Liquid crystal display device
View Patent ↗A liquid crystal display device includes a first optical element which is provided on one of outer surfaces of a liquid crystal display panel including homogeneously aligned liquid crystal molecules and includes a first polarizer plate, a first retardation plate in which nematic liquid crystal molecules are solidified in a state in which the nematic liquid crystal molecules are hybrid-aligned in a liquid crystal state along a normal direction, and a second retardation plate, and a second optical element which is composed of a second polarizer plate.
1. A liquid crystal display device, comprising:
a liquid crystal display panel in which a liquid crystal layer including homogeneously aligned liquid crystal molecules is held between a first substrate and a second substrate which are disposed to be opposed to each other;
a first optical element which is provided on one of outer surfaces of the liquid crystal display panel and includes a first polarizer plate, and a first retardation plate and a second retardation plate which are disposed between the first polarizer plate and the liquid crystal display panel, and in the first optical element, an angle between an absorption axis of the first polarizer plate and a slow axis of the second retardation plate is set at about 45°, a slow axis of the first retardation plate and a director of the liquid crystal molecules included in the liquid crystal layer are set to be substantially parallel, and an angle between the slow axis of the first retardation plate and the slow axis of the second retardation plate is set at about 90°; and
a second optical element which includes a second polarizer plate provided on an other outer surface of the liquid crystal display panel, and in the second optical element, an angle between an absorption axis of the second polarizer plate and the absorption axis of the first polarizer plate is set at about 90°,
wherein the first retardation plate includes a liquid crystal film layer which imparts a predetermined retardation to light of a predetermined wavelength and in the first retardation plate nematic liquid crystal molecules are solidified in a state in which the nematic liquid crystal molecules are hybrid-aligned along a normal direction.
2. The liquid crystal display device according to claim 1 , wherein the first optical element controls a polarization state of light, which passes through the first optical element, in a manner that light having a polarization state of substantially linear polarization enters the liquid crystal layer.
3. The liquid crystal display device according to claim 1 , wherein the first retardation plate is composed of the liquid crystal film layer which is in contact with the second retardation plate and the one outer surface of the liquid crystal display panel.
4. The liquid crystal display device according to claim 1 , wherein a sum of a residual retardation of the liquid crystal layer and a frontal retardation of the first retardation plate is substantially equal to a frontal retardation of the second retardation plate.
5. The liquid crystal display device according to claim 1 , wherein the second optical element includes a third retardation plate between the second polarizer plate and the liquid crystal display panel, and
the third retardation plate has a refractive index anisotropy, which is defined by a relationship of nx =ny>nz, where nx and ny are refractive indices in mutually perpendicular directions in a plane of the third retardation plate, and nz is a refractive index in a normal direction of the third retardation plate.
6. The liquid crystal display device according to claim 1 , further comprising: a backlight unit which illuminates the liquid crystal display panel from the first optical element side.