Solid state electrochromic light modulator

• US RE34,469 E
• Filed: 11/19/1990
• Issued: 12/07/1993
• Est. Priority Date: 06/18/1987
• Status: Expired due to Term

• Current Assignee: EIC Laboratories, Inc.
• Original Assignee: EIC Laboratories, Inc.
• Inventors: Cogan, Stuart F., Rauh, R. David
• Primary Examiner(s): Hille, Rolf
• Assistant Examiner(s): SAADAT, MAHSHID D
• Application Number:
  US07/615,037
• Time in Patent Office: 1,114 Days
• Field of Search: 350/357, 359/269, 359/267, 359/275
• US Class Current: 359/269
• CPC Class Codes: G02F 1/1523 comprising inorganic material
• CPC Class Codes: G02F 2001/1555 Counter electrode

Abstract

An all solid-state variable transmission electrochromic device has a source of charge compensating ions. An inorganic oxide counterelectrode film which on reduction with the accompanying insertion of the charge compensating ions increases its transmission of light of predetermined wavelength is separated from a primary electrochromic film which on reduction with the accompanying insertion of the charge compensating ions decreases its transmission of light of predetermined wavelength by an insulating electrolyte film that transports the charge compensating ions. First and second electrodes are contiguous with the inorganic oxide counter electrode film and the primary electrochromic film, respectively, and separated by the three films.

Claims

1. A solid-state variable transmission electrochromic device comprising,

a source of charge compensating ions,

an inorganic oxide electrochromic counter electrode film composed of a mixture of at least two oxides with a first of said oxides an oxide of a metal from the group consisting of vanadium and chromium and a second of said oxides an oxide of a different metal from the group consisting of V, Cr, Nb, Ta and Ti which on reduction with the accompanying insertion of said charge compensating ions increases its transmission of light of predetermined wavelength,

a primary electrochromic film which on reduction with the accompanying insertion of said charge compensating ions decreases its transmission of light of said predetermined wavelength,

an insulating electrolyte film contiguous with and separating said inorganic oxide counter electrode film and said primary electrochromic film for the transport of said charge compensating ions therebetween,

first and second electrodes contiguous with said inorganic oxide counter electrode film and said primary electrochromic film respectively and separated by said inorganic oxide counter electrode film, said insulating electrolyte film and said primary electrochromic film,

said first and second electrodes being for receiving an electric potential therebetween for producing a current flow such that electrons flow into one of said electrodes and out of the other and said charge compensating ions flow through said insulating electrolyte film from that one of said inorganic oxide counter electrode and said primary electrochromic film being oxidized to that one thereof being reduced for modulating said device between states of minimum and maximum transmission at said predetermined wavelength with the direction of transmission change being determined by the direction of current flow.

2. The device of claim 1 wherein one of said electrodes is a thin film transmissive at said predetermined wavelength and the other of said electrodes is reflective at said predetermined wavelength,

wherein the reflectivity of said device may be modulated between a state of maximum reflectivity and a state of minimum reflectivity by controlling the absorption of said device with a potential applied between said first and second electrodes.

3. The device of claim 1 wherein said first and second electrodes are thin films transmissive at said predetermined wavelength,

wherein the transmittance of said device may be controlled between a state of maximum transmittance and a state of minimum transmittance in response to a potential applied between said first and second electrodes.

4. A device in accordance with claim 1 wherein said primary electrochromic film is tungsten trioxide,

said inorganic oxide counter electrode film is a mixture (V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) prereduced with Li,

said insulating electrolyte film is sputtered from a composite target of 42% Li₂ O, 25% SiO₂ and 32% ZrO₂,

said charge compensating ions are lithium,

said first electrode is reflective aluminum, (X═

and said second electrode is transparent and tin-doped indium oxide on a substrate.

5. A device in accordance with claim 2 wherein said primary electrochromic film is tungsten trioxide,

said inorganic oxide counter electrode film is a mixture .[.(V₂ O₅)1-x(Nb₂ O₅)x(x═

0.01-0.99).]. (.Iadd.V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) .Iaddend.prereduced with Li,

said insulating electrolyte film is sputtered from a composite target of 42% Li₂ O, 26% SiO₂ and 32% ZrO₂,

said charge compensating ions are lithium,

said first electrode is reflective aluminum,

and said second electrode is transparent and tin-doped indium oxide on a substrate.

6. A device in accordance with claim 1 wherein said primary electrochromic film is tungsten trioxide.

said inorganic oxide counter electrode film is a mixture (V₂ O₅)_1-x (Nb₂ O₅)_x, X═

0.01-0.99) prereduced with Li,

said insulating electrolyte film is sputtered from a composite target of 42% Li₂ O, 26% SiO₂ and 32% ZrO₂,

said charge compensating ions are lithium,

said first electrode is reflective aluminum,

and said second electrode is transparent and tin-doped indium oxide on a substrate,

wherein the reflectance of said device may be controlled between a state of maximum transmittance and a state of minimum transmittance in response to a potential applied between said first and second electrodes.

7. A device in accordance with claim 1 wherein said first electrode comprises tin-doped indium oxide.

8. A device in accordance with claim 1 wherein said primary electrochromic film is tungsten trioxide,

said counter electrode is a mixture .[.(V₂ O₅)1-x(Nb₂ O₅) x (x═

0.01-0.99).]. (.Iadd.V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) .Iaddend.prereduced with Li,

said insulating electrolyte film is poly (bismethoxyethoxymethoxide) phosphazine doped with LiCF₃ SO₃,

and said first and second electrodes are tin-doped indium oxide deposited upon glass.

9. A device in accordance with claim .[.1.]. .Iadd.3 .Iaddend.wherein said primary electrochromic film is tungsten trioxide,

said counter electrode is a mixture (V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) prereduced with Li,

said insulating electrolyte film is poly(bismethoxyethoxymethoxide) phosphazine doped with LiCF₃ SO₃,

and said first and second electrodes are tin-doped indium oxide deposited upon glass,

.[.wherein one of said electrodes is a thin film transmissive at said predetermined wavelength and the other of said electrodes is reflective at said predetermined wavelength,.].

wherein the .[.reflectivity.]. .Iadd.transmissivity .Iaddend.of said device may be modulated between a state of maximum .[.reflectivity.]. .Iadd.transmissivity .Iaddend.and a state of minimum .[.reflectivity.]. .Iadd.transmissivity .Iaddend.by controlling the .[.adsorption.]. .Iadd.absorption .Iaddend.of said device with a potential applied between said first and second electrodes.

10. A device in accordance with claim 3 wherein said primary electrochromic film is tungsten trioxide,

said counter electrode is a mixture .[.(V₂)₅)1-x(Nb₂ O₅)_x (x═

0.01-0.99).]. (.Iadd.V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) .Iaddend.prereduced with Li,

said insulating electrolyte film is poly (bismethoxyethoxymethoxide) phosphazine doped with LiCF₃ SO₃,

and said first and second electrodes are tin-doped indium oxide deposited upon glass.

11. A device in accordance with claim 1 wherein said primary electrochromic film is tungsten trioxide,

said counter electrode is a mixture .[.(V₂ O₅)1-x(Nb₂ O₅)x (x═

0.01-0.99).]. (.Iadd.V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) .Iaddend.prereduced with Li,

said insulating electrolyte film is poly (bismethoxyethoxymethoxide) phosphazine doped with LiCF₃ SO₃,

and one of said electrodes is tin-doped indium oxide deposited onto glass and the other of said electrodes is a reflective aluminum film on glass.

12. A device in accordance with claim 2 wherein said primary electrochromic film is tungsten trioxide,

said counter electrode is a mixture .[.(V₂ O₅)1-x(Nb₂ O₅)x (x═

0.01-0.99).]. (.Iadd.V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) .Iaddend.prereduced with Li,

said insulating electrolyte film is poly (bismethoxyethoxymethoxide) phosphazine doped with LiCF₃ SO₃,

and one of said electrodes is tin-doped indium oxide deposited onto glass and the other of said electrodes is a reflective aluminum film on glass.

13. A device in accordance with claim 1 wherein said primary electrochromic film is tungsten trioxide,

said counter electrode is a mixture (V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) prereduced with Li,

said insulating electrolyte film is poly(bismethoxyethoxymethoxide) phosphazine doped with LiCF₃ SO₃,

and one of said electrodes is tin-doped indium oxide, deposited onto glass .[.and the other of said electrodes is a reflective aluminum film on glass,.].

wherein the reflectance of said device may be controlled between a state of maximum transmittance and a state of minimum transmittance in response to a potential applied between said first and second electrodes. .Iadd.14. A device in accordance with claim 1 wherein said primary electrochromic film is tungsten trioxide,

said inorganic oxide counter electrode film is a mixture

(V₂ O₅)_1-x (Nb₂ O₅)_x (x═

0.01-0.99) prereduced with Li,

said insulating electrolyte film is sputtered from a composite target of 42% Li₂ O, 26% SiO₂ and 32% ZrO₂,

said charge compensating ions are lithium

said first electrode is reflective aluminum,

said second electrode is transparent tin-doped indium oxide,

one of said first and second electrodes being on a substrate..Iaddend.