OLED devices are disclosed having increased external electroluminescence quantum
efficiencies, i.e., increased "out-coupling" efficiencies. OLED devices that have
increased out-coupling efficiencies and that are also protected from environmental
elements such as moisture and oxygen are also disclosed. The OLED device of the
present invention comprises a substrate; an active region positioned on the substrate,
wherein the active region comprises an anode layer, a cathode layer and a light-emitting
layer disposed between the anode layer and the cathode layer; and a polymeric layer
disposed (a) over the active region, (b) under the active region or (c) both over
and under the active region. The polymeric layer has microparticles incorporated
therein, and the microparticles are effective to increase the out-coupling efficiency
of the OLED. In one embodiment, the OLED device comprises a composite barrier layer
and the microparticles are incorporated in a polymeric planarizing sublayer of
the composite barrier layer. The composite barrier layer in this embodiment also
protects the OLED from damage caused by environmental elements such as moisture
and/or oxygen.