Patent ID: 8508691
Filing Date: 2013-08-13
Classification: G02B,G02F

Abstract:
1. An optical path unit comprising, in sequence from a light incident direction: a light deflecting means; a first polarizing plate; a liquid crystal cell having a liquid crystal layer provided between a pair of substrates; and a second polarizing plate, wherein the first polarizing plate and the second polarizing plate are disposed such that transmission axes thereof have a crossed Nicols relationship; the light deflecting means has two prism films provided on a light incident surface with a plurality of linear prisms having a polygonal and tapered cross section and an endmost vertex angle of 90° to 110° at predetermined intervals; the light incident surfaces of the two prism films have a center-line average roughness Ra of 0.3 μm or less and a ten-point average roughness Rz of 1 μm or less; and one of the prism films is disposed such that a ridge line direction of the linear prisms is substantially in parallel with the transmission axis of the first polarizing plate, and the other prism film is disposed such that a ridge line direction of the linear prisms is substantially in parallel with the transmission axis of the second polarizing plate.