Liquid crystal display including an anisotropic scattering layer
View Patent ↗A liquid crystal display comprises a top polarizer 11, an optical compensating element, an anisotropic scattering layer 10, a scattering layer 7, and a liquid crystal device 20 incorporating therein a reflective layer 9. When the direction of viewing direction of the anisotropic scattering layer is designated as the Y-axis direction, and a direction oriented substantially at right angles to the Y-axis direction is designated as the X-axis direction, light entering the anisotropic scattering layer is scattered over a wider angle along the Y-axis direction than along the X-axis direction. Further, the incident angle dependence of the straight-go transmittance of the anisotropic scattering layer is symmetrical about the layer normal, and the straight-go transmittance in the layer normal direction is lower than the straight-go transmittance in any oblique direction.
1. A liquid crystal display comprising a first substrate having a reflective layer and a first electrode, a second substrate having a second electrode, and a nematic liquid crystal material with twisted orientation sandwiched between the first and second substrates, wherein
the liquid crystal display includes an anisotropic scattering layer which is provided nearer to a viewing side than to the reflective layer, and whose straight-go transmittance varies depending on the incident angle, and
when the viewing direction of the anisotropic scattering layer is designated as the Y-axis direction, and a direction orientated substantially at right angles to the Y-axis direction is designated as the X-axis direction, the anisotropic scattering light is provided with a part in which light entering the anisotropic scattering layer is scattered over a wider angle along the Y-axis direction than along the X-axis direction, and
wherein the straight-go transmittance of the anisotropic scattering layer has an incident angle dependence that is symmetrical about a layer normal to the anisotropic scattering layer for both the X-axis direction and the Y-axis direction, the straight-go transmittance of the anisotropic scattering layer in the direction of the layer normal is lower than the straight-go transmittance thereof in any oblique direction, and maximum straight-go transmittance is substantially the same in value for both the X-axis direction and the Y-axis direction.
2. A liquid crystal display comprising a first substrate having a reflective layer and a first electrode, a second substrate having a second electrode, and a nematic liquid crystal material with twisted orientation sandwiched between the first and second substrates, wherein
the liquid crystal display includes an anisotropic scattering layer which is provided nearer to a viewing side than to the reflective layer, and whose straight-go transmittance varies depending on the incident angle, and
when the viewing direction of the anisotropic scattering layer is designated as the Y-axis direction, and a direction orientated substantially at right angles to the Y-axis direction is designated as the X-axis direction, the anisotropic scattering light is provided with a part in which light entering the anisotropic scattering layer is scattered over a wider angle along the Y-axis direction than along the X-axis direction, and
wherein the straight-go transmittance of the anisotropic scattering layer has an incident angle dependence that is asymmetrical along the X-axis direction about a layer normal to the anisotropic scattering layer, and symmetrical along the Y-axis direction, and the straight-go transmittance of the anisotropic scattering layer in the direction of the layer normal is lower than the straight-go transmittance thereof in any oblique direction.
3. A liquid crystal display as claimed in claim 2 , wherein the straight-go transmittance of the anisotropic scattering layer in oblique directions has a characteristic such that the maximum straight-go transmittance is higher for light rays obliquely incident along the X-axis direction than for light rays obliquely incident along the Y-axis direction.
4. A liquid crystal display as claimed in claim 1 or 2 , wherein a scattering layer is provided in addition to the anisotropic scattering layer.
5. A liquid crystal display as claimed in claim 1 or 2 , wherein the nematic liquid crystal material has a twist angle that lies within a range of 180° to 260°.
6. A liquid crystal display as claimed in claim 1 or 2 , wherein the reflective layer is formed as a transflective layer, and a backlight is provided on the outside of the first substrate.
7. A liquid crystal display as claimed in claim 1 or 2 , wherein a color filter consisting of a plurality of colors is provided on either one of the first and second substrates.
8. A liquid crystal display as claimed in claim 1 or 2 , wherein at least one optical compensating element is provided on the second substrate side, and the optical compensating element is constructed using a retardation film or a twisted retardation film or both.