Browse Prior Art Database

COMBINATION SCREENER AND DIGITAL ASSIST ROS

IP.com Disclosure Number: IPCOM000025928D
Original Publication Date: 1989-Feb-28
Included in the Prior Art Database: 2004-Apr-04
Document File: 2 page(s) / 50K

Publishing Venue

Xerox Disclosure Journal

Abstract

A requirement for color printers is that the output copy be color and tone corrected. A system for combining digital assist color correction and sequential tone screening in a single device is realized by combining an addressable LED ROS array with a transparent line screen having a spatially modulated density. The modulated output from the array is imaged onto a photoreceptor via a linear gradient index lens array. The resulting screened modulated image contains exposure levels corresponding to black, white, and color areas.

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XEROX DISCLOSURE JOURNAL

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COMBINATION SCREENER AND Proposed Classification DIGITAL ASSIST ROS U.S. c1.355/4 Richard F. Lehman Int. C1. G03g 15/01

A requirement for color printers is that the output copy be color and tone corrected. A system for combining digital assist color correction and sequential tone screening in a single device is realized by combining an addressable LED ROS array with a transparent line screen having a spatially modulated density. The modulated output from the array is imaged onto a photoreceptor via a linear gradient index lens array. The resulting screened modulated image contains exposure levels corresponding to black, white, and color areas.

A further refinement of the combined area ROS/screen unit is to form LED pixels in the ROS in a diamond or circular configuration rather than the conventional square pattern, by fabricating the array with each individual pixel rotated 45". This pixel arrangement eliminates the requirement for a physical screen and produces the desired toning by combining LED spacing and placement with line modulation.

Volume 14 Number 1 January/February 1989 19

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    XEROX DISCLOSURE JOURNAL Volume 14 Number 1 January/February 1989

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