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US4780643A
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Semiconductor electrodes having multicolor luminescence
Assignee: 3M Co
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Filing: 1983-03-30
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Granted: 1988-10-25
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Expires: 2003-03-30
Abstract
Abstract A multicolor luminescent article comprises a layer of a first luminescent semiconductor having a discontinuous layer, pattern or image comprised of a second luminescent semiconductor on at least one surface thereof.
Inventors
- 👤 Arthur B. Ellis
- 👤 Michael K. Carpenter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:07
CPC Classifications
H; H05; H05B; H05B33/00; H05B33/12; H05B33/14; H05B33/145
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
88 words
A luminescent article comprising a semiconductor layer selected from the group consisting of an electroluminescent and photoluminescent semiconductor layer, the composition of which layer consists essentially of a mixture of cadmium sulfide and cadmium selenide, there being a graded change in the composition of said layer such that the concentration of cadium sulfide increases when moving from one surface of said layer to the other surface of said layer, said layer exposing different depths of the composition of said layer to provide different visible color emissions upon stimulation.
Claim 2
Dependent Claim
88 words
A luminescent article comprising a semiconductor layer selected from the group consisting of an electroluminescent and photoluminescent semiconductor layer, the composition of which layer consists essentially of a mixture of cadmium sulfide and cadmium selenide, there being a graded change in the composition of said layer such that the concentration of cadium sulfide increases when moving from one surface of said layer to the other surface of said layer, said layer exposing different depths of the composition of said layer to provide different visible color emissions upon stimulation.
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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) | 1991-10-25 | 1992-04-25 | 1992-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-25 | 1996-04-25 | 1996-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-25 | 2000-04-25 | 2000-10-25 | $7700.00 | Window Closed / Lapsed |