Provided is a display apparatus. The display apparatus includes a display module configured to define a display surface on a plane. The display module includes a display panel having a plurality of display elements configured to display an image on the display surface and a pattern layer having a plurality of diffraction patterns arranged at an interval on the display panel. The diffraction patters are arranged to diffract at least a portion of incident light. At least a portion of the diffraction patterns has a width different from that of each of remaining diffraction patterns.