Patent ID: 8384847

Claim:
A prism sheet, comprising: a base film made of a transparent material, the base film having a flat first surface; and a light refracting part including a plurality of unit prisms unitarily formed with the base film at a second surface of the base film, opposite to the flat first surface, the unit prisms having a predetermined shape of a cross section and being oriented in a same direction, wherein: each of the unit prisms has a ridge that has an inclination changing point at which a first inclined portion of the ridge meets a second inclined portion of the ridge, the first inclined portion of the ridge is inclined at a first angle that is greater than 0° and less than 90° relative to a line perpendicular to the flat first surface, and the second inclined portion of the ridge is inclined at a second angle that is greater than 0° and less than 90° relative a line perpendicular to the flat first surface, and the first angle is not equal to the second angle.