Researchers at the Universities of Bristol and Bath in the UK have developed a technique to create a sprayable display on a 3D printed object. Working with researchers at MIT in the US, the team aims to combine plastic 3D printing and sprayable touchscreen technique in a single machine.
The ProtoSpray sprayable display technique uses conductive channels built into a 3D printed design to create the base electrodes for the display. These electrodes are then sprayed with dielectric and active materials to produce illumination and even touchscreens. The team looked at six different topologies, analysing the spray orientations, surface topologies and printer resolutions, to see how spray nozzles can be integrated into traditional 3D printers.
A video of the technique is here
The technique is based around electroluminescent (EL) ink which requires uniform deposition to avoid unpredictable electrical behaviour and short circuits and needs to be in thinner layers, for energy efficiency, than commodity 3D printer resolution allow. Conductive electrodes for the display traditionally also have to be made from optically transparent materials to allow light through from the EL layer, but 3D printers can't currently process these materials and running the material through a filament or high temperature extrusion risk the loss of the electrical properties.
Instead, a coating of EL ink and a dielectric layer is sprayed on interconnected electrodes created by 3D printing conductive filaments to supply electrical power to displays.
"3D printers have enabled personal fabrication of objects but our work takes this even further to where we print not only plastic but also other materials that are essential for creating displays,” said researcher Ollie Hanton at the University of Bristol. “Using 3D printing of plastics and spraying of materials that light up when electricity is applied, we can support makers to produce objects of all shapes that can display information and detect touch. Our vision is to make screen/display a fundamental expressive medium in the same way people currently use