Color correction system for an electrophotographic copying machine

• US 4,967,265 A
• Filed: 04/04/1989
• Issued: 10/30/1990
• Est. Priority Date: 04/04/1989
• Status: Expired due to Fees

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Ossman, Kenneth R., Lehman, Richard F., Rees, James D.
• Primary Examiner(s): Coles, Sr., Edward L.
• Assistant Examiner(s): Grant, II, Jerome
• Application Number:
  US07/332,821
• Time in Patent Office: 574 Days
• Field of Search: 358/80, 358/75
• US Class Current: 358/518
• CPC Class Codes: G03G 15/01 for producing multicoloured copies colour correction in photography G03C; colour correction in printing plate production
• CPC Class Codes: H04N 1/508 using the same reproducing head for two or more colour components
• CPC Class Codes: H04N 1/60 Colour correction or control H04N1/54 takes precedence

Abstract

A color correction system for a color copier is enabled by means of a low resolution RIS unit attached to a light/lens scan system which creates an electronic raster image simultaneously with formation of a color latent image. The RIS output signals are used to modulate the output of a ROS unit which exposes the color latent image to a modulated color correction pattern. Color developer units are enabled to successively develop each color.

Claims

1. An electrophotographic copying apparatus utilizing a raster input scanner (RIS) for color correction, the apparatus including a platen in a horizontal plane for supporting a colored original to be reproduced;

scan/illumination means mounted for movement beneath said platen;

imaging means coupled to said scan/illumination means and adapted for movement therewith for forming successive latent images corresponding to different color separations of said document on the charged surface of a photoconductive member at a first exposure station, said RIS coupled to said scan illumination means, and adapted for movement therewith so as to scan said document simultaneously with said imaging means, said apparatus further including control means adapted to transmit a modulated color correction light pattern in registration onto each color laten image formed by said imaging means at a second exposure station, said control means including means for processing output signals from said RIS and for applying control signals to a raster output scanner which generates the modulated color corrected output signal.