Image Number 4 for United States Patent #6307645.
In a hi-fi color printing system, an inverted halftone screen is provided having the same angle and frequency as a halftone screen for an opposing color. The dots of the inverse halftone screen are configured to be located midway between the centers of the dots of the half-tone screen. The halftone screen and inverted halftone screen are used in the printing process to extend the gamut of colors within a printing system, render improved neutral colors, and provide an improved transition through neutral regions of color space. The present invention allows for additional printing of multiple colors without the need for increasing the number of screens used in the image processing system.