A display device comprising: a display panel having a display surface, and an optical film comprising: a first refractive layer having an upper surface and a lower surface including first projections and second projections extending away from the upper surface in a first direction, the second projections having different heights than the first projections, and a second refractive layer disposed directly on the upper surface of the first refractive layer, the second refractive layer having a refractive index different from that of the first refractive layer wherein the first projections and the second projections form a first lens pattern and a second lens pattern, respectively, each of which extends in a second direction different from the first direction, the first lens pattern and the second lens pattern are alternately arranged in a third direction different from the first direction and the second direction, characterized in that the first projections have lateral sides with different angles of inclination (a11, a12) that decrease in the first direction away from the upper surface; the first projections and the second projections further form a third lens pattern and a fourth lens pattern, respectively, each of which extends in the third direction, and the third lens pattern and the fourth lens pattern are alternately arranged in the second direction. a display panel having a display surface, and an optical film comprising: a first refractive layer having an upper surface and a lower surface including first projections and second projections extending away from the upper surface in a first direction, the second projections having different heights than the first projections, and a second refractive layer disposed directly on the upper surface of the first refractive layer, the second refractive layer having a refractive index different from that of the first refractive layer wherein the first projections and the second projections form a first lens pattern and a second lens pattern, respectively, each of which extends in a second direction different from the first direction, the first lens pattern and the second lens pattern are alternately arranged in a third direction different from the first direction and the second direction, characterized in that the first projections have lateral sides with different angles of inclination (a11, a12) that decrease in the first direction away from the upper surface; the first projections and the second projections further form a third lens pattern and a fourth lens pattern, respectively, each of which extends in the third direction, and the third lens pattern and the fourth lens pattern are alternately arranged in the second direction. a first refractive layer having an upper surface and a lower surface including first projections and second projections extending away from the upper surface in a first direction, the second projections having different heights than the first projections, and a second refractive layer disposed directly on the upper surface of the first refractive layer, the second refractive layer having a refractive index different from that of the first refractive layer wherein the first projections and the second projections form a first lens pattern and a second lens pattern, respectively, each of which extends in a second direction different from the first direction, the first lens pattern and the second lens pattern are alternately arranged in a third direction different from the first direction and the second direction, characterized in that the first projections have lateral sides with different angles of inclination (a11, a12) that decrease in the first direction away from the upper surface; the first projections and the second projections further form a third lens pattern and a fourth lens pattern, respectively, each of which extends in the third direction, and the third lens pattern and the fourth lens pattern are alternately arranged in the second direction.