Accurate color reproduction is important in many applications of 3D printing, from design prototypes to 3D color copies or portraits. Although full color is available via other technologies, multi-jet printers have greater potential for graphical 3D printing, in terms of reproducing complex appearance properties. However, to date these printers cannot produce full color, and doing so poses substantial technical challenges, from the shear amount of data to the translucency of the available color materials. In this article, we propose an error diffusion halftoning approach to achieve full color with multi-jet printers, which operates on multiple isosurfaces or layers within the object. We propose a novel traversal algorithm for voxel surfaces, which allows the transfer of existing error diffusion algorithms from 2D printing. The resulting prints faithfully reproduce colors, color gradients and fine-scale details.
Tone reproduction in FDM prints. Some recent work has focused on the challenging task of improving tone reproduction in fused deposition modeling (FDM) printing. Hergel and Lefebvre @cite_36 optimize seam placement in multi-filament FDM prints to hide or reduce artifacts from changing filaments. @cite_14 perform a type of halftoning for FDM printers while maintain long filament paths. Switching filament heads not only creates artifacts, but also increases print time. Both of these methods are specific to FDM printers.
@cite_36 @cite_14
2169539576 2165285514
Fused Filament Fabrication is an additive manufacturing process by which a 3D object is created from plastic filament. The filament is pushed through a hot nozzle where it melts. The nozzle deposits plastic layer after layer to create the final object. This process has been popularized by the RepRap community. In this work we detail a method that leverages the two color heads of recent low-end fused deposition modeling FDM 3D printers to produce continuous tone imagery. The challenge behind producing such two-tone imagery is how to finely interleave the two colors while minimizing the switching between print heads, making each color printed span as long and continuous as possible to avoid artifacts associated with printing short segments. The key insight behind our work is that by applying small geometric offsets, tone can be varied without the need to switch color print heads within a single layer. We can now effectively print two-tone texture mapped models capturing both geometric and color information in our output 3D prints.