OSRAM has developed a transparent white OLED with outstanding performance. The large-scale prototype is transparent either on or off. Under laboratory conditions
it has achieved a luminous efficacy of more than 20 lm/W and a brightness of 1000 cd/m². This opens up possible applications such as partitions that are almost invisible by day and then provide a pleasant diffused light at night.
The prototype of the transparent white OLED tile with color coordinates 0.396/0.404 (CIEx/y main emissive side) lights up over an area of almost 90 cm². At present, the transparence of the OLED is 55%. As the product is further developed this value is expected to rise to 75%. The relative strengths of the beams in the two hemispheres can be adjusted within a wide range. This means that a surface light source installed for example in furniture or on a canopy can be configured so that light shines only in the required direction. The results were achieved as part of BMBF project OPAL2008 (Germany Ministry for Education and Research, organic light emitting diodes for illumination applications).
Visions of a bright future
OLED are complementary to most existing light sources and will open up entirely new areas of application. They are already inspiring designers and will be enriching the market for premium designer luminaires in the near future. At a later date we expect to see revolutionary changes to the entire lighting market. Visions of the future include illuminated partitions and canopies, and the integration of these light sources in a wide variety of applications on the general lighting market to create a special atmosphere.