Optical film and display device including the same

An optical film comprising:

• a first pattern layer comprising a base part and a plurality of protruding parts disposed on the base part, wherein the first pattern layer has a first refractive index;
• and
• a second pattern layer disposed on the first pattern layer, wherein the second pattern layer has a second refractive index greater than the first refractive index,
• wherein each of the protruding parts comprises:
• a bottom surface adjacent to the base part;
• an upper surface opposite to the bottom surface and parallel to the bottom surface;
• and
• a side surface disposed between the bottom surface and the upper surface,
• wherein the side surface comprises n sub-inclined surfaces, inclination angles of which are different from each other, or comprises a curved surface which is convex in a direction of the second pattern layer,
• each of the inclination angles of the n sub-inclined surfaces is an acute angle thereof with respect to the bottom surface, and
• n is an integer of 3 or greater 1,
• wherein
• the side surface comprises the n sub-inclined surfaces having different inclination angles from each other,
• each of the protruding parts comprises n sub-protruding parts, and
• on a cross-section vertical to the base part, each of the n sub-protruding parts has a trapezoidal shape.

An optical film comprising:

• a first pattern layer comprising a base part and a plurality of protruding parts disposed on the base part, wherein the first pattern layer has a first refractive index;
• and
• a second pattern layer disposed on the first pattern layer, wherein the second pattern layer has a second refractive index greater than the first refractive index,
• wherein each of the protruding parts comprises:
• a bottom surface adjacent to the base part;
• an upper surface disposed opposite to the bottom surface and parallel to the bottom surface;
• and
• a side surface disposed between the bottom surface and the upper surface,
• wherein the side surface comprises n sub-inclined surfaces, inclination angles of which are different from each other, or is a curved surface which is convex in a direction of the second pattern layer,
• each of the inclination angles of the n sub-inclined surfaces is an acute angle thereof with respect to the bottom surface,
• n is an integer of 3 or greater, and,
• on a cross-section vertical to the base part, a ratio of a width of the upper surface to a width of the bottom surface is in a range of about 0.35 to about 0.5,
• wherein
• each of the protruding parts comprises n sub-protruding parts,
• a width of a sub-bottom surface of an m-th sub-protruding part is identical to a width of a sub-upper surface of an (m−1)-th sub-protruding part, and
• m is an integer greater than or equal to 2 and less than or equal to n.

A display device comprising:

• a liquid crystal display panel;
• and
• an optical film disposed on an upper surface of the liquid crystal display panel,
• wherein the optical film comprises:
• a first pattern layer comprising a base part and a plurality of protruding parts disposed on the base part, wherein the first pattern layer has a first refractive index;
• and
• a second pattern layer disposed on the first pattern layer, where the second pattern layer has a second refractive index greater than the first refractive index,
• wherein each of the protruding parts comprises:
• a bottom surface adjacent to the base part;
• an upper surface opposite to the bottom surface and parallel to the bottom surface;
• and
• a side surface disposed between the bottom surface and the upper surface,
• wherein the side surface comprises n sub-inclined surfaces, inclination angles of which are different from each other, or comprises a curved surface which is convex in a direction of the second pattern layer,
• each of the inclination angles of the n sub-inclined surfaces is an acute angle thereof with respect to the bottom surface, and
• n is an integer of 3 or greater,
• wherein
• each of the protruding parts comprises n sub-protruding parts,
• a width of a sub-bottom surface of an m-th sub-protruding part is identical to a width of a sub-upper surface of an (m−1)-th sub-protruding part, and
• m is an integer greater than or equal to 2 and less than or equal to n.