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US4580877A Expired / Lapsed US ⏱️ 0.0 years remaining

Combined display panel of liquid crystal display and electroluminescent display

Assignee: Sharp Corp
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Filing: 1982-07-06
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Granted: 1986-04-08
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Expires: 2002-07-06
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Abstract

Abstract A combined display panel comprises a liquid crystal display (LCD) and an electroluminescent display (EL). In addition to the conventional emitting agents, an electroluminescent layer of the EL contains a pigment element for reflecting radiation toward the LCD. Preferably, the LCD is a guest-host type and the EL is a powder type. The material of the pigment element may be selected from a white pigment including barium titanate and titanium oxide. A semi-transparent film such as a parchment paper may be inserted between the LCD and the EL.

Inventors

  • 👤 Junichi Washo

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 14:16
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133602; G02F1/133603

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 44 words
A combined display panel comprising: a liquid crystal display containing a liquid crystal layer; and an electroluminescent display including an electroluminescent layer; the electroluminescent layer containing a pigment element for reflecting radiation toward the liquid crystal layer, in addition to agents for emitting electroluminescence.
Claim 2
Dependent Claim 44 words
A combined display panel comprising: a liquid crystal display containing a liquid crystal layer; and an electroluminescent display including an electroluminescent layer; the electroluminescent layer containing a pigment element for reflecting radiation toward the liquid crystal layer, in addition to agents for emitting electroluminescence.
Claim 3
Dependent Claim 14 words
The display of claim 1, wherein the liquid crystal display is the guest-host type.
Claim 4
Dependent Claim 13 words
The display of claim 1, wherein the electroluminescent display is the powder type.
Claim 5
Dependent Claim 12 words
The display of claim 1, wherein the pigment element provides white color.
Claim 6
Dependent Claim 24 words
The display of claim 1, wherein the material of the pigment element is selected from the group consisting of barium titanate or titanium oxide.
Claim 7
Dependent Claim 44 words
The display of claim 1, wherein the surface of the substrate of the electroluminescent display in front of the electroluminescent display is made rugged so that the radiation passing through the liquid crystal display and the electroluminescence from the electroluminescence layer is highly scattered.
Claim 8
Dependent Claim 37 words
The display of claim 1, further comprising a semi-transparent film disposed between the electroluminescent display and the liquid crystal display for scattering the radiation passing through the liquid crystal display and the electroluminescence from the electroluminescence layer.
Claim 9
Dependent Claim 13 words
The display of claim 7, wherein the semi-transparent film is a parchment paper.
Claim 10
Dependent Claim 79 words
A combined display panel comprising: a liquid crystal display containing a liquid crystal layer; and an electroluminescent display including an electroluminescent layer disposed behind the liquid crystal display to provide illumination therefor; said electroluminescent layer containing a pigment element for reflecting radiation toward the liquid crystal layer in the presence of incident light upon the liquid crystal device or upon activation of the electroluminescent display to provide electroluminescence in the absence of incident light upon the liquid crystal display.
Claim 11
Dependent Claim 79 words
A combined display panel comprising: a liquid crystal display containing a liquid crystal layer; and an electroluminescent display including an electroluminescent layer disposed behind the liquid crystal display to provide illumination therefor; said electroluminescent layer containing a pigment element for reflecting radiation toward the liquid crystal layer in the presence of incident light upon the liquid crystal device or upon activation of the electroluminescent display to provide electroluminescence in the absence of incident light upon the liquid crystal display.

References Cited (Backward Citations)

US3881809A Cited
US3840695A Cited
US4208869A Cited
US4212048A Cited
US4196973A Cited
GB2054119A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-04-07 1989-10-07 1990-04-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-04-07 1993-10-07 1994-04-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-04-07 1997-10-07 1998-04-08 $7700.00 Window Closed / Lapsed

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