US4877994A
Expired / Lapsed
US
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Electroluminescent device and process for producing the same
Assignee: Hitachi Ltd
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Filing: 1988-03-23
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Granted: 1989-10-31
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Expires: 2008-03-23
Abstract
Abstract An electroluminescent device comprising an electroluminescent layer capable of emitting light under application of AC voltage, the electroluminescent layer comprising strontium sulfide as a matrix and containing at least one of halides and sulfides of cerium, europium, thulium, terbium and samarium, and having a lattice constant of not more than 6.04 Å and a half-width value at the (111) face of not more than 0.21 degree has a higher brightness than an electroluminescent device having an electroluminescent layer comprising ZnS as a matrix.
Inventors
- 👤 Moriaki Fuyama
- 👤 Katsumi Tamura
- 👤 Kazuo Taguchi
- 👤 Kenichi Onisawa
- 👤 Akira Sato
- 👤 Kenichi Hashimoto
- 👤 Takahiro Nakayama
- 👤 Yoshio Abe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:09
CPC Classifications
H; H05; H05B; H05B33/00; H05B33/12; H05B33/14; H05B33/145; H05B33/10; H05B33/22; Y; Y10; Y10S; Y10S428/00; Y10S428/917
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
78 words
An electroluminescent device which comprises: transparent electrodes formed on a transparent substrate; a first insulating layer formed on the transparent electrodes; an electroluminescent layer containing strontium sulfide as a matrix and having a lattice constant of not more than 6.07Å and a half-width at the (111) face of not more than 0.21 degree, formed on the first insulating layer; a second insulating layer formed on the electroluminescent layer; and back side electrodes formed on the second insulating layer.
Claim 2
Dependent Claim
78 words
An electroluminescent device which comprises: transparent electrodes formed on a transparent substrate; a first insulating layer formed on the transparent electrodes; an electroluminescent layer containing strontium sulfide as a matrix and having a lattice constant of not more than 6.07Å and a half-width at the (111) face of not more than 0.21 degree, formed on the first insulating layer; a second insulating layer formed on the electroluminescent layer; and back side electrodes formed on the second insulating layer.
Claim 3
Dependent Claim
47 words
An electroluminescent device according to claim 1 wherein the electroluminescent layer comprises strontium sulfide as a matrix and contains at least one of halides and sulfides of cerium, europium, thulium, terbium and samarium, and has good crystallinity so as to increase the brightness of the electroluminescent device.
Claim 4
Dependent Claim
69 words
An electroluminescent device of high brightness, which comprises an electroluminescent layer capable of emitting light under application of AC voltage, the electroluminescent layer comprising strontium sulfide as a matrix and containing at least one of halides and sulfides of cerium, europium, thulium, terbium and samarium, and having a lattice constant of not more than 6.07Å and a halfwidth value at the (111) face of not more than 0.21 degree.
Claim 5
Dependent Claim
69 words
An electroluminescent device of high brightness, which comprises an electroluminescent layer capable of emitting light under application of AC voltage, the electroluminescent layer comprising strontium sulfide as a matrix and containing at least one of halides and sulfides of cerium, europium, thulium, terbium and samarium, and having a lattice constant of not more than 6.07Å and a halfwidth value at the (111) face of not more than 0.21 degree.
Claim 6
Dependent Claim
16 words
An electroluminescent device according to claim 3, wherein the lattice constant is from 6.02 to 6.07Å.
Claim 7
Dependent Claim
35 words
An electroluminescent device according to claim 3, wherein the content of sulfur in the strontium sulfide in the electroluminescent layer is at least 0.66 in terms of a fluorescent X-ray diffraction intensity ratio of I(S)/I(Sr)+I(S).
Claim 8
Dependent Claim
33 words
An electroluminescent device according to claim 3, wherein the electroluminescent layer is formed by electron beam vapor deposition in vacuum of 9×10 -5 to 5×10 -4 Torr in the presence of sulfur vapors.
Claim 9
Dependent Claim
89 words
An electroluminescent device which comprises a transparent substrate, stripe-shaped transparent electrodes, a first insulating layer, an electroluminescent layer capable of emitting light under application of AC voltage, a second insulating layer and stripe-shaped back side electrodes, laid one upon another, the electroluminescent layer comprising strontium sulfide as a matrix and containing at least one of halides and sulfides of cerium, europium, thulium, terbium and samarium, and having a lattice consant of not more than 6.07Å and a half-width value at the (111) face of not more than 0.21 degree.
Claim 10
Dependent Claim
89 words
An electroluminescent device which comprises a transparent substrate, stripe-shaped transparent electrodes, a first insulating layer, an electroluminescent layer capable of emitting light under application of AC voltage, a second insulating layer and stripe-shaped back side electrodes, laid one upon another, the electroluminescent layer comprising strontium sulfide as a matrix and containing at least one of halides and sulfides of cerium, europium, thulium, terbium and samarium, and having a lattice consant of not more than 6.07Å and a half-width value at the (111) face of not more than 0.21 degree.
Claim 11
Dependent Claim
16 words
An electroluminescent device according to claim 7, wherein the lattice constant is from 6.02 to 6.07Å.
Claim 12
Dependent Claim
35 words
An electroluminescent device according to claim 7, wherein the content of sulfur in the strontium sulfide in the electroluminescent layer is at least 0.66 in terms of a fluorescent X-ray diffraction intensity ratio of I(S)/I(Sr)+I(S).
Claim 13
Dependent Claim
33 words
An electroluminescent device according to claim 7, wherein the electroluminescent layer is formed by electron beam vapor deposition in vacuum of 9×10 -5 to 5×10 -4 Torr in the presence of sulfur vapors.
Claim 14
Dependent Claim
20 words
An electroluminescent device according to claim 7, wherein a ZnS layer is provided on each side of the electroluminescent layer.
Claim 15
Dependent Claim
58 words
An electroluminescent device according to claim 7 wherein the transparent electrodes are formed on the substrate, the first insulating layer is formed on the transparent electrodes, the electroluminescent layer is formed on the first insulating layer, the second insulating layer is formed on the electroluminescent layer and the back side electrodes are formed on the second insulating layer.
Claim 16
Dependent Claim
94 words
A process for producing an electroluminescent device comprising an electroluminescent layer containing strontium sulfide as a matrix, which comprises: forming a transparent electrode film on a transparent substrate; patterning the transparent electrode film to form transparent electrodes; forming a first insulating layer on the transparent electrodes; forming the electroluminescent layer on the first insulating layer by electron beam vapor deposition in vacuum of 9×10 -5 to 5×10 -4 Torr in the presence of sulfur vapors; forming a second insulating layer on the electroluminescent layer; and forming back side electrodes on the second insulating layer.
Claim 17
Dependent Claim
94 words
A process for producing an electroluminescent device comprising an electroluminescent layer containing strontium sulfide as a matrix, which comprises: forming a transparent electrode film on a transparent substrate; patterning the transparent electrode film to form transparent electrodes; forming a first insulating layer on the transparent electrodes; forming the electroluminescent layer on the first insulating layer by electron beam vapor deposition in vacuum of 9×10 -5 to 5×10 -4 Torr in the presence of sulfur vapors; forming a second insulating layer on the electroluminescent layer; and forming back side electrodes on the second insulating layer.
Claim 18
Dependent Claim
35 words
A process according to claim 13, wherein the electroluminescent layer is formed by simultaneous vapor deposition of a mixture containing the strontium sulfide as the matrix by electron beam evaporation and sulfur by resistance heating.
Claim 19
Dependent Claim
37 words
A process according to claim 13, further comprising: forming a first ZnS layer between the first insulating layer and the electroluminescent layer; and forming a second ZnS layer between the electroluminescent layer and the second insulating layer.
Claim 20
Dependent Claim
60 words
A process according to claim 13, wherein the first insulating layer includes a first SiO 2 film and a first Ta 2 O 5 film formed on the first SiO 2 film, and the second insulating layer includes a second Ta 2 O 5 film and a second SiO 2 film formed on the second Ta 2 O 5 film.
Claim 21
Dependent Claim
45 words
A process according to claim 13, wherein the substrate is a glass substrate, the transparent electrodes are formed in a stripe-shaped pattern, and the back side electrodes are metallic electrodes formed in a stripe-shaped pattern so as to cross the transparent electrodes at right angles.
Claim 22
Dependent Claim
60 words
A process according to claim 13, wherein the electroluminescent layer has a lattice constant of not more than 6.07Å, a half-width value at the (111) face of not more than 0.21 degree, and the content of sulfur in the strontium sulfide of the electroluminescent layer is at least 0.66 in terms of a fluorescent x-ray diffraction intensity ratio of I(S)/I(Sr)+I(S).
Claim 23
Dependent Claim
32 words
A process according to claim 13, wherein the electroluminescent layer comprises strontium sulfide as a matrix and contains at least one of halides and sulfides of cerium, europium, thulium, terbium and samarium.
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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) | 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 |