Twisted nematic liquid crystal display with compensation film

摘要

An optical compensation film for Ordinary-mode Normally White Twisted Nematic Liquid Crystal Display comprising, a first and a second optically anisotropic layers containing positively birefringent material disposed on a substrate, wherein the optic axis of said first optically anisotropic layer tilts in a first plane with an average tilt angle between 10° and 60°, and the optic axis of said second optically anisotropic layer tilts in a second plane with an average tilt angle between 0° and 30°, and said average tilt angle of said first optically anisotropic layer and said average tilt angle of said second optically anisotropic layer are different, and said first and said second planes are perpendicular to the plane of said optical compensation film with the angle between said first and said second planes being s 90±10°, and the retardation defined by (ne1-no1)d1 of said first optically anisotropic layer is between 60 nm and 220 nm and the retardation defined by (ne2-no2)d2 of the said second optically anisotropic layers is between 85 nm and 210 nm, where ne1 and no1 are extraordinary and ordinary indices of refraction of said positively birefringent material of said first optically anisotropic layer, respectively, and ne2 and no2 are extraordinary and ordinary indices of refraction of said positively birefringent material of said second optically anisotropic layer, respectively, and d1 and d2 are thickness of the said first and said second optically anisotropic layer, respectively.