Organic light emitting device

An organic light emitting device comprising:

• a first light emitting part on a substrate, emitting a first light of a first wavelength, wherein the first light emitting part includes a transparent anode in contact with the substrate, a first organic light emitting layer, and a transparent cathode corresponding to the transparent anode, which are sequentially stacked on the substrate, the cathode including a first surface facing the anode and a second surface opposite to the first surface;
• a second light emitting part on the first light emitting part, emitting a second light of a second wavelength, wherein the second light emitting part includes a transparent electrode, a second organic light emitting layer, and a reflective electrode sequentially stacked on the second surface of the cathode of the first light emitting part;
• and
• a fluorescent material disposed between the second surface of the cathode and the transparent electrode, wherein the fluorescent material receives the first and second lights and generates a third light of a third wavelength different from the first and second wavelengths.