G03H2222/20

Coherent optical holographic imaging

A holographic imaging system may include an optical source configured to output a source beam, a splitter configured to split the source beam into a reference beam and an object beam that is incident on a target to form a scattered object beam, and a pre-filter comprising a telecentric lens and a spatial filter. The pre-filter may be configured to receive the scattered object beam and filter diffuse light from the scattered object beam to form a filtered scattered object beam. The system may also include a combiner configured to combine the filtered scattered object beam with the reference beam to form an interference beam, and an imaging array configured to receive the interference beam and generate raw holographic data based on the interference beam.

Holographic device

A holographic security or identification device (10) comprises an object, or a flexible substrate (12) configured to be conformable to a desired, curved shape; and a plurality of structures (14) formed on or in the object to have a desired curved configuration, or formed in or associated with the substrate and arranged to adopt a desired curved configuration when the substrate is conformed to a desired shape, wherein the plurality of structures (14) are configured to receive light (20) of a selected at least one wavelength or range of wavelengths and to produce, using the received light, a desired holographic image (22) for security or identification purposes when in the desired configuration.

HOLOGRAPHIC DISPLAY SYSTEM AND METHOD

A holographic display comprises: an illumination source which is at least partially coherent; a plurality of display elements positioned to receive light from the illumination source and spaced apart from each other, each display element comprising a group of at least two sub-elements; and a modulation system associated with each display element and configured to modulate at least a phase of each of the plurality of sub-elements.

HOLOGRAPHIC DISPLAY SIMULATION DEVICE AND METHOD
20220229953 · 2022-07-21 ·

A holographic display simulation device and a holographic display simulation method are provided. A holographic display simulation device includes a processor; and a memory including one or more instructions, wherein the one or more instructions are executed by the processor, and a holographic display is simulated by using at least one of a light source part model, a spatial light modulator model, and a display optical system model that respectively model a light source part, a spatial light modulator, and a display optical system of the holographic display.

COHERENT SKEW MIRRORS

Systems and methods for performing coherent diffraction in an optical device are disclosed. An optical device may include a grating medium with a first hologram having a first grating frequency. A second hologram at least partially overlapping the first hologram may be provided in the grating medium. The second hologram may have a second grating frequency that is different from the first grating frequency. The first and second holograms may be pair-wise coherent with each other. A manufacturing system may be provided that writes the pair-wise coherent holograms in a grating medium using a signal beam and a reference beam. Periscopes may redirect portions of the signal and reference beams towards a partial reflector, which combines the beams and provides the combined beam to a detector. A controller may adjust an effective path length difference between the signal and reference beams based on a measured interference pattern.

Coherent optical holographic imaging

A holographic imaging system may include an optical source configured to output a source beam and a splitter configured to split the source beam into a reference beam and an object beam that may be incident on a target to form a scattered object beam. The system may also include a combiner configured to combine the filtered scattered object beam with the reference beam to form an interference beam, an imaging array configured to receive the interference beam and generate frames of raw holographic data based on measurements of the interference beam over time, and an image data processor. The image data processor may be configured to receive the frames of raw holographic data from the imaging array, remove data components within the frames that are associated with the particle motion having a motion frequency that is less than a movement frequency threshold to form conditioned raw holographic data, and generate an image based on the conditioned raw holographic data.

Method and an imaging system for holographic imaging

Example embodiments relate to methods and imaging systems for holographic imaging. One embodiment includes a method for holographic imaging of an object. The method includes driving a laser using a current which is below a threshold current of the laser. The method also includes illuminating the object using illumination light output by the laser. Further, the method includes detecting an interference pattern formed by object light, having interacted with the object, and reference light of the illumination light.

Method and apparatus for carrying out a time-resolved interferometric measurement

An embodiment of the invention relates to a method for carrying out a time-resolved interferometric measurement comprising the steps of generating at least two coherent waves, overlapping said at least two coherent waves and producing an interference pattern, measuring the interference pattern for a given exposure time, thereby forming measured interference values, and analyzing the measured interference values and extracting amplitude and/or phase information from the measured interference values. In at least one time segment, hereinafter referred to as disturbed time segment, of the expo-sure time, the interference pattern is intentionally disturbed or destroyed such that the corresponding measured interference values describe a disturbed or destroyed interference pattern. In at least one other time segment, hereinafter referred to as undisturbed time segment, of the exposure time, the interference pattern is undisturbed or at least less disturbed compared to the disturbed time segment such that the corresponding measured interference values describe an undisturbed or less disturbed interference pattern. The measured interference values that were measured during the entire given exposure time, are filtered, wherein those interference values that were measured during the at least one disturbed time segment, are reduced, suppressed or discarded. The filtered interference values are analyzed and the amplitude and/or phase information is extracted from the filtered interference values.

Holographic display

Disclosed is a holographic display including a spatial light modulator (SLM) with pixels, the SLM pixels being on a substrate, the SLM including circuitry which is on the same substrate as the SLM pixels, the circuitry operable to perform calculations which provide an encoding of the SLM.

HOLOGRAPHIC DISPLAY SYSTEM AND METHOD
20210333756 · 2021-10-28 ·

A holographic image display system comprising a processor receiving image data at an input and producing output hologram data based on the image data. The image data comprises three-dimensional image data that is separable into a plurality of two-dimensional image layers at different image planes. The processor is configured to: a) perform a space-frequency transform on each image layer to provide a transformed image layer, b) apply a focus factor to each transformed image layer, c) apply a pseudo-random phase factor to each transformed image layer, and d) sum the transformed image layers to form a holographic sub-frame, e) repeat steps (c) and (d) for a plurality of iterations, applying a different pseudo-random phase factor to the transformed image layers in each iteration to form a plurality of holographic sub-frames; and f) drive a spatial light modulator with the holographic sub-frames in rapid temporal succession to generate a holographic image.