The display panel 150 may include a plurality of sub-pixels (SP). The plurality of sub-pixels may be formed in pixel regions defined by a plurality of gate lines and a plurality of data lines intersecting with one another.

A plurality of driving power lines are formed on the display panel 150. The plurality of driving power lines are formed in parallel to the plurality of data lines and supply driving power.

Each of the plurality of sub-pixels may be one of a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel.

One unit pixel which displays one image may include a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel adjacent to one another, or may include a red sub-pixel, a green sub-pixel, and a blue sub-pixel.

Each of the plurality of sub-pixels may include an OLED and a pixel circuit.

The OLED is connected between the pixel circuit and a second driving power line and emits predetermined color light by emitting light in proportion to a data current amount supplied from the pixel circuit.

To this end, the OLED includes an anode electrode (or a pixel electrode) connected to the pixel circuit, a cathode electrode (or a reflection electrode) connected to the second driving power line, and a light emitting cell formed between the anode electrode and the cathode electrode to emit light of one of red, green, blue, and white colors.