OLEDs 

More money is earned these days with LCD flatscreens than with classical tube displays. But OLEDs (organic light-emitting diodes) are an alternative technology with full video capability. Market research institutes believe that there will be sales of two billion dollars with OLED displays in 2006. 

The Fraunhofer Material and Components Group is joining forces with the Fraunhofer Microelectronics Group to develop the technologies for manufacturing indicators and small polymerbased displays. The films of polymer materials have to be applied as thin and homogenous as possible, electrodes have to be deposited and encapsulation techniques devised that protect displays from environmental influences. 

First and foremost, polymers have to have a very uniform structure and be free of impurities to guarantee long life. There are only a few manufacturers in the world that master the large-scale synthesis of these materials. Furthermore, quality is often not satisfactory or materials cannot be produced in sufficient quantities. 

Flexible OLED (© Fraunhofer IAP, A. Okulla)

Fraunhofer IAP is capable of manufacturing these materials at the right amounts and with the required purity. They carry out all of the production processes right up to buildingsample displays in clean rooms since the lightemitting films are extremely thin and any particle of dust may cause the component to fail. 

These displays are available in a variety of colors (red, green, blue, and white) and have sufficient brightness and outstanding radiation characteristic. This means that these organic displays, in contrast to LCDs, will retain their color impression to visual angles of almost 180°.