Organic light emitting display

An organic light emitting display comprising:

• a scan driver for supplying
• a first scan signal to first scan lines,
• a second scan signal to second scan lines, and
• emission control signals to emission control lines;
• a data driver for supplying data signals to data lines;
• an initial power source line coupled to an initial power source;
• a bias power source line coupled to a bias, power source having a different voltage from that of the initial power source;
• pixels at crossing regions of the data lines and horizontal power source lines extending in parallel with and corresponding to the first scan lines, the horizontal power source lines being configured to couple the pixels to the initial power source and the bias power source, each of the pixels comprising a driving transistor for controlling an amount of current that flows from a first power source to an organic light emitting diode (OLED) in accordance with one of the data signals;
• first switching elements coupled between the horizontal power source lines and the initial power source line, each of the first switching elements comprising one terminal connected to one of the horizontal power source lines and another terminal connected to the initial power source line;
• and
• second switching elements coupled between the horizontal power source lines and the bias power source line, the second switching elements being configured to alternately turn on and off with the first switching elements, each of the second switching elements comprising one terminal connected to one of the horizontal power source lines and another terminal connected to the bias power source line.