The average American spends a lot of time staring at phone and computer screens — generally an estimated seven to 11 hours daily. Organic light-emitting diode (OLED) screens have gained popularity over LED versions in recent years because of benefits including brighter images, flexible construction, and less energy consumption resulting from the different way their pixels light up.
But OLED manufacturing is more expensive and usually happens at large, energy-intensive factories. Thus, when OLED screens break, they can be expensive and time-consuming for consumers to replace. University of Minnesota researchers had a breakthrough using a customized 3D printer to manufacture a flexible OLED display. The advancement could allow consumers to 3D print their own OLED screens at home or work.
“The nice part about our research is that the manufacturing is all built in, so we’re not talking 20 years out with some ‘pie in the sky’ vision,” Michael McAlpine, a University of Minnesota engineering professor, said in a news release. “This is something that we actually manufactured in the lab, and it is not hard to imagine that you could translate this to printing all kinds of displays ourselves at home or on the go within just a few years, on a small portable printer.”
Challenges
This is not the first global attempt at using additive manufacturing to create OLEDs, but the Minnesota researchers say it is the first successful, functioning, and fully 3D-printed OLED. Others have been able to partially print displays and incorporated some non-3D printing techniques, such as spin-coating or thermal evaporation. Previously, the Minnesota team had struggled with achieving uniformity in the light-emitting layers they created.
The technology
The team used two different kinds of printing to create the display’s six layers. They extrusion printed the electrodes, interconnects, insulation, and encapsulation. They used the same 3D printer at room temperature to spray paint the active layers.
The 1.5-inch square prototype contains 64 pixels. All of the pixels worked and displayed light, which is considered a big victory.
“I thought I would get something, but maybe not a fully working display,” said Ruitao Su, a former University of Minnesota mechanical engineering Ph.D. graduate who is now a postdoctoral researcher at the Massachusetts Institute of Technology.
What’s next
The team used a very expensive, customized 3D printer that they say costs as much as a Tesla Model S. (The base price for those vehicles is about $90,000.) It will take some work to adapt the technology before consumers can afford to manufacture their own OLEDs at home.
The researchers will continue perfecting their prototype design. They aim to create even higher resolution, brighter OLEDs.
Because the 3D-printed OLED display is flexible, it could be used for a lot of purposes, including soft electronics or wearable devices.
