Electro-optic infrared filter

• US 10,429,711 B2
• Filed: 07/25/2017
• Issued: 10/01/2019
• Est. Priority Date: 07/26/2016
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Luten, Henry A., Kloeppner, Leroy J., Stephenson, Michael T., Giri, Punam
• Primary Examiner(s): Ben, Loha
• Application Number:
  US15/658,758
• Publication Number:
  US 20180031940A1
• Time in Patent Office: 798 Days
• Field of Search: 359245, 359265, 359269, 359275, 359321, 359448, 359609, 345 48, 345 49, 345 84, 345105, 345106, 345204-206, 349 5, 349 58, 349 95, 349158, 396457, 396506, 348 E5028
• CPC Class Codes: G02F 1/15 based on an electrochromic effect
• CPC Class Codes: G02F 1/153 Constructional details
• CPC Class Codes: G02F 2203/11 involving infrared radiation
• CPC Class Codes: G02F 2203/58 Multi-wavelength, e.g. operation of the device at a plurality of wavelengths
• CPC Class Codes: G09G 3/19 using electrochromic devices
• CPC Class Codes: G09G 3/38 using electrochromic devices
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

An imaging system is provided that includes an imager, an optical lens stack, and an electro-optic element positioned between the imager and the lens stack. The electro-optic element includes a first substantially transparent substrate defining first and second surfaces. The second surface includes a first electrically conductive layer. A second substantially transparent substrate defines third and fourth surfaces. The third surface has a second electrically conductive layer. A primary seal is disposed between the first and second substrates. The seal and the first and second substrates define a cavity therebetween. An electro-optic medium is disposed within the cavity. The electro-optic medium is operable between substantially clear and substantially opaque states.

Claims

1. An imaging system, comprising:

an imager;

an optical lens stack; and

an electro-optic element positioned between the imager and the lens stack, the electro-optic element comprising;

a first substantially transparent substrate defining first and second surfaces, wherein the second surface comprises a first electrically conductive layer;

a second substantially transparent substrate defining third and fourth surfaces, wherein the third surface comprises a second electrically conductive layer;

a primary seal disposed between the first and second substrates, wherein the seal and the first and second substrates define a cavity therebetween; and

an electro-optic medium disposed within the cavity, the electro-optic medium operable between substantially clear and substantially opaque states for at least one wavelength band.

2. The imaging system of claim 1, wherein the electro-optic element is substantially opaque to infrared light in the substantially opaque state.

3. The imaging system of claim 1, wherein the electro-optic medium is substantially transparent to visible light in the substantially opaque state.

4. The imaging system of claim 1, wherein the electro-optic medium is substantially opaque to a wavelength band of light having a wavelength greater than about 700 nm in the substantially opaque state.

5. The imaging system of claim 1, wherein the electro-optic medium is substantially opaque to a wavelength band of light having a wavelength greater than about 650 nm in the substantially opaque state.

6. The imaging system of claim 1, wherein the electro-optic medium is an electrochromic medium.

7. The imaging system of claim 6, wherein the optical lens stack comprises two or more lenses.

8. A vehicle imaging system, comprising:

an imager;

an optical lens stack; and

an electro-optic element positioned in the imaging system, the electro-optic element comprising;

a first substantially transparent substrate defining first and second surfaces;

a second substantially transparent substrate defining third and fourth surfaces;

a primary seal disposed between the first and second substrates, wherein the seal and the first and second substrates define a cavity therebetween; and

an electro-optic medium disposed within the cavity, wherein the electro-optic medium is in contact with an electrically conductive layer that is configured to adjust the electro-optic medium between substantially transparent and substantially opaque states to at least one wavelength of infrared light.

9. The vehicle imaging system of claim 8, wherein the electro-optic medium is substantially transparent to visible light when substantially opaque to infrared light.

10. The vehicle imaging system of claim 8, wherein the optical lens stack comprises two or more lenses.

11. The vehicle imaging system of claim 10, wherein the electro-optic element is positioned between the two or more lenses of the optical lens stack.

12. The vehicle imaging system of claim 8, wherein the electro-optic medium in the substantially opaque state is substantially opaque to light having a wavelength greater than about 700 nm.

13. The vehicle imaging system of claim 8, wherein the electro-optic medium in the substantially opaque state is substantially opaque to light having a wavelength greater than about 650 nm.

14. A vehicle imaging system, comprising:

an imager;

an optical lens stack; and

an electro-optic element positioned in the imaging system, the electro-optic element comprising;

a first substrate defining first and second surfaces;

a second substrate defining third and fourth surfaces, the first and second substrates positioned in a spaced apart configuration; and

an electro-optic medium positioned between the first and second substrates and in electrical communication with an electrically conductive layer, the electro-optic medium being variably transmissive to at least infrared light.

15. The vehicle imaging system of claim 14, wherein the electro-optic medium is an electrochromic medium.

16. The vehicle imaging system of claim 14, wherein the electro-optic element is positioned between the optical lens stack and the imager.

17. The vehicle imaging system of claim 14, wherein the electro-optic medium is substantially transparent to visible light.

18. The vehicle imaging system of claim 14, wherein the electro-optic medium is variably transmissive to a wavelength band of light having a wavelength greater than about 700 nm.

19. The vehicle imaging system of claim 14, wherein the electro-optic medium is variably transmissive to a wavelength band of light having a wavelength greater than about 650 nm.

20. The vehicle imaging system of claim 14,

wherein the electrically conductive layer is positioned on at least one of the second and third surfaces.