OPTICAL ELEMENT HAVING AN APODIZED APERTURE

• US 20100134866A1
• Filed: 12/02/2009
• Published: 06/03/2010
• Est. Priority Date: 12/03/2008
• Status: Active Grant

• Current Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Original Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Inventors: Tang, Robert H., Blackburn, Forrest R., Seybert, Kevin W., Walters, Robert W., Foller, Peter C.
• Granted Patent: US 8,373,919 B2
• Time in Patent Office: Days
• US Class Current: 359/275
• CPC Class Codes: G02F 1/1533 structural features not otherwise provided for
• CPC Class Codes: G02F 1/155 Electrodes
• CPC Class Codes: G02F 1/163 Operation of electrochromic cells, e.g. electrodeposition cells; Circuit arrangements therefor
• CPC Class Codes: G02F 1/291 Two-dimensional analogue deflection
• CPC Class Codes: G03B 9/02 Diaphragms

Abstract

Provided is an optical element with an electrochromic apodized aperture having variable light transmittance in response to the amplitude of an applied voltage. The apodized aperture includes (i) a first substrate having a planar inner surface and an outer surface, (ii) a second substrate having an outer surface and a non-planar inner surface opposing and spaced from the planar inner surface of the first substrate, wherein each of the planar inner surface of the first substrate and the non-planar inner surface of the second substrate has an at least partial layer of transparent conductive material thereover; and (iii) an electrochromic medium disposed between the planar inner surface of the first substrate and the non-planar inner surface of the second substrate.

Claims

1. An optical element comprising an electrochromic apodized aperture having variable light transmittance in response to the magnitude of an applied electrical voltage,

the apodized aperture comprising

(i) a first substrate having a planar inner surface and an outer surface, wherein the planar inner surface has an at least partial layer of transparent conductive material thereover;

(ii) a second substrate having an outer surface and a non-planar inner surface opposing the planar inner surface of the first substrate, wherein the non-planar inner surface has an at least partial layer of transparent conductive material thereover; and

(iii) an electrochromic medium disposed between the planar inner surface of the first substrate and the non-planar inner surface of the second substrate.

2. The optical element of claim 1, wherein the refractive indices of the second substrate, and the electrochromic medium are substantially the same.

3. The optical element of claim 1, wherein the refractive index of the first substrate is substantially the same as the refractive indices of the second substrate and the electrochromic medium.

4. The optical element of claim 1, wherein at least one of the outer surface of the first substrate (i) and the outer surface of the second substrate (ii) is substantially planar.

5. The optical element of claim 1, wherein the at least partial layer of transparent conductive material on the planar inner surface of the first substrate (i) and the at least partial layer of transparent conductive material on the non-planar surface of the second substrate (ii) provides a surface conductivity ranging from 1 to 1000 ohms/square.

6. The optical element of claim 1, wherein the at least partial layer of transparent conductive material on the non-planar inner surface of the second substrate (ii) opposes and is spaced from the at least partial layer of transparent conductive material on the planar inner surface of the first substrate (i).

7. The optical element of claim 1, wherein a center region of the electrochromic apodized aperture defines a pupilary region.

8. The optical element of claim 7, wherein the non-planar inner surface of the second substrate (ii) is essentially free of the transparent conductive material in the pupilary region.

9. The optical element of claim 7, wherein the transparent conductive material on at least one of the inner surface of the first substrate (i) and the inner surface of the second substrate (ii) is electrically isolated in the pupilary region.

10. The optical element of claim 1, wherein the electrochromic medium comprises a solvent-phase electrochromic medium.

11. The optical element of claim 10, wherein the solvent-phase electrochromic medium is in the form of a liquid.

12. The optical element of claim 1, wherein the non-planar inner surface of the second substrate is convex.

13. The optical element of claim 1, wherein the apodized aperture is characterized by a Gaussian radial transmittance curve.

14. The optical element of claim 1, wherein the thickness of the electrochromic medium increases along a radius of the apodized aperture.

15. The optical element of claim 1, wherein the thickness of the electrochromic medium varies with the non-planar inner surface of the second substrate.

16. The optical element of claim 1, wherein the conductive material comprises a transparent conductive material selected from carbon nanotubes, gold, tin oxide, fluorine-doped tin oxide, and/or indium tin oxide.

17. The optical element of claim 1, wherein the first substrate and the second substrate comprise the same or different materials.

18. The optical element of claim 17, wherein the first substrate and/or the second substrate comprises glass.

19. The optical element of claim 18, wherein the first substrate and/or the second substrate comprises glass having a refractive index of 1.40 to 1.75.

20. The optical element of claim 17, wherein the first substrate and/or the second substrate comprises a polymeric substrate.

21. The optical element of claim 20, wherein the first substrate and/or the second substrate comprises a polymeric substrate having a refractive index of 1.30 to 1.75.

22. The optical element of claim 16, wherein the polymeric substrate comprises polycarbonates, polyurethanes, poly(cyclic) olefins, polystyrenes, polymethacrylates, co-polymers thereof, or mixtures of any of the foregoing.

23. The optical element of claim 1, wherein the first substrate (i) and the second substrate (ii) are transparent.

24. The optical element of claim 1, wherein the electrochromic medium comprises phenazine compounds and/or viologen compounds.

25. The optical element of claim 1, wherein the electrochromic medium comprises propylene carbonate, benzonitrile, and/or phenoxyacetonitrile.

26. The optical element of claim 1, wherein the electrochromic apodized aperture further comprises (iv) at least one seal member about the outer perimeter of the apodized aperture and in contact with the first substrate (i), the second substrate (ii), and the electrochromic medium (iii).

27. The optical element of claim 1, wherein the outer surface of the first substrate (i) and/or the outer surface of the second substrate (ii) is at least partially coated with at least one coating chosen from protective coatings, antifogging coatings, oxygen barrier coatings, antireflective coatings, IR absorbing coatings, IR reflective coatings, and/or conventional reflective coatings.

28. An optical element comprising an electrochromic apodized aperture having variable light transmittance in response to the magnitude of an applied voltage,

the apodized aperture comprising:

(i) a first substrate having an outer surface and a planar inner surface, and

(ii) a second substrate having an outer surface and a convex inner surface opposing and spaced from the planar inner surface of the first substrate to form a cavity therebetween,

wherein each of the planar inner surface and the convex inner surface has an at least partial layer of transparent conductive material thereover, the conductive material comprising indium tin oxide; and

(iii) an electrochromic medium disposed within the cavity.

29. The optical element of claim 28, wherein the refractive indices of the second substrate, and the electrochromic medium differ by not more than +/−

0.003.

30. The optical element of claim 28, wherein the refractive indices of the first substrate (i), the second substrate (ii), and the electrochromic medium (iii) differ by not more than +/−

0.003.

31. The optical element of claim 28, wherein at least one of the outer surface of the first substrate (i) and the outer surface of the second substrate (ii) is substantially planar.

32. The optical element of claim 28, wherein the electrochromic apodized aperture further comprises (iv) at least one seal member about the outer perimeter of the apodized aperture and in contact with the first substrate (i), the second substrate (ii), and the electrochromic medium (iii).