A display device comprising: a housing including a plurality of first fixing parts located on a first side wall of a bottom cover, and a plurality of second fixing parts located on a second side wall of a bottom cover, the first and second side walls (321, 322) being opposite sides; a plurality of light sources; at least one optical sheet disposed on the plurality of light sources; and a display panel having a plurality of electrodes and pixels disposed on the at least one optical sheet, the at least one optical sheet including: a plurality of first holes formed on a first side of the at least one optical sheet, the plurality of first holes having a rectangular shape; and a plurality of second holes formed on a second side of the at least one optical sheet, the plurality of second holes having a rectangular shape, the first and second sides (255, 256) being opposite sides of the at least one optical sheet, wherein the fixing parts of the bottom cover correspond to the holes of the at least one optical sheet, respectively, to couple the at least one optical sheet to the bottom cover, characterized in that, the plurality of first holes are asymmetrically arranged with respect to the positions of the plurality of second holes, wherein the size of a hole positioned at a central portion of the first side is smaller than the size of a hole positioned at an edge of the first side, wherein the length of a longer axis of the hole positioned at the central portion of the first side is shorter than the length of a longer axis of the hole positioned at the edge of the first side and the length of a longer axis of at least one of the plurality of second holes, and wherein the length of a shorter axis of the hole positioned at the central portion of the first side is substantially equal to the length of a shorter axis of the hole positioned at the edge of the first side and the length of a shorter axis of the hole positioned at the central portion of the first side is shorter than the length of a shorter axis of at least one of the plurality of second holes. a housing including a plurality of first fixing parts located on a first side wall of a bottom cover, and a plurality of second fixing parts located on a second side wall of a bottom cover, the first and second side walls (321, 322) being opposite sides; a plurality of light sources; at least one optical sheet disposed on the plurality of light sources; and a display panel having a plurality of electrodes and pixels disposed on the at least one optical sheet, a plurality of first holes formed on a first side of the at least one optical sheet, the plurality of first holes having a rectangular shape; and a plurality of second holes formed on a second side of the at least one optical sheet, the plurality of second holes having a rectangular shape, the first and second sides (255, 256) being opposite sides of the at least one optical sheet, the plurality of first holes are asymmetrically arranged with respect to the positions of the plurality of second holes, wherein the size of a hole positioned at a central portion of the first side is smaller than the size of a hole positioned at an edge of the first side, wherein the length of a longer axis of the hole positioned at the central portion of the first side is shorter than the length of a longer axis of the hole positioned at the edge of the first side and the length of a longer axis of at least one of the plurality of second holes, and wherein the length of a shorter axis of the hole positioned at the central portion of the first side is substantially equal to the length of a shorter axis of the hole positioned at the edge of the first side and the length of a shorter axis of the hole positioned at the central portion of the first side is shorter than the length of a shorter axis of at least one of the plurality of second holes.