The present invention relates to efficient organic light emitting devices (OLEDs)
doped with multiple light-emitting dopants, at least one dopant comprising a phosphorescent
emitter, in a thin film emissive layer or layers. The present invention is directed
to an efficient phosphorescent organic light emitting device utilizing a plurality
of emissive dopants in an emissive region, wherein at least one of the dopants
is a phosphorescent material. Thus, the present invention provides an organic light
emitting device comprising an emissive region, wherein the emissive region comprises
a host material, and a plurality of emissive dopants, wherein the emissive region
is comprised of a plurality of bands and each emissive dopant is doped into a separate
band within the emissive region, and wherein at least one of the emissive dopants
emits light by phosphorescence.