Even when a light shielding film is provided between a transistor and a substrate, a threshold voltage of the transistor can be prevented or suppressed from being shifted. A display device includes light shielding films provided between a substrate and a semiconductor layer of a transistor including a gate electrode and the semiconductor layer. The semiconductor layer includes a source region and a drain region. Both of the light shielding films overlap the semiconductor layer when seen in a plan view, and are spaced apart from each other in a direction.

Disclosed is a thin film transistor array comprising a substrate, a first thin film transistor on the substrate, and a second thin film transistor on the substrate, wherein the first thin film transistor includes a first active layer including an oxide semiconductor on the substrate, the first active layer includes a first channel portion, a first conductor portion, and a first middle portion between the first channel portion and the first conductor portion, the second thin film transistor includes a second active layer including an oxide semiconductor on the substrate, the second active layer includes a second channel portion, a second conductor portion, and a second middle portion between the second channel portion and the second conductor portion, and resistivity of the first conductor portion of the first thin film transistor is greater than resistivity of the second conductor portion of the second thin film transistor.