Fraunhofer

The Fraunhofer Institute for Laser Technology (ILT) is developing a new cost-efficient process for applying conductor paths to OLEDs. The new process also makes homogeneous luminosity for the OLED panels, thanks to micro-scale conductor paths.

When you make OLEDs, you apply metallic conductor paths to the anode layer (ITO - Indium Tin Oxide - or similar materials). The size of these conductor paths plays an important role here: if they are too wide the paths can affect the luminous homogeneity of the light source. Today the metallic conductor material has been applied to the OLED surface using a vacuum sputter process which is energy intensive, has up to 90% material loss and is expensive. It is also not environmental friendly as it uses metals that has to be disposed of after use. The conduct paths are wide, and so disrupt the homogeneous luminosity of the OLEDs.

NEMO (NEw Materials for OLEDs) is a new EU project focusing on new emitting systems based on soluble small molecules with long lifetime and efficiency. NEMO is led be four companies (coordinated by Merck) and seven research and academic institutions (including the Fraunhofer institute). The project is scheduled to last for 2.5 years, and is funded by the German government with 32 million euros.

Via EE Times

Zumbotel Group from Austria and the Fraunhofer IPMS institute has agreed to create a new joint-venture for the development and production of OLED lighting modules. The new company will be called Ledon OLED Lighting. It will be based in Dresden, and will have 10-15 employees in the first year.

Large Area OLED lighting panel,Fraunhofer

Ledon will not only produce OLED panels, but will also develop and manufacture complete OLED lighting solutions and concepts for large-scale OLED systems. Ledon will use the Fraunhofer's pilot line, to make OLED panels on 370x470 mm2 substrates with a cycle time of just three minutes. 

Back in January 2009 we have interviewed Prof. karl Leo from the Fruanhofer IPMS, and he explains their technology and aims.

The HYPOLED project (High-Performance OLED-Microdisplays for Mobile Multimedia HMD and Projection Applications) is now in month 18, and they present some intermediate results:

• A new all-digital VGA full-color OLED microdisplay backplane has been designed by Fraunhofer IPMS in a 0.18 micrometer commercial CMOS process and is currently under prototype manufacturing.
• Pico-projector optics (matching HYPOLED VGA microdisplay) has been developed by Fraunhofer IOF and publicly demonstrated.
• The MediaBox connectivity to DVB-T, DVB-H (MPEG-2/4 streaming) and WiFi has been implemented by Fraunhofer IPMS on a low-power multimedia processor platform (Samsung S3C6400) and has been demonstrated.

HYPOLED was originally founded and co-ordinated by MicroEmissive Displays (MED) and the Fraunhofer IPMS. But MED has entered administration, and now they are collaborating with MicroOLED, who joined the team in March 2009. The collaboration targets benchmarking of MicroOLED's existing WVGA and Fraunhofer IPMS' HYPOLED VGA backplane, each in combination with both MicroOLED's and Fraunhofer IPMS' pin OLED stacks.

A couple of month ago, the Fraunhofer institute has shown their interactive data eyeglasses. These glasses include an OLED microdisplay on a CMOS chip that also includes an eye tracker. They now say that such devices could be ready within 2 years.

More information on the OLED device can be found here. Basically, the idea is a bi-directional OLED - which is a display and a camera in one chip. They put photo-diodes between the OLED pixels.

OLED is an emissive display technology - it means that the OLED materials emit light. This is in contrast to a reflective display - which uses an external light source - an ePaper display for example, or a 'real' paper. OLEDs are bright, and provide great image quality, but because they are emissive, when viewed under direct sunlight (or any strong light source) they have a readability problem.

The best display technology for direct sunlight (besides ePaper) is said to be transflective LCDs, which uses a reflective layer under the LCD's filter. However this reduces the transmissive capabilities of the LCD, and the contrast is compromised as well. With OLEDs, unfortunately, it's not possible to use a reflective layer as the OLEDs themselves emit light.

We have received some word from Nokia N85 users saying that the display is not readable in sunlight - it behaves very poorly. It seems this issue is widespread. Check out this photo for example, showing a prototype N85 outside:

Here's a short video showing the Samsung Omnia II outside. As you can see, the contrast is very poor. In this case they use the automatic brightness mode.

The OLED100.eu project is a European 3-year OLED lighting project. The 30M$ project is a followup to the OLLA project, ended in June 2008, and it is lead by Philips, OSRAM, Siemens, Novaled and the Franhofer IPMS.

Dr. Stefan Grabowsky, the project's manager has been kind enough to talk to us, answer a few questions and give us more info on the project. Dr. Stefan has a Ph.D in Physics,  from the University of Duisburg. In 2000 he joined Philips Research labs. He's working on OLEDs for several years now, with a focus on device physics and OLED stack development. Since September 2008 he is the project manager for OLED100.eu.

Q: Stefan, thanks for taking the time to do this interview. Can you tell us a bit about OLED100.eu?
OLED100.eu is an European integrated research project that has brought together a consortium of experts from leading industry and academic organizations to accelerate the development of organic light-emitting diode (OLED) technologies. It has received €12.5 million funding from the European Community’s Seventh Framework Programme to form the technological basis for efficient OLED applications for the general lighting industry in Europe.

Large-area OLED from Philips