Patent ID: 8134781

Claim:
An optical film having a light-incident portion and a light exit portion, comprising: a plurality of lens structures formed on the light exit portion so as to collect or diffuse light; and a plurality of protrusions formed on crest regions of the plurality of lens structures, wherein the plurality of the protrusions satisfy the requirements of the following expressions: 80×H 1/3 ≦P≦200×H 1/3 and 0.1×D≦H≦D, provided that a mean diameter of protrusions is represented by ‘D’, a mean height of protrusions is represented by ‘H’, and a mean distance between adjacent protrusions is represented by ‘P’, and the plurality of protrusions are arranged to have uniform intervals therebetween along a lengthwise direction of the optical film and to have different initial positions thereof along a transverse direction of the optical film.