| 摘要 |
PROBLEM TO BE SOLVED: To provide a phase difference plate with high-performance in a wide band, which can be formed at a low cost from single material without needing laminating formation. SOLUTION: The phase difference plate is formed by using a composition containing a copolymer satisfying Δn (450)<Δn (550)<Δn (650), when the specific double refractivity value (Δn) in wavelength of 450 nm, wavelength of 550 nm and wavelength of 650 nm is defined as the Δn (450), the Δn (550) and the >=n(650), respectively, and has a chain showing the positive uniaxiality and a chain showing the negative uniaxiality, when a uniaxial orientation rule is given. It is preferable that the chain showing the positive uniaxiality is a norbornene chain, and the chain showing the negative uniaxiality is at least one kind selected from a styrene chain, a styrene/maleic anhydride copolymer chain, a styrene/acrylonitrile copolymer chain, a styrene/methyl metacrylate copolymer chain or the like. |
