Patent ID: 9618682
Date: 2017-04-11
CPC Classifications: G02B,G02F

Claim:
1. An optical sheet comprising: a base film; a high refractive index layer having a plurality of prism portions on the base film; and a low refractive index layer positioned on the high refractive index layer, and covering the plurality of prism portions and having a surface parallel to the base film, each of the prism portions including an incidence surface on which incident light is refracted and a reflective surface on which the refracted light is reflected, the incidence surface including a bent for refracting the incident light towards the reflective surface, wherein the low refractive index layer includes a bottom surface having a refractive index difference at an interface between an air layer and the low refractive index layer, and wherein a portion of the low refractive index layer is disposed between the plurality of prism portions and the bottom surface, and the plurality of prism portions do not contact the bottom surface, wherein the plurality of prism portions continuously extend in one direction away from the base film and each of the plurality of prism portions includes an incidence surface configured to receive incident light and a refractive plane where the incident light passing through the incidence surface is reflected, and wherein an angle between the incidence surface of each the plurality of prism portions and a surface of the base film is equal to 90 degrees.