Organic Light Emitting Element and Display Device Using the Element

A light-emitting device comprising:

• a first light-emitting element over a substrate;
• and
• a second light-emitting element over the substrate,
• wherein the first light-emitting element comprises a mixed region between a pair of electrodes,
• wherein the first light-emitting element comprises a material capable of emitting light from a triplet excitation state,
• wherein the second light-emitting element comprises a material capable of emitting light from a singlet excitation state,
• wherein the mixed region comprises the material capable of emitting light from the triplet excitation state, and
• wherein the material capable of emitting light from the triplet excitation state is a dopant.

A light-emitting device comprising:

• a first light-emitting element over a substrate;
• and
• a second light-emitting element over the substrate,
• wherein the first light-emitting element comprises a mixed region between a pair of electrodes,
• wherein the first light-emitting element comprises a material capable of emitting light from a triplet excitation state,
• wherein the second light-emitting element comprises a material capable of emitting light from a singlet excitation state,
• wherein the material capable of emitting light from the triplet excitation state includes an iridium complex exhibiting red color light emission,
• wherein the mixed region comprises the material capable of emitting light from the triplet excitation state, and
• wherein the material capable of emitting light from the triplet excitation state is a dopant.

A light-emitting device comprising:

• a first transistor over a substrate;
• a second transistor over the substrate;
• a first light-emitting element over the first transistor;
• and
• a second light-emitting element over the second transistor,
• wherein the first light-emitting element comprises a mixed region between a pair of electrodes,
• wherein the first light-emitting element comprises a material capable of emitting light from a triplet excitation state,
• wherein the second light-emitting element comprises a material capable of emitting light from a singlet excitation state,
• wherein the mixed region comprises the material capable of emitting light from the triplet excitation state, and
• wherein the material capable of emitting light from the triplet excitation state is a dopant.