| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a retardation plate which contributes improvement of display characteristics and is especially suitable as a λ/4 plate, capable of improving tint of color from an oblique direction, and to provide a polarizing plate, a luminance improving film, and to provide a liquid crystal display that uses the retardation plate as the λ/4 plate. <P>SOLUTION: The retardation plate has an optical anisotropic layer in which a liquid crystalline compound is fixed, wherein Nz presented by Relation (1) is less than -0.3 in the wavelength region of 450 nm to 650 nm and a relation among in-plane retardation values at wavelengths 450 nm, 550 nm and 650 nm is presented by Relation (2): where Nz=0.5+Rth/Re, Relation (1) and Re(450)<Re(550)<Re(650), Relation (2). Here, an embodiment such that the relation among retardation values in the thickness direction at respective wavelengths is presented by Relation (3) is preferable: Rth(450)>Rth(550)>Rth(650), Relation (3). Furthermore, the polarizing plate, the luminance-improving film and the liquid crystal display that uses the retardation plate are also provided. <P>COPYRIGHT: (C)2008,JPO&INPIT |
