US4233381A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for increasing the apparent resolution of developed electrophotographically reproduced images
Assignee: HP Indigo BV
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Filing: 1978-11-09
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Granted: 1980-11-11
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Expires: 1998-11-09
Abstract
Abstract My invention comprises charging a photoconductive surface in the dark and exposing it to a light and shade image of the original to produce a latent electrostatic image. The latent electrostatic image is then developed by any method known to the art employing a liquid developing fluid, and the apparent resolution or sharpness of the developed image is increased by exposing the developed image, while on the photoconductor, to the action of blanket light. The sharpened image may then be transferred to a carrier sheet by any method known to the art. The apparatus of my invention comprises a conventional electrophotographic reproduction apparatus in which a means is provided for subjecting a liquid-developed image, while on the photoconductor, to the action of blanket light. This means is positioned to act before the liquid-developed image is transferred to a carrier sheet after it has been developed, if a transfer is to take place.
Inventors
- 👤 Benzion Landa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:55
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/10; G03G15/14; G03G15/16; G03G15/169
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
In a method of electrophotography in which a photoconductor is charged in a charging step, subjected to a light and shape image of a document to be copied to produce a latent electrostatic image of the document on the surface of the photoconductor in an exposing step, the latent electrostatic image is developed by a liquid-carried toner to provide a visible image on the photoconductor in a development step, and the visible image is transferred to a carrier sheet after it has been developed in a transferring step, the improvement comprising flooding the front of the visible electrostatic image with blanket light to increase the apparent resolution of the developed image before it is transferred to a carrier sheet and then practicing the transferring step.
Claim 2
Dependent Claim
125 words
In a method of electrophotography in which a photoconductor is charged in a charging step, subjected to a light and shape image of a document to be copied to produce a latent electrostatic image of the document on the surface of the photoconductor in an exposing step, the latent electrostatic image is developed by a liquid-carried toner to provide a visible image on the photoconductor in a development step, and the visible image is transferred to a carrier sheet after it has been developed in a transferring step, the improvement comprising flooding the front of the visible electrostatic image with blanket light to increase the apparent resolution of the developed image before it is transferred to a carrier sheet and then practicing the transferring step.
Claim 3
Dependent Claim
83 words
An improved method of electrophotography including the steps of forming a latent electrostatic image of an original to be copied on the surface of an electrostatically charged photoconductor and toning the said latent electrostatic image with a liquid-carried toner to develop the same, the improvement comprising increasing the apparent resolution of the developed electrostatic image by subjecting the front of the same to the action of a blanket of light and then transferring the developed image having increased resolution to a carrier sheet.
Claim 4
Dependent Claim
83 words
An improved method of electrophotography including the steps of forming a latent electrostatic image of an original to be copied on the surface of an electrostatically charged photoconductor and toning the said latent electrostatic image with a liquid-carried toner to develop the same, the improvement comprising increasing the apparent resolution of the developed electrostatic image by subjecting the front of the same to the action of a blanket of light and then transferring the developed image having increased resolution to a carrier sheet.
Claim 5
Dependent Claim
115 words
In an apparatus for making copies of a document by electrophotography having a photoconductor; means for charging the photoconductor; exposing means for subjecting the charged photoconductor to a light and shade image of the document being copied to form a latent electrostatic image; means for developing the latent electrostatic image with a liquid developer; means for transferring the developed image to a carrier sheet; and means for moving the photoconductor past the charging means, the exposing means, the developing means, and the transferring means in succession; the improvement comprising interposing a light source for flooding the front of the developed electrostatic image on the photoconductor with light between the developing means and the transferring means.
Claim 6
Dependent Claim
115 words
In an apparatus for making copies of a document by electrophotography having a photoconductor; means for charging the photoconductor; exposing means for subjecting the charged photoconductor to a light and shade image of the document being copied to form a latent electrostatic image; means for developing the latent electrostatic image with a liquid developer; means for transferring the developed image to a carrier sheet; and means for moving the photoconductor past the charging means, the exposing means, the developing means, and the transferring means in succession; the improvement comprising interposing a light source for flooding the front of the developed electrostatic image on the photoconductor with light between the developing means and the transferring means.
References Cited (Backward Citations)
US3707138A
Cited
DE2219005A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-11 | 1984-05-12 | 1984-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-11 | 1988-05-12 | 1988-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-11 | 1992-05-12 | 1992-11-11 | $7700.00 | Window Closed / Lapsed |