Organic light emitting diode display including capping layer having optical thickness for improving optics

An organic light emitting diode (OLED) display, comprising:

• a first color pixel, a second color pixel, and a third color pixel on a substrate, each of the first, second, and third color pixels comprising:
• a first electrode disposed on the substrate;
• an organic emission layer disposed on the first electrode;
• a second electrode disposed on the organic emission layer;
• and
• a capping layer disposed on the second electrode,
• wherein:
• the first color pixel is configured to emit green light, and the second and third color pixels are each configured to emit a color of light other than green;
• the organic emission layer of the first color pixel comprises a lower first emission layer, an upper first emission layer, and a second emission layer each being configured to emit light;
• the organic emission layer of the second color pixel or the third color pixel comprises a third emission layer configured to emit light;
• the second emission layer and the third emission layer comprise both a host and a dopant;
• the lower first emission layer comprises the host, and does not comprise any dopants therein;
• the lower first emission layer of the first color pixel is disposed over the first electrode;
• the second emission layer of the first color pixel is disposed on the lower first emission layer of the first color pixel;
• and
• the upper first emission layer of the first color pixel is disposed on the second emission layer of the first color pixel.