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US5003221A Expired / Lapsed US ⏱️ 0.0 years remaining

Electroluminescence element

Assignee: Hoya Corp
•
Filing: 1988-08-26
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Granted: 1991-03-26
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Expires: 2008-08-26
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Abstract

Abstract In an EL element of this invention, a thin film layer is formed between a transparent substrate and a layer formed adjacent to the transparent substrate, and the refractive index of the thin film layer is changed to be approximated to those of these layers toward the interfaces between the thin film layer and the corresponding layers, so that a difference in refractive index at these interfaces is minimized. The thin film layer may be formed between at least two adjacent layers formed on the transparent substrate.

Inventors

  • 👤 Yasumoto Shimizu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 10:06
CPC Classifications
H; H05; H05B; H05B33/00; H05B33/12; H05B33/22

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 130 words
An electroluminescence element in which a plurality of layers including at least a transparent electrode layer, a back electrode layer, and at least one layer including an electroluminescent layer disposed between said back electrode layer and said transparent electrode layer, wherein said transparent electrode layer is formed on a transparent substrate, so as to emit light upon the application of an electric field between said transparent electrode layer and said back electrode layer; wherein a thin film layer for preventing electroluminescent light from being reflected on paths from said luminescent layer to said transparent substrate is disposed at an intervening portion between said transparent substrate and said electroluminscent layer and a refractive index of said thin film layer changes in a direction from the transparent substrate toward the electroluminesecent layer.
Claim 2
Dependent Claim 130 words
An electroluminescence element in which a plurality of layers including at least a transparent electrode layer, a back electrode layer, and at least one layer including an electroluminescent layer disposed between said back electrode layer and said transparent electrode layer, wherein said transparent electrode layer is formed on a transparent substrate, so as to emit light upon the application of an electric field between said transparent electrode layer and said back electrode layer; wherein a thin film layer for preventing electroluminescent light from being reflected on paths from said luminescent layer to said transparent substrate is disposed at an intervening portion between said transparent substrate and said electroluminscent layer and a refractive index of said thin film layer changes in a direction from the transparent substrate toward the electroluminesecent layer.
Claim 3
Dependent Claim 28 words
An electroluminescence element according to claim 1, wherein said thin film layer is formed between said transparent substrate and said transparent electrode layer formed on said transparent substrate.
Claim 4
Dependent Claim 34 words
An electroluminescence element according to claim 1, wherein said thin film layer is formed between said transparent electrode layer formed on said transparent substrate and a dielectric layer formed on said transparent electrode layer.
Claim 5
Dependent Claim 117 words
An electroluminescence element according to claim 1, wherein said thin film layer is formed such that a value x or y of materials expressed by a formula MO x or LN y is changed in a direction of thickness, so that the refractive index of said thin film layer is changed to be approximated to a refractive index of a corresponding one of other layers contacting said thin film layer toward an interface between said thin film layer and the corresponding one of said other layers: where M, L . . . metal element selected from the group of Si, Al, Mg, Ta, Ti, Zr, Hf, Y O . . . oxygen N . . . nitrogen
Claim 6
Dependent Claim 91 words
An electroluminescence element according to claim 1, wherein said thin film layer is formed of a material containing silicon (Si) and oxygen (0) expressed by a formula SiO x , and a value x of the material is changed in a direction of thickness, so that the refractive index of said thin film layer is changed to be approximated to a refractive index of a corresponding one of other layers contacting said thin film layer toward an interface between said thin film layer and the corresponding one of said other layers
Claim 7
Dependent Claim 85 words
An electroluminescence element according to claim 1, wherein said thin film layer is formed by mixing two kinds of materials having different refractive indices, and a mixing ratio of the materials is changed in a direction of thickness, so that the refractive index of said thin film layer is changed to be approximated to a refractive index of a corresponding one of other layers contacting said thin film layer toward an interface between said thin film layer and the corresponding one of said other layers.
Claim 8
Dependent Claim 22 words
An electroluminescence element according to claim 6, wherein the two kinds of materials comprise SiO 2 and Ta 2 O 5 .
Claim 9
Dependent Claim 92 words
A method of manufacturing an electroluminescence element of claim 1, wherein said thin film layer is a composite film of two kinds of materials consisting of first and second materials, and said thin film layer is formed by simultaneously sputtering the two kinds of materials consisting of the first and second materials and continuously or stepwisely changing a mixing ratio of the first and second materials, so that the mixing ratio of the first and second materials in said thin film layer is continuously or stepwisely changed along a direction of thickness.
Claim 10
Dependent Claim 21 words
A method according to claim 8, wherein the two kinds of materials comprise SiO 2 and Ta 2 O 5 .

References Cited (Backward Citations)

US3854070A Cited
US4590128A Cited
US4670355A Cited
JPS61225795A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-03-25 1994-09-24 1995-03-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-03-25 1998-09-24 1999-03-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-03-25 2002-09-24 2003-03-26 $7700.00 Window Closed / Lapsed

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