1. Field of the Invention
The present disclosure is directed to an optical plate, a method of manufacturing the same and a liquid crystal display having the same, and more particularly, to an optical plate having improved light scattering power, a method of manufacturing the same and a liquid crystal display having the same.
2. Description of the Related Art
Since a liquid crystal display (LCD), which is widely used as a flat panel display, is a passive light-emitting device that is not self-luminescent, a backlight assembly is attached as a light source to a rear surface of an LCD panel, thereby implementing images. Thus, a quality of the LCD is influenced depending on a structure of the backlight assembly.
A backlight assembly is classified as an edge type or a direct type depending on the position of a light source with respect to a display surface. In the edge type backlight assembly, a lamp is positioned at a side of the display surface, so that a light guide plate for converting linear light into surface light is required. On the other hand, in the direct type backlight assembly, a lamp is positioned directly below the display surface, so that no light guide plate is required. Among these backlight assemblies, the direct type backlight assembly has high light efficiency, a simple structure, and a display surface of an unrestricted size, so that it is widely used for large-sized LCDs.
The direct type backlight assembly includes a plurality of lamps mounted under the display surface, a reflective plate for reflecting light emitted from the lamps to the display surface to prevent loss of light, and a diffusion plate and a diffusion sheet for diffusing light over the lamps to uniformly emit light.
However, since the direct type backlight assembly has lamps arranged on a plane, the shapes of the lamps, i.e., bright lines, appear on an LCD panel, and thus, a gap between the lamps and the LCD panel should be maintained to some degree. However, there is a thickness limitation, and a luminance nonuniformity is caused throughout the LCD panel. That is, since a plurality of lamps are positioned below the display surface in the direct type backlight assembly, the rear surface of the diffusion plate positioned perpendicular to the lamps has a different light intensity from the rear surface of the diffusion plate positioned between the lamps, which results in a luminance nonuniformity.