A display device comprising: a first base substrate comprising a plurality of light transmitting areas and a light blocking area surrounding each of the light transmitting areas; a second base substrate disposed to be spaced apart from the first base substrate; a plurality of pixels (PXij) disposed between the first base substrate and the second substrate and respectively overlapping the light transmitting areas when viewed in a direction perpendicular to a major surface of the first base substrate; and first and second polarizers (PL1, PL2) spaced apart from each other such that the pixels are disposed therebetween, wherein the first polarizer comprises a plurality of optical conversion layers (LCL1, LCL2) disposed on different layers from each other, each of which comprises a plurality of lattice wires (WG1, WG2), wherein the plurality of optical conversion layers comprises: a first optical conversion layer including a first set of lattice wires; and a second optical conversion layer including a second set of lattice wires, wherein the second set of lattice wires are substantially parallel to the first set of lattice wires; a third optical conversion layer (LCL 10-20) including a third set of lattice wires extending in the same direction as the first set of lattice wires and being arranged in the same direction as the first set of lattice wires, wherein the first optical conversion layer comprises a polarization part including the first set of lattice wires, and the second optical conversion layer comprises a polarization part including the second set of lattice wires, wherein the polarization parts of the first and second optical conversion layers overlap with the light transmitting areas when viewed in the direction perpendicular to the major surface of the first base substrate, characterized in that each of the first and second sets of lattice wires comprises a metal layer and a metal oxide layer covering the metal layer, and in that the second optical conversion layer further comprises a reflection part that covers the light blocking area. a first base substrate comprising a plurality of light transmitting areas and a light blocking area surrounding each of the light transmitting areas; a second base substrate disposed to be spaced apart from the first base substrate; a plurality of pixels (PXij) disposed between the first base substrate and the second substrate and respectively overlapping the light transmitting areas when viewed in a direction perpendicular to a major surface of the first base substrate; and first and second polarizers (PL1, PL2) spaced apart from each other such that the pixels are disposed therebetween, wherein the first polarizer comprises a plurality of optical conversion layers (LCL1, LCL2) disposed on different layers from each other, each of which comprises a plurality of lattice wires (WG1, WG2), wherein the plurality of optical conversion layers comprises: a first optical conversion layer including a first set of lattice wires; and a second optical conversion layer including a second set of lattice wires, wherein the second set of lattice wires are substantially parallel to the first set of lattice wires; a third optical conversion layer (LCL 10-20) including a third set of lattice wires extending in the same direction as the first set of lattice wires and being arranged in the same direction as the first set of lattice wires, a first optical conversion layer including a first set of lattice wires; and a second optical conversion layer including a second set of lattice wires, wherein the second set of lattice wires are substantially parallel to the first set of lattice wires; a third optical conversion layer (LCL 10-20) including a third set of lattice wires extending in the same direction as the first set of lattice wires and being arranged in the same direction as the first set of lattice wires, wherein the first optical conversion layer comprises a polarization part including the first set of lattice wires, and the second optical conversion layer comprises a polarization part including the second set of lattice wires, wherein the polarization parts of the first and second optical conversion layers overlap with the light transmitting areas when viewed in the direction perpendicular to the major surface of the first base substrate, characterized in that each of the first and second sets of lattice wires comprises a metal layer and a metal oxide layer covering the metal layer, and in that the second optical conversion layer further comprises a reflection part that covers the light blocking area.