OLEDs adapted as 'ultrathin' large area backlights

04 Oct 2012

German partners BMG MIS and Fraunhofer COMEDD present first results of the project So-Light.

The use of organic light-emitting diodes in several new special fields of application is under investigation by a consortium of eleven project partners within the project “So-Light“ (funded by the German Federal Ministry of Education and Research BMBF). Now, the first examples are available and will make their debut at the Fraunhofer COMEDD booth at the Plastic Electronics 2012 show in Dresden, Germany, betwen 9-11 October.

The project partner BMG MIS is manufacturer of large area display systems. There is great interest in display systems with minimum installation depth. Since OLEDs can be evaporated on very thin glass, they offer a high potential for backlight illumination for LCD-based systems. Now the availability of large area and homogeneously emitting OLEDs enables ultrathin LCD OLED compounds as basis for modular installations of large area LCD display systems.

In contrast to conventional backlight illumination, reflector- and fiber optic components will no longer be required for those modular systems and thus the system design will be considerably simplified. Furthermore, OLEDs create a very comfortable and homogeneous light.

The Fraunhofer COMEDD developed and manufactured appropriate OLEDs for those displays together with BMG MIS. The first technology demonstrator, which shows the principle of the LCD-backlight illumination, will first be publicly presented at the Plastic Electronics Show 2012 .

The demonstrator is backlit by three tiled OLED-modules with the dimensions of 300 mm x 100 mm each. Due to the small total installation depth of 30 mm, it achieves a pixel brightness of 350 cd/m², which is certainly sufficient for indoor applications.

In the long term the further development of the current OLED area light sources to a single, coherent and maximized area (ideally matching the size of the LCD) offers potential for installation depths of less than 10 mm. These display systems can be used for example in passenger information systems in public transportation, in central building control systems and many more applications.

Dr. Konrad Crämer, head of the department for organic technologies, says he is optimistic: “Fraunhofer COMEDDD was able to produce the OLEDs for the backlight illumination of the LCDs within the project. In order to achieve even thinner systems, we are intensifying our work on the manufacturing of OLEDs on foils, which will be flexible as well.” The project partners would like to thank the German Federal Ministry of Education and Research for the support of the project So-Light (project reference number 13N105533).

Further OLED-exhibits, such as interactive data eyeglasses with OLED microdisplays, a makeup-mirror illuminated by OLEDs (in cooperation with HELLA within the project So-Light)) and dynamic OLED lighting will be presented at the Fraunhofer COMEDD booth.

About the Author

Matthew Peach is a contributing editor to optics.org