Three-dimensional display device

A three-dimensional (3D) display device comprising:

• a display unit configured to display an image, the image comprising a first area, and a second area different from the first area;
• a display driver configured to display, on the display unit, a plurality of first images at the first area based on a depth component of the image and a second image at the second area based on a planar component of the image;
• a first lens array comprising a plurality of first lens elements provided at a first pitch on a rear side of the display unit;
• a second lens array comprising a plurality of second lens elements provided at a second pitch wider than the first pitch of the plurality of first lens elements on a rear side of the first lens array;
• a plurality of light source assemblies, each light source assembly of the plurality of light source assemblies being located on a rear side of a corresponding second lens element of the plurality of second lens elements and comprising a plurality of light sources;
• a light source driver configured to control the plurality of light source assemblies to illuminate the plurality of first images and the second image;
• and
• a diffusion sheet between the first lens array and the display unit and configured to diffuse incident light,
• wherein the plurality of light sources of each light source assembly are radially adjacent at a first distance from a principal point of the corresponding second lens element,
• wherein, based on the light source driver driving the plurality of light source assemblies, a number of light sources, among the plurality of light sources of each light source assembly, used to illuminate the second image is greater than a number of light sources used to illuminate one of the plurality of first images,
• wherein a position of the diffusion sheet is 0.9 times to 1.1 times a focal length of the first lens array from the first lens array, and
• wherein the first lens array further comprises ridges and the diffusion sheet is an anisotropic diffusion sheet configured to diffuse more incident light in a direction of the ridges of the first lens array than in a direction perpendicular to the direction of the ridges of the first lens array.