US4486499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroluminescent device
Assignee: Futaba Corp
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Filing: 1981-06-05
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Granted: 1984-12-04
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Expires: 2001-06-05
Abstract
Abstract The electroluminescent device comprises an electroluminescent layer and means for exciting the electroluminescent layer to luminescence with an electric field. The electroluminescent layer comprises a phosphor layer having characteristics of a n-type semiconductor and a semiconductor layer consisting of copper sulfide having characteristics of a p-type semiconductor.
Inventors
- 👤 Kiyoshi Morimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:10
CPC Classifications
H; H05; H05B; H05B33/00; H05B33/12; H05B33/14; H05B33/145; H10; H10H; H10H20/00; H10H20/80; H10H20/81; Y; Y10; Y10S; Y10S428/00; Y10S428/917; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
79 words
An electroluminescent device comprising: a transparent glass substrate; a transparent electrode deposited on said transparent glass substrate; a phosphor layer about 0.1 to about 10 μm thick having characteristics of an n-type semiconductor deposited on said transparent electrode, said layer comprising an n-type dopant in sufficient concentrations to provide said n-type characteristic; a semiconductor layer consisting of copper sulfide having characteristics of a p-type semiconductor deposited on said phosphor layer; and a back electrode deposited on said semiconductor layer.
Claim 2
Dependent Claim
79 words
An electroluminescent device comprising: a transparent glass substrate; a transparent electrode deposited on said transparent glass substrate; a phosphor layer about 0.1 to about 10 μm thick having characteristics of an n-type semiconductor deposited on said transparent electrode, said layer comprising an n-type dopant in sufficient concentrations to provide said n-type characteristic; a semiconductor layer consisting of copper sulfide having characteristics of a p-type semiconductor deposited on said phosphor layer; and a back electrode deposited on said semiconductor layer.
Claim 3
Dependent Claim
23 words
The electroluminescent device defined in claim 1 wherein said phosphor layer comprises a phosphor which is processed to be low in electric resistance.
Claim 4
Dependent Claim
33 words
The electroluminescent device defined in claim 1 or 2 wherein said phosphor layer comprises one or more phosphors in which impurities acting as a donor within the host fluorescent material are heavily doped.
Claim 5
Dependent Claim
20 words
An electroluminescent device according to claim 1 or 2 wherein said device is driven by a low voltage DC source.
Claim 6
Dependent Claim
14 words
An electroluminescent device according to claim 4 wherein said device is stable in operation.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-04 | 1988-06-04 | 1988-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-04 | 1992-06-04 | 1992-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-04 | 1996-06-04 | 1996-12-04 | $7700.00 | Window Closed / Lapsed |