Organic light emitting diode display device and method for sensing pixel current therein

The present invention relates to an organic light emitting diode (OLED) display device capable of operating in a driving mode and a sensing mode, the sensing mode senses a driving current of each pixel and compensates for a luminance deviation between pixels due to pixel deterioration that occurs after shipping the device. The OLED device includes a display panel comprising a plurality of pixels P1, P2 that share a reference line RLm through which a reference signal is supplied; each pixel is respectively connected to a data line DLn, DLn+1. The data lines connect to a data driver (20) which drives the pixels in a time division manner through the data lines and senses currents of the driving TFT DT of each pixel as voltages through the reference line. In one embodiment the display panel comprises half as many reference lines as data lines, having fewer reference lines increases the aperture ratio of the panel.