Patent · US Expired

Method and apparatus for creating color copies of an original by an electrostatic charging process

US4007489A · kind A · utility

29Cited by
7References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1975
Grant dateFeb 8, 1977
Priority date
Expiry dateSep 19, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0142
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An original is sampled line-by-line at a predetermined number of points along each line and sampling signals indicative of the density of the original in each of three colors are furnished while electrographic paper or film is transported past a first, second and third recording station. At each recording station a line of electrodes having a length exceeding the width of the copy to be made and exceeding in number the number of sampling points of the original along each line extends in a direction perpendicular to the direction of transport of the paper. A mark on the paper is sensed at each station and the deviation of the position of the mark from a desired position in the line direction determines which electrode will be used to start the recording of the line. In the direction of transport, the deviation of the position of said mark from a desired position is sensed and the start of the line recording varied in time in accordance therewith.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.