High efficiency multi-color electro-phosphorescent OLEDs

An organic light emitting device comprising an anode, a cathode and an emissive region, wherein the emissive region is located between the anode and the cathode and the emissive region comprises

• a host material, and
• a plurality of emissive dopants,
• wherein the emissive region is comprised of two or three bands and each emissive dopant is doped into a separate band within the emissive region, and wherein at least two of the emissive dopants emit light by phosphorescence from a triplet molecular excited state.

An organic light emitting device comprising an anode, a cathode and an emissive region, wherein the emissive region is located between the anode and the cathode and 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 from a triplet molecular excited state, and wherein a combined emission of the plurality of emissive dopants sufficiently spans the visible spectrum to give a white emission.