The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 03, 1992
Filed:
Aug. 02, 1990
Chris A Storlie, Boise, ID (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method and system for controlling the alignment and registration of color images such as those of cyan, yellow, magenta, and black (C, Y, M, K) which are successively printed on a photoconductive drum and then transferred from the drum to paper during electrophotographic color printing. Each scccessive color image printed on paper is fused therein, and then vertical, horizontal and angular error signals are generated after each fusion. These error signals represent the difference between an original image reference position and the image position after each color image fusion into the paper. These error signals are then processed in a closed loop feedback control system in such a manner as to control the position and scan rate of a laser beam being projected onto the photoconductive drum to thereby cause the next-printed color image to be aligned with the previously printed color image. In this manner, the electro-optical control of each successively printed latent image formed on the photoconductive drum is responsible for the above alignment and paper correction without requiring complex mechanical schemes to accomplish same.