| 摘要 |
PROBLEM TO BE SOLVED: To provide a wide band λ/4 plate easy to manufacture by providing a long transparent support and an optical anisotropic layer containing a liquid crystal compound, setting the phase difference of the optical anisotropic layer to π, and setting the angle formed by the in-plane delayed phase axis of the optical anisotropic layer and the length direction of the transparent support substantially to a specified angle. SOLUTION: This phase difference plate is formed of a long transparent support and an optical anisotropic layer. The phase difference of the optical anisotropic layer is π. Namely, in the measurement of retardation value of the optical anisotropic layer, the retardation value for the wavelength 550 nm is 269 nm as shown in the graph, and the phase difference (λ/2) of π is substantially shown for the wavelength 550 nm. The angle formed by the length direction of the transparent support and the in-plane delayed phase axis of the optical anisotropic layer is 75 deg.. The optical anisotropic layer contains a discotic liquid crystal molecule, and the discotic liquid crystal molecule is vertically aligned. The direction of the disc surface of the discotic liquid crystal molecule corresponds to the in-plane delayed phase axis of the optical anisotropic layer. |
