Organic light-emitting diode display device having deep and sky blue sub-pixels
Provided is an organic light-emitting diode (OLED) display device having sub-pixels with four colors. When a B 1 sub-pixel that represents deep blue and a B 2 sub-pixel that represents sky blue are formed, by using a high efficiency blue organic material to form the same emission material layers in both the B 1 and B 2 sub-pixels such that a microcavity effect is implemented only in the B 2 sub-pixel and a sky blue peak is extracted from the high efficiency blue organic material of the B 2 sub-pixel, the emission material layer of the B 2 sub-pixel represents sky blue. Therefore, a process of depositing emission material layers is simplified, which leads to a short process time and a reduction of the cost of materials, resulting in improvement in process efficiency of the OLED display device.
1. An organic light-emitting diode (OLED) display device in which a red sub-pixel, a green sub-pixel, a deep blue sub-pixel, and a sky blue sub-pixel form a pixel, comprising:
an organic light-emitting layer in which the red sub-pixel includes a red light-emitting material layer, the green sub-pixel includes a green light-emitting layer, and the deep blue sub-pixel and the sky blue sub-pixel include the same blue light-emitting material layers; and
an organic light-emitting diode including a first electrode and a second electrode for each sub-pixel,
wherein the first electrode of the sky blue sub-pixel includes a reflection layer, the second electrode of the sky blue sub-pixel is semi-transparent, and the sky blue sub-pixel represents sky blue through a microcavity effect.
2. The OLED display device according to claim 1 , wherein the blue light-emitting material layer has a deep blue peak and a light blue peak, and a sky blue peak is extracted from the blue light-emitting material layer by the microcavity effect.
3. The OLED display device according to claim 1 , wherein the microcavity effect is implemented due to the blue light-emitting material layers or peripheral layers of the sky blue sub-pixel having different thickness combinations from the red sub-pixel, the green sub-pixel, and the deep blue sub-pixel.
4. The OLED display device according to claim 3 , wherein the peripheral layers comprise a hole transport layer and a hole injection layer between the blue light-emitting material layer and the first electrode, and an electron transport layer and an electron injection layer between the blue light-emitting material layer and the second electrode.
5. The OLED display device according to claim 1 , wherein the first electrodes of the red sub-pixel and the green sub-pixel comprise reflection layers, and the second electrodes are semi-transparent.
6. The OLED display device according to claim 1 , wherein the deep blue sub-pixel or the sky blue sub-pixel have two or three times the areas of the red sub-pixel and the green sub-pixels.