Patent ID: 8915604

Claim:
A prism sheet, comprising: a base film having one flat surface; and an optical refractive section having a plurality of prisms arranged along a first direction to constitute first and second prism parts, the optical refractive section being integrally formed with another surface of the base film that is opposite to the flat surface of the base film, each of the prisms having a predetermined cross-sectional shape, wherein: the first prism part includes a first prism of the plurality of prisms, which first prism has a constant height along a second direction that intersects the first direction, and the second prism part includes a second prism of the plurality of prisms, which second prism has a variable height in the second direction, a maximum value of the variable height of the second prism being higher than the constant height of the first prism, wherein a line connecting highest heights of the second prism along the second direction is at a distance ranging from about 50% or less of the maximum value of the variable height of the second prism, from a center line of the second prism.