Abstract: A method of generating a Computer Generated Hologram (CGH) using the diffraction specific algorithm allows a curved wavefront to be produced from a single hogel, rather than the planar waves of the prior art. This allows a wavefront from a single hogel to generate a point in the image volume. An imaginary wavefront is transmitted from each point in the image volume and sampled at a plurality of points over the hogel. These samples are used to produce a set of complex Fourier coefficients that can be used to approximate the original waveform.

Abstract: A system includes a computer generated hologram (CGH) design plane and a processor capable of representing a three dimensional object. The processor is configured to represent a surface of the three dimensional object by a facet, impose a grid defining a set of nodes upon the facet, and associate object points with each node of the grid. The processor is further configured to orient the facet to include a common global origin in the CGH design plane and displace the object points away from their associated node in a random or pseudo random direction parallel to the CGH design plane.

Abstract: The invention provides an improved means for displaying computer generated hologram (CGH). Images appearing in the image volume are realised as a set of planar facets that approximate to the shape of the original object to be displayed. These facets are populated with points, that act as the visible parts of the displayed image. When an object is displayed, certain facets will not be face on the viewing zone. This will result in an apparent surplus of points on these facets, which is wasteful of computing effort. The current invention thus provides for certain facets to be denuded of points if these facets are not presented face on to the viewing zone of the CGH. The invention is mainly applicable for producing CGHs using the interference based algorithm, but can also be used in other types of 3D display that make up objects from an array of points.

Abstract: A method of displaying a computer generated hologram includes displaying the image as a set of facets that approximated to the true shape of the object to be displayed. Each of these facets is populated with points that together make up the image. The invention provides a number of array structures that allow adjoining facets at different orientations and angles to be populated with point without creating areas around the join of either point overpopulation or point underpopulation, and so results in a higher quality image. The invention is mainly applicable for producing interference base Computer Generated Holograms, but can also be used in other types of 3D display that make up objects from an array of points.

Abstract: A method of generating a Computer Generated Hologram (CGH) using the diffraction specific algorithm allows a curved wavefront to be produced from a single hogel, rather than the planar waves of the prior art. This allows a wavefront from a singel hogel to generate a point in the image volume. An imaginary wavefront is transmitted from each point in the image volume and sampled at a plurality of points over the hogel. These samples are used to produce a set of complex Fourier coefficients that can be used to approximate the original waveform.

Abstract: An improved methof of producing an interference based computer generated hologram (CGH), where the angle dependent and angle independent components of light emanating from point sources of light on a virtual 3D object are calculated separately. This allows the angle independent components to be calculated only once per point source of light, but enables the angle dependent components to be calculated on a each point source of light to each CGH pixel basis. This method reduces the number of calculations required to produce a CGH, thus reducing computational load, but fully retains the image quality of the 3D image.

Abstract: An improved method of producing an interference based computer generated hologram (CGH), where pixels in the CGH design plane and/or object points on the virtual 3D object are grouped together. Occlusion and rendering properties are then calculated for one pixel or one object point of each group, but are used in calculations relating to all pixels or object points of that group. The pixel and object point grouping is used only for occlusion and rendering calculations and phase properties are still determined on a pixel by pixel basis. This method reduces the number of calculations required to produce a CGH, but retains the resolution related to the shape of the 3D image.

Abstract: A method of generating a Computer Generated Hologram (CGH) using the diffraction specific algorithm allows a curved wavefront to be produced from a single hogel, rather than the planar waves of the prior art. This allows a wavefront from a singel hogel to generate a point in the image volume. An imaginary wavefron is transmitted from each point in the image volume and sampled at a plurality of points over the hogel. These samples are used to produce a set of complex Fourier coefficients that can be used to approximate the original waveform.

Abstract: A method of displaying a computer generated hologram includes displaying the image as a set of facets that approximated to the true shape of the object to be displayed. Each of these facets is populated with points that together make up the image. The invention provides a number of array structures that allow adjoining facets at different orientations and angles to be populated with point without creating areas around the join of either point overpopulation or point underpopulation, and so results in a higher quality image. The invention is mainly applicable for producing interference base Computer Generated Holograms, but can also be used in other types of 3D display that make up objects from an array of points.

Abstract: A procedure for displaying Diffraction Specific (DS) Computer Generated Holograms (CGH) includes the provision of a novel diffraction table (DT) modified so as to store a complete decoded fringe for each point capable of being projected into the image volume. When generating a DS CGH the diffraction table is produced that holds data relating to the image to be projected. The prior art stores in this diffraction table a set of hogel vectors that are used to select a set of basis fringes relating to each point to be displayed on the CGH. This means that each basis fringe corresponding to a particular hogel vector must be accumulated together with all the others before a complete fringe is produced. The pre-computation of the fringes as per the current invention singificantly reduces the online processing requirements of producing an image, as the new DT can be produced offline with no knowledge of the image to be displayed.