Abstract: An optical device for directing illuminating light at a pixel matrix and/or at a controllable spatial light modulator of a display, in particular of a stereoscopic or holographic 3D display comprises a multitude of reflection elements which work according to the principle of a concave mirror and which direct the illuminating light at the pixel matrix and/or at the controllable spatial light modulator of the display, and/or comprises at least one transmission element which is designed in the form of a holographic optical element, in particular in the form of a holographic volume grating, which directs the illuminating light at the pixel matrix and/or at the controllable spatial light modulator of the display.

Abstract: A method for reducing speckle patterns of a three-dimensional holographic reconstruction is disclosed. A controllable light modulator into which a hologram of a three-dimensional scene is coded is illuminated by coherent light, a reconstruction lens transforms the modulated light into an eye position and reconstructs the three-dimensional scene in a reconstruction space and a control means controls the illumination. This provides a holographic reproduction device in which the speckle patterns occurring during reconstruction of a three-dimensional scene are reduced. According to one embodiment, a next-to-real time method is presented using a carrier medium of conventional image refresh rate.

Abstract: A method for reducing speckle patterns of a three-dimensional holographic reconstruction is disclosed. A controllable light modulator into which a three-dimensional scene is coded is illuminated by coherent light, a reconstruction means projects the modulated light close to an eye position into a space of observation and a control means controls the illumination. This provides a holographic reproduction device in which the speckle patterns occurring during reconstruction of a three-dimensional scene are reduced. Also provided is a next-to-real time method using a carrier medium of conventional image refresh rate.

Abstract: A backplane device for a spatial light modulator for generating a two-dimensional and/or three-dimensional representation of a scene or of content. The spatial light modulator includes pixels having pixel addresses and being electronically controllable by the backplane device for assigning pixel values to the pixels. The backplane device comprises at least one electrode for each pixel, at least one analog line and at least one pixel addressing means. Such a pixel addressing means comprises x-addressing lines and y-addressing lines. Every pixel is connected to an analog line, to an x-addressing line and to a y-addressing line. As a pixel value assigning scheme a generating means is adapted to generate a voltage characteristic to be applied to the at least one analog line such that the voltage characteristic depends on the pixel values to be assigned to the pixels.

Abstract: A direction-controlled illumination unit for an autostereoscopic display, which unit deflects light from activated illumination elements through a transmissive image reproduction means in the space in front of the display into visibility areas, from which a stereoscopic and/or monoscopic representation can be seen. The direction-controlled illumination unit contains an illumination means having illumination elements, an imaging means having imaging elements, a prism arrangement, a light-scattering means and an image reproduction means. A respective imaging element is assigned a number of illumination elements in order to deflect light in the form of a beam onto observers' eyes in a sequential manner in terms of time.

Abstract: This invention relates to a holographic projection device with an array of mirror elements in the form of micro-mirrors. The holographic projection device comprises at least one light modulator device, which contains the array of mirror elements, for an enlargement of a reconstruction space for a reconstructed scene. Each mirror element is coupled with at least one actuator. The actuators tilt the corresponding mirror elements and/or displace them axially in at least one direction. Thereby, a wave front for the representation of a reconstructed scene is directly modulated. The holographic projection device comprises an optical system for the projection of the modulated wave front into at least one observer window in an observer plane.

Abstract: A method for generating video holograms is disclosed, principally for a holographic reproduction device, having at least one light modulator in which a scene which is deconstructed into object points is encoded as a complete hologram and can be viewed as a reconstruction from a visibility region. A 3D-rendering graphic pipeline determines color and depth information for the object points of the scene, from which a holographic pipeline determines the complex hologram values.

Abstract: In a holographic projection apparatus a virtual visibility region is magnified, for observing a reconstructed scene with at least one light modulation device and with at least one light source having sufficiently coherent light for generating a wavefront of a scene that is coded in the light modulation device. By means of imaging the wavefront into a viewer plane, it is possible to generate the virtual visibility region for observing the reconstructed scene. The virtual visibility region has at least two virtual viewer windows. In this case, the virtual viewer windows are dimensioned such that the reconstructed scene can always be observed without tracking of the viewer windows upon movement of a viewer in the viewer plane.

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.

Abstract: A holographic projection system has an optical wave tracking system which adjusts the propagation direction of a modulated wavefront. It provides an adjustable wave tracking system which aligns the modulated wave with a desired eye position of one or more observers and follows the movements of the observer. The system comprises spatial light modulation means which modulate a wave with holographic information for the purpose of holographic reconstruction. The optical wave tracking provides the light path of the modulated wave with a desired propagation direction which guides the modulated wave out of the reconstruction system via a light exit position of a display screen. Position control means set adjustable tracking mirror means in terms of their inclination to a reflection direction for reflecting the modulated wave and deflection means, which are located in the set reflection direction, reflect the wave via the display screen into the desired propagation direction.

Abstract: The present invention relates to a method and device for the generation of reconstructions of information encoded on spatial light modulators by way of illumination with coherent incident waves. The invention includes the following steps: Splitting of the incident wave into at least two incident sub-waves, Modulation of the incident sub-waves with the help of selected apodization functions so to form modulated incident sub-waves, Direction of the modulated incident sub-waves towards the corresponding, spatially separated and pixel-matrix-shifted spatial light modulators, Diffraction of the modulated incident sub-waves at the encoded pixels of the respective spatial light modulators, Additive combination of the sub-waves emitted by the respective spatial light modulators to form one common emitted wave, and Transformation of the emitted wave into the Fourier plane with the help of a projection system.

Abstract: An apparatus for recording holograms on an optical medium, in particular on an optically addressable spatial light modulation device is disclosed. For this purpose, the apparatus comprises an illumination device for emitting light, an optical medium, an image source having at least one modulation element, and an arrangement of microlenses. In this case, the arrangement of microlenses is arranged at a distance from the optical medium in such a way that the image focal points of the microlenses lie on the optical medium, such that the hologram can be generated on the optical medium.

Abstract: A controllable device for phase modulation of coherent light with modulator cells comprising liquid crystal molecules is provided which realizes a large number of phase steps per modulator cell and whose switching delay is shorter than 1 ms. The device can include a spatial light modulator with a modulator matrix having regularly arranged controllable LC modulator cells, a light source which illuminates the modulator matrix, and control means for controlling the phase modulation in the LC modulator cells. The modulator matrix can be configured to comprise a controllable ?/2 plate disposed between two non-controllable ?/4 plates; the controllable LC modulator cells can be PSS liquid crystal; each LC modulator cell is controllable locally with a positive or negative voltage value, depending on the actual phase values to be written; and the control means generate a globally constant phase offset for the phase values to be written in every other frame.

Abstract: An optical unit for dynamically shaping a wavefront is disclosed, having light modulation cells disposed regularly in cell fields, and locally influencing partial light waves in a propagating light wavefront. Each cell field is connected to a cell controller separately adjusting the optical behavior of the light modulator cells. Serially-disposed fields, each having modulator cells, are located in the light path of the light wavefront. Cell control means adjust the modulator cells in a first cell field such that the modulator cells discretely implement a phase shift having a continuous phase value, and in a second cell field such that the modulator cells implement a prism function having a continuous directional value for the partial light waves. A focusing means for the emitted wavefront is also located in the light path of the optical unit, guiding the partial light waves at an output pupil of the optical unit.

Abstract: The invention relates to a holographic reconstruction system for the reconstruction of scenes having at least one video hologram modulated wave front, and an enlarged visibility region. The system utilizes two-dimensional coded light modulator cells of spatial light modulation means and optical focusing means, which realize a Fourier transformation of the modulated wave front in their focal plane. First optical deflection means deflect the parallel disposed partial light waves such that their Fourier transformations appear as cascading in the focal plane. A spatial frequency filter located on the focal plane, lets each of the same diffraction orders of all modulated partial light waves pass, and second optical deflection means arrange the wave front strips next to each other at the modulated wave front, which reconstructs the scene.

Abstract: A holographic display including a spatial light modulator, and including a position detection and tracking system, such that a viewer's eye positions are tracked, with variable beam deflection to the viewer's eye positions being performed using a microprism array which enables controllable deflection of optical beams.

Abstract: A device for the production of holographic reconstructions having light modulators is disclosed. The device comprises at least one pixelated light modulator illuminated by at least one light source, and a focusing optical element field arrangement which images the light sources in an image plane after the light modulator. For the reconstruction, only one order of diffraction of the Fourier spectrum of the hologram should be used. The light modulator is provided with an assigned filter-aperture field arrangement which is located in the area of the image plane of the light source images and which has a plurality of aperture openings. Said aperture openings are designed in such a way that they each allow the passage of a prespecified area of the overall dimensions either smaller or the same as a diffraction order of the diffraction spectrum following Fourier transformation and produced from the holographic coding of the light modulator.

Abstract: The invention relates to a method for generating video holograms in real time for a holographic reproduction device using at least one light modulator means in which a scene split into object points is encoded as a whole hologram in the form of the reconstruction of a visibility region in a periodicity interval of the reconstruction of the video hologram. The reconstruction of an individual object point only requires part of the whole hologram encoded on the light modulator means. The invention is characterized in that, for each object point, the contributions for propagation of the light waves in the visibility region can be determined from at least one look-up table.

Abstract: An individual, controllable light modulator is configured with a regular pixel structure, for realizing different types of modulation. The spatial light modulator can be realized transmissively and reflectively. The light modulator contains at least one addressable, transmissive layer with a pixel structure and at least one substrate layer with retro-reflecting elements, as well as modulation control means for controlling the modulation of the pixels. The modulation control means produce a number of macropixels from at least two adjacent pixels, to which a selected modulation characteristic is assigned. The retro-reflecting elements are disposed consecutively in such a manner in the substrate layer that, in each case, a retro-reflecting element covers two adjacent pixels of a macropixel of the addressable layer, in order to direct a light bundle, incident in each case on one pixel of a macropixel, sequentially, through further pixels of the macropixel to modulate the incident light bundle.

Abstract: The invention relates to a method for the multimodal representation of image contents on a display unit for video holograms. Said unit comprises at least one or several light sources (LS), an optical system (L), and a spatial light modulator SLM (S) with hologram contents. According to the inventive method, the unit directs the wavefront that an object would emit to the associated eye positions (EP) such that the viewer sees the reconstruction of the scene and different views are presented to the eyes by means of temporal or spatial multiplexing in order to generate the stereo effect.