Patent · US Expired

Color image printing apparatus

US4884080A · kind A · utility

50Cited by
12References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 2, 1987
Grant dateNov 28, 1989
Priority date
Expiry dateJun 2, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/4058
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A color image printing apparatus prints one pixel by superposing a predetermined dots of three colors within a 3.times.3 dot matrix in accordance with a density of the pixel. The positions of the printed dots within the dot matrix are stored as a dot pattern for each color. One dot pattern is used for each of a plurality of densities included in one density range. The printing energy for each of the dots included in the dot pattern is controlled in accordance with the density level of the pixel. The dot pattern is different for each color and three dot patterns are stored for each color and for each density range. These three dot patterns are repeatedly used for every three pixels which are continuous in the horizontal direction. These three dot patterns have two or three texture directions. The texture direction other than the vertical direction is different for each color.

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