A system for controlling access to secured resources using a security token having a hologram embossed thereon is provided. A key is split into a user key and a complimentary key based on a mask, wherein key values in the user key correspond to idle state values in the complimentary key and vice versa. The user key is used to generate a user key array, that is used to generate a three-dimensional virtual image that is holographically embossed onto a security token. The hologram is merged with a corresponding hologram for the complimentary key and the combination compared to an image of an ensemble of the key. The combination can be mergers of images or extractions of holograms. If a match is found, within a tolerance, an access grant signal is sent to the secure resources, thereby securing the resources based on presence of the security token.

A system for controlling access to secured resources using a security token having a hologram embossed thereon is provided. A key is split into a user key and a complimentary key based on a mask, wherein key values in the user key correspond to idle state values in the complimentary key and vice versa. The user key is used to generate a user key array, that is used to generate a three-dimensional virtual image that is holographically embossed onto a security token. The hologram is merged with a corresponding hologram for the complimentary key and the combination compared to an image of an ensemble of the key. The combination can be mergers of images or extractions of holograms. If a match is found, within a tolerance, an access grant signal is sent to the secure resources, thereby securing the resources based on presence of the security token.

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.

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.

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.

A three-dimensional imaging system based on a stereo hologram is disclosed. Images composed of sub-images having the same vertical-horizontal resolutions which are generated at plural image projection modules having a two-dimensional arrangement structure are projected to a prism array plate or a transmission-type diffusion plate, and are converted into light points, i.e., image points through a microlens array unit. A diffusion plate used as an image display screen is mounted to a position at which images diffused from the light points intersect with images diffused from the adjacent light points.

An illumination distribution system for distributing high power illumination to a set of projectors. The system includes a display element, such as a spatial light modulator (SLM), receiving light from a laser. The system includes a fiber optic array with connection locations for optical fibers. The system includes projectors that are each coupled to the fiber optic array at one or more of the connection locations with at least one optical fiber. The system includes a controller operating the display element at a first time to display a first hologram and at a second time to display a second hologram differing from the first hologram such that the laser light is split, with equal or unequal splitting ratios, into beams that are selectively directed to the connection locations of the fiber optic array (e.g., based on a 2D routing pattern used to generate the holograms).

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.

Some embodiments are directed to a technique having an off-axis interferometric geometry that is capable of spatially multiplexing at least six complex wavefronts, while using the same number of camera pixels typically needed for a single off-axis hologram encoding a single complex wavefront. Each of the at least six parallel complex wavefronts is encoded into an off-axis hologram with a different fringe orientation, and all complex wavefronts can be fully reconstructed. This technique is especially useful for highly dynamic samples, as it allows the acquisition of at least six complex wavefronts simultaneously, optimizing the amount of information that can be acquired in a single camera exposure. The off-axis multiplexing holographic system of some embodiments provide an off-axis holography modality that is more camera spatial bandwidth efficient than on-axis holography. Moreover, the off-axis interferometric system allows simple simultaneous acquisition of at least six holographic channels, making it attractive for imaging dynamics.