Display device and method of manufacturing the same

A method of manufacturing a display device, the method comprising:

• forming a preliminary light transmission layer on a display panel layer;
• forming, on the preliminary light transmission layer, a mask layer defining an opening exposing a portion of an upper surface of the preliminary light transmission layer;
• forming a light transmission layer defining a plurality of trenches recessed in a first direction towards the display panel layer by dry-etching the preliminary light transmission layer, using the mask layer;
• and
• filling the plurality of trenches with a light blocking material,
• wherein the mask layer includes a first layer and a second layer, which is disposed on the first layer, and
• wherein a side surface of the first layer is recessed further in a second direction perpendicular to the first direction than a side surface of the first layer.