Liquid crystal display having improved wavelength dispersion characteristics

摘要

A multilayer optical retardation compensation film having at least one positive C-plate and at least one negative C-plate is used in an LCD device. The multilayer film may have a substantially flat wavelength dispersion curve, or the multilayer film combined with other layers in the LCD device may have a substantially flat wavelength dispersion curve. Polymer films for the positive C-plate may be identified according to their absorbance maxima at certain wavelength ranges.

主权项

1. An optical retardation compensation film having a proper wavelength dispersion curve wherein R450/R550 is 1.20 to 2.00, R550/R650 is 1.10 to 1.60, and R650/R750 is 1.00 to 1.40, wherein R450, R550, R650 and R750 are the retardation values in the thickness direction of the optical compensation film at the wavelengths 450 nm, 550 nm, 650 nm, and 750 nm, respectively; wherein the optical film has a positive birefringence value throughout the wavelength range of 400 nm<λ<800 nm, wherein the film is cast from a solution comprising a polymer composition having a polymer segment with a polymer backbone, a light stable optically anisotropic sub-unit (OASU) attached directly to the polymer backbone via at least one covalent bond, wherein the OASU is capable of orienting perpendicular to the polymer backbone, and the higher the perpendicularity of the OASU, the larger the value of the positive birefringence of the polymer film.