Patent ID: 9523808
Filing Date: 2016-12-20
CPC Classification: G02B

Claim Text:
1. A flat panel display device having a display panel and a back light unit, the back light unit comprising: a base film having a width and a length and including a high refractive film and a low refractive film on the high refractive film; a first incident pattern at a one side of a first surface of the base film; a reflective pattern on the first surface of the base film at an opposite side from the one side having the first incident pattern, wherein a distance between the first incident pattern and the reflective pattern is substantially equal to the length of the first surface of the base film, and wherein a length of the reflective pattern is substantially equal to the width of the first surface of the base film; a light radiating pattern on a second surface of the base film; and a light source spaced apart from the first incident pattern with a first focal length and providing an incident light to the first incident pattern.