Provided is an array substrate, a photomask, and a display device. The array substrate includes a substrate, a common electrode layer on which a plurality of first via holes are provided at predetermined positions, a passivation layer having a plurality of second via holes disposed concentrically with the first via holes, and a pixel electrode layer having a plurality of pixel electrodes. Areas of the first via holes are configured to gradually decrease in the direction from an output proximal end to an output distal end of a gate line.