Methods and devices for coherent holographic data channel techniques. Coherent techniques for data detection generally include homodyne and heterodyne detection. Techniques for quadrature homodyne detection, resampling quadrature homodyne detection, n-rature homodyne detection, and spatial wavefront demodulation. Coherent detection techniques in turn enable coherent channel modulation techniques such as phase modulation (including binary phase shift keying, or BPSK; phase quadrature holographic multiplexing, or QPSK; and quadrature amplitude modulation, or QAM). Coherent detection may also enable or improve the performance of other channel techniques such as partial response maximum likelihood (PRML), the various classes of extended PRML, and of noise-predictive maximum likelihood (NPML) detection.

A volume holographic imaging system, apparatus, and/or method enables the projection of a two-dimensional (2D) slice of a four-dimensional (4D) probing object. A 4D probing source object is illuminated to emit or scatter an optical field. A holographic element having one or more recorded holograms receives and diffracts the optical field into a diffracted plane beam having spectral information. A 4-f telecentric relay system includes a pupil filter on the relayed conjugate plane of the volume hologram and images the pupil of the volume hologram onto the front focal plane of the collector lens. A collector lens focuses the diffracted plane beam to a 2D slice of the 4D probing source object. The focused 2D slice is projected onto a 2D imaging plane. The holographic element may have multiple multiplexed holograms that are arranged to diffract light from the corresponding slice of the 4D probing source object.

A volume holographic imaging system, apparatus, and/or method enables the projection of a two-dimensional (2D) slice of a four-dimensional (4D) probing object. A 4D probing source object is illuminated to emit or scatter an optical field. A holographic element having one or more recorded holograms receives and diffracts the optical field into a diffracted plane beam having spectral information. A 4-f telecentric relay system includes a pupil filter on the relayed conjugate plane of the volume hologram and images the pupil of the volume hologram onto the front focal plane of the collector lens. A collector lens focuses the diffracted plane beam to a 2D slice of the 4D probing source object. The focused 2D slice is projected onto a 2D imaging plane. The holographic element may have multiple multiplexed holograms that are arranged to diffract light from the corresponding slice of the 4D probing source object.

A method and apparatus for measuring a quality of a holographic image are provided. An image quality measuring method may include acquiring a first image including a holographic image in a background, and a second image that does not include a holographic image, the first image and the second image being on the same background, extracting a gray level value and a dark-noise counted level value from the first image in a selected range of the first image, extracting a gray level value and a dark-noise counted level value from the second image in the same range as the selected range of the first image, and determining a holographic contrast ratio (HCR) of the holographic image based on the extracted gray level values and the extracted dark-noise counted level values.

The invention concerns an optical system (10) comprising: a spatial light modulator (13) comprising an array of controllable elements adapted for generating a modulated light beam (17) by diffracting an incident light beam (12), the modulated light beam (17) comprising a modulated part and an unmodulated zero order part, the modulated part carrying an image to be projected into a replay volume (18), a control unit for applying a control signal to the controllable elements so as to control the modulated light beam (17) generated by the controllable elements, a perturbing optical element (30) for introducing optical aberrations in the incident light beam (12) and/or the modulated light beam (17) so as to spread the unmodulated zero order part of the modulated light beam in the replay volume (18), the perturbing optical element (30) generating distortions in the image to be projected, wherein the control signal comprises an image signal component carrying data representative of the image to be projected and a correction signal component representative of a correction pattern for correcting the distortions generated by the perturbing optical element (30) in the image to be projected.

Disclosed are a hologram reading device and a hologram reading method, the hologram reading device including a hologram element having a hologram pattern, a detector configured to detect a reflection beam generated in the hologram pattern, and a controller connected to the detector and configured to read information the hologram pattern using a detection signal of the reflection beam, wherein the hologram pattern may have the width or diameter smaller than 225 nm.

In an approach to security for displayed confidential holographic objects, one or more computer processors receive a request from a user to display a holographic object in association with a device. One or more computer processors identify content to be moved to the holographic object. One or more computer processors determine the content includes confidential information. One or more computer processors request authentication from the user. One or more computer processors receive the authentication from the user. One or more computer processors create a holographic boundary, where the holographic boundary blocks a view of the holographic object from one or more unauthorized users. One or more computer processors display the holographic boundary. One or more computer processors display the holographic object in association with the device.

A new diversity concept is provided for achieving accurate phase retrieval with a single shot acquisition. Multiple irradiance data are obtained by a diffractive grating or CGH designed to generate multiple diffraction orders with different diversity values. The effective filters associated with the individual diffraction orders from the diffractive grating or CGH are calculated. The effective filters are extracted by numerical propagation, and they preferably include both real and imaginary values, which signify both absorption and phase shift versus position in the filter plane. The reconstruction process utilizes accurate knowledge of the effective filters for each diffraction order for high quality reconstruction of the extrinsic phase.

One embodiment of a display system includes one or more light sources, one or more spatial light modulators, and a plurality of scatterers. One embodiment of a method for displaying content includes computing at least one of a phase or an amplitude modulation associated with two-dimensional (2D) or three-dimensional (3D) content, and causing one or more spatial light modulators to modulate light based on the at least one of a phase or an amplitude modulation to generate modulated light, where the modulated light is scattered by a plurality of scatterers.

Systems and method disclosed herein include, among other features, receiving an image for display within a display area of a display system, determining a first image component of the image, calculating a hologram of the image, displaying the hologram on a display device and spatially modulating light in accordance with the displayed hologram, and propagating the spatially modulated light through a pupil expander arranged to provide a plurality of different light propagation paths for the spatially modulated light from the display device to the viewing area, wherein each light propagation path corresponds to a respective continuous region of the image owing to the angular distribution of light from the hologram.