Bottom-emission organic electroluminescent display of high resolution and power saving
An organic electroluminescent display comprises a shadow layer, a transparent electrode, a light emitting layer, a reflective electrode and a cap layer formed on a substrate. The transparent electrode is connected to a transistor, located on the shadow layer, and has a larger area than the shadow layer. The cap layer is formed on the upper surface of the transparent electrode, and corresponds to the shadow layer. The light emitting layer is formed on the upper surface of the transparent electrode. And, the reflective electrode is formed on the upper surface of the light emitting layer.
1. A bottom-emission organic electroluminescent display having high pixel resolution wherein each pixel comprising:
a substrate;
a shadow layer disposed on the substrate;
a transparent electrode disposed on the shadow layer, and having a larger area than the shadow layer;
a cap layer disposed on the transparent electrode, wherein the cap layer has an aperture to expose a part of the transparent electrode, wherein the shadow layer is disposed in the aperture;
a light emitting layer disposed on the part of the transparent electrode for emitting light downward, wherein a part of the cap layer is in the aperture and interposed between the transparent electrode and the light emitting layer, and the part of the cap layer is overlapped with the shadow layer;
a reflective electrode disposed on the light emitting layer; and
a first transistor electrically connected to the transparent electrode.
2. The bottom-emission organic electroluminescent display of claim 1 , wherein the area of the substrate covered by the part of the cap layer in the aperture is equal to or smaller than that of the substrate covered by the shadow layer.
3. The bottom-emission organic electroluminescent display of claim 1 , wherein the shadow layer comprises a metal layer.
4. The bottom-emission organic electroluminescent display of claim 1 , wherein the shadow layer comprises a metal wire.
5. The bottom-emission organic electroluminescent display of claim 1 , wherein the shadow layer comprises a gate metal of a second transistor.
6. The bottom-emission organic electroluminescent display of claim 1 , wherein the shadow layer comprises a source metal of a second transistor.
7. The bottom-emission organic electroluminescent display of claim 1 , wherein the shadow layer comprises a drain metal of a second transistor.
8. The bottom-emission organic electroluminescent display of claim 1 , wherein the shadow layer comprises a capacitor.
9. The bottom-emission organic electroluminescent display of claim 1 , wherein the transparent electrode covers the transistor and the shadow layer.
10. The bottom-emission organic electroluminescent display of claim 1 , wherein the cap layer comprises an insulating pattern.
11. The bottom-emission organic electroluminescent display of claim 1 , further comprising a flat layer disposed between the transparent electrode and the shadow layer.