquids have no adverse effect on attributes of commercial EC mirrors and often result in improved performance and/or feature enhancements.

Claims

1. An electrochromic variable reflectance mirror for vehicles comprising front and rear spaced elements, said rear surface of the front element having a layer of transparent conductive coating disposed thereon, and said front surface of said rear element comprises a reflective element having at least one layer of conductive coating deposited on a front surface thereof, where the front and the rear elements are sealably bonded together by a spaced apart relationship defining a chamber therebetween, said chamber containing an electrochromic medium, and wherein the conductive front surface of the reflective rear element is connected by a conductive path to the rear surface of the reflective rear element, the conductive path comprising (a) a portion of the conductive coating deposited on the front surface thereof, (b) conductive material deposited on a portion of the rear surface thereof, and (c) conductive material deposited on the edge of the reflective rear element and extending along the edge thereof from the conductive material on the front surface to the conductive material on the rear surface.

2. An electrochromic variable reflectance mirror for vehicles as in claim 1 wherein said conductive path is formed by any one of physical vapor deposition, electroless deposition, electro-deposition, spray process and deposition of a conductive adhesive or a conductive frit.

3. An electrochromic variable reflectance mirror for vehicles as in claim 1 wherein said conductive path comprises a busbar.

4. An electrochromic variable reflectance mirror for vehicles as in claim 3, wherein said busbar is further coated with a non-conductive material.

5. An electrochromic variable reflectance mirror assembly for vehicles comprising front and rear spaced elements, said rear surface of the front element having a layer of transparent conductive coating disposed thereon, said rear element being reflective and said front surface of said rear element having at least one layer of conductive coating disposed thereon, where the front and the rear elements are sealably bonded together by a spaced apart relationship defining a chamber therebetween, said chamber containing an electrochromic medium, wherein a conductive busbar is deposited on the conductive surface of the front elements along its perimeter, such that the electrical resistance in ohms of the said busbar in a length of about half the perimeter of the said front element is at least two times less than the surface resistivity in ohms/square of the transparent conductor on which it is deposited.

6. An electrochromic variable reflectance mirror assembly as in claim 5 wherein the said busbar is protected by an electrically insulating material.

7. The electrochromic variable reflectance mirror assembly for vehicles, as defined in claim 5, wherein the said front element is larger than the said rear element and a perimeter busbar for the transparent front element occupies more than 50 percent of the said mirror assembly perimeter).

8. The electrochromic variable reflectance mirror assembly for vehicles, as defined in claim 7, wherein the perimeter busbar for the transparent front element comprises a perimeter conductive portion of a layer of conductive material deposited on the transparent front element.

9. The electrochromic variable reflectance mirror assembly for vehicles, as defined in claim 5, wherein the reflective rear element has a perimeter conductive connector that comprises (a) a portion of the conductive coating deposited on the front surface thereof, (b) conductive material deposited on a portion of the rear surface thereof, and (c) conductive material deposited on the edge of the reflective rear element and extending along the edge thereof from the conductive material on the front surface to the conductive material on the rear surface.

10. The electrochromic variable reflectance mirror assembly for vehicles, as defined in claim 9, wherein the perimeter conductive connector for the reflective rear element occupies less than 50 percent of the said mirror assembly perimeter.