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EP0140246A1
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A thin film electroluminescent display device
Assignee: Osram Sylvania Inc
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Filing: 1984-10-11
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Granted: —
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Expires: 2004-10-11
Abstract
Abstract A thin film electroluminescent display device comprising a transparent electrode layer, a segmented electrode layer, an electroluminescent phosphor layer between the electrode layers, and an improved dark field material disposed as a layer between the phosphor and segmented electrode layers. The improved dark field layer is of a composition of a dielectric material, such as the preferred magnesium oxide, and a noble metal, which in the preferred version is gold. These materials comprising the dark field composition may be co-evaporated by an electron beam evaporation or other suitable deposition technique. The composition of dark field material provides for contrast enhancement is non-toxic, and is readily analyzable.
Inventors
- 👤 Martin P. Schrank
- 👤 Murthy S. Ayyagari
- 👤 Dennis B. Shinn
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 15:04
CPC Classifications
H; H05; H05B; H05B33/00; H05B33/12; H05B33/22
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
54 words
An electroluminescent display device comprising a transparent electrode layer, a segmented electrode layer, an electroluminescent phosphor layer disposed between said electrode layers, and a dark field layer of a composition of a dielectric material with a noble metal, said dark field layer being interposed between said electroluminescent phosphor layer and said segmented electrode layer.
Claim 2
Dependent Claim
54 words
An electroluminescent display device comprising a transparent electrode layer, a segmented electrode layer, an electroluminescent phosphor layer disposed between said electrode layers, and a dark field layer of a composition of a dielectric material with a noble metal, said dark field layer being interposed between said electroluminescent phosphor layer and said segmented electrode layer.
Claim 3
Dependent Claim
21 words
An electroluminescent display device as set forth in claim 1 including only-a single transparent dielectric layer adjacent the electroluminescent phosphor layer.
Claim 4
Dependent Claim
25 words
An electroluminescent display device as set forth in claim 1 wherein the dark field layer has a film thickness in the range of 5000-9000 Angstroms.
Claim 5
Dependent Claim
21 words
An electroluminescent display device as set forth in claim 1 wherein the device has a contrast ratio of at least 2:1.
Claim 6
Dependent Claim
26 words
. An electroluminescent display device as set forth in claim 1 wherein the composition of the dark field layer is deposited by co-evaporation from separate sources.
Claim 7
Dependent Claim
16 words
An electroluminescent display device as set forth in claim 1 wherein the noble metal comprises gold.
Claim 8
Dependent Claim
23 words
An electroluminescent display device as set forth in claim 1 wherein said dielectric material of the dark field layer comprises a metal oxide.
Claim 9
Dependent Claim
17 words
An electroluminescent display device as set forth in claim 7 wherein said metal oxide comprises magnesium oxide.
Claim 10
Dependent Claim
22 words
An electroluminescent display device as set forth in claim 1 wherein said dielectric material of the dark field layer comprises silicon dioxide.
Claim 11
Dependent Claim
22 words
An electroluminescent display device as set forth in claim 1 wherein said dielectric material of the dark field layer comprises germanium dioxide.
Claim 12
Dependent Claim
22 words
An electroluminescent display device as set forth in claim 1 wherein said dielectric material of the dark field layer comprises aluminum nitride.
Claim 13
Dependent Claim
31 words
An electroluminescent display device as set forth in claim 1 wherein said dielectric material of the dark field layer is comprised of a metal oxide, a metal nitride or a semiconductor.
References Cited (Backward Citations)
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