Patent US4298250A successfully refreshed from Google Patents.
US4298250A
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US
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Solid electrochromic devices
Assignee: AT&T Inc
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Filing: 1978-10-31
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Granted: 1981-11-03
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Expires: 1998-10-31
Abstract
Abstract Solid state electrochromic devices are fabricated using, as the electrochromic material, ionic conductors such as heteropoly acids. The properties of the ionic conductors permit construction of a device having only two electrodes and the electrochromic material. In operation, low voltages impressed between the electrodes induce a color change. For example, when phosphotungstic acid is employed, the color change is from white to dark blue. Cycle times as low as 100 msec are achievable and the devices exhibit memory properties.
Inventors
- 👤 Gary D. Boyd
- 👤 Sarat K. Mohapatra
- 👤 Benjamin Tell
- 👤 Sigurd Wagner
- 👤 Fred Wudl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:33
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/15; G02F1/1514; G02F1/1523; G02F1/1524
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
147 words
A device comprising, (1) a solid electrochromic material, (2) a first and second electrode, said electrodes being in intimate contact with said electrochromic material and having means for applying an electric potential between said electrodes, (3) means for making electromagnetic radiation incident on said electrochromic material, and (4) means for observing an optical modification in said electrochromic material resulting from imposition of said electric potential CHARACTERIZED IN THAT said solid electrochromic material, (1) has a charge carrier from group I of the Mendelevian periodic table, (2) has an electronic transference number at room temperature less than 10 -3 , (3) has a resistivity less than 2×10 4 ohm-cm, (4) has a chemically bound constituent which undergoes an electrically induced coloration, and (5) comprises a polyhetero acid; whereby when a potential is applied between said first and second electrode an optical change is produced in said electrochromic material.
Claim 2
Independent Claim
147 words
A device comprising, (1) a solid electrochromic material, (2) a first and second electrode, said electrodes being in intimate contact with said electrochromic material and having means for applying an electric potential between said electrodes, (3) means for making electromagnetic radiation incident on said electrochromic material, and (4) means for observing an optical modification in said electrochromic material resulting from imposition of said electric potential CHARACTERIZED IN THAT said solid electrochromic material, (1) has a charge carrier from group I of the Mendelevian periodic table, (2) has an electronic transference number at room temperature less than 10 -3 , (3) has a resistivity less than 2×10 4 ohm-cm, (4) has a chemically bound constituent which undergoes an electrically induced coloration, and (5) comprises a polyhetero acid; whereby when a potential is applied between said first and second electrode an optical change is produced in said electrochromic material.
Claim 3
Dependent Claim
23 words
The device of claim 1 wherein said electrochromic material comprises a polyphosphoric acid chosen from the group consisting of polyphosphotungstic and polyphosphomolybdic acids.
Claim 4
Dependent Claim
13 words
The device of claim 1 wherein said first electrode is SnO 2 .
Claim 5
Dependent Claim
27 words
The device of claim 1 wherein said second electrode contains a mobile species derived from a member of the group consisting of Cu, Ag, Li and H.
Claim 6
Dependent Claim
15 words
The device of claim 1 wherein said electrochromic material is compressed onto said first electrode.
Claim 7
Dependent Claim
11 words
The device of claim 1 wherein said second electrode is carbon.
Claim 8
Dependent Claim
21 words
The device of claim 1 wherein the means for applying an electric potential to said second electrode is a carbon rod.
Claim 9
Dependent Claim
26 words
The device of claim 1 wherein said solid electrochromic material contains a bound species derived from a member of the group consisting of tungsten and molybdenum.
Claim 10
Dependent Claim
22 words
The device of claim 1 wherein said means for making electromagnetic radiation incident on said electrochromic material is a transparent first electrode.
Claim 11
Dependent Claim
22 words
The device of claim 1 wherein said means for observing an optical modification in said electrochromic material is a transparent first electrode.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |