Organic light-emitting device

An organic light-emitting device comprising:

• a first sub-pixel, a second sub-pixel, and a third sub-pixel on a substrate;
• a plurality of first electrodes in the first sub-pixel, the second sub-pixel, and the third sub-pixel, respectively;
• a second electrode being a sub-common layer to the first sub-pixel and the second sub-pixel and facing the first electrodes of the first sub-pixel and the second sub-pixel;
• a third electrode in the third sub-pixel and facing the first electrode of the third sub-pixel;
• and
• an organic layer comprising a first emission unit between the first electrode and the second electrode of the first sub-pixel and configured to emit a light of a first color, a second emission unit between the first electrode and the second electrode of the second sub-pixel and configured to emit a light of a second color, and a third emission unit between the first electrode and the third electrode of the third sub-pixel and configured to emit a light of a third color,
• wherein the light of the third color is blue light, and a mixed light comprising the light of the first color, the light of the second color, and the light of the third color is white light, and
• i) the second electrode is substantially free of magnesium (Mg) and the third electrode comprises magnesium (Mg);
• or ii) the second electrode and the third electrode both include magnesium (Mg) according to Formula 1:
• Con2(Mg)<Con3(Mg) Formula 1
• wherein, in Formula 1:
• Con2(Mg) is a ratio, by percent, of a volume of magnesium (Mg) in the second electrode to a total volume of the second electrode, and
• Con3(Mg) is a ratio, by percent, of a volume of magnesium (Mg) in the third electrode to a volume of the third electrode.