Fraunhofer - Page 11

LEDON is showing their first OLED lighting modules prototypes. There are two series, the LUREON and the LUCEOS. The LUREON consists on rectangular OLED modules, fabricated in cooperation with the Fraunhofer IPMS, with element dimensions of 100x100 and 100x50 mm², which can be easily combined to large area lighting by an
integrated electrical bus system. The LUCEOS module series offers a hexagonal
module system based on Osram's ORBEOS CDW-031 OLEDs.

LEDON OLED Lighting modules photo

LEDON say that the modules include an electrical and data bus system for maximum flexibility in large areas. The system bus can be configured to support DALI or DMX bus systems and allows the simple and robust connection between the different sub elements.

LEDON OLED Lighting was created back in 2009 as a joint-venture between the Fraunhofer Institute and Zumtobel.

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.

The Fraunhofer ILT is now developing a laser technique to apply
micro-scale conductor paths for the industrial partner Philips. A mask
foil is placed on the surface of the conductor which represents the
negative to the conductor path geometry later required. This is then
covered by a donor foil whose material will constitute the conductor
path, for example aluminum or copper. The assembly is fixed in place
and hit with laser radiation traveling at a speed of up to 2.5 m/s
along the mask geometry. A mixture of melt drops and vapor forms, which
is transferred from the donor foil to the substrate. The solidified
mixture produces the conductor path, whose geometry is determined by
the mask. As the process takes place in the ambient atmosphere an
expensive process chamber is not required. There is no material loss
because the residual material of the donor foil can be re-used.

More information here

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.

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 - which means that it emits its own light, in contrast to a reflective display - which uses an external light source - an ePaper display for example, or an LCD which is a display that blocks light from a backlight unit.

OLEDs are bright, and provide great image quality, and as of 2021, these displays perform very well under direct sunlight.

But this was not always the case. In early AMOLED displays, sunlight readability was very poor. The 2008 Nokia N85 for example, one of the first products with AMOLED displays, behaved very poorly in direct sunlight, as can be seen in the image below:

The problem in early AMOLED displays resulted from reflectance from metal electrodes in addition to relatively low brightness. Display makers however, soon upgraded their OLED displays to increase performance. Helped by new technologies and materials, OLED displays quickly overcame the sunlight readability problem. Today OLED displays actually perform better than the best LCDs in direct sunlight.

For more information on OLED display technology click here.

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

The Fraunhofer IPMS Institute is working towards autostereoscopic 3D displays that use OLEDs as patterened backlight. They are showing a 3.5" 3D QVGA display, that uses a 80x60mm OLED backlight. 

The OLEDs are using Novaled's PIN-OLED tech, and are capable of either monochrome-green of full color.

The Fraunhofer IMPS's new bi-directional OLED microdisplay packs an OLED display and a camera in the same chip. This can be used for a lot of applications - from automotive ('gaze' monitoring for safety) to medicine, security, see-through HMDs, and just fun gadgets... The Fraunhofer showed us a demo interactive-eyeglasses just a couple of days ago. Now we got some more info on that chip...

The OLED is an Active-Matrix one, with 320x240 resolution, 8bit color level. The Peak luminance is less than 11,000cd/m2, and the efficiency is  5.3cd/A@500cd/m2.

The camera matrix is build from photodiodes, placed just between the OLED pixels.