A light field display device includes: a display module; an optical coupler emitting a third image obtained by combining a first image and a second image, and including a first surface, a second surface and an emission surface emitting the third image, wherein the first image is emitted from the display module and is incident on the first surface, wherein the second image is incident on the second surface; and a controller configured to generate image data based on 3D modeling data and provide the image data to the display module. The optical coupler includes: an optical waveguide including the first, second and emission surfaces, and a third surface; a beam splitter in the optical waveguide; and a concave mirror adjacent to the third surface of the optical waveguide, and wherein the controller moves the concave mirror in correspondence with depth information included in the 3D modeling data.