Patent ID: 6163382
Filing Date: 2000-12-19
Classification: G03F,H04N

Abstract:
A method for producing a color image that is not continuous-tone but faithfully represents a continuous-tone color original comprising the steps of:(a) producing a first image that is not continuous tone and corresponds to a first color component of the continuous-tone color original, by forming in said first image an electronically generated pixel pattern creating substantially continuous, substantially parallel lines at a frequency of between about 100 and 400 lines per inch, such that the width of each one of said lines at a given point in the first image varies in relation to the optical density of said first color component at a corresponding point in the continous-tone original, said substantially parallel lines in said first image having a first line frequency, and said substantially parallel lines in said first image defining a first direction;(b) producing a second image that is not continuous tone and corresponds to a second color component of the continuous-tone color original, by forming in said second image an electronically generated pixel pattern creating substantially continuous, substantially parallel lines at a frequency of between about 100 and 400 lines per inch, such that the width of each one of said lines at a given point in the second image varies in relation to the optical density of said second color component at a corresponding point in the continuous-tone original, said substantially parallel lines in said second image having a second line frequency substantially equal to said first line frequency, and said substantially parallel lines in said second image defining a second direction rotated from said first direction;(c) producing a third image that is not continuous tone and corresponds to a third color component of the continuous-tone color original, by forming in said third image an electronically generated pixel pattern creating substantially continuous, substantially parallel lines at a frequency of between about 100 and 400 lines per inch, such that the width of each one of said lines at a given point in the third image varies in relation to the optical density of said third color component at a corresponding point in the continuous-tone original, said substantially parallel lines in said third image having a third line frequency substantially equal to said first line frequency, and said substantially parallel lines in said third image defining a third direction rotated from both said first direction and said second direction;wherein said producing of each of said first, second and third images comprises scanning an image carrier with one or more directly exposing scanning beams; and(d) combining said first, said second and said third images in registration to thereby produce said color image that is not continous tone but faithfully represents the continuous tone color original.