Display device

A display device comprising:

• a substrate including a display area and a peripheral area around the display area;
• a thin-film transistor disposed on the substrate in the display area and a display element electrically connected to the thin-film transistor;
• and
• a first voltage line and a second voltage line located on the substrate in the peripheral area and supplying power to drive the display element,
• wherein the first voltage line is a common voltage line and entirely surrounds the display area,
• the second voltage line is a driving voltage line and is disposed to correspond to one side of the display area, and
• the first voltage line and the second voltage line are disposed on different layers.

A display device comprising:

• a substrate including a display area and a peripheral area around the display area;
• a pixel circuit located on the substrate in the display area and an organic light-emitting device electrically connected to the pixel circuit;
• a first voltage line located on the substrate in the peripheral area and applying a common voltage to the organic light-emitting device;
• and
• a driving circuit unit located on the substrate in the peripheral area and disposed between the first voltage line and the pixel circuit, and transmitting an electric signal to the display area,
• wherein the driving circuit unit is covered by a first insulating layer disposed over the display area and the peripheral area, and
• the first voltage line entirely surrounds the display area and has equal material and structure as a wire on the first insulating layer of the display area.