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US4877995A
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Electroluminescent display device using hydrogenated and carbonated amorphous silicon
Assignee: Ministère des Postes Télégraphes et Téléphones
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Filing: 1987-10-19
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Granted: 1989-10-31
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Expires: 2007-10-19
Abstract
Abstract An electroluminescent display device uses a photoconductive material which is of hydrogenrated and carbonated amorphous silicon of formula a-Si x C 1-x ; with 1-x preferably between 0.05 and 0.50 and which has application to display functions.
Inventors
- 👤 Pascal Thioulouse
- 👤 Ionel Solomon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:28
CPC Classifications
H; H05; H05B; H05B33/00; H05B33/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
81 words
Electroluminescent display device comprising on an insulating support (10) an electroluminescent layer (16) and a photoconductive layer (20), said layers being stacked on one another, the two layers being inserted between two systems of electrodes (12,22) connected to a voltage supply source (24) permitting the excitation of certain zones of the electroluminescent layer, said device being characterized in that the photoconductive layer is of hydrogenated and carbonated amorphous silicon a-Si x C 1-x :H, wherein 1-x is between 0.05 and 0.50.
Claim 2
Dependent Claim
81 words
Electroluminescent display device comprising on an insulating support (10) an electroluminescent layer (16) and a photoconductive layer (20), said layers being stacked on one another, the two layers being inserted between two systems of electrodes (12,22) connected to a voltage supply source (24) permitting the excitation of certain zones of the electroluminescent layer, said device being characterized in that the photoconductive layer is of hydrogenated and carbonated amorphous silicon a-Si x C 1-x :H, wherein 1-x is between 0.05 and 0.50.
Claim 3
Dependent Claim
15 words
Display device according to claim 1, characterized in that 1-x is between 0.10 and 0.35.
Claim 4
Dependent Claim
28 words
Display device according to claim 2, characterized in that the thickness of the photoconductive layer is below 2 microns and that the device has a PC-EL memory effect.
Claim 5
Dependent Claim
46 words
Display device according to claim 1, characterized in that 1-x chosen in one of the following ranges 0.05 to 0.15, 0.10 to 0.35 and 0.25 to 0.50, the sensitivity spectrum of the photoconductive layer then being adapted to the light spectrum emitted by the electroluminescent layer.
Claim 6
Dependent Claim
15 words
Display device according to claim 1, characterized in that 1-x is between 0.20 to 0.50.
Claim 7
Dependent Claim
28 words
Display device according to claim 5, characterized in that 1-x is also chosen in such a way that the resistivity of the photoconductive layer exceeds 10 10 Ω.cm.
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) | 1992-10-30 | 1993-05-01 | 1993-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-30 | 1997-05-01 | 1997-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-30 | 2001-05-01 | 2001-10-31 | $7700.00 | Window Closed / Lapsed |