OPTICAL FILM, POLARIZING PLATE, AND LIQUID CRYSTAL DISPLAY DEVICE

摘要

An optical film has a film a formed of a cyclic olefin resin, and a homeotropically orientated optical anisotropic layer b disposed on the film a. This optical film preferably satisfies the below listed formulae (1) to (3).
(1) -600 nm‰¦ Rth‰¦ 200 nm
(2) 0 nm‰¦ R‰¦ 600 nm
(3) NZ‰¦ 1
(In formulae (1) to (3), Rth indicates the retardation in the thickness direction of the optical film at a wavelength of 550 nm; R indicates the in-plane retardation of the optical film at a wavelength of 550 nm; and NZ indicates (nx - nz)/(nx-ny)).
When the optical film is used in an ISP mode liquid crystal display device, light leakage and color fading (discoloration) during black display are prevented stably for a long term, and a good viewing angle compensation effect is obtained (i.e., high contrast ratio at all angles).