Two and a half years after its start, the European research project OLLA presents its second milestone: a prototype white Organic Light-Emitting Diode (OLED) light source, with an efficacy of 25 lumen per watt and a lifetime of over 5.000 hours from an initial brightness of 1.000 cd/m².

“This very efficient white OLED light tile was designed at
Philips from a mixture of fluorescent and phosphorescent
OLED materials within the NOVALED proprietary PIN
structure. It contains several layers of specially designed
materials from OLLA partners, and highlights the results of
two years of excellent teamwork between the material and
device partners within the project,’’ Visser continues.
"The lifetime achievement of 5000 hours in combination with high efficiency is a very important step towards the introduction of OLED technology in lighting applications," said Karsten Diekmann from OSRAM Opto Semiconductors, partner in the project. He pointed out the
capability of OLEDs for applications such as signage or LCD backlighting.

The project further evaluates several fabrication processes for OLED fabrication. Last December,
the project showed Europe’s largest OLED light tile at the IST event in Helsinki: an OLED lamp
consisting of four 15x15cm2 OLED tiles. “These large OLED tiles are fabricated on ourevaporation tools in Dresden“Jörg Amelung of Fraunhofer-IPMS said “This proves the possibility
to fabricate large OLED tiles and in the next months we will transfer the new efficient OLED stack
towards our tools, so that we also can demonstrate this record on large substrates.“
press release


Initial tests of the OLLA demonstrator OLED tile in glove box under nitrogen atmosphere.
This demonstrator is fabricated on the inline OMBD tool at Fraunhofer-IPMS in Dresden.
(Picture source: Fraunhofer IPMS )

Organic LEDs can be made in various colors (including warm and cold whites)
with very high color rendering index
(picture source: the OLLA project)