Electro-optic system configured to reduce a perceived color change

• US 9,096,181 B2
• Filed: 02/23/2015
• Issued: 08/04/2015
• Est. Priority Date: 08/09/2010
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Baumann, Kelvin L., VanderPloeg, John A., Theiste, David A., Guarr, Thomas F., Luten, Henry A., Neuman, George A., Anderson, John S.
• Primary Examiner(s): Jones, James
• Application Number:
  US14/628,592
• Publication Number:
  US 20150175075A1
• Time in Patent Office: 162 Days
• Field of Search: 359/265
• US Class Current: 1/1
• CPC Class Codes: B60R 1/08 involving special optical features, e.g. avoiding blind spots , e.g. convex mirrors; Side-by-side associations of rear-view and other mirrors B60R1/025, B60R1/10 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 1/12 Mirror assemblies combined with other articles, e.g. clocks
• CPC Class Codes: B60R 1/1207 with lamps; with turn indicators
• CPC Class Codes: B60R 2001/1215 with information displays
• 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 electro-optic system is provided that includes a front element having first and second surfaces, a rear element including third and fourth surfaces, wherein the front and rear elements are sealably bonded together in a spaced-apart relationship to define a chamber, and an electro-optic medium contained in the chamber, and the electro-optic medium is adapted to be in at least a high transmittance state and a low transmittance state. The electro-optic system further includes a display device in optical communication with the electro-optic element, the display device including at least one light source and is configured to emit at least a first primary and a second primary, the first and second primaries each having a first hue (h_ab) when viewed through the electro-optic element in approximately the high transmittance state and a second hue (h_ab′) when viewed through the electro-optic element in approximately the low transmittance state, wherein a change in the first and second hues (Δh_ab) for both first and second primaries is less than approximately 31 degrees.

Claims

1. An electrochromic system comprising:

an electrochromic element comprising;

a front element comprising first and second surfaces;

a rear element comprising third and fourth surfaces, wherein said front and rear elements are sealably bonded together in a spaced-apart relationship to define a chamber, such that said second surface and said third surface face one another; and

an electrochromic medium contained in said chamber, wherein said electrochromic medium is adapted to be in at least a high transmittance state and a low transmittance state;

a reflector electrode on said third surface; and

a transparent electrode on said second surface;

wherein said transparent electrode is selected to have a beneficial effect on the reflected color of said electrochromic element, such that during a color excursion the reflected C* remains below approximately 20; and

wherein light passing through at least a portion of said electrochromic element has at least a first primary and a second primary, and said first and said second primaries each have a first hue (h_ab) when viewed through said electrochromic medium in said high transmittance state and a second hue (h_ab′

) when viewed through said electrochromic element in approximately said low transmittance state, wherein a change in said first and second hues (Δ

h_ab) for both said first and second primaries is less than approximately 31 degrees.

2. The electrochromic system of claim 1, wherein each of said first and second primaries has a first color (u′

,v′

) when passing through at least a portion of said electrochromic element in approximately said high transmittance state and a second color (u′

,v′

)′

when passing through at least a portion of said electrochromic element in approximately said low transmittance state, and a difference in said first and second colors (Δ

E<sub>u′

,v′</sub>

) for said first and second primaries is less than approximately 0.06.

3. The electrochromic system of claim 1, wherein said first primary is light having a red hue and said second primary is light having a green hue.

4. The electrochromic system of claim 1, wherein a third primary having a first hue (h_ab) when passing through at least a portion of said electrochromic element in approximately said high transmittance state and a second hue (h_ab′

) when received through said electrochromic element in approximately said low transmittance state, and a change in said first and second hues (Δ

h_ab) is less than approximately 41 degrees.

5. The electrochromic system of claim 4, wherein said third primary has a first color (u′

,v′

) when passing through at least a portion of said electrochromic element in approximately said high transmittance state and a second color (u′

,v′

)′

when received through said electrochromic element in approximately said low transmittance state, and a difference in said first and second colors (Δ

E<sub>u′

,v′</sub>

) for said third primary is less than approximately 0.05.

6. The electrochromic system of claim 4, wherein said third primary is light having a blue hue.

7. The electrochromic system of claim 1, wherein a fourth primary has a first color (u′

,v′

) when passing through at least a portion of said electrochromic element in approximately said high transmittance state and a second color (u′

,v′

) when passing through at least a portion of said electrochromic element in approximately said low transmittance state, and a difference in said first and second colors (Δ

E<sub>u′

,v′</sub>

) for said fourth primary is less than approximately 0.05.

8. The electrochromic system of claim 7, wherein said fourth primary is light having a yellow hue.

9. The electrochromic system of claim 1, wherein said transparent electrode is a single transparent conducting oxide layer.

10. The electrochromic system of claim 1, wherein a thickness of said transparent conducting oxide is between and includes approximately 70 nm and approximately 210 nm.

11. The electrochromic system of claim 10, wherein said thickness of said transparent conducting oxide is between and includes approximately 120 nm and approximately 140 nm.

12. The electrochromic system of claim 1, wherein said transparent electrode is IMI.

13. The electrochromic system of claim 1, wherein said transparent electrode is color suppressed TCO.

14. The electrochromic system of claim 1, wherein said C* remains below approximately 15.

15. The electrochromic system of claim 14, wherein said C* remains below approximately 10.

16. The electrochromic system of claim 1, wherein a low end reflectance of said electrochromic element is less than approximately 18.

17. The electrochromic system of claim 16, wherein said low end reflectance is below approximately 10.8.

18. The electrochromic system of claim 1, wherein said electrochromic element in said high transmittance state has a reflectance of greater than approximately 35%.

19. The electrochromic system of claim 18, wherein said electrochromic element in said high transmittance state has a reflectance of greater than approximately 50%.

20. The electrochromic system of claim 1 further comprising at least one of a display and a sensor.