Prism Sheet, a Back-Light Unit Using Said Prism Sheet, and a Transmission Type Liquid Crystal Display Device

摘要

[Objective] Providing a prism sheet, a back-light unit using the prism sheet, and a transmission type liquid crystal display device. [Means to Solve Problems] The prism sheet according to the present invention is the prism sheet 10 for changing a direction of light propagation by reflecting light L launched with an intensity distribution of a predetermined angle range wherein: a reflective surface for perfect reflection of light L comprises a higher order surface 18 constructed by at least a small curvature surface and a surface different from the small curvature surface. Further, the present invention provides the back-light unit comprising the above-described prism sheet and the transmission type liquid crystal display device.