Abstract: Embodiments relate to a sensor system configured to detect physical rotation, entire or relative, of one or more objects and/or their environment and/or proximity of a magnetic field, by measuring the degree of localization of a medium trapped in a ring-shaped artificial lattice. The lattice structure can be configured to comprise of lattice sites distributed with a lattice period around an azimuth of a closed ring. The site depths of the plurality of lattice sites can be configured to be modulated with a modulation period different from the lattice period to affect the onsite energies of each lattice site and the eigenstates of the system. Physical rotation of the sensor and/or the proximity of magnetic field will alter the localization properties so as to cause the degree of localization of the medium to change (e.g., the medium becomes more confined in space or more spread out in space).

Abstract: A totagram is produced by an iterative spectral phase recovery process resulting in complete information recovery using special masks, without a reference beam. Using these special masking systems reduce computation time, number of masks, and number of iterations. The special masking system is (1) a unity mask together with one or more bipolar binary masks with elements equal to 1 and ?1, or (2) a unity mask together with one or more phase masks, or (3) a unity mask together with one pair of masks or more than one pair of masks having binary amplitudes of 0's and 1's, in which the masks in the pair are complementary to each other with respect to amplitude, or (4) one or more pairs of complementary masks with binary amplitudes of 0's and 1's without a unity mask.

Abstract: One embodiment provides a file sharing system. During operation, the system identifies a data file to be sent to a second device of a second user and generates a plurality of coded fragments from the data file based on a generator matrix of erasure encoding. An individual coded fragment does not include plaintext data. The system generates a plurality of sub-files, each of which comprises one or more coded fragments, of the data file. The system attaches a first sub-file to an electronic communication destined to the second device, uploads a second sub-file to a cloud provider, and embeds a link, which may expire and is protected based on a verification code, associated with the uploaded second sub-file into the electronic communication. The system sends the electronic communication to the second device and the verification code in a text message to a cell phone of the second user.

Abstract: An example system includes a bulk steering crystal apparatus having a first lens face and a second concave face. The example bulk steering crystal apparatus further includes a number of steering portions interposed between the first lens face and the second concave face, where each of the steering portions includes a bulk substrate portion including an electro-optical material and a corresponding high-side electrode electrically coupled to the corresponding one of the number of steering portions.

Abstract: The present technology relates to an endoscope apparatus configured to be capable of assisting with setting of an angle of view of immediately before an endoscope is pulled out when the endoscope is pulled out and cleaned and then reinserted during surgery in endoscopic surgery and the like, and a method and program for operating the endoscope apparatus. An image captured by the endoscope apparatus is recorded, a feature value of the image captured is detected, a difference between detected feature values of consecutive images is obtained, and, when the difference is greater than a predetermined threshold value, an index is added to the image captured. Thus, the index is added to an image of immediately before the endoscope is pulled out from a body cavity, and the image is recorded.

Abstract: An illumination optical unit serves for illuminating objects to be examined by a metrology system. The illumination optical unit has an optical pupil shaping assembly for generating a defined distribution of illumination angles of illumination light over an object field in which an object to be examined can be arranged. An optical field shaping assembly for generating a defined intensity distribution of the illumination light over the object field is disposed downstream of the pupil shaping assembly in the beam path of the illumination light. The field shaping assembly has at least one optical field shaping element arranged in the region of a pupil plane of the illumination optical unit. This results in an illumination optical unit which ensures an illumination which can be set in a defined manner with regard to an intensity distribution and an illumination angle distribution over the entire object field.

Abstract: Configurations are disclosed for a health system to be used in various healthcare applications, e.g., for patient diagnostics, monitoring, and/or therapy. The health system may comprise a light generation module to transmit light or an image to a user, one or more sensors to detect a physiological parameter of the user's body, including their eyes, and processing circuitry to analyze an input received in response to the presented images to determine one or more health conditions or defects.

Abstract: Configurations are disclosed for a health system to be used in various healthcare applications, e.g., for patient diagnostics, monitoring, and/or therapy. The health system may comprise a light generation module to transmit light or an image to a user, one or more sensors to detect a physiological parameter of the user's body, including their eyes, and processing circuitry to analyze an input received in response to the presented images to determine one or more health conditions or defects.

Abstract: An imaging system uses a dynamically varying coded mask, such as a spatial light modulator (SLM), to time-encode multiple degrees of freedom of a light field in parallel and a detector and processor to decode the encoded information. The encoded information may be decoded at the pixel level (e.g., with independently modulated counters in each pixel), on a read-out integrated circuit coupled to the detector, or on a circuit external to the detector. For example, the SLM, detector, and processor may create modulation sequences representing a system of linear equations where the variables represent a degree of freedom of the light field that is being sensed. If the number of equations and variables form a fully determined or overdetermined system of linear equations, the system of linear equations' solution can be determined through a matrix inverse. Otherwise, a solution can be determined with compressed sensing reconstruction techniques with the constraint that the signal is sparse in the frequency domain.

Abstract: One embodiment provides a file sharing system. During operation, the system identifies a data file to be sent to a second device of a second user and generates a plurality of coded fragments from the data file based on a generator matrix of erasure encoding. An individual coded fragment does not include plaintext data. The system generates a plurality of sub-files, each of which comprises one or more coded fragments, of the data file. The system attaches a first sub-file to an electronic communication destined to the second device, uploads a second sub-file to a cloud provider, and embeds a link, which may expire and is protected based on a verification code, associated with the uploaded second sub-file into the electronic communication. The system sends the electronic communication to the second device and the verification code in a text message to a cell phone of the second user.

Abstract: A method for determining the complex amplitude of the electromagnetic field associated with a scene, comprising a) capturing a plurality of images of the scene by means of a photographic camera, the images being focused in planes of focus arranged at different distances, wherein the camera comprises a lens of focal length F and a sensor arranged at a certain distance from the lens in its image space, taking at least one image pair from the plurality of images and determining the accumulated wavefront to the conjugate plane in the object space corresponding to the intermediate plane with respect to the planes of focus of the two images of the pair.

Abstract: Fast processing of information represented in digital holograms is provided to facilitate generating a hologram for displaying three-dimensional (3-D) holographic images representative of a 3-D object scene on a display device. A holographic generator component (HGC) can receive or generate visual images, comprising depth and parallax information, of a 3-D object scene. A hologram processor component can apply a first non-uniform transform to a visual image to generate a first signal, and can apply a second transform to the first signal to generate a second signal that corresponds to a hologram that represents the 3-D object scene. The hologram can be illuminated with a light beam to facilitate generating a holographic image(s) that can be a reconstructed image that reconstructs the 3-D object scene. A display component can display the holographic image(s) for viewing by an observer.

Abstract: A VCSEL package including a VCSEL, a housing, containing the VCSEL, and a diffuser operably attached to the housing and configured to receive an emitted beam of light from the VCSEL and produce a beam of predetermined angular divergence. The housing may be a PLLC package, a ceramic package, or a TO-style package. The diffuser could be a substantially planar diffuser sheet, which in some cases may be comprised of glass or plastic. In some embodiments, the diffuser could be a diffractive optical element or holographic light shaping diffuser. In some embodiments, the diffuser can be designed to produce a beam with an illumination full angle of up to about 90 degrees.

Abstract: A recognition method includes receiving an input image; and recognizing a plurality of elements associated with the input image using a single recognizer pre-trained to recognize a plurality of elements simultaneously.

Abstract: A system and apparatus includes an optical masking unit that is configured for applying a user's mask code. The mask code has a code length of at least equal to a number of users. A light source unit is coupled to the optical masking unit. The light source unit includes a number of coherent lasers. The number of coherent lasers is at least equal to half the number of users. Each of the coherent lasers is configured for operation at a different specific prescribed operating frequency. A modulation unit is configured for applying the user's data to the coherent lasers. An optical combiner unit is operable for combining outputs of the coherent lasers to an optical fiber input.

Abstract: Provided are a spatial light modulator (SLM) and a method of fabricating the same. The complex spatial light modulator includes a thin film transistor (TFT) layer provided on a substrate, an amplitude type SLM and a phase type SLM electrically connected to the TFT layer, and a first polarizer provided on the phase type SLM, wherein the TFT layer includes transistors electrically connected to the amplitude type SLM and the phase type SLM, respectively, and the amplitude type SLM and the phase type SLM are commonly and electrically connected to the TFT layer and driven.

Abstract: A method and apparatus for aligning optical components within an optical sensor. A mask with an elongate slot formed therethrough is placed optically between an optical emitter and an optical detector of the sensor. The mask is rotated 180 degrees while the detector output is measured. As the mask is rotated, the output varies. The longitudinal position of the slot that corresponds with the maximum detector output is indicative of the transverse direction that the optical emitter must be moved relative to the optical detector for optimal alignment. A controller may operate a first actuator for translating the optical emitter with respect to the optical detector and a second actuator for rotating the mask, thereby automating the alignment process.

Abstract: A 3D image processing method includes providing image data, generating a first visual angle image and a second visual angle image according to the 3D image data, blurring the first visual angle image, enhancing the second visual angle image, and displaying the blurred first visual angle image and the enhanced second visual angle image. The 3D image processing method reduces a ghost effect when watching 3D images.

Abstract: Methodologies and systems for generating data that can be used to provide 3-D imaging for one or more viewers are described. In some implementations, images and depth information are obtained from objects. Processing systems are disclosed for producing from these images and depth information data that can be used by projectors to project images that appear in 3-D.

Abstract: Methods and devices for holographic imaging are disclosed. In some embodiments, a holographic imaging device is disclosed that includes at least one radiation source, a reflective surface, and an image sensor. The at least one radiation source may be configured to emit a radiation wave towards the reflective surface and an object positioned on or near the reflective surface, where the radiation wave is reflected by the reflective surface to produce a reference wave and is reflected directly toward the image sensor by the object to produce an object wave directed at the image sensor. Further, the image sensor may be configured to determine an interference pattern between the reference wave and the object wave. A holographic image representing the object may be reconstructed based on the interference pattern.

Abstract: A holographic imaging device for imaging an object under study includes a partially reflective surface having a contact side for contacting the object under study and an imaging side for partially reflecting a radiation wave. The device also includes at least one radiation source for projecting the radiation wave onto the imaging side of the partially reflective surface and an image sensor arranged to receive the radiation wave when reflected by the partially reflective surface. The image sensor is adapted for determining an interference pattern between the radiation wave reflected by the imaging side of the partially reflective surface and the radiation wave reflected by the object under study when contacting the contact side of the partially reflective surface.

Abstract: The invention relates to a synthetic hologram (64A) comprising first elementary cells wherein first openings are respectively defined, said hologram being integrated into a first portion of a binary motif (60), said binary motif comprising at least one second portion wherein second elementary cells comprising second openings (66) are defined, said second openings having an average size equal to the average size of the first openings, with a 5% margin, and a random phase shift.

Abstract: A main object of the present invention is to provide a hologram observation sheet with a transmission type hologram formed integrally with other members, to be attached with various members for the use as for example an advertising medium or a decoration member. To achieve the object, the invention provides a hologram sheet comprising: a transparent substrate, a hologram layer formed on the transparent substrate and having a transmission type Fourier transform hologram region having the function of transforming a light beam incident from a point light source to a desired optical image, and a pressure-sensitive adhesive layer.

Abstract: A color filter with parallel, vertical color strips of the RGB base colors associated with the image separating element, the color strips repeating horizontally within the color filter in periodic fashion. The light modulator contains a sequence of two registered holograms for each base color interlaced into six pixel columns for a left observer eye and for a right observer eye, and the sequence is repeated horizontally in periodic fashion. The periods of the color filter and the hologram are arranged relative to one another with the same degree of expansion, with a color strip and at least two pixel columns with holograms of the base color of the color strip are associated with a separating element.

Abstract: The present invention provides a digital hologram recording system and a numerical reconstruction method for a hologram, which are used for capturing an image of an object and recording it as a holographic data. Said system comprises: signal light, formed after irradiating the object with a light source; an image detector, for recording interference fringes of the signal light; and a light pipe, arranged in a path of the signal light and located between the object and the image detector, wherein the light pipe has a reflection surface, and a part of the signal light enters the image detector after reflected by the reflection surface of the light pipe. The present invention can make the collected signal equivalent to several times of the pixel counts of the image detector, thereby able to break through the spatial bandwidth limitation and shortening the amount of time required to measure the hologram.

Abstract: Methods for numerically generating a centered discrete fractional Fourier transform matrix on a computer, the centered discrete fractional Fourier transform matrix of size N by N where N is an odd integer. Centering is obtained by simple barrel roll operations on eigenvectors. High-accuracy is obtained by numerically calculating the eigenvectors of the discrete fractional Fourier transform matrix from a closed-form mathematical formula and then iteratively performing a Gram-Schmidt orthogonalization procedure until a resulting set of improved-orthogonal eigenvectors is produced that is sufficiently orthogonal.

Abstract: A method and apparatus for preparing a digital hologram representing an image of an object includes generating a measurement beam and a first reference beam, irradiating the object by the measurement beam, and guiding the measurement beam reflected to an optical sensor. The method also includes guiding the first reference beam to a first mirror, and guiding the reflected beam to the optical sensor so that both beams generate an interference pattern on the sensor. The method includes providing a digital signal representing the interference pattern on the optical sensor, to obtain a digital hologram, and subjecting the digital hologram to a Fourier transform in the spatial frequency domain to obtain a spectrum. The method further includes replacing a section of a first image term overlapped by a DC-term by a corresponding section of a second image term.

Abstract: A holographic projection device comprises for the reconstruction of scenes at least one light source which emits sufficiently coherent light for the generation of a wave front. Further, the projection device comprises at least one light modulator device containing modulation element, said projection device being of a two-dimensional design. The light modulator device and a scanning element are combined such that the light emitted by the scanning element only scans one one-dimensional arrangement of modulation elements of the two-dimensional light modulator device at a time.

Abstract: A method for correcting mis-focus of an image created from coherent imaging using centered fractional Fourier transforms or mathematical equivalents is described. A received image is presented to a numerical processor, and a first numerical value for a variable ? is selected and used in an iterative algorithm, numerical procedure, system architecture, etc. A centered discrete fractional Fourier transform of power ? and a phase restore operator associated with a centered discrete fractional Fourier transform of power ? are applied to the image file to produce a modified image. A change in mis-focused is determined and used in adjusting ? for a next iteration. If values for ? between 0 and real number ? do not result in a desired outcome, ? is adjusted as a complex value ?+i? where ? is a real number.

Abstract: An apparatus and method to produce a hologram of an object includes an electromagnetic radiation assembly configured to receive a received electromagnetic radiation, such as light, from the object. The electromagnetic radiation assembly is further configured to diffract the received electromagnetic radiation and transmit a diffracted electromagnetic radiation. An image capture assembly is configured to capture an image of the diffracted electromagnetic radiation and produce the hologram of the object from the captured image.

Abstract: The present invention relates to a lens system for an apparatus for reading from and/or writing to holographic storage media, and more specifically to a lens system optimized for an apparatus with a coaxial common aperture arrangement of an object beam and a reference beam. According to the invention, the lens system, which Fourier transforms an object beam and focuses a reference beam into a hologram layer of a holographic storage medium, and which focuses a servo beam onto a servo area of the hologram layer, includes a moving part acting on the object beam, the reference beam and the servo beam, and a fixed part acting only on the servo beam.

Abstract: A holographic projection display for reconstructing a 3D-scene and a coding method that indicates an improvement of the control value of coding through an iterative Fourier transformations-algorithm are disclosed. The display includes a reproduction system including at least two reproducing means. First reproduction means for reproducing the illuminating means and for the Fourier transformation of actual wave fronts modulated in the phase modulator follow a second reproduction means, that functions as a screen. The plane of the screen is a Fourier transformation plane for calculations with the iterative Fourier transformation-algorithm and the plane of the phase modulator is the other Fourier transformation plane.

Abstract: A hologram reproducing apparatus includes a first reference light path leading laser light from a laser light source so that a hologram recording medium is irradiated with first reference light; a diffracted light path leading diffracted light, generated from the hologram recording medium by irradiation with the first reference light, to a light receiving element having a plurality of pixels; and a second reference light path leading second reference light, having the same polarization direction as that of the diffracted light, from the laser light source to the light receiving element. The second reference light path is provided with a phase modulating element so that the phase difference between the diffracted light and the second reference light in a light receiving surface of the light receiving element is adjusted within a predetermined range.

Abstract: An Apparatus and method to produce a hologram of a cross-section of an object includes an electromagnetic radiation assembly configured to receive a received electromagnetic radiation, such as light, from the object. The electromagnetic radiation assembly is further configured to diffract the received electromagnetic radiation and transmit a diffracted electromagnetic radiation An image capture assembly is configure to capture an image of the diffracted electromagnetic radiation and produce the hologram of the cross-section of the object from the captured image. The hologram of the cross-section includes information regarding a single cross-section of the object.

Abstract: The present invention relates to a projection device for holographic reconstruction of scenes, said device comprising at least one light modulator device and at least one light source which emits sufficiently coherent light for the generation of a wave front of a scene, which is encoded in the light modulator device. A Fourier transform (FT) of the light which is emitted by the light source and modulated by the light modulator device is projected by a projection means on to a screen. Further, the wave front which is encoded on the light modulator device is projected by the projection means into at least one virtual observer window in an observer plane. For tracking the observer window according to a change in an eye position of the at least one observer, the inventive device comprises at least one deflection means, which is disposed between the light modulator device and the screen.

Abstract: Method for real-time rendering and generating of computer-generated video holograms from three-dimensional image data with depth information, where the position and viewing direction of an observer defines a view of the scene, and where the observer is assigned with at least one virtual observer window, which is situated in an observer plane near the observer eyes, comprising the following process steps: 3D rendering and generation of the depth map of scene section data between two parallel section planes, which are disposed at right angles to the viewing direction of the observer, transformation of the scene section data, repetition of the steps of 3D rendering and transformation, Back-transformation, encoding in pixel values in order to reconstruct the three-dimensional scene.

Abstract: The invention relates to a method and a playback device for a two- and/or three-dimensional illustration, having at least one light source, at least one light modulation device, a display screen, and a tracking system for tracking a virtual viewer window of a viewer plane, in which at least one viewer is located. This tracking system has a position detection system for determining the eye positions of the at least one viewer in the viewer plane, a tracking device, and a control device for activating and controlling the tracking device, and is disposed between the light modulation device and the display screen. In order to track the viewer window along an optical axis of the playback device, a focal width on the image side of an optical system of the tracking device is constant.

Abstract: A hologram projecting system includes a coherent light source for emitting a reference beam onto a real object; and an image sensor for receiving the reference beam and a scattered beam reflected from the real object, and recording a Fourier image of the real object. Also included is a modulator for receiving the Fourier image. The reference beam is passed through the modulator, and configured to interact with the Fourier image to form a virtual image of the real object. The image sensor includes an n×m pixel array, where n and m are numbers of rows and columns, respectively. The modulator includes an n×m pixel array corresponding to the n×m pixel array of the image sensor. The pixels in the n×m pixel array of the image sensor control transmissivity of light in corresponding pixels of the n×m pixel array of the modulator.

Abstract: The invention relates to method, computer program code and signal processing/image display systems for displaying one or more images using holographic techniques. We describe a method of generating data for displaying an image defined by displayed image data using a plurality of holographically generated temporal subframes, the temporal subframes being displayed sequentially in time such that they are perceived as a single noise-reduced image. The method includes generating from the displayed image data holographic data for each subframe of said set of subframes such that successive replay of holograms defined by said holographic data for said subframes gives the appearance of said image, and wherein the method further includes, when generating said holographic data for a said subframe, compensating for noise in said displayed image arising from one or more previous subframes of said sequence of holographically generated subframes.

Abstract: A three-dimensional image display device is provided which allows a reduction in redundant calculation and high-speed obtainment of an optimum control image to be recorded on an optical wavefront control unit This invention relates to a three-dimensional image display device for displaying a three-dimensional image by irradiating illuminating light at an optical wavefront control unit which records a control image. The three-dimensional image display device of this invention includes a control image optimizing unit which calculates three-dimensional images corresponding to a group of control images based on constraints inherent to the optical wavefront control unit, selects a control image corresponding to a three-dimensional image satisfying a predetermined condition from the group of control images and records the selected control image on the optical wavefront control device.

Abstract: An apparatus for reading a data page from and/or writing a data page to a holographic storage medium includes a common aperture arrangement of one or more reference beams and an object beam or a reconstructed object beam. One or more spatial light modulators are provided for generating the one or more reference beams by modulating a light beam with a modulation pattern having a spatial frequency higher than the spatial frequency of the data page.

Abstract: The invention relates to a hologram that enables two or more different images to be simultaneously reconstructed even in a state where the hologram is fixed in terms of relative position with respect to an eye, and a holographic viewing device that incorporates it. The hologram 14 is fabricated by applying Fourier transform to a plurality of input image to obtain a plurality of corresponding Fourier transform images 13-1, 13-2 and arraying the Fourier transform images 13-1, 13-2 on the same plane according to a given two-dimensional array principle into a computer-generated hologram. When a plurality of point light sources 231 to 239 located behind the hologram 14 are viewed through the hologram 14, a plurality of images are simultaneously and parallel reconstructed (28) in correspondence to the array positions of the plurality of Fourier transform images.

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: A holographic storage system having an improved data page quality is described. The holographic storage system includes a special optical filter or a special light source for emphasizing the high frequency components of a reference beam and/or an object beam. This is achieved by an optical filter arranged in a Fourier plane, which has a higher attenuation at the center than at the edge. Alternatively, an adapted light source for generating the reference beam and/or the object beam is arranged in a Fourier plane. The light beam emitted by the light source has a higher intensity close to the edge than at the center.

Abstract: According to one aspect and example, a holographic recording system includes a light source, an object for modulating an object beam from the light source, and a relay system adapted to magnify (positive or negative) the modulated beam (e.g., an image of the object) to an output image. The object may include an SLM operable to modulate the object beam with an information layer comprising a plurality of data pages. The output image is directed to the holographic storage medium, where a reference beam is also directed, to record the resulting interference pattern. Additionally, the relay system converges the output image to an output Fourier plane, which may be disposed within the holographic storage medium. A filter may be placed at an intermediate Fourier plane located prior to the output Fourier plane, and a phase mask may be placed at the position of the output image.

Abstract: A holographic microscope comprising a source configured to provide a diverging beam of radiation, a beam splitter configured to direct a first portion of the diverging beam towards an object and a second portion of the diverging beam towards a reflector, the beam splitter being further configured to direct an object beam from the object and a reference beam from the reflector towards a transducer, and the transducer being configured to provide a signal indicative of the interference pattern of the object beam and the reference beam incident on the transducer. A method of digital holography is also disclosed.

Abstract: An apparatus and method to produce a hologram of an object includes an electromagnetic radiation assembly configured to receive a received electromagnetic radiation, such as light, from the object. The electromagnetic radiation assembly is further configured to diffract the received electromagnetic radiation and transmit a diffracted electromagnetic radiation. An image capture assembly is configured to capture an image of the diffracted electromagnetic radiation and produce the hologram of the object from the captured image.

Abstract: The invention relates to video holograms and devices for reconstructing video holograms, comprising an optical system having a light source, lens and the video hologram having cells arranged in a matrix or a regular pattern with at least one opening per cell, the phase or amplitude of said opening being controllable. The holographic video representations of expanded spatial objects can be achieved in a wide viewing area in real time using controllable displays, whereby the objects are either computer-generated or created by different means. The space-bandwidth product (SBP) of the hologram is thus reduced to a minimum and the periodicity interval of the Fourier spectrum is used as a viewing window on the inverse transformation plane, through which the object is visible in the preceding space. The mobility of the viewer(s) is achieved by tracking the viewing window.

Abstract: Processing image information includes receiving light having image information. A first optical transform is performed on the light to yield a first optically transformed light, and a second optical transform is performed on the light to yield a second optically transformed light. A first metric is generated in accordance with the first optically transformed light, and a second metric is generated in accordance with the second optically transformed light. The first metric and the second metric are processed to yield a processed metric. An inverse optical transform is performed on the processed metric to process the image information of the light.

Abstract: Hologram recording devices and techniques can be employed to produce wide field-of-view holograms. A lens can be used to couple an object beam into a holographic recording material without substantially changing the angle of incidence of the object beam. When displayed, images from holograms recorded using this technique can have a field-of-view greater than that of the object beam. One or more aspheric reflective surfaces can be used to couple an object beam into a holographic recording material at relatively steep angles.