Directional backlight with a modulation layer

A method for generating a 3D image with a directional backlight having a modulation layer, comprising:

• specifying a plurality of characteristics for a plurality of directional pixels, each directional pixel comprising a patterned grating;
• fabricating a directional backplane comprising a slab of transparent material with the plurality of directional pixels arranged thereon, the transparent material slab being configured to guide a lightbeam;
• adding a modulation layer having a plurality of modulators above the directional backplane;
• illuminating the directional backplane with a plurality of input planar lightbeams, the input planar lightbeams being guided within the transparent material slab and being scattered out of the transparent material slab by the plurality of directional pixels into a plurality of directional lightbeams;
• and
• modulating the plurality of directional lightbeams with the plurality of modulators to generate multiple views of a 3D image.

A three-dimensional (3D) image-forming directional backlight, comprising:

• a directional backplane comprising a material layer configured to guide light as a planar lightbeam within the material layer, the directional backplane having a plurality of directional pixels configured to scatter out a portion of a plurality of input planar lightbeams guided within the material layer into a plurality of directional lightbeams directed away from a surface of the directional backplane as a light field, each directional pixel comprising a patterned grating, each directional lightbeam having a direction and an angular spread controlled by characteristics of a directional pixel in the plurality of directional pixels;
• and
• a modulation layer having a plurality of modulators configured to modulate the plurality of directional lightbeams, the modulation layer being adjacent to the surface of the directional backplane,
• wherein a set of modulated directional lightbeams from a corresponding set of the directional pixels represents a view of a plurality of different views that form a 3D image.