A display device comprising: a substrate provided with a first sub-pixel and a second sub-pixel; a first electrode (311, 312) provided in each of the first sub-pixel and the second sub-pixel; a third electrode (351, 352) provided on the first electrode (311, 312) in each of the first sub-pixel and the second sub-pixel; a second electrode (331, 332) provided between the first electrode (311, 312) and the third electrode (351, 352) in each of the first sub-pixel and the second sub-pixel; a first light emitting layer (321, 322) provided between the first electrode (311, 312) and the second electrode (331, 332) in each of the first sub-pixel and the second sub-pixel and adapted to emit light of a first color; a second light emitting layer (341, 342) provided between the second electrode (331, 332) and the third electrode (351, 352) in each of the first sub-pixel and the second sub-pixel and adapted to emit mixed light of second and third colors which are different from each other; a first driving transistor (211, 212) provided on the substrate in each of the first sub-pixel and the second sub-pixel, wherein the first driving transistor (211, 212) applies a first voltage to the first electrode (311, 312); a second driving transistor (221, 222) provided on the substrate in each of the first sub-pixel and the second sub-pixel, wherein the second driving transistor (221, 222) applies a second voltage to the third electrode (351, 352); an insulating film provided on the first driving transistor (211, 212) and the second driving transistor (221, 222), the insulating film having an opening area (OA1, OA2) partially exposing the second driving transistor (221, 222); and a mask pattern (261, 262) provided on the insulating film, wherein the mask pattern (261, 262) is provided at one side of the first sub-pixel or the second sub-pixel between the first sub-pixel and the second sub-pixel where the opening area (OA1, OA2) is arranged, is spaced apart from the first electrode (311, 312), and has a protrusion (261a, 262a) partially covering the opening area (OA1, OA2), wherein the first sub-pixel and the second sub-pixel are adapted to emit light of at least three colors, and wherein the third electrode (351, 352) is connected to the second driving transistor (221, 222) below the mask pattern (261, 262). a substrate provided with a first sub-pixel and a second sub-pixel; a first electrode (311, 312) provided in each of the first sub-pixel and the second sub-pixel; a third electrode (351, 352) provided on the first electrode (311, 312) in each of the first sub-pixel and the second sub-pixel; a second electrode (331, 332) provided between the first electrode (311, 312) and the third electrode (351, 352) in each of the first sub-pixel and the second sub-pixel; a first light emitting layer (321, 322) provided between the first electrode (311, 312) and the second electrode (331, 332) in each of the first sub-pixel and the second sub-pixel and adapted to emit light of a first color; a second light emitting layer (341, 342) provided between the second electrode (331, 332) and the third electrode (351, 352) in each of the first sub-pixel and the second sub-pixel and adapted to emit mixed light of second and third colors which are different from each other; a first driving transistor (211, 212) provided on the substrate in each of the first sub-pixel and the second sub-pixel, wherein the first driving transistor (211, 212) applies a first voltage to the first electrode (311, 312); a second driving transistor (221, 222) provided on the substrate in each of the first sub-pixel and the second sub-pixel, wherein the second driving transistor (221, 222) applies a second voltage to the third electrode (351, 352); an insulating film provided on the first driving transistor (211, 212) and the second driving transistor (221, 222), the insulating film having an opening area (OA1, OA2) partially exposing the second driving transistor (221, 222); and a mask pattern (261, 262) provided on the insulating film, wherein the mask pattern (261, 262) is provided at one side of the first sub-pixel or the second sub-pixel between the first sub-pixel and the second sub-pixel where the opening area (OA1, OA2) is arranged, is spaced apart from the first electrode (311, 312), and has a protrusion (261a, 262a) partially covering the opening area (OA1, OA2), wherein the first sub-pixel and the second sub-pixel are adapted to emit light of at least three colors, and wherein the third electrode (351, 352) is connected to the second driving transistor (221, 222) below the mask pattern (261, 262).