Scientists at the Fraunhofer Institute for Applied Polymer Research IAP in Potsdam-Golm have developed a pilot production facility able to print OLEDs as well as organic solar cells on an industrial scale. The scientists worked together with mechanical engineering company Mbraun to develop the facility.
OLEDs and solar cells can be printed at the facility from solutions containing luminescent organic molecules and absorptive molecules respectively, which makes printing them onto a carrier film very straightforward. Usually, printing OLEDs and solar cells involve vaporising small molecules in a high vacuum, making it a very expensive process.
Scientists had previously only ever used various printing technologies to design components on a laboratory scale. They can now produce larger sample series, which is particularly advantageous for producing tailored solutions in relatively small numbers.
'We’re now able to produce organic components under close-to-real-life manufacturing conditions with relative ease. Now for the first time it will be possible to translate new ideas into commercial products,’ commented Dr Armin Wedel, head of division at the Fraunhofer IAP.
At the heart of the pilot plant is a robot that controls different printers. OLEDs are applied to the carrier material one layer at a time using a variety of starting materials. This produces a very homogenous surface that creates a perfect lighting layer.
‘We’re able to service upscale niche markets by offering tailored solutions, as we can apply the organic electronic system to customers’ specifications, just like in digital printing,’ said Wedel.
Industry experts estimate that printed OLEDs has promise of becoming a billion-dollar market. ‘The focus in Germany and Europe is on OLED lighting because this is the home market for large companies such as Osram and Philips,’ explained Wedel.
Dr Martin Reinelt, CEO of Mbraun in Garching, added: ‘The manufacturing facility will help secure competitive advantages in this particular segment of the market. It strengthens the German research community, and also demonstrates the capabilities of German plant engineering.’
OLEDs have several advantages over conventional display technologies. Unlike liquid crystal displays they do not require backlighting, which means they consume less energy. As it is the diodes themselves that emit coloured light, contrast and colour reproduction are better. The electroluminescent displays also offer a large viewing angle of almost 180 degrees. And because they require no backlighting, they can be very thin, making it possible to create entirely new shapes.
There are still several challenges to be met before OLEDs become firmly established on the market. ‘The main hurdle, as far as I’m concerned, is the high level of investment required to set up manufacturing,’ said Wedel. This is why, at least where lighting is concerned, he expects OLEDs to complement rather than replace conventional lighting devices. He added: ‘My vision is that the day will come when all we need do is switch ink cartridges in our printers in order to print out our own lighting devices.’
