Optical film and manufacturing process thereof

A process for manufacturing an optical film having a light-incident portion and a light exit portion, comprising:

• preparing a first mold engraved with a shape of the light-incident portion and a second mold engraved with shapes of lens structures of the light exit portion;
• etching shapes of protrusions in the second mold by using a laser beam, the first mold engraved with a shape of a light-incident portion and the second mold engraved with shapes of lens structures of the light exit portion;
• and
• injecting a curable resin between the first mold and the second mold and curing the curable resin,
• wherein the shapes of the protrusions are formed on crest regions of the lens structures of the second mold and satisfy the requirements of the following expressions:
• 80×H1/3≦P≦200×H1/3 and 0.1×D≦H≦D, provided that a mean diameter of the protrusions is represented by ‘D’, a mean height of the protrusions is represented by ‘H’, and a mean distance between adjacent protrusions is represented by ‘P’, and
• the etching of the shapes of the protrusions is performed while changing an initial phase of the laser beam along a transverse direction of the optical film such that the shapes of the protrusions are arranged to have uniform intervals therebetween along a lengthwise direction of the optical film and to have different initial positions thereof along the transverse direction of the optical film.