US4167308A
Expired / Lapsed
US
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Electrochromic display device
Assignee: International Business Machines Corp
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Filing: 1978-02-13
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Granted: 1979-09-11
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Expires: 1998-02-13
Abstract
Abstract An electrochromic display device has an improved counter electrode arrangement. The device has a plurality of display elctrodes and a counter electrode in contact with a first electrolyte of a primary redox system. The counter electrode is charged to a predetermined potential. A secondary redox system is associated with the primary redox system. A secondary electrode in the secondary redox system is electrically connected to the counter electrode to maintain the charge on the counter electrode at a predetermined potential.
Inventors
- 👤 Donald J. Barclay
- 👤 Colin L. Bird
- 👤 Anthony C. Lowe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:14
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/15; G02F1/163; G02F1/1503
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
98 words
An electrochromic display device comprising: a first redox system containing a first electrolyte, a counter electrode in contact with said first electrolyte, said counter electrode containing a material that undergoes a reversible redox reaction in said first electrolyte at a known potential, a plurality of display electrodes in contact with said first electrolyte, a second redox system separated from said first redox system by an ion exchange membrane, and a third electrode in said second redox system and being electrically connected to said counter electrode wherein the charge of said counter electrode is maintained at said known potential.
Claim 2
Dependent Claim
98 words
An electrochromic display device comprising: a first redox system containing a first electrolyte, a counter electrode in contact with said first electrolyte, said counter electrode containing a material that undergoes a reversible redox reaction in said first electrolyte at a known potential, a plurality of display electrodes in contact with said first electrolyte, a second redox system separated from said first redox system by an ion exchange membrane, and a third electrode in said second redox system and being electrically connected to said counter electrode wherein the charge of said counter electrode is maintained at said known potential.
Claim 3
Dependent Claim
28 words
A device as described in claim 1 wherein said second redox system includes a second electrolyte that is separated from said first electrolyte by an ion exchange member.
Claim 4
Dependent Claim
18 words
A device as described in claim 2, wherein the first electrolyte includes as active ingredient heptyl viologen dications.
Claim 5
Dependent Claim
34 words
A device as described in claim 2 or claim 3, wherein the secondary redox system includes a redox couple selected from the group consisting of Cd/Cd II , In/In III and Sn/Sn II .
References Cited (Backward Citations)
US3453038A
Cited
US3712709A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-09-10 | 1983-03-12 | 1983-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-10 | 1987-03-12 | 1987-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-10 | 1991-03-12 | 1991-09-11 | $7700.00 | Window Closed / Lapsed |