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US4734723A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrophotograhic printer

Assignee: NEC Home Electronics Ltd
•
Filing: 1986-06-16
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Granted: 1988-03-29
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Expires: 2006-06-16
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Abstract

Abstract An electrophotographic printer which is equipped with a photoreceptor, a charge device, an optical head, a developing device and a transfer device. The optical head has an array of electroluminescent devices arranged along one edge of a substrate and an array of light waveguide strips for transmitting the light from each of the electroluminescent devices to the other edge of the substrate which is to be brought into a face-to-face relationship with the photoreceptor.

Inventors

  • 👤 Yoshimitsu Ishitobi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 04:33
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/435; B41J2/447; B41J2/45; B41J2/451

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 159 words
An electrophotographic printer comprising: a photoreceptor; a charging device positioned adjacent said photoreceptor for charging the same; a developing device positioned adjacent said photoreceptor for forming a toner density pattern on a charged area thereof; a transfer device positioned adjacent said photoreceptor for transferring a toner image therefrom onto a sheet of paper; an optical head, positioned adjacent said photoreceptor and including a substrate; a light-emitting means for emitting light arranged along one edge portion of the substrate, said light-emitting means comprising an array of electro-luminescent devices, said electro-luminescent devices comprising a first metal electrode layer formed on said substrate, an electro-luminescent material layer formed on said first electrode layer, an electrical insulating layer formed on said electro-luminescent material layer, and a second metal electrode layer formed on said electrical insulating layer; and a light transmitting means for transmitting light emitted from said emitting means to said photoreceptor; said transmitting means comprising an array of light wave guide strips.
Claim 2
Dependent Claim 159 words
An electrophotographic printer comprising: a photoreceptor; a charging device positioned adjacent said photoreceptor for charging the same; a developing device positioned adjacent said photoreceptor for forming a toner density pattern on a charged area thereof; a transfer device positioned adjacent said photoreceptor for transferring a toner image therefrom onto a sheet of paper; an optical head, positioned adjacent said photoreceptor and including a substrate; a light-emitting means for emitting light arranged along one edge portion of the substrate, said light-emitting means comprising an array of electro-luminescent devices, said electro-luminescent devices comprising a first metal electrode layer formed on said substrate, an electro-luminescent material layer formed on said first electrode layer, an electrical insulating layer formed on said electro-luminescent material layer, and a second metal electrode layer formed on said electrical insulating layer; and a light transmitting means for transmitting light emitted from said emitting means to said photoreceptor; said transmitting means comprising an array of light wave guide strips.
Claim 3
Dependent Claim 43 words
An electrophotographic printer as claimed in claim 1 further comprising: an optical head drive, said optical head drive supplying an electrical signal of varying amplitude to each of said first electrode layers to cause said electrolumimescent devices to produce different quantities of light.
Claim 4
Dependent Claim 33 words
An electrophotographic printer as claimed in claim 2, wherein said electroluminescent material layer extends in the form of an uninterrupted strip to the other edge portion of said substrate, forming said light waveguide.
Claim 5
Dependent Claim 27 words
An electrophotographic printer as claimed in claim 3, wherein said second electrode layer are interconnected on said one edge of said substrate to form a common electrode.
Claim 6
Dependent Claim 33 words
An electrophotographic printer as claimed in claim 4, wherein said electrical insulating layer between adjacent strips formed by said electrluminescent devices and said light waveguide strips is overlaid with a metal light-shielding layer.
Claim 7
Dependent Claim 20 words
An electrophotographic printer as claimed in claim 5, wherein said first and second metal electrode layers are composed of Al.
Claim 8
Dependent Claim 17 words
An electrophotographic printer as claimed in claim 6, wherein said electroluminescent material layer is composed of ZnS:Mm.
Claim 9
Dependent Claim 17 words
An electrophotographic printer as claimed in claim 5, wherein said electroluminescent material layer is composed of ZnS:Mn.

References Cited (Backward Citations)

US3806759A Cited
US4006383A Cited
US4435064A Cited
US4549784A Cited
US4535341A Cited
US4617195A Cited
US4557581A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-03-29 1991-09-28 1992-03-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-03-29 1995-09-28 1996-03-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-03-29 1999-09-28 2000-03-29 $7700.00 Window Closed / Lapsed

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