Embodiments of the disclosure are related to a display device, in a structure where an optical sensor is disposed on an opposite side of a side displaying an image and overlapping an active area of a display panel, as increasing a transmittance by implementing an area overlapping to the optical sensor as a low resolution area, a sensing function by the optical sensor located in the active area could be implemented. Furthermore, by implementing a number of a gate electrode or a width of a channel region or the like of a driving transistor disposed in the low resolution area to be different from those of a driving transistor disposed in a high resolution area, compensating a luminance of the low resolution area and preventing a deviation of a luminance between the low resolution area and the high resolution area can be achieved.