Elastomeric optical device and related operation methods

Patent metadata

Field	Value
Publication number	US-11340479-B2
Application number	US-202016864837-A
Country	US
Kind code	B2
Filing date	May 1, 2020
Priority date	May 17, 2018
Publication date	May 24, 2022
Grant date	May 24, 2022

Abstract

The invention provides an elastomeric optical device having a first optical state and a second optical state. The device is transparent when in the first optical state and translucent or opaque when in the second optical state. The device comprises, in sequence, a first transparent electrode, a dielectric layer, an elastomer layer, and a second transparent electrode. The elastomer layer preferably has certain mechanical properties, such as a Shore OOO hardness of less than 15, and/or certain chemical properties, such as being substantially devoid of unreacted sites. The second transparent electrode is configured to compress the elastomer layer in response to an electric field between the first and second transparent electrodes, such that when the elastomeric optical device is in the second optical state, the elastomer layer is compressed between the first and second transparent electrodes. Methods of operating an elastomeric optical device are also provided.

First claim

What is claimed is:

1. An elastomeric optical device, the elastomeric optical device having a first optical state and a second optical state, the elastomeric optical device being transparent when in the first optical state and being translucent or opaque when in the second optical state, the elastomeric optical device comprising, in sequence, a first transparent electrode, a dielectric layer, an elastomer layer, and a second transparent electrode, the dielectric layer having a greater stiffness than the elastomer layer, the elastomer layer having a Shore OOO hardness of less than 15 and an elastic modulus that is lower than 20 kPa, the second transparent electrode configured to compress the elastomer layer in response to an electric field between the first and second transparent electrodes, such that when the elastomeric optical device is in the second optical state the elastomer layer is compressed between the first and second transparent electrodes.

2. The elastomeric optical device of claim 1 wherein the dielectric layer has an elastic modulus, and a ratio of the elastic modulus of the dielectric layer to the elastic modulus of the elastomer layer is at least 5,000:1.

3. The elastomeric optical device of claim 2 wherein the ratio of the elastic modulus of the dielectric layer to the elastic modulus of the elastomer layer is at least 100,000:1.

4. The elastomeric optical device of claim 1 wherein the elastomer layer has a yield strength of less than 10 kPa.

5. The elastomeric optical device of claim 4 wherein the yield strength is less than 5 kPa.

6. The elastomeric optical device of claim 1 wherein the elastomer layer is formed of material having a dielectric constant in a range of from 2.5 to 3.2.

7. The elastomeric optical device of claim 1 wherein the elastomer layer comprises a silicone gel characterized by being substantially devoid of unreacted sites.

8. The elastomeric optical device of claim 1 wherein the elastomer layer and the dielectric layer each have a thickness in a range of from 1 to 10 microns.

9. The elastomeric optical device of claim 8 wherein the first and second transparent electrodes have a potential difference between them, the potential difference being in a range of from 40 to 350 Volts.

10. The elastomeric optical device of claim 8 wherein the dielectric layer has a thickness, the elastomer layer has a thickness, and a ratio of the thickness of the elastomer layer to the thickness of the dielectric layer is in a range of from 1 to 3.3.

11. The elastomeric optical device of claim 1 wherein at least certain portions of the second transparent electrode are closer to the first transparent electrode when the elastomeric optical device is in the second optical state than they are when the elastomeric optical device is in the first optical state, the elastomeric optical device having a surface topography that is characterized by greater roughness when the elastomeric optical device is in the second optical state than when it is in the first optical state.

12. The elastomeric optical device of claim 11 wherein the surface topography of the elastomeric optical device when in the second optical state is characterized by pits, wrinkles, or both.

13. The elastomeric optical device of claim 12 wherein the surface topography of the elastomeric optical device when in the second optical state includes more than 100,000 pits/cm 2 .

14. The elastomeric optical device of claim 1 wherein the elastomer layer and the dielectric layer together provide a desired level of electrical conductivity between the first transparent electrode and the second transparent electrode, the desired level of electrical conductivity being in a range of from 10 −15 to 10 −7 S/cm.

15. The elastomeric optical device of claim 1 wherein the first transparent electrode is a cathode and the second transparent electrode is an anode.

16. The elastomeric optical device of claim 15 wherein the first transparent electrode comprises a transparent conductive oxide film.

17. The elastomeric optical device of claim 16 wherein the transparent conductive oxide film comprises indium tin oxide.

18. The elastomeric optical device of claim 1 wherein the dielectric layer has a dielectric strength of 160 V/micron or higher.

19. The elastomeric optical device of claim 18 wherein the dielectric layer has a dielectric constant in a range of from 3 to 5, and a Shore A hardness of greater than 65.

20. The elastomeric optical device of claim 1 having a capacitance of less than 200 pF per square inch.

21. The elastomeric optical device of claim 1 further comprising a glass pane, wherein the glass pane supports the first transparent electrode, the dielectric layer, the elastomer layer, and the second transparent electrode.

22. The elastomeric optical device of claim 21 further comprising a polymer substrate, wherein the polymer substrate is mounted to the glass pane and carries the first transparent electrode, the dielectric layer, the elastomer layer, and the second transparent electrode.

23. The elastomeric optical device of claim 21 wherein the glass pane is part of a multi-pane insulating glazing unit having a between-pane space, the elastomeric optical device being exposed to the between-pane space.

24. The elastomeric optical device of claim 23 wherein the multi-pane insulating glazing unit further includes a low-emissivity coating on a #2 surface of the multi-pane insulating glazing unit, and the elastomeric optical device is located further from a #1 surface of the multi-pane insulating glazing unit than is the low-emissivity coating such that solar radiation passing into the multi-pane insulating glazing unit through the #1 surface reaches the low-emissivity coating before reaching the elastomeric optical device, the multi-pane insulating glazing unit being mounted in a position such that the #1 surface is exposed to an outdoor environment.

25. An elastomeric optical device, the elastomeric optical device having a first optical state and a second optical state, the elastomeric optical device being transparent when in the first optical state and being translucent or opaque when in the second optical state, the elastomeric optical device comprising, in sequence, a first transparent electrode, a dielectric layer having an elastic modulus, an elastomer layer having an elastic modulus, and a second transparent electrode, wherein a ratio of the elastic modulus of the dielectric layer to the elastic modulus of the elastomer layer is at least 5,000:1, the elastomer layer and the dielectric layer each having a thickness in a range of from 1 to 10 microns, the second transparent electrode configured to compress the elastomer layer in response to an electric field between the first and second transparent electrodes, such that when the elastomeric optical device is in the second optical state the elastomer layer is compressed between the first and second transparent electrodes, and the elastomeric optical device transitions from the first optical state to the second optical state in response to an activation voltage, the activation voltage being in a range of from 100 to 250 Volts.

26. The elastomeric optical device of claim 25 wherein the ratio of the elastic modulus of the dielectric layer to the elastic modulus of the elastomer layer is at least 100,000:1.

27. The elastomeric optical device of claim 25 wherein elastom

Assignees

• Cardinal Cg Co

Inventors

• Chowdhury Reaz Ahmed
• Arellano Luis Octavio
• Burrows Keith James

Classifications

• E06B2009/2464

  featuring transparency control by applying voltage, e.g. LCD, electrochromic panels · CPC title

• E06B2009/247

  Electrically powered illumination · CPC title

• E06B3/6722

  with adjustable passage of light · CPC title

• E06B9/24

  Screens or other constructions affording protection against light, especially against sunshine; Similar screens for privacy or appearance; {Slat blinds}(operating, guiding or securing devices or arrangements for roll-type closures E06B9/56; free-hanging flexible screens A47H23/00) · CPC title

• E06B2009/2417

  Light path control; means to control reflection · CPC title