Digital halftoning techniques using threshold matrices have clear advantages in their speed of operation together with the possibility of controlling the produced dot patterns. However, due to an inherent restriction discussed in this article, the quality of dispersed dots halftones produced with this technique is not always satisfactory. In this article we describe a technique that overcomes this restriction, thereby allowing for an individual design of each tint value without any loss of speed. We also propose a design strategy for obtaining near optimal tints without losing the necessary correlation between tints. High quality reproduction of both tints and transitions between different intensity levels is thus possible. This technique also allows for new types of dispersed dot halftones with predefined micro structures. Halftones with micro structures are less sensitive to both mechanical and optical dot gain and can advantageously be used in processes with severe dot gain or low printing precision. In this article we present two types of micro structures together with several image examples.
Fredrik Nilsson, "Digital Halftoning using Pre-Computed Maps" in Journal of Imaging Science and Technology, 1999, pp 153 - 159, https://doi.org/10.2352/J.ImagingSci.Technol.1999.43.2.art00010