Optical: systems and elements – Optical modulator – Light wave temporal modulation
Patent
1992-03-12
1993-12-28
Sugarman, Scott J.
Optical: systems and elements
Optical modulator
Light wave temporal modulation
359265, 252586, 2041921, G02F 101, G02B 523
Patent
active
052744930
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to electrochromic elements, and more particularly to laminated electrochromic glass devices and processes for making such devices.
Electrochromic materials generally are materials which change color upon application of electrical current to induce an electrochemical reaction in the material.
Electrochromic devices are known which comprise a laminated structure including an electrolyte ion conducting layer sandwiched between an electrochromic layer and a counter electrode layer, all sandwiched between a pair of conductive electrodes composed of, for example, indium-tin oxide.
Many of the prior art electrochromic elements utilize WO.sub.3 as the electrochromic color-forming layer. It is known that WO.sub.3 changes from a clear, transparent state to a colored state upon undergoing the reaction: ##STR1## wherein Z is selected from H or alkali metals such as Li or Na.
It is also known from the nonaqueous secondary battery art that various other metals will display electrochromic properties when changing from one valence state to another. Specifically, it is known that some transition metals exhibit electrochromic properties when moving between the +2 and +3 valence states and other transition metals exhibit such properties when changing between the +3 and +4 valence states.
Heretofore, the art has had difficulty utilizing the electrochromic properties of WO.sub.3 in combination with the electrochromic properties of these other known transition metal oxides. For example, it is disclosed by U.S. Pat. No. 4,750,816 that "oxidatively color-forming materials suitable as opposing electrodes of reductive color-forming layers comprising WO.sub.3, etc. are not found in inorganic materials." (Column 1, lines 42-45). This is due to several factors, such as the difficulty in discovering oxidative color-forming materials which (1) have a high enough ion exchange capacity; (2) exhibit an adequate transparency or, even better, exhibit color changes complementary to those of WO.sub.3 ; and (3) have a range of working potential compatible with that of the other materials in the electrochromic element.
The term "complementary" color changes, as used herein, means exhibiting opposite color-forming tendencies upon the insertion of an ion. WO.sub.3 colors when an ion is inserted therein and thus materials "complementary" to WO.sub.3 would bleach upon ion insertion. Thus, an electrochromic element utilizing a layer of WO.sub.3 along with a layer of a material having a complementary color change to WO.sub.3 would have two bleached electrochromic layers when an ion was inserted into the complementary layer and two colored layers when an ion was inserted into the WO.sub.3 layer. This would enable an additive color effect to be attained.
Because of the aforementioned difficulties, prior art electrochromic devices tended to utilize either a single electrochromic layer of WO.sub.3 or other electrochromic material to produce the desired electrochromic color change effect, or utilized either an inorganic compound which undergoes little or no color change upon ion insertion and removal or an organic compound as the opposing or counter electrode to the WO.sub.3 layer. The use of a single electrochromic layer of WO.sub.3 or a layer of WO.sub.3 in conjunction with a counter electrode which remains transparent upon ion insertion and removal, suffers from the disadvantage that the difference in the amount of light that is transmitted through the layer in the clear and colored states is limited by the extent of color change of the WO.sub.3 material. In addition, electrochromic devices utilizing an organic electrochromic layer suffer from the disadvantage that these layers are unstable over long periods of time and thus their long term color-forming durability is questionable.
It is an object of the present invention to provide a novel electrochromic element.
It is another object of the present invention to provide a novel electrochromic glass device.
It is another object of the present inv
REFERENCES:
patent: 3451741 (1969-06-01), Manos
patent: 4006966 (1977-02-01), Meyers et al.
patent: 4116546 (1978-09-01), Leibowitz
patent: 4117103 (1978-09-01), Hong
patent: 4193670 (1980-03-01), Giglia et al.
patent: 4278329 (1981-07-01), Matsuhiro et al.
patent: 4303748 (1981-12-01), Armand et al.
patent: 4312929 (1982-01-01), Randin
patent: 4338000 (1982-07-01), Kamimori et al.
patent: 4357401 (1982-11-01), Andre et al.
patent: 4435048 (1984-03-01), Kamimori et al.
patent: 4448493 (1984-05-01), Matsudaira et al.
patent: 4449790 (1984-05-01), Thoni
patent: 4464447 (1984-08-01), Lazzari et al.
patent: 4471037 (1984-09-01), Bannister
patent: 4497726 (1985-02-01), Brule et al.
patent: 4498739 (1985-02-01), Itaya et al.
patent: 4505997 (1985-03-01), Armand et al.
patent: 4573768 (1986-03-01), Polak et al.
patent: 4578326 (1986-03-01), Armand et al.
patent: 4585312 (1986-04-01), Ishiwata et al.
patent: 4620944 (1986-11-01), Armand et al.
patent: 4638407 (1987-01-01), Lundsgaard
patent: 4654279 (1987-03-01), Bauer et al.
patent: 4664934 (1987-05-01), Ito et al.
patent: 4671619 (1987-06-01), Kamimori et al.
patent: 4690840 (1987-09-01), Gauthier et al.
patent: 4712879 (1987-12-01), Lynam et al.
patent: 4722877 (1988-02-01), Sammells
patent: 4749260 (1988-06-01), Yang et al.
patent: 4750816 (1988-06-01), Ito et al.
patent: 4750817 (1988-06-01), Sammells
patent: 4752544 (1988-06-01), Gregory
patent: 4758483 (1988-07-01), Armand et al.
patent: 4798773 (1989-01-01), Yasukawa et al.
patent: 4801195 (1989-01-01), Kawai et al.
patent: 4807977 (1989-02-01), Sammells
patent: 4828369 (1989-05-01), Hotomi
patent: 4851307 (1989-07-01), Armand et al.
patent: 4867541 (1989-09-01), Hotomi
patent: 4878743 (1989-11-01), Aikawa et al.
patent: 4882243 (1989-11-01), Skotheim et al.
patent: 4908283 (1990-03-01), Takahashi et al.
patent: 4911995 (1990-03-01), Belanger et al.
patent: 4938571 (1990-07-01), Cogan et al.
patent: 5086351 (1992-02-01), Couput et al.
Ronald B. Goldner, Electrochromic Materials for Controlled Radiant Energy Transfer in Buildings, pp. 38-44. (No Date).
Svensson et al., No Visible Electrochromism in High-Quality E-Beam Evaporated In203:Sn Films, Aug. 1, 1985, pp. 2284-2285.
Cogan et al., Materials and Devices in Electrochromic Window Development, pp. 23-31 (1985).
Lampert, Electrochromic Materials and Devices for Energy Efficient Windows, pp. 1-27 (1984).
Schuster et al., Solid State Electrochromic Infrared Switchable Windows, pp. 153-160 (1986).
Svensson et al., Electrochromism of Nickel-Based Sputtered Coatings pp. 19-26 (1987).
Babulanam et al., Smart Window Coatings: Some Recent Advances, pp. 64-71 (1987).
Cogan et al., Optical Switching in "Complementary" Electrochromic Windows, pp. 32-38 (1986).
Yu et al., In-Situ Spectroscopic Studies of Electrochromic Hydrated Nickel Oxide Films, pp. 113-123 (1987).
Fantini et al., Electrochromic Nickel Hydroxide Films on Transparent/Conducting Substrates, pp. 487-500 (1987).
Stefan et al., Optical Properties of Electrochromic Hydrated Nickel Oxide Coatings Made by rf Sputtering, pp. 1554-1556 (1987).
Emrich et al., Surface Analysis of Electrochromic Displays of Iron Hexacyanoferrate Films by X-Ray Photoelectron Spectroscopy, pp. 1307-1310 (1987).
"Ion Conductivity of Poly(ethylene oxide)-based Polyurethane Networks Containing Alkali Metal Salts", Tada et al., Jour. of Polymer Science Part A: Polymer Chemistry, vol. 25, pp. 3015-3024 (1987).
"Rilevatori Termoelettrocromici A Stato Solido", Bonino et al., La Chimica E L'Industria, V. 69, N. 718 (1987).
"Electrochromism And Electrochromic Devices", Scrosati, Chimicaoggi, Jun. 1989.
"An Electrochromic Window Based on Li.sub.x WO.sub.3 /(PEO).sub.8 LiClO.sub.4 /NiO", Passerini et al., J. Electrochem. Society, vol. 136, No. 11, Nov. 1989.
Rauh et al., "Materials for Electrochromic Windows", SPIE, vol. 502, Optical Materials Technology for Energy Efficiency and Solar Energy Conversion III, pp. 38-45 (1984).
Tada et al., "Electrochromic Windows Using a Solid Polymer Electro
Bourrel Maurice
Campet Guy
Chabagno Jean M.
Couput Jean-Paul
Delmas Claude
Elf Atochem North America Inc.
Lester Evelyn A.
Societe Nationale Elf Aquitaine
Sugarman Scott J.
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