Color 3D printing just got a huge boost from the Fraunhofer Institute for Computer Graphics Research in Germany. Until now, Mcor’s paper 3D printing and 3D Systems binder-jetting processes have been among the best at creating vivid, colorful prints, but, according to MIT Technology Review, Alan Brunton, et al. have developed a new software and 3D printing process, relying on translucent materials, that brings an almost lifelike quality to full-color prints.
As opposed to Mcor or 3D Systems technologies, the Franhofer researchers bet on multi-jet printers, like Stratasys Connex technique. For that reason, they developed software that optimizes multi-jet 3D printing to produce more accurate colors, specifically an Objet500 Connex3. Due to the translucency of materials for multi-jet printing, which is necessary at this point for UV light to pass through and cure them, the details of prints made by such a process may be blurred. However, through their software, the researchers were able to design an approach that would yield an incredible amount of detail.
Firstly, the team’s software utilizes voxels, in order to capture created color detail and Brunton, et al. tackle the translucency problem by using a “layered halftone” approach. As a variety of different colored pixels add up to create a full-color photo, the researchers created 3D objects with multiple layers of different colored voxels. This creates a different shading effect from the outer layers to the inner layers.
As you can imagine, writing a program that can accurately predict how light will diffuse through a 3D object is no easy task. But, if you’re up for sifting through the formulas that make up such software, you can read the whole paper here. Otherwise, you can sit back and wait for the team’s research to gradually make its way into the industry. Brunton, et al. believe that their technique will work just as well, if not better, as new resins and processes are developed that need not be as translucent. Other issues experienced were the lack of a black material and the fact that the color of the support material often blended with the printed object. I can only imagine what they’d be able to produce when the next generation of Connex machines comes out.