Optical film and electronic device including the same

A backlight unit comprising:

• a light source for emitting a light to a first direction;
• a light guide plate wherein the light source is located at a side of the light guide plate;
• and
• an optical film comprising:
• a matte layer including a plurality of protrusions protruded toward to a viewing direction and disposed on a first base film;
• a light blocking pattern layer disposed under the first base film and including a plurality of light absorption patterns, wherein each of the plurality of light absorption patterns includes an upper surface facing the first base film, a lower surface opposite to the upper surface extended in a second direction which is substantially parallel to the first direction, and a side surface extending from the upper surface to the lower surface, and an area of the upper surface is smaller than an area of the lower surface;
• an adhesive layer disposed under the light blocking pattern layer, wherein the upper surface of each of the plurality of light absorption patterns in the light blocking pattern layer is spaced apart from the first base film and the lower surface of each of the plurality of light absorption patterns in the light blocking pattern layer is contacted to the adhesive layer;
• a second base film attached to the light blocking pattern layer by the adhesive layer;
• and
• a prism structure disposed under the second base film and including a plurality of prisms, wherein a vertex of each of the plurality of prisms is facing opposite to the viewing direction and an edge of each of the plurality of prisms is extended in a third direction forming an angle in a range of 80° to 100° with respect to the first direction and the second direction.