Active matrix substrate and organic EL display device

An active matrix substrate driven by an analog gray scale method, comprising:

• a substrate,
• an organic EL element,
• a power source line,
• a transistor that supplies current to the organic EL element from the power source line, and
• a compensation circuit for compensating variability of the threshold voltage in the transistor,
• wherein the organic EL element has a pixel electrode electrically connected to the transistor,
• a gate electrode of the transistor is provided in a first wiring layer and a second wiring layer,
• a portion of the gate electrode in the first wiring layer is covered with the pixel electrode,
• a portion of the gate electrode in the second wiring layer covers the power source line,
• the portions of the gate electrode in the first wiring layer and the second wiring layer are connected via a contact hole provided in an insulating layer,
• the first wiring layer is a layer closer to the substrate than the second wiring layer, and
• the second wiring layer is a layer closer to the substrate than the pixel electrode.