A method for learned hardware-in-the-loop phase retrieval for holographic near-eye displays includes generating simulated ideal output images of a holographic display. The method further includes capturing real output images of the holographic display. The method further includes learning a mapping between the simulated ideal output images and the real output images. The method further includes using the learned mapping to solve for an aberration compensating hologram phase and using the aberration compensating hologram phase to adjust a phase pattern of a spatial light modulator of the holographic display.

Methods of performing a complex Fourier transform of a complex data set corresponding to an image are disclosed. The methods comprise receiving a complex data set and performing a first 1D complex Fourier transform in the complex data set in Cartesian form; converting the complex data set into polar form and compressing the complex data set in polar form; performing a row-column transformation of the complex data set; decompressing the complex data set and converting the complex data set back into Cartesian form; and performing a second 1D Fourier transform in the complex data set in Cartesian form, wherein the second 1D complex Fourier transform is orthogonal to the first 1D complex Fourier transform. Corresponding systems are also disclosed, as are application to the iterative computation of computer-generated holograms.

A liquid crystal on silicon spatial light modulator comprising an array of light-modulating pixels and a controller are disclosed. Each light-modulating pixel of the array comprises liquid crystal and is associated with a respective flip-flop. The controller receives a hologram of an image comprising a plurality of hologram pixels. Each hologram pixel comprises a respective n-bit hologram pixel value. The controller drives each light-modulating pixel in accordance with a respective hologram pixel value of the hologram. There is a one-to-n pixel correlation between the hologram and the light-modulating pixels. The flip-flops of each contiguous group of n light-modulating pixels are connected in series to form a shift register. During operation of the shift register, the n-bit hologram pixel value associated with each contiguous group of n light-modulating pixels is provided to each light-modulating pixel one bit at a time over the course of at least n clock cycles.

Disclosed are a method and a system for processing a computer-generated hologram (CGH). The system for processing a CGH includes a CGH generation apparatus and a display apparatus. The CGH generation apparatus repeatedly performs a process of propagating object data from a first depth layer to a second depth layer, changing amplitude data of the object data to second predefined amplitude data, back-propagating the object data from the second depth layer to the first depth layer, and changing the amplitude data of the object data to first predefined amplitude data, and generates a CGH by using the object data.

A display system and a method of adjusting a display system are disclosed. A first plurality of pixels is arranged to display a first hologram, receive light of a first wavelength, and output spatially-modulated light according to the first hologram, along a first optical path. A first Fourier transform lens on the first optical path forms a first holographic reconstruction at a replay plane. A second plurality of pixels is arranged to display a second hologram, receive light of a second wavelength, and output spatially modulated light according to the second hologram, along a second optical path. A second Fourier transform lens on the second optical path forms a second holographic reconstruction at the replay plane. A first optical element on the first optical path is arranged to receive the output light from a first part of the first optical path and direct it along a second part of the first optical path to the replay plane. A second optical element on the second optical path is arranged to receive the output light of the second wavelength from a first part of the second optical path and direct it along a second part of the second optical path to the replay plane. The length of the first part of the first optical path is not equal to the length of the first part of the second optical path. The first part of the first optical path may he substantially collinear with the first part of the second optical path.

Briefly stated, technologies are generally described for providing a computer-generated holography (CGH). Example devices/systems described herein may use one or more of a server device and/or a client device. The server device may be configured to provide CGH data to a client device including a holographic image display unit. The server device may receive information on the holographic image display unit from the client device, calculate the CGH data from three-dimensional image data and the information on the holographic image display unit, and/or transmit the CGH data to the client device. The client device may be configured to provide a holographic image. The client device may reconstruct the holographic image on the holographic image display unit using CGH data and a reconstruction beam, transmit information on the holographic image display unit to the server device, and/or receive the CGH data from the server device.

Disclosed are a method and a system for image processing and data transmission in a network-based multi-camera environment. The inventive concept provides a real-time high-efficiency 3D/hologram image service to the user through an in-network computing technology. In detail, the inventive concept minimizes loss of a quality of a final 3D/hologram image while reducing an amount of information that is to be transmitted through processing of a plurality of cameras by allowing information captured by the cameras to be efficiently processed and transmitted when the cameras cooperate with each other to produce a 3D/hologram image.

A system includes a plurality of optical identifiers and a reader for the optical identifiers. Each optical identifier has an optical substrate and a volume hologram (e.g., with unique data, such as a code page) in the optical substrate. The reader for the optical identifiers includes an illumination source (e.g., a laser), and a camera. The illumination source is configured to direct light into a selected one of the optical identifiers that has been placed into the reader to produce an image of the associated volume holograms at the camera. The camera is configured to capture the image. The captured image may be stored in a digital format by the system.

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.

An apparatus and method for processing a holographic image are disclosed. The apparatus calculates a first calculation result with respect to an image for the left eye and a first calculation result with respect to an image for the right eye and stores the results at different memory addresses of a storage. Thereafter, the apparatus calculates values of a waveform of light to be modulated by a spatial light modulator by performing a second calculation that uses all of the first calculation results stored in the storage. An image window of the image for the left eye and an image window of the image for the right eye are spatially separated from each other by the apparatus in a viewing window of a hologram image reproduced via the spatial light modulator.