A liquid crystal display device (display device) (100) of the present invention includes a display panel (20) provided with a plurality of light sensor elements, and has an area sensor function in which the plurality of light sensor elements detect an image on a surface of the liquid crystal display device, so as to determine a location of an input from outside. The liquid crystal display device includes (i) a front side polarizing plate (40) provided on or above a surface of the display panel (20) which surface is on an image display surface side and (ii) a λ/2 phase plate (50b) and a λ/4 phase plate (50a) which are stacked in this order on the front side polarizing plate (40) so that an optical axis (a slow axis) of the λ/2 phase plate (50b) and an optical axis (a slow axis) of the λ/4 phase plate (50a) intersect with each other. The phase plate formed by stacking the λ/2 phase plate (50b) and the λ/4 phase plate (50a) is referred to as a broadband λ/4 phase plate (50). This makes a light sensor equipped display device which (i) prevents a reflection of light coming from a display image and (ii) allows determination of an input location with higher accuracy.