Directional light guide plate, directional surface light source, and three-dimensional image display apparatus employing the directional surface light source

摘要

Directional light guide plates, directional surface light sources, and three-dimensional (3D) image display apparatuses employing the directional surface light sources are provided. Each of the directional light guide plates includes a plurality of viewing zone separation units having a refractive index different from that of a light guide unit, for separating light into left and right viewing zones.

主权项

1. A directional light guide plate for a two-dimensional (2D)/three-dimensional (3D) switchable directional surface light source, the directional light guide plate comprising:
a light guide unit comprising first and second incident surfaces respectively formed on first and second side surfaces on substantially opposing sides of the light guide unit, configured to guide light incident on the first and second incident surfaces via total internal reflection inside the light guide unit; and viewing zone separation units formed of a substantially transparent material having a refractive index greater than that of the light guide unit, each of the viewing zone separation units being aligned in parallel with each other and disposed in a flat third surface of the light guide unit, wherein each of the viewing zone separation units comprises:
a first interface contacting the light guide unit and extending in a lengthwise direction with respect to the first incident surface;a second interface contacting the light guide unit and extending in a lengthwise direction with respect to the second incident surface; andan exit surface, and wherein the first and second interfaces are formed so that light incident on the first incident surface and light incident on the second incident surface are separated into different viewing zones, wherein the directional light guide plate and a light source unit form the two-dimensional (2D)/three-dimensional (3D) switchable directional surface light source, and wherein each of the viewing zone separation units is formed in a shape in which a first inclination angle between the first interface and the exit surface differs according to a distance from the first incident surface and a distance from the second incident surface, and a second inclination angle between the second interface and the exit surface differs according to the distance from the first incident surface and the distance from the second incident surface.