A liquid crystal display device 1 has a liquid crystal display panel 11 that includes an optical sensor element 4 and a protection plate 21 that protects the liquid crystal display panel 11. The protection plate 21 and the liquid crystal display panel 11 are arranged with an air layer 25 therebetween. Between the liquid crystal display panel 11 and the protection plate 21, lens arrays 23 and 24 that form an image with light emitted from the liquid crystal display panel 11 as an erect image on a surface of the protection plate 21 and that forms, when an original 30 is placed on the protection plate 21, an image with reflected light of light irradiated onto the original 30 as an erect image on the optical sensor element 4 are provided. Thus, a display device having an image reading function that can protect the display panel and that can suppress lowering of resolution of a read out image and lowering of the display quality of a displayed image is provided.