Variable transmittance optical filter and uses thereof

• US 8,441,707 B2
• Filed: 06/10/2010
• Issued: 05/14/2013
• 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., Spantulescu, Andreea
• Primary Examiner(s): Jones, James
• Application Number:
  US12/813,419
• Publication Number:
  US 20100315693A1
• Time in Patent Office: 1,069 Days
• Field of Search: 359/241
• US Class Current: 359/241
• 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. An optical filter 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, comprising:

a) a first and second substantially transparent substrate;

b) a first and second electrode disposed on the surface of at least one of said substrates;

c) a switching material disposed between said first and second substrates and in contact with said first and second electrodes, said switching material comprising one or more chromophores having both electrochromic and photochromic properties, wherein said one or more chromophores is a diarylethene; and

d) an electrical connection means for electrically connecting said first electrode and said second electrode to a source of electric voltage.

2. The optical filter of claim 1, wherein at least one of said substrates is rigid.

3. The optical filter of claim 1, wherein at least one of said substrates is flexible.

4. The optical filter of claim 1, wherein transitioning is controllable by application of the electric voltage.

5. The optical filter of claim 4, wherein the application of said electric voltage lightens said optical filter during UV exposure.

6. The optical filter of claim 1, wherein said optical filter is capable of achieving a visible light transmittance of about 50% or greater in said light state.

7. The optical filter of claim 1, wherein said optical filter is capable of achieving a visible light transmittance of about 30% or less in said dark state.

8. The optical filter of claim 1, wherein said optical filter is capable of achieving a contrast ratio of greater than about 2.

9. The optical filter of claim 1, wherein said optical filter is capable of transitioning between said light state and said dark state at a rate of between about 1 second and 30 minutes.

10. The optical filter of claim 1, wherein said optical filter is capable of transitioning from said dark state to said light state with application of at least 0.1 Volts.

11. The optical filter of claim 1, wherein said transparent substrates have a sheet resistance of up to about 10,000,000 Ohms/square.

12. The optical filter of claim 1, wherein said optical filter is capable of transitioning from said light state to said dark state with exposure to UV radiation at wavelengths above about 365 nm.

13. The optical filter of claim 1, wherein said diarylethene has the general structure of Formula 1:

14. The optical filter of claim 1, further comprising a UV light blocker capable of blocking UV light at wavelengths of less than 365 nm.

18. A method of using the optical filter of claim 1 in an optical device comprising operatively associating the filter with at least one surface of the device.

20. A variable transmittance window 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, comprising:

a) a substantially transparent window substrate; and

b) at least one optical filter of claim 1 associated with at least one surface of said substrate.

22. An ophthalmic device 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, comprising:

a) a substantially transparent ophthalmic substrate; and

b) an optical filter of claim 1 associated with a surface of said substrate.

15. A method for preparing an optical filter 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, comprising the steps of:

a) disposing a layer of a switching material comprising a diarylethene, having both electrochromic and photochromic properties, between a first and second substantially transparent substrate wherein a first and second electrode is disposed on a surface of at least one of said substrates such that said switching material is in contact with each electrode; and

b) providing an electrical connecting means for connecting said electrodes to a source of electric voltage.

16. The method of claim 15, further comprising curing said switching material to increase the viscosity of said switching material.

17. A switching material comprising one or more chromophores having both electrochromic and photochromic properties and a solvent, wherein said switching material is 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, wherein said one or more chromophores is a diarylethene.

19. A variable transmittance window 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, comprising:

a) a first and second substantially transparent substrate;

b) a first and second electrode disposed on the surface of at least one of said substrates;

c) a switching material disposed between said first and second substrates and in contact with said first and second electrodes, said switching material comprising one or more chromophores having both electrochromic and photochromic properties, wherein said one or more chromophores is a diarylethene; and

d) an electrical connection means for electrically connecting said first electrode and said second electrode to a source of electric voltage.

21. An ophthalmic device 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, comprising:

a) a first and second substantially transparent substrate;

b) a first and second electrode disposed on the surface of at least one of said substrates;

c) a switching material disposed between said first and second substrates and in contact with said first and second electrodes, said switching material comprising one or more chromophores having both electrochromic and photochromic properties, wherein said one or more chromophores is a diarylethene; and

d) an electrical connection means for electrically connecting said first electrode and said second electrode to a source of electric voltage.