Abstract: Techniques related to generating holographic images are discussed. Such techniques include application of a hybrid system including a pre-trained deep neural network and a subsequent iterative process using a sui table propagation model to generate diffraction pattern image data for a target holographic image such that the diffraction pattern image data is to generate a holographic image when implemented via a holographic display.

Abstract: A wearable display with coherent replication of optical beams is presented. The display includes a replication element comprising a plurality of features configured to receive and split impinging light into a plurality of sub-beams for propagation in a plurality of directions. At least a portion of the split sub-beams propagating in a direction of an eyebox of the NED form an image by optical interference.

Abstract: A holographic communication system and method can include: determining a user parameter for one or more users, generating a set of views based on the user parameter, and displaying the set of generated views.

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 hologram display device includes a light source unit that emits light, a spatial light modulator that modulates the light emitted from the light source unit, and a random pinhole panel. The random pinhole panel includes a plurality of pinholes of a random position or a random size and is arranged in line with an output part of the spatial light modulator. In the hologram display device and the method of manufacturing the hologram display device, a position and size of a random pinhole on the random pinhole are not limited to inside each pixel of the spatial light modulator.

Abstract: Disclosed is a method for generating a digital hologram representing a 3D scene including an object, an object being defined by points and their associated intensity. For each object, a prior step of calculating an “omnidirectional” angular spectrum of the light field emitted by an object in the scene on the surface of a geometric solid centered on the object, a surface of the solid being sampled according to a predetermined grid, a sample of the grid being associated with a vector frequency; for the scene, the following steps: —obtaining a pose of an observer in the world frame of reference; —deriving the hologram from the scene as a function of the pose obtained from the “multidirectional” angular spectra calculated for each object. The step of calculating an angular spectrum of the light field for each object of the scene takes into account predetermined viewing directions.

Abstract: The projection device includes a light source, a liquid crystal on silicon (LCoS) panel, and a circuit. The circuit is configured to obtain a target image including a target pattern, and generate two content images. Each content image includes a duplicated pattern of the target pattern, and the duplicated patterns are off-axis shifted to the same coordinate when performing a computer-generated hologram (CGH) algorithm, so as to generate a phase image. The LCoS panel is driven according to the phase image to display a reconstructive image at a reconstructive distance.

Abstract: Provided are methods of processing a holographic image and apparatuses using the methods. A method includes obtaining image data with respect to a three-dimensional (3D) object, obtaining interference patterns in a computer-generated hologram (CGH) plane by performing a Fourier transform on the image data, and generating a CGH with respect to the 3D object based on the interference patterns, wherein the Fourier transform is performed based on a focal length of an eye lens of an observer.

Abstract: A method of generating three-dimensional (3D) shape information of an object to be measured from an image including intensity information of an object hologram generated by interference between a reference light reflected from an optical mirror and an object light affected by the object includes checking at least one frequency component included in the image and extracting real image components corresponding to a real image from the frequency component. The method also includes generating a correction light and a real image hologram based on the real image components, generating an intermediate hologram based on the correction light, and generating curvature aberration correction information from the intermediate hologram. The method further includes generating a correction hologram based on the curvature aberration correction information and generating the 3D shape information of the object from the correction hologram.

Abstract: A transparent holographic diffuser screen that diffracts the light beams of a digital light projector, which focuses a real image in the plane of the aforementioned transparent holographic diffuser screen, which redirects the light to an eyebox at a pre-determined viewing position generating as a set of diffracted diffused beams that can be seen from the eyebox as a flat in-plane image. The transparent holographic diffuser screen may be used to provide either a highest luminance or a largest eyebox. Potential applications include use for automotive applications, which may include applications for displaying videos, playing games, and video conference apps.

Abstract: A head worn imaging system includes a light source configured to generate a light beam. The system also includes a light guiding optical element having a thickness between 0.1 and 1.5 mm and configured to propagate at least a portion of the light beam by total internal reflection. The system further includes an entry portion and an exit portion of the light guiding optical element configured to selectively allow light addressing the exit portion to exit the light guiding optical element based on the angle of incidence of the light, the radius of curvature of the light and/or the wavelength of the light.

Abstract: An ultrasonic apparatus (100) for creating a holographic ultrasound field (1) comprises an ultrasound source device (10) being adapted for creating an ultrasound wave, and a transmission hologram device (20) having a transmission hologram (21) and an exposed acoustic emitter surface (22), said transmission hologram device (20) being acoustically coupled with the ultrasound source device (10) and being arranged for transmitting the ultrasound wave through the acoustic emitter surface (22) and creating the holographic ultrasound field in a surrounding space, wherein the acoustic emitter surface (22) is a smooth surface which do not influence the field distribution of the ultrasound wave. Furthermore, a method of creating a holographic ultrasound field in an object (3), wherein the ultrasonic apparatus (100) is used, and applications of the ultrasonic apparatus (100) are described.

Abstract: There is provided a spatial light modulator arranged to display a light modulation pattern including a hologram. The spatial light modulator includes a liquid crystal on silicon spatial light modulator having a plurality of pixels. The hologram has a plurality of pixels. The spatial light modulator includes a silicon backplane. Each pixel of the spatial light modulator includes a light-modulating element and a respective pixel circuit. Each pixel circuit is embedded in the silicon backplane. Each pixel circuit is arranged to drive the corresponding light-modulating element. Each pixel circuit is further arranged to combine a received pixel value of the hologram with a corresponding pixel value of the light processing function such that the light modulation pattern further includes the light processing function. The light processing function includes a lens function and/or a grating function.

Abstract: There is provided a driver for a spatial light modulator. The spatial light modulator comprises [m×n] pixels. The driver is arranged to receive input holograms each comprising [x×y] pixels, wherein m?x and n?y. The driver is further arranged to drive the spatial light modulator to display thereon output holograms each comprising [m×n] pixels by tiling each input hologram onto the pixels of the spatial light modulator to form an output hologram corresponding to each input hologram using a tiling scheme. The driver is arranged to use a first tiling scheme to display a first output hologram and a second tiling scheme to display a second output hologram. Each output hologram comprises a plurality of tiles of the input hologram. Each tiling scheme defines the size of each tile and the position of each tile on the pixels of the spatial light modulator.

Abstract: A head-up display for a vehicle, the head-up display including a picture generating unit arranged to generate a picture on a light receiving surface; and an optical system arranged to image the picture, where the optical system includes an input arranged to receive light of the picture; an output arranged to output light forming an image of the picture; a first mirror and second mirror arranged to guide light from the input to the output along an optical path, where the optical path includes a first optical path from the input to the second mirror including a transmission through the first mirror; and second optical path from the second mirror to the output including a reflection off the first mirror.

Abstract: A system for lens-free imaging includes a processor in communication with a lens-free image sensor. The processor is programmed to operate the image sensor to obtain a hologram ??. The processor is further programmed to generate, from the hologram, a reconstructed image X and phase W at a focal depth z using an assumption of sparsity.

Abstract: Provided are on-axis and off-axis digital hologram generating device and method. The on-axis and off-axis digital hologram generating device includes an object phase generator configured to access a phase file of an object stored in a storage device and generate object phase information from the phase file of the object; a digital object light generator configured to generate digital object light information based on a light property of object light input by a user and the object phase information generated by the object phase generator; a digital reference light generator configured to generate digital reference light information based on a light property of reference light input by the user; and a digital hologram generator configured to generate a digital hologram based on hologram property information input by the user, the digital object light information generated by the digital object light generator, and the digital reference light information generated by the digital reference light generator.

Abstract: A method and apparatus for processing hologram image data capable of optimizing image quality of a hologram image are provided. The image processing method includes receiving input image data, reading a header included at a predetermined location in the input image data, and generating hologram data configured to display a hologram image by performing a Fourier calculation and pixel encoding on the input image data based on at least one parameter recorded in the header, wherein the at least one parameter recorded in the header includes at least one of depth information, scale information, and gamma information.

Abstract: A three-dimensional (3D) image display apparatus is provided. The apparatus includes a plurality of light sources; a spatial light modulator configured to modulate light from the plurality of light sources according to 3D image information; and a focusing optical system configured to focus an image formed by the spatial light modulator onto a focal plane. The plurality of light sources may be arranged such that multiple focal points, respectively corresponding to the plurality of light sources, are formed on the focal plane near a pupil of a user.

Abstract: A method for digital holography includes modeling a hologram using a forward propagation model that models propagation of a light field from a hologram plane to an image plane. The method further includes computing the hologram as a solution to an optimization problem that is based on the model. The method further includes configuring at least one spatial light modulator using the hologram. The method further includes illuminating the spatial light modulator using a light source to create a target image.

Abstract: A laser apparatus comprising an aperture module array including two or more aperture modules, each aperture module of the array being optically couple-able to a source of coherent electromagnetic radiation and configured to emit a beam of radiation received from the source. The apparatus emits a composite beam comprising beams emitted by the respective aperture modules and modulates at least one of the beams in power and phase relative to at least one other of the beams such that a desired non-uniform composite beam profile is provided.

Abstract: An optical device includes a spatial light modulator and an optical waveguide with a plurality of extraction features. The plurality of extraction features is positioned relative to the optical waveguide so that a respective extraction feature receives light, having propagated within the optical waveguide, in a first direction and directs a first portion of the light in a second direction distinct from the first direction to exit the optical waveguide and illuminate at least a portion of the spatial light modulator. The plurality of extraction features is also positioned relative to the optical waveguide so that a respective extraction feature directs a second portion, distinct from the first portion, of the light to undergo total internal reflection, thereby continuing to propagate within the optical waveguide.

Abstract: Systems and methods are described that enable a 3D telepresence. In an exemplary method, a 3D image stream is generated of a first participant in a virtual meeting. A virtual meeting room is generated. The virtual meeting room includes a virtual window, and the 3D image stream is reconstructed in the virtual window. The first participant thus appears as a 3D presence within the virtual window. The virtual meeting room may also include virtual windows providing 3D views of other participants in the virtual meeting and may further include avatars of other meeting participants and/or of the first meeting participant.

Abstract: Holographic and diffractive optical encoding techniques for forming reflection or transmission holograms. The encoding device includes a substrate having an interference pattern that can propagate light along a light propagation path from one side of the substrate to another side of the substrate. Furthermore, an optical element may be used to propagate light according to a four-dimensional light field coordinate system.

Abstract: Methods and apparatus for forming a three-dimensional article in which a powdered medium is distributed in a powder bed, heated to a temperature below its melting point, and fused by means of a laser beam projected in the form of an image of a cross section of the three-dimensional article. The image of the cross-sectional layer is created by spatial light modulation of the laser beam using an LCoS display. During the fabrication process, characteristics of the image of the cross-sectional layer are controlled through monitoring of the projection of a holographic representation of the image using one or more imaging devices.

Abstract: A holographic display system includes a light source that emits coherent light; a lateral displacement beam splitter that optically receives the coherent light and generates first reference light and second reference light; a first spatial light modulator (SLM) and a second SLM that optically receive the first reference light and the second reference light respectively, and construct first phase-only function (POF) light and second POF light respectively; a first beam splitter and a second beam splitter that optically receive the first POF light and the second POF light respectively, and generate first split light and second split light respectively; and a plurality of polarizers disposed between the first SLM and the first beam splitter, and between the second SLM and the second beam splitter, respectively.

Abstract: A method to incorporate multiple independent optical correlators into one system. By “independent optical correlator,” we mean an optical correlator comprising of an input SLM, filter SLM, and camera, combined with appropriate coherent illumination and Fourier transforming lenses. By “one system” we mean a single optical system which utilises the elements of each of the independent correlators multiple times.

Abstract: An illuminating apparatus for a display screen with a transmissive image generator, having a free-viewing mode and a restricted-viewing mode, comprising a background illuminator radiating light in a wide angular range, a plate-shaped light guide in front of the background illuminator with outcoupling elements, and light sources. Outcoupling element dimensions are smaller than the width and height of subpixels of the image generator, parts of the surface of two outcoupling elements are below each subpixel and the filling factor of the outcoupling elements is maximally 50% of the large surface of the light guide, and at least 80% of the light coupled out is radiated within an angular range of 60°, and more than 50% of the light is radiated away from or toward the background illuminator, and in the restricted mode, the background illuminator and light sources are off, and in the free-viewing mode, the background illuminator is on.

Abstract: There is provided a method of projection using an optical element (502,602) having spatially variant optical power. The method comprises combining Fourier domain data representative of a 2D image with Fourier domain data having a first lensing effect (604a) to produce first holographic data. Light is spatially modulated (504,603a) with the first holographic data to form a first spatially modulated light beam. The first spatially modulated light beam is redirected using the optical element (502,602) by illuminating a first region (607) of the optical element (602) with the first spatially modulated beam. The first lensing effect (604a) compensates for the optical power of the optical element in the first region (607). Advantageous embodiments relate to a head-up display for a vehicle using the vehicle windscreen (502,602) as an optical element to redirect light to the viewer (505,609).

Abstract: Aspects of the technology provide a graphical display on a client device such as a smartwatch or other electronic display device. Content rendered by a non-emissive display element is augmented by an enhancement display element, for instance to change a color or illumination intensity of the content. The enhancement display element may include multiple illumination sources and light pipes that guide light from the light sources to specific regions along the display. Alternatively, the enhancement display element may be a transparent OLED or similar component, for instance to provide per-pixel illumination, highlighting and/or color enhancement to selected content items. In yet another configuration, the enhancement display element has a mask layer and a light element. The mask layer controls the amount of light reaching the non-emissive display element or viewable by a user. Each of these architectures provides rich enhancement to the content items generated by the non-emissive display element.

Abstract: A display apparatus includes a display panel including a display area configured to display an image, and a non-display area, at least one first sound generator in the display area, and at least one second sound generator in the non-display area, wherein each of the at least one first sound generator and the at least one second sound generator is configured to vibrate the display panel to generate sound toward a front of the display panel.

Abstract: A two-step optimization process is utilized to define an optimal phase profile for a LCoS spatial light modulator. The two-step optimization process first utilizes a nonlinear constrained optimization (NCO) program to determine the specific parameters required to obtain an optimal phase profile (hologram), where the “optimal phase profile” is typically defined as that profile which achieves maximum diffraction efficiency for optical switching. Following this first step, phase scaling (and perhaps an adjustment in the number of pixels per period) is employed to slightly modify the values of the optimal phase profile to effectively suppress crosstalk peaks. If any orders still exhibit an unacceptable level of crosstalk, these orders are then subtracted from the phase profile to create the final design.

Abstract: In the present invention, by providing an apparatus for generating a hologram based on human visual system modeling, including a lens configured to focus light emitted from a three-dimensional (3D) object, a sensor configured to detect the light, an object information obtaining unit configured to obtain object information of the 3D object based on information of the lens and a confusion circle size threshold value corresponding to information of the sensor, and a hologram image generating unit configured to generate a hologram image for the 3D object based on the object information, it is possible to provide a method of generating a hologram based on a human visual system capable of generating image information of a three-dimensional object faster and capable of generating a higher-quality hologram image.

Abstract: There is provided a lighting device arranged to produce a controllable light beam for illuminating a scene. The device comprises an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light. The device further comprises Fourier optics arranged to receive phase-modulated light from the spatial light modulator and form a light distribution. The device further comprises projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam.

Abstract: The present description may provide a method of generating a hologram measurement pattern for measuring image quality of holographic display, including: generating a test pattern and a common pattern including at least one grayscale bar; generating measurement pattern data by combining the common pattern with a frame of the test pattern; and generating the hologram measurement pattern by inserting a random phase into the measurement pattern data and an apparatus applied thereto, thereby more accurately measuring the quality of the 3D holographic image reproduced by the holographic display.

Abstract: A holographic display apparatus includes: a light source configured to emit light; a spatial light modulator configured to sequentially generate hologram patterns for modulating the light and to sequentially reproduce frames of hologram images based on the hologram patterns; and a controller configured to provide hologram data signals to the spatial light modulator, the hologram data signals being used to sequentially generate the hologram patterns. The controller is configured to further provide, to the spatial light modulator, diffraction pattern data signals for forming periodic diffraction patterns for adjusting locations of the hologram images to be reproduced on a hologram image plane, the diffraction pattern data signals being configured to move the periodic diffraction patterns on the spatial light modulator along a predetermined direction for each of the frames.

Abstract: Provided is a method for converting a hologram resolution of an apparatus for converting a hologram resolution. The apparatus for converting a hologram resolution includes receiving a hologram data and determining a direction and a height of an envelope for the hologram data based on first information associated with the hologram data. The apparatus for converting a hologram resolution includes converting the resolution of the hologram data from a first resolution into a second resolution based on the envelop having the determined direction and height.

Abstract: According to one embodiment, there is provided an optical film with a recording surface, the recording surface including: a computation element section in which a phase component of light from each reconstruction point of a reconstructed image is computed, the computation element section corresponding to each reconstruction point one by one; a phase angle recording area in which a phase angle computed based on the phase component is recorded; and a phase angle non-recording area in which the phase angle is not recorded, the phase angle computed based on the phase component being recorded in an overlapping area where the computation element section and the phase angle recording area overlap each other.

Abstract: A method of creating a 3D holographic display in a device having a camera, holographic projectors and display surface, the method including: tracking by the camera an interactive device over the display; determining by the camera a distance from the interactive device to the display; responsive to an action by the interactive device, visually displaying by the holographic projectors a unit holographic object proximate to the interactive device; responsive to one or more additional actions by the interactive device, visually displaying by the holographic projectors additional unit holographic objects proximate to the unit holographic object so as to be visually displaying a plurality of unit holographic objects; accumulating by the holographic projectors the plurality of unit holographic objects proximate to the display surface; and determining an amount of accumulated unit holographic objects visually displayed by the holographic projectors until a resultant shape of holographic objects is formed.

Abstract: The disclosure provides a display system and a method for displaying a virtual image to a viewer An optical system of the disclosure includes a spatial light modulator, a light source, a Fourier transform lens, a viewing system and a processing system. The spatial light modulator is arranged to display holographic data in the Fourier domain, illuminated by the light source. The Fourier transform lens is arranged to produce a 2D holographic reconstruction in the spatial domain corresponding to the holographic data. The viewing system is arranged to produce a virtual image of the 2D holographic reconstruction. The processing system is arranged to combine the Fourier domain data representative of a 2D image with Fourier domain data representative of a phase only lens to produce first holographic data, and provide the first holographic data to the optical system to produce a virtual image.

Abstract: An image sensor has a plurality of pixels arranged in an array on an imaging surface and converts a captured optical image into an image signal. A modulator is provided on a light receiving surface of the image sensor and modulates the light intensity using a grating pattern. An image processor performs image processing of the image signal output from the image sensor. The modulator has a grating substrate and a first grating pattern is formed on a first side of the grating substrate adjacent to a light receiving side of the image sensor. The grating pattern is composed of a plurality of concentric circle patterns. Each concentric circle pattern has concentric circles having a pitch which becomes smaller in inverse proportion to the distance from the center thereof. The plurality of concentric circle patterns do not overlap with each other in the grating pattern.

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: An apparatus and a method for laser beam shaping and scanning. The apparatus includes a digital micromirror device (DMD) including a plurality of micromirrors, configured to receive a first laser beam, adjust an axial position of a focal point of the first laser beam along a moving direction of the first laser beam by controlling a focal length of wavefront of a binary hologram applied to the DMD, and adjust a lateral position of the focal point on a plane perpendicular to the moving direction by controlling a tilted angle of a fringe pattern and a period of fringes of the binary hologram applied to the DMD, wherein the DMD simultaneously functions as programmable binary mask and a blazed grating.

Abstract: A stereoscopic display device may include a light control panel on a display panel, so that light emitted from the display panel may emit in a direction different from adjacent frame and the visibility of the stereoscopic image which is provided to user may be increased without the deterioration of the resolution.

Abstract: A method for lens-free imaging of a sample or objects within the sample uses multi-height iterative phase retrieval and rotational field transformations to perform wide FOV imaging of pathology samples with clinically comparable image quality to a benchtop lens-based microscope. The solution of the transport-of-intensity (TIE) equation is used as an initial guess in the phase recovery process to speed the image recovery process. The holographically reconstructed image can be digitally focused at any depth within the object FOV (after image capture) without the need for any focus adjustment, and is also digitally corrected for artifacts arising from uncontrolled tilting and height variations between the sample and sensor planes. In an alternative embodiment, a synthetic aperture approach is used with multi-angle iterative phase retrieval to perform wide FOV imaging of pathology samples and increase the effective numerical aperture of the image.

Abstract: A projection device is provided with at least: a laser light source which emits laser light; a conversion unit which converts the laser light into parallel light; a phase-modulation-type spatial modulation element which phase-modulates the parallel light on the basis of a supplied projection image and delivers phase-modulated light; and a control unit. The control unit includes: a projection image storage unit in which at least one projection image group is stored; a processing unit which, with respect to one projection image acquired from the projection image storage unit in synchronism with an update period, generates a combination of a plurality of diffraction patterns in the update period; and a projection image generation unit which supplies the combination of a plurality of diffraction patterns to the phase-modulation-type spatial modulation element as the supplied projection image.

Abstract: A display system includes a data provider, a spatial light modulator and a second cylindrical lens. The data provider is arranged to provide holographic data comprising first data corresponding to a first cylindrical lens having optical power in a first direction. The spatial light modulator is arranged to receive the holographic data, wherein the spatial light modulator is arranged to spatially-modulate received light in accordance with the holographic data. The second cylindrical lens is arranged to receive spatially-modulated light from the spatial light modulator and perform a one-dimensional Fourier transform of the received light in a second direction orthogonal to the first direction.

Abstract: A display system may comprise a radially symmetric mirror, a display screen, and a radial array of lenticular lenses. The mirror may be a frustum of a cone. Light from the screen may pass through the radial array and then reflect from the mirror, to create a 360-degree automultiscopic display. The automultiscopic display may display multiple rendered views of a 3D scene, each of which shows the scene from a different virtual camera angle. Which rendered view is visible may depend on the angular position of a user. Each lenticular lens may be wedge-shaped and may have a constant focal length and a constant height-width ratio. In some cases, slices from some, but not all, of the rendered views are displayed under any single lenticular lens at a given time. The lenticular array may be replaced by a holographic optical element, or by radial array of parallax barriers.

Abstract: A method that includes: recognizing by an object recognition device a physical object; comparing by the object recognition device the physical object with a fully completed object; identifying by the object recognition device a spatial position, an orientation and physical dimensions of the partially-completed physical object; creating by a three-dimensional (3D) modeling program a 3D model of the partially-completed physical object using the spatial position, the orientation and physical dimensions of the partially-completed physical object; inputting by the 3D modeling program to a holographic creation system a missing shape of the partially-completed physical object, the missing shape being a complementary portion of the partially-completed physical object; creating by the holographic creation system a 3D hologram of the complementary portion; displaying by a holographic projector the 3D hologram of the complementary portion adjacent to the partially-completed physical object.

Abstract: A method for processing a sequence of holographic images with a view to playing the images back on a holographic display device to at least one viewer. A subset of wavelet coefficients relevant for the reconstruction of a sub-hologram visible for the at least one viewer from at least one viewing point is selected from a decomposition of at least one holographic image on a wavelet basis and information representative of a location of the at least one viewer in a repository of the display device. In the method, decomposition of the at least one holographic image is carried out on a Shannon wavelet basis.