Array substrate and detection method thereof and display device

The invention discloses an array substrate and a detection method thereof and a display device. The array substrate comprises an underlayer substrate, a thin film transistor located on the underlayer substrate and a photosensitive layer located on the underlayer substrate; the photosensitive layer comprises a shading part, at least part of orthographic projection, on the underlayer substrate, of the figure of the shading part blocks the figure of an active layer of the thin film transistor, and the shading part is located on the side, deviating from a grid electrode, of the active layer of the thin film transistor. According to the array substrate, the shading part in the photosensitive layer is adopted for blocking the figure of the active layer, due to the fact that the photosensitive layer is illuminated with light rays, a photo-generated current can be generated, that is to say, the photosensitive layer can convert light energy into electric energy, the photosensitive layer has the certain light absorption effect, most of the light rays are absorbed by the photosensitive layer, light reflection of the shading part is reduced, and the influence on the display effect of the display device is reduced.