Computer Science and Artificial Intelligence Laboratory (CSAIL)
Massachusetts Institute of Technology
2017 SIGGRAPH/ACM Transactions on Graphics 36(4), July 2017
Abstract
Appearance reproduction is an important aspect of 3D printing.
Current color reproduction systems use halftoning methods that
create colors through a spatial combination
of different inks at the object's surface. This introduces a
variety of artifacts to the object, especially when viewed from a closer
distance.
In this work, we propose an alternative color reproduction method
for 3D printing. Inspired by the inherent ability of 3D printers to layer
different materials on top of each other, 3D color contoning
creates colors by combining inks with various thicknesses inside the
object's volume.
Since inks are inside the volume, our technique
results in a uniform color surface with virtually invisible
spatial patterns on the surface. For color prediction, we introduce
a simple and highly accurate spectral model that relies on a
weighted regression of spectral absorptions.
We fully characterize the proposed framework by addressing
a number of problems, such as material arrangement,
calculation of ink concentration, and 3D dot gain.
We use a custom 3D printer to fabricate and
validate our results.