Abstract: A method of computing a hologram by determining the wavefronts at the approximate observer eye position that would be generated by a real version of an object to be reconstructed. In normal computer generated holograms, one determines the wavefronts needed to reconstruct an object; this is not done directly in the present invention. Instead, one determines the wavefronts at an observer window that would be generated by a real object located at the same position of the reconstructed object. One can then back-transforms these wavefronts to the hologram to determine how the hologram needs to be encoded to generate these wavefronts. A suitably encoded hologram can then generate a reconstruction of the three-dimensional scene that can be observed by placing one's eyes at the plane of the observer window and looking through the observer window.

Abstract: A method of computing a hologram for reconstructing an object using a display device. The display device enables a holographic reconstruction of the object. The display device includes a light source and an optical system to illuminate a hologram-bearing medium being encodable with the hologram. The method includes the steps of: (a) computing the hologram by determining the wavefronts at an approximate observer eye position that would be generated by a real version of the object to be reconstructed; and (b) encoding the computed hologram in the hologram-bearing medium.

Abstract: A method of computing a hologram by determining the wavefronts at the approximate observer eye position that would be generated by a real version of an object to be reconstructed. In normal computer generated holograms, one determines the wavefronts needed to reconstruct an object; this is not done directly in the present invention. Instead, one determines the wavefronts at an observer window that would be generated by a real object located at the same position of the reconstructed object. One can then back-transforms these wavefronts to the hologram to determine how the hologram needs to be encoded to generate these wavefronts. A suitably encoded hologram can then generate a reconstruction of the three-dimensional scene that can be observed by placing one's eyes at the plane of the observer window and looking through the observer window.

Abstract: The invention relates to a method and device for tracking the sweet spots of a sweets spot unit for a transmissive electronic display. The aim of the invention is to improve the reproduction quality and the uniformity of illumination in displays of this type. The display contains a sweet spot unit consisting of an illumination matrix (1) and reproduction elements, in addition to an image matrix (4). Once the position of at least one observer's eye (6) has been determined by a control unit using inverse ray tracing, address data for activating illumination elements (LE) of the illumination matrix (1) is provided from the position data in order to prepare the defined sweet spots (5) for said observer's eye (6). To improve the reproduction quality, an additional optical component is used in ray path for the inverse ray tracing process.

Abstract: A method of computing a hologram for reconstructing an object using a display device. The display device enables a holographic reconstruction of the object. The display device includes a light source and an optical system to illuminate a hologram-bearing medium being encodable with the hologram. The method includes the steps of: (a) computing the hologram by determining the wavefronts at an approximate observer eye position that would be generated by a real version of the object to be reconstructed; and (b) encoding the computed hologram in the hologram-bearing medium.

Abstract: A device for holographic reconstruction of three-dimensional scenes includes optical focusing means which directs sufficiently coherent light from light means to the eyes of at least one observer via a spatial light modulator that is encoded with holographic information. The device has a plurality of illumination units for illuminating the surface of the spatial light modulator; each unit comprises a focusing element, and a light means that emits sufficiently coherent light such that each of these illumination units illuminates one separate illuminated region of the surface, whereby the focusing element and the light means are arranged such that the light emitted by the light means coincides close to or at the observer eyes.

Abstract: A method for generating video holograms for a holographic reproduction device with at least one light modulation means, wherein a scene split into object points is encoded as a whole hologram and can be seen as a reconstruction from a visibility region, which is located within a periodicity interval of the reconstruction of the video hologram. The visibility region, together with each object point of the scene to be reconstructed, defines a subhologram and the whole hologram is generated from a superposition of subholograms, wherein in a sequence of image contents the difference subholograms of object points are preferably generated for each picture, differing in regards to the visibility according to the viewer position in sequential images of the sequence. The display device comprises means that provide high-quality video holograms in spite of the data amount being significantly reduced.

Abstract: A holographic reconstruction system is disclosed with spatial light modulation means, modulating interferable light waves from light sources with at least one video hologram, comprising optical focusing means, focusing the modulated light waves with the reconstructed object light points for at least one eye position for the eyes of observers and controllable electro-optical deflector means, which direct the focused modulated light waves with the reconstructed light points to at least one eye position in order to reduce the aberrations. The reconstruction system has the optical focusing means in a field of focusing elements, wherein each focusing element is provided with at least one interferable light source. The electro-optical deflector means lie in the light path of the interferable light waves after the optical focusing mean and have at least one field of deflector elements, which has at least one separately controllable electro-optical deflector element for each focusing element.

Abstract: A method is disclosed for rendering and generating color video holograms for a holographic reproduction device having at least one light modulation means, wherein a scene divided into object points is encoded as a whole hologram and which can be seen from as a reconstruction a visibility region, which is located within a periodicity interval of the reconstruction of the video hologram. The visibility region defines a subhologram together with each object point of the scene to be reconstructed and the whole hologram is formed from a superposition of subholograms, wherein a 3D rendering graphic pipeline structures a scene represented by image data with depth information into object points and determines and provides at least color and depth information for the object points.

Abstract: A mobile telephony system comprising a calling party mobile telephone with an imaging system and a display. The imaging system is operable to capture an image of the calling party. The calling party mobile telephone sends an image of the calling party to a called party mobile telephone over a wireless link, and the called party mobile telephone locally generates a holographic reconstruction of the calling party using a holographic display that is encoded with a hologram. An advantage is that a mobile telephone call may be held in which one party views a holographic reconstruction of the other party.

Abstract: Holographic display device comprising a first EASLM and a second EASLM, the pair permitting independent modification of phase and amplitude, in which holographic reconstruction is visible through one or more virtual observer windows. An advantage is that an observer may view a holographic reconstruction through one or more virtual observer windows from a device housing a pair of EASLMs which permit independent modification of phase and amplitude.

Abstract: A holographic reconstruction system is disclosed for the three-dimensional reconstruction of object light spots of a scene, comprising spatial light modulation elements which modulate interference-capable light waves of illumination means with at least one video hologram, and optical focussing elements which focus the modulated light waves with the reconstructed object light spots for at least one eye position of the observer's eyes. An electro-optical deflection element controlled by a system controller focuses the modulated light wave with the reconstructed object light spots on at least one eye position and tracks them when the eye position changes. The electro-optical deflection element is a controllable optical diffraction grating with a variable surface relief structure consisting of separately controllable microcells.

Abstract: A holographic display device comprises an OLED array writing onto an OASLM, the OLED array and OASLM forming adjacent layers. The OASLM encodes a hologram and a holographic reconstruction is then generated by the device when an array of read beams illuminates the OASLM. The OASLM is suitably controlled by the OLED array. An advantage of the device is that it lends itself to compactness.

Abstract: A holographic projection system with a display screen and an optical wave tracking element for controlling the direction of propagation of a modulated wave uses a position controller and an eye finder. An extremely wide tracking range is realized in the projection system for simultaneous viewing of the reconstruction by multiple observers, which are situated beside one another. The reconstruction of the scene is reconstructed for each eye position of an observer such that the entire scene is visible in the visibility region in a large tracking range with minimal errors. The projection system reconstructs the scene with the help of modulated partial waves. Projection element(s) direct these partial waves with separately holographically reconstructed segments of the scene at the desired eye position through a structure of screen segments which are at least horizontally staggered on the display screen.

Abstract: A method of computing a hologram for reconstructing an object using a display device. The display device enables a holographic reconstruction of the object. The display device includes a light source and an optical system to illuminate a hologram-bearing medium being encodable with the hologram. The method includes the steps of: (a) computing the hologram by determining the wavefronts at an approximate observer eye position that would be generated by a real version of the object to be reconstructed; and (b) encoding the computed hologram in the hologram-bearing medium.

Abstract: A holographic reconstruction system having spatial light modulators, an eye finder and a position control orients a propagating spatially modulated light wave field toward at least one eye position of an observer's eye, thereby reconstructing a scene in a three-dimensional manner and tracking the same during a position change of the eye position. Unobstructed lateral and axial movement of the observer head to arbitrary eye positions in a tracking region is enabled. The use of additional, planar optical components, which bring about optical aberrations during a position change of observer eyes, are prevented.

Abstract: The invention relates to an interface and circuit arrangement, in particular for transmitting digital image data to at least one holographic encoding unit (HEU), which generates complex hologram values from image data containing depth information and/or encodes the pixel values for controlling at least one light modulator element of a holographic reproduction device. The invention is characterized in that the interface transmits the depth map of the image data and the color map of said image data separately via transmission means (L1, L2) and communication protocols, said depth map comprising the depth information and the color map the color information of scanned images in an image sequence.

Abstract: The invention relates to a controllable illumination device for an autostereoscopic or holographic display, which illumination device contains an illumination matrix of primary light sources having at least one luminous element per light source and a controllable light modulator (SLM) and a reproduction matrix. A computer-generated hologram (CGH) illuminated by the primary light sources (11, . . . , 1n) is coded on the controllable light modulator (SLM) and generates, in at least one plane downstream of the SLM, a matrix—reconstructed from the computer-generated hologram (CGH)—of secondary light sources (2) having a secondary light distribution for the purpose of illuminating the reproduction matrix (4) and for the purpose of focussing in light bundles onto each eye of the viewer via an imaging matrix. The CGH is calculated and reconstructed on the basis of the number of and the positions of the viewers and the system parameters.

Abstract: A video holographic display device includes a light source used to illuminate a hologram-bearing medium encoded with a hologram. The device operates so that only when an observer's eyes are positioned approximately at the image plane of the light source can the holographic reconstruction be seen properly. This contrasts with conventional holographic displays, in which the observer's eyes do not have to be at the image plane in order for a holographic reconstruction to be seen.

Abstract: A holographic reconstruction system and method for the three-dimensional reconstruction of object light points of a scene. The system includes spatial light modulation means which modulate light waves capable of interference with at least one video hologram, focusing means which focus the modulated light waves so that a viewer can view the reconstructed object light points of the scene from a visibility region that is thereby produced by focusing, and deflection means which position the visibility region by aligning the modulated light waves. The holographic reconstruction system includes deflection control means for controlling the deflection means to sequentially adjust the visibility region to different contiguous viewing positions, and light controlling means for switching the light waves in synchronicity with the deflection control means.