An organic light-emitting display apparatus comprising: sub-pixel lines disposed in parallel, wherein the sub-pixel lines each arranged to emit light of a single colour and each comprise a plurality of sub-pixels disposed in a linear arrangement, the sub-pixel lines comprising: first and second edge sub-pixel lines (301, 302) disposed at opposing side edges of the apparatus; and centre sub-pixel lines disposed between the edge sub-pixel lines, wherein the external emission width of each of the edge sub-pixel lines, which is a width-wise distance along which light is emitted from a sub-pixel line and transmitted out of the display apparatus, is less than the external emission width of the centre sub-pixel lines that emit the same colour of light as the corresponding edge sub-pixel line, the organic light-emitting display apparatus further comprising: a substrate to support the sub-pixel lines; and opaque auxiliary electrode layers formed on the substrate and partially covering the edge sub-pixel lines, wherein the edge and centre sub-pixel lines comprise: pixel electrodes; organic light-emitting layers electrically connected to the pixel electrodes; and an opposite electrode disposed on the light-emitting layers, wherein the auxiliary electrode layers are formed on the opposite electrode, wherein the auxiliary electrode layers comprise a light blocking material, wherein the auxiliary electrode layers extend linearly along the lengths of the edge sub-pixel lines, and wherein the auxiliary electrode layers cover the outermost sides of the edge sub-pixel lines. sub-pixel lines disposed in parallel, wherein the sub-pixel lines each arranged to emit light of a single colour and each comprise a plurality of sub-pixels disposed in a linear arrangement, the sub-pixel lines comprising: first and second edge sub-pixel lines (301, 302) disposed at opposing side edges of the apparatus; and centre sub-pixel lines disposed between the edge sub-pixel lines, first and second edge sub-pixel lines (301, 302) disposed at opposing side edges of the apparatus; and centre sub-pixel lines disposed between the edge sub-pixel lines, wherein the external emission width of each of the edge sub-pixel lines, which is a width-wise distance along which light is emitted from a sub-pixel line and transmitted out of the display apparatus, is less than the external emission width of the centre sub-pixel lines that emit the same colour of light as the corresponding edge sub-pixel line, the organic light-emitting display apparatus further comprising: a substrate to support the sub-pixel lines; and opaque auxiliary electrode layers formed on the substrate and partially covering the edge sub-pixel lines, wherein the edge and centre sub-pixel lines comprise: pixel electrodes; organic light-emitting layers electrically connected to the pixel electrodes; and an opposite electrode disposed on the light-emitting layers, a substrate to support the sub-pixel lines; and opaque auxiliary electrode layers formed on the substrate and partially covering the edge sub-pixel lines, wherein the edge and centre sub-pixel lines comprise: pixel electrodes; organic light-emitting layers electrically connected to the pixel electrodes; and an opposite electrode disposed on the light-emitting layers, pixel electrodes; organic light-emitting layers electrically connected to the pixel electrodes; and an opposite electrode disposed on the light-emitting layers, wherein the auxiliary electrode layers are formed on the opposite electrode, wherein the auxiliary electrode layers comprise a light blocking material, wherein the auxiliary electrode layers extend linearly along the lengths of the edge sub-pixel lines, and wherein the auxiliary electrode layers cover the outermost sides of the edge sub-pixel lines.