Hexagonal dot packing offers advantages for electrophotographic (EP) printing over conventional dot placement on a square grid. These advantages derive from a reduced neighborhood with which each dot interacts. Hexagonal dot packing has exhibited better grayscale performance with small clusters. Multiple dot centers in each tile allow obtaining more gray levels for a particular screen frequency. As a limiting case of multiple dot centers in a tile, stochastic screening on hexagonal and square grids is examined using a commercially available printing system. A novel method for comparing halftone spatial frequency components for all gray levels is demonstrated.
Tomasz J. Cholewo, Steve Weed, Brian Cooper, Michael Lhamon, "Enhanced EP halftones with hexagonal dot packing" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP16), 2000, pp 708 - 713, https://doi.org/10.2352/ISSN.2169-4451.2000.16.1.art00072_2