In fact, it was the quest to determine the best dot shapes, angles, and rulings for screening solids that ultimately led to the development of plate cell patterns. Results of our research to determine the optimum screen for transferring ink indicate that cell counts for screening solids are actually in the same range as cell counts of anilox rollers. But funny things happen to normal halftone screens when scaled up to these high frequencies. First, the non-dot area can have peculiar shapes. For example, the non-dot area of a round dot is actually an inverted diamond.
Users select the cell pattern of choice along with other attributes of the job.
In-Rip software tells the cell patterns to be imaged in solid areas and normal halftone screens to be imaged in contone areas. Cells transfer through the reproduction process from digital file to film to plate. Because cell patterns are made of relatively few pixels at these high frequencies, best results are obtained if the imagesetter is calibrated for flexo. This result is a smoother cell with higher density and harder edges. This cell enlargement compensates for the fact that the cell will shrink on the final plate.