Variable transmittance optical filter and uses thereof

• US 9,864,252 B2
• Filed: 11/16/2015
• Issued: 01/09/2018
• Est. Priority Date: 06/11/2009
• Status: Active Grant

• Current Assignee: Solutia Canada, Inc. (Eastman Chemical Company)
• Original Assignee: Switch Materials, Inc.
• Inventors: Lam, Duhane, Branda, Neil R.
• Primary Examiner(s): Jones, James
• Application Number:
  US14/942,119
• Publication Number:
  US 20160077400A1
• Time in Patent Office: 785 Days
• Field of Search: 359241
• CPC Class Codes: B60J 3/04 adjustable in transparency
• CPC Class Codes: E06B 9/24 Screens or other constructions affording protection against light, especially against sunshine; Similar screens for privacy or appearance; Slat blindsoperating, guiding or securing devices or arrangements for roll-type closures E06B9/56; free-hanging flexible screens A47H23/00
• CPC Class Codes: G02B 5/223 containing organic substances, e.g. dyes, inks or pigments
• CPC Class Codes: G02B 5/23 Photochromic filters
• CPC Class Codes: G02C 7/101 having an electro-optical light valve electro-optical elements per se G02F
• CPC Class Codes: G02C 7/102 Photochromic filters
• CPC Class Codes: G02F 1/0018 Electro-optical materials
• CPC Class Codes: G02F 1/0063 Optical properties, e.g. absorption, reflection or birefringence materials for non-linear optics G02F1/355
• CPC Class Codes: G02F 1/15165 Polymers
• CPC Class Codes: G02F 1/1533 structural features not otherwise provided for
• CPC Class Codes: G02F 1/157 Structural association of cells with optical devices, e.g. reflectors or illuminating devices
• CPC Class Codes: G02F 1/163 Operation of electrochromic cells, e.g. electrodeposition cells; Circuit arrangements therefor
• CPC Class Codes: G02F 2201/086 UV absorbing
• CPC Class Codes: H01R 43/26 for engaging or disengaging the two parts of a coupling device structural association with two-part coupling device H01R13/629
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49204 Contact or terminal manufacturing

Abstract

Variable transmittance optical filters capable of transitioning from a light state to a dark state on exposure to UV radiation and from a dark state to a light state with application of an electric voltage are provided. The optical filters comprise a switching material that comprises one or more chromophores that have electrochromic and photochromic properties.

Claims

1. A variable tint window, comprising:

(a) at least one sheet of transparent substrate;

(b) a variable transmittance optical filter comprising a first and a second electrode and a switching material in contact with the first and second electrodes and disposed on the at least one sheet of transparent substrate, wherein the switching material transitions from a light state to a dark state on exposure to ultraviolet radiation and absent application of an electric voltage required to trigger lightening from the dark state across the first and second electrodes and from the dark state to the light state with application of the voltage across the first and second electrodes, and wherein a visible light transmittance of the optical filter is lower when in the dark state than when in the light state; and

(c) power control electronics comprising a switch for electrically coupling to a power source, the power control electronics electrically coupled to the first and second electrodes and operable to transition the variable transmittance optical filter from the dark state to the light state by applying the voltage from the power source across the first and second electrodes, wherein the switch in the power control electronics comprises a multi-state control device operable to permit a user to select an intermediate transmittance for the optical filter, wherein the power control electronics applies the voltage across the first and second electrodes for a duration sufficient to achieve the intermediate state.

2. The variable tint window of claim 1 wherein the variable tint window comprises a window of a vehicle.

3. The variable tint window of claim 1 wherein the variable transmittance optical filter is laminated to the at least one sheet of transparent substrate.

4. The variable tint window of claim 3 further comprising a second sheet of transparent substrate laminated on the other side of the variable transmittance optical filter from the at least one sheet of transparent substrate.

5. The variable tint window of claim 1 wherein the switching material comprises a hybrid photo/electro dye that is organic.

6. The variable tint window of claim 1 wherein the window comprises a sunroof, side window, rear window, or a portion of the windshield of an automobile.

7. The variable tint window of claim 1 further comprising a frame into which at least one sheet of transparent substrate is mounted, the frame forming a window designed to be installed in a vehicle.

8. The variable tint window of claim 1 with a contrast ratio of about three or greater.

9. The variable tint window of claim 1 further comprising an IR reflective coating.

10. The variable tint window of claim 1 wherein the switching material scatters light such that the haze of the variable transmittance optical filter is about 5% or less in both the dark and light states.

11. The variable tint window of claim 1 wherein the switching material is in contact with a surface of the at least one sheet of transparent substrate.

12. The variable tint window of claim 1 wherein the switching material is not in contact with a surface of the at least one sheet of transparent substrate.

13. A variable tint window, comprising:

(a) at least one sheet of transparent substrate;

(b) a variable transmittance optical filter comprising a first and a second electrode and a switching material in contact with the first and second electrodes and disposed on the at least one sheet of transparent substrate, wherein the switching material transitions from a light state to a dark state on exposure to ultraviolet radiation and absent application of an electric voltage required to trigger lightening from the dark state across the first and second electrodes and from the dark state to the light state with application of the voltage across the first and second electrodes, and wherein a visible light transmittance of the optical filter is lower when in the dark state than when in the light state; and

(c) power control electronics comprising a switch for electrically coupling to a power source, the power control electronics electrically coupled to the first and second electrodes and operable to transition the variable transmittance optical filter from the dark state to the light state by applying the voltage from the power source across the first and second electrodes, wherein the switch comprises a multi-state control device operable to permit a user to select an intermediate transmittance for the optical filter, wherein the power control electronics apply the voltage across the first and second electrodes to achieve the intermediate state based on feedback from one or more light sensors.

14. The variable tint window of claim 13 wherein the variable tint window comprises a window of a vehicle.

15. The variable tint window of claim 13 wherein the variable transmittance optical filter is laminated to the at least one sheet of transparent substrate.

16. The variable tint window of claim 15 further comprising a second sheet of transparent substrate laminated on the other side of the variable transmittance optical filter from the at least one sheet of transparent substrate.

17. The variable tint window of claim 13 wherein the switching material comprises a hybrid photo/electro dye that is organic.

18. The variable tint window of claim 13 further comprising a frame into which at least one sheet of transparent substrate is mounted, the frame forming a window designed to be installed in a vehicle.

19. The variable tint window of claim 13 wherein the switching material scatters light such that the haze of the variable transmittance optical filter is about 5% or less in both the dark and light states.

20. A variable tint window, comprising:

(a) at least one sheet of transparent substrate;

(b) a variable transmittance optical filter comprising a first and a second electrode and a switching material in contact with the first and second electrodes and disposed on the at least one sheet of transparent substrate, wherein the switching material transitions from a light state to a dark state on exposure to ultraviolet radiation and absent application of an electric voltage required to trigger lightening from the dark state across the first and second electrodes and from the dark state to the light state with application of the voltage across the first and second electrodes, and wherein a visible light transmittance of the optical filter is lower when in the dark state than when in the light state; and

(c) power control electronics comprising a switch for electrically coupling to a power source, the power control electronics electrically coupled to the first and second electrodes and operable to transition the variable transmittance optical filter from the dark state to the light state by applying the voltage from the power source across the first and second electrodes, wherein the switch comprises a multi-state control device operable to permit a user to select an intermediate transmittance for the optical filter, wherein the power control electronics apply the voltage across the first and second electrodes to achieve the intermediate state based on feedback from one or more light sensors, wherein the power control electronics further comprise a voltage or a current sensor that senses when the switching material has transitioned to the light state, and wherein the power control electronics cease to apply the voltage across the first and second electrodes when the switching material has transitioned to the light state.