OLED Q&A with Prof. Karl Leo - Institute Director of the Fraunhofer IPMS

I recently had the chance to talk with the nice guys over the Fraunhofer IPMS in Germany, and the Institute Director (Prof Karl Leo) have agreed to do a short interview and talk about their OLED program.

These guys have been working on OLED since 2000, now organized under the name Center for Organic Materials and Electronics Devices Dresden (COMEDD). COMEDD's aim is to do not only research, but also pilot fabrication. More on COMEDD here.

Prof. Dr. Karl Leo, since 1993, is full professor of optoelectronics at the Technische Universität Dresden and starting 2007 institute director of the Fraunhofer IPMS. Additionally he is one of the founders of the Spin-Off Novaled AG.

Q: Last month you opened the COMEDD in Dresden, where OLED lighting and display products will be researched and also produced. How was the first month in the center?
The main activity was the setup of the fabrication lines and the starting of the processing on these lines. Actually, we started in January the process installation on the Gen2 fabrication line so we expect to show first real devices pretty soon.

COMEDD Gen 2 fabrication lineCOMEDD Gen 2 fabrication line

Q: Do you really believe COMEDD can be an OLED production center? Will you compete with Korea, China and Japan?
The COMEDD lines are intended and designed for pilot production and to accelerate the possibility to scale up the production to larger volumes. At Fraunhofer, we believe that only if we establish also some production volume in Europe we will win the competition against other regions in the world. For OLED displays this was not possible, unfortunately. We cannot live from design alone. We also believe that the OLED lighting market with its strong segmentation and customer-specific designs is a market where Europe will have a much better competitive edge, compared to displays.

Q: You were working on micro-displays together with MED, which has recently closed its operations. How will that effect your microdisplays project?
Of course the closing of operations of Microemissive Display was a setback . Together with MED we had started and lead the European funded research project HYPOLED, directed towards the development of the next generation microdisplay technology for HMD and micro-projection applications. Currently we are in discussion about steps to support restructuring of MED and re-organizing the HYPOLED project, including possible introduction of a new partner.

Bidirectional OLED microdisplay by Fraunhofer IPMSBidirectional OLED microdisplay by Fraunhofer IPMS

Q: I think you are more involved now on OLED lighting rather than displays. Is that correct? Do you believe it has a greater potential?
Yes, that's correct, we see tremendous opportunities in OLED lighting for the future. Especially as a European research institute we see more possibilities in lighting solutions because the lighting industry in Europe is still strong. So we have to keep the business in Europe by strengthening the industry through future lighting solutions.

Q: What are your thoughts regarding OLEDs for TVs?
Of course the technical benefits of OLED-TVs in relation to LCD or Plasma-TVs are obvious but the cost competition is very hard. To win this competition the fabrication infrastructure for OLEDs has to be improved. Large Asian manufactures are on the way to setup the large area production, we hope and believe that they will succeed in setting up a price competitive fabrication.

Q: You have shown roll-to-roll manufacturing of OLED lighting panels... but haven't updated on it for a while. Do you work on other methods?
The roll-to-roll manufacturing tool is currently under installation and we plan to show first panels this year. Nevertheless, there is still a long way to go to roll-to-roll manufacturing since the tool concepts have not matured yet. We see roll-to-roll manufacturing as the most important technology to achieve competitive costs for general lighting, and also for organic solar-cell solutions.

Roll-To-Roll OLED/OPV manufacturing toolRoll-To-Roll OLED/OPV manufacturing tool

Q: Are you working on Polymer-based OLEDs (PLEDs)?
We are focused on small-molecule solutions because the device parameters are currently well above the polymer based OLEDs. Additionally, the process parameters can be more accurately controlled than using wet processing solutions. The cost benefit of solution based systems, which is often stated, is not really visible for us at this time: the main cost driver for large area solution is the material price, not the deposition method. The only benefit of solution based processes is in the field of patterning by using ink-jet methods, but this is for lighting solutions not relevant. In the mid- to long-term future, things might change, and we would not really see a problem to incorporate wet processing steps into our process.

Q: In October 2008 you showed a touch-controller based on OLEDs. This is a novel idea, can you update us on this project?
We received a lot of interesting feedback based on this demonstrator we have shown firstly on the Plastic Electronics 2008 in Berlin. We are working on the electronics to realize new solutions, we will announce this in the future.

Touch-OLED fabricated by Fraunhofer IPMS/COMEDDTouch-OLED fabricated by Fraunhofer IPMS/COMEDD

Q: Back in 2006 you constructed transparent OLED displays. Are you still working on those?
Yes, transparent displays but also signage solutions are very interesting technical solutions for novel display, signage, and lighting concepts. Currently we are working on this within the German funded project CARO (Car-OLED) together with industrial (Optrex Europe GmBH and Novaled AG) and academic partners. The aim is to show highly transparent systems combined with high reliability for automotive and industrial solutions.

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Posted: Jan 26,2009 by Ron Mertens