Patent ID: 7961276

Claim:
A liquid crystal display device, comprising: a liquid crystal cell in which a liquid crystal layer is provided between a pair of substrates; and a circular polarizer provided to each substrate of the liquid crystal cell, each of said circular polarizers having a plurality of in-plane retardation plates having a retardation Re>0 in an in-plane direction when the retardation Re of an in-plane direction is (nx−ny)×d, and a retardation Rth in a thickness direction is ((nx+ny)/2−nz)×d (wherein nx is a refractive index in a direction in which a maximum refractive index occurs in a plane, ny is a refractive index in an in-plane direction orthogonal to the direction in which the maximum refractive index occurs, nz is a refractive index in a thickness direction, and d is a thickness), and a polarizer disposed on an opposite side of said liquid crystal layer from said in-plane retardation plates, wherein, in each of said circular polarizers, at least one of said in-plane retardation plates has a slow axis not perpendicular to an absorption axis of said polarizer, wherein a first pair of said in-plane retardation plates is formed by i) a first one of the plurality of said in-plane retardation plates in a first of said circular polarizers, and ii) a second one of the plurality of said in-plane retardation plates in a second of said circular polarizers, said first of said circular polarizers being disposed on a first side of the liquid crystal cell and said second of said circular polarizers being disposed on a second side of the liquid crystal cell opposite the first side of the liquid crystal cell, a first of said first pair of said in-plane retardation plates configured such that Rth>0, and a second of said first pair of said in-plane retardation plates configured such that Rth<0, wherein a second pair of said in-plane retardation plates is formed by i) a third one of the plurality of said in-plane retardation plates in the first of said circular polarizers, and ii) a fourth one of the plurality of said in-plane retardation plates in the second of said circular polarizers, a first of said second pair of said in-plane retardation plates configured such that Rth>0, and a second of said second pair of said in-plane retardation plates configured such that Rth<0, wherein said first pair of said in-plane retardation plates is closer to the liquid crystal cell than the second pair of said in-plane retardation plates, wherein said in-plane retardation plates in which Rth>0 and said in-plane retardation plates in which Rth<0 constitute a plurality of said pairs of in-plane retardation plates, and said in-plane retardation plates of each of said pairs of in-plane retardation plates are configured to compensate for each other, and wherein a sum of Rth of the in-plane retardation plates, that constitute said circular polarizers and are disposed in between said polarizers, is 0.