A method for digitally generating a hologram plane from a three-dimensional scene, cut into a plurality of planes parallel to the hologram plane. The method includes for a current plane: counting a number of points of the non-zero amplitude scene; choosing a first or second technique for propagating a light wave emitted by the current plane as a function of a number of points of non-zero amplitude included in the current plane and with a preset threshold value, the first, point-based technique calculating the propagation of a sum of light waves emitted by point sources constituted by the points of the scene portion of a non-zero amplitude of the current plane on a following plane, and the second, field-based technique, globally calculating a light wave emitted by the scene portion situated in the current plane on a given plane; and processing the current plane according to the chosen propagation technique.

A hologram generating apparatus is provided. The apparatus includes a hologram signal generating unit configured to, based on light projected on at least some points corresponding to an object, generate a hologram signal corresponding to the at least some points on at least one two-dimensional plane, a processor configured to calculate a sparsity corresponding to the two-dimensional plane based on the hologram signal, and to calculate a fringe pattern based on at least some of the hologram signal, and a pattern writing unit configured to record the fringe pattern on a computer-generated holography (CGH) plane, wherein the processor is further configured to repeatedly calculate a fringe pattern until a number of dominant signals of the calculated fringe pattern coincides with a predetermined threshold value determined based on the sparsity.

Disclosed is a hologram image generating system, which includes a preprocessor that receives point cloud data to convert the received point cloud data into depth map image data, a depth map hologram processor that generates depth map hologram data based on the depth map image data, and a hologram generating device that generates a hologram image based on the depth map hologram data.

A holographic display device for computing a video hologram of a scene is disclosed. The scene comprises a multitude of object points. The holographic display device comprises at least one light modulator means. Said holographic display device is configured to perform the steps of (a) defining a visibility region within a periodicity interval of the video hologram of the scene to be reconstructed; (b) for each object point, defining a modulator region by the defined visibility region together with each object point of the scene to be reconstructed, where a sub-hologram of an object point of the scene to be reconstructed is computed for each modulator region, and where an entire video hologram is created by superposition of said sub-holograms; (c) determining complex hologram values of a sub-hologram in a modulator region from a wave front of an object point to be reconstructed by computing modulation functions of an imaging element which is modeled in the respective modulator region of said holographic display device, and in whose focal point the object point to be reconstructed lies, where the sub-hologram of said object point is computed using the modulation functions, and (d) encoding the video hologram of the scene into the screen means.

A system for generating multi-depth image sequence comprising a modulation array. The modulation array comprising a plurality of light modulators which may shift light incident upon the modulators by a number of degrees. The plurality of light modulators may shift light in concert according to a modulation shift pattern. The modulation shift pattern can be configured to focus incident light to a voxel or to form a 3-D image. One or more modulation shift patterns can be changed or cycled through to raster one or more image objects in one or more image depth planes.

A holographic display device for computing a video hologram of a scene is disclosed. The scene comprises a multitude of object points. The holographic display device comprises at least one light modulator means. Said holographic display device is configured to perform the steps of (a) defining a visibility region within a periodicity interval of the video hologram of the scene to be reconstructed; (b) for each object point, defining a modulator region by the defined visibility region together with each object point of the scene to be reconstructed, where a sub-hologram of an object point of the scene to be reconstructed is computed for each modulator region, and where an entire video hologram is created by superposition of said sub-holograms; (c) determining complex hologram values of a sub-hologram in a modulator region from a wave front of an object point to be reconstructed by computing modulation functions of an imaging element which is modeled in the respective modulator region of said holographic display device, and in whose focal point the object point to be reconstructed lies, where the sub-hologram of said object point is computed using the modulation functions, and (d) encoding the video hologram of the scene into the screen means.

An apparatus for generating a hologram in accordance with an embodiment of the present invention includes: a frequency component data generating part configured for generating frequency component data comprising a spatial frequency component of a spherical wave generated at a sampling point of a graphic model; an input part configured for receiving a generation angle and a generation position corresponding to a plane hologram; a frequency component search part configured for extracting a hologram target component for a main spatial frequency vector having a most similar direction with the generation angle from the frequency component data; an angular spectrum generating part configured for generating an angular spectrum by multiplying a predetermined factor to the hologram target component and propagating the angular spectrum according to the generation position; and a hologram generating part configured for generating the plane hologram by applying inverse Fourier transform to the angular spectrum.

Provided is an apparatus and method for generating a hologram pattern with a reduced amount of computation. The apparatus may include a reference depth layer setting unit configured or having a capacity to set a reference depth layer using data associated with a three-dimensional (3D) object, a first hologram pattern generating unit configured to generate a first hologram pattern corresponding to the 3D object in the reference depth layer, and a second hologram pattern generating unit configured to generate a second hologram pattern in a hologram plane using the first hologram pattern.

A technique for fabricating a highlight hologram based on a digital object performs point sampling on the object and represents each sampled point as a geometric patch. A set of geometric patches corresponding to sampled points from the object are fabricated into a substrate. A paraboloid patch may be used for reflective substrates while a hyperboloid may be used for transmissive substrates. To avoid specifying overlapping patches, which are impractical to fabricate, certain of the sample points may be merged. An output set of grooves is saved and may be used to specify fabrication of a highlight hologram on the physical substrate.

An analytical method for computing a video hologram for a holographic reproduction device having at least one light modulation means is disclosed, wherein a scene split into object points is encoded as a whole hologram and can be seen as a reconstruction from a visibility region, located within a periodicity interval of the reconstruction. The visibility region, together with each object point of the scene to be reconstructed, defines a sub-hologram and the whole hologram is generated from a superposition of sub-holograms, wherein the complex hologram values of a sub-hologram are determined from the wave front of the respective object point to be reconstructed in a modulator region of the light modulation means, by calculating and evaluating the transmission or modulation functions of an imaging element formed in the modulator region. The object point to be reconstructed is located in the focal point of the imaging element.