Liquid crystal display device

A liquid crystal display device comprising:

• a liquid crystal display panel comprising a first substrate having a plurality of reflection patterns protruding from a major surface of the first substrate, a second substrate disposed to be opposed to the first substrate, and a liquid crystal layer including liquid crystal molecules, which are twist-aligned at a twist angle of 70°±10°, held between the first substrate and the second substrate;
• and
• an optical element provided on an outer surface of the second substrate,
• wherein the optical element includes a polarizer plate, a first retardation plate which is disposed between the polarizer plate and the liquid crystal display panel and imparts a phase difference of a ½ wavelength between light rays of a predetermined wavelength, which pass through a fast axis and a slow axis of the first retardation plate, and a second retardation plate which is disposed between the first retardation plate and the liquid crystal display panel and imparts a phase difference of a ¼ A wavelength between light rays of a predetermined wavelength, which pass through a fast axis and a slow axis of the second retardation plate,
• a retardation value Δn·d of the liquid crystal layer is set at 200 nm ±30 nm, where Δn is a refractive index anisotropy of the liquid crystal layer and d is a thickness of the liquid crystal layer, and
• wherein a horizontal direction of the major surface of either of the first and second substrates is a reference azimuth, a director of the liquid crystal molecules is set at 270° relative to the reference azimuth, an absorption axis of the polarizer plate is set at 15°±0.5° relative to the reference azimuth, and a slow axis of the second retardation plate is set at 90°±0.5° relative to the reference azimuth.

A liquid crystal display device comprising:

• a liquid crystal display panel comprising a first substrate having a plurality of reflection patterns protruding from a major surface of the first substrate, a second substrate disposed to be opposed to the first substrate, and a liquid crystal layer including liquid crystal molecules, which are twist-aligned at a twist angle of 70°±10°, held between the first substrate and the second substrate;
• and
• an optical element provided on an outer surface of the second substrate,
• wherein the optical element includes a polarizer plate, a first retardation plate which is disposed between the polarizer plate and the liquid crystal display panel and imparts a phase difference of a ½ wavelength between light rays of a predetermined wavelength, which pass through a fast axis and a slow axis of the first retardation plate, and a second retardation plate which is disposed between the first retardation plate and the liquid crystal display panel and imparts a phase difference of a ¼ A wavelength between light rays of a predetermined wavelength, which pass through a fast axis and a slow axis of the second retardation plate,
• a retardation value Δn·d of the liquid crystal layer is set at 200 nm 30 nm, where Δn is a refractive index an isotropy of the liquid crystal layer and d is a thickness of the liquid crystal layer, and
• with respect to at least one of the first retardation plate and the second retardation plate, an Nz coefficient, which is defined by (nx−nz)/(nx−ny), is set in a range of less than 1, where nx and ny are refractive indices in mutually perpendicular directions in a plane of said at least one of the first retardation plate and the second retardation plate, and nz is a refractive index in a normal direction to the plane.