Patent ID: 7967461

Claim:
A backlight module comprising: a light source producing light; a reflective plate that is positioned under the light source to reflect the light; and a prism plate including an incident surface and an emitting surface, the prism plate being positioned on the light source so that direct light from the light source and reflective light from the reflective plate are directly incident on the prism plate through the incident surface, wherein a light scattering unit scattering the direct light and the reflective light is positioned on the incident surface of the prism plate, and a prism pattern changing a traveling path of light incident through the incident surface is positioned on the emitting surface of the prism plate, wherein the light source is composed of line-shaped light sources, and the prism pattern extends in a longitudinal direction of the line-shaped light source and have a saw-toothed section or a trapezoid-shaped section, and wherein the line-shaped light sources are positioned to be spaced apart from each other at a distance of 20 mm to 40 mm, and the prism plate is positioned so that a distance between the reflective plate and the incident surface of the prism plate is 5 mm to 15 mm, and wherein a length of a base portion of the prism pattern in a width direction of the prism pattern is 10 μm to 500 μm, a height between the base portion and an apex of the prism pattern is 0.2 to 0.8 times the length of the base portion, an angle between the base portion and a side portion of the prism pattern is 35° to 45°, and a curvature of the apex is 20 μm to 200 μm.