An imaging system includes a phase grating overlying a two-dimensional array of pixels, which may be thermally sensitive pixels for use in infrared imaging. The phase grating comprises a two-dimensional array of identical subgratings that define a system of Cartesian coordinates. The subgrating and pixel arrays are sized and oriented such that the pixels are evenly distributed with respect to the row and column intersections of the subgratings. The location of each pixel thus maps to a unique location beneath a virtual archetypical subgrating. Portions of the phase grating extend beyond the edges of the pixels array to interference pattern in support of Fourier-domain imaging.

A method for three-dimensional imaging of a sample (302) comprises: receiving (102) interference patterns (208) acquired using light-detecting elements (212), wherein each interference pattern (208) is formed by scattered light from the sample (302) and non-scattered light from a light source (206; 306), wherein the interference patterns (208) are acquired using different angles between the sample (302) and the light source (206; 306); performing digital holographic reconstruction applying an iterative algorithm to change a three-dimensional scattering potential of the sample (302) to improve a difference between the received interference patterns (208) and predicted interference patterns based on the three-dimensional scattering potential; wherein the iterative algorithm reduces a sum of a data fidelity term and a non-differentiable regularization term and wherein the iterative algorithm includes a forward-backward splitting method alternating between forward gradient descent (108) on the data fidelity term and backward gradient descent (110) on the regularization term.

To obtain a more accurate image by improving a utilization efficiency of light energy while at the same time suppressing with a simpler method distortion that may occur in an inline hologram when a plurality of lights having different wavelengths are used, an observation device (1) according to the present disclosure includes a light source part (11) in which a plurality of light emitting diodes (101) having different light emission wavelengths with a length of each light emission point being smaller than 100λ (λ: light emission wavelength) are arranged such that a separation distance between the adjacent light emitting diodes is equal to or smaller than 100λ (λ: light emission wavelength); and an image sensor (13) installed so as to be opposed to the light source part with respect to an observation target object.

This application relates to a see-through head-mounted display using recorded substrate-guided holographic continuous lens (SGHCL) and a microdisplay with narrow spectral band source or laser illumination. The high diffraction efficiency of the volume SGHCL creates very high luminance of the virtual image.

An in-line holographic microscope can be used to analyze a video stream to track individual colloidal particles' three-dimensional motions. The system and method can provide real time nanometer resolution, and simultaneously measure particle sizes and refractive indexes. An assay using the holographic microscope for holographic particle characterization directly detect viruses, antibodies and related targets binding to the surfaces of specifically functionalized micrometer-scale colloidal probe beads. The system detects binding of targets by directly measuring associated changes in the bead's diameter without the need for downstream labeling and analysis.

A polarization holographic microscope system is disclosed. The polarization holographic microscope system can acquire a birefringence image and a three-dimensional phase image with high sensitivity by aperture synthesis of sample beams at various angles, and a sample image acquisition method using the microscope system.

An electromagnetic wave phase/amplitude generation device includes a radiation unit configured to radiate electromagnetic waves of a random radiation pattern on a spatial frequency in which a state of the electromagnetic waves to be radiated for each divided region is determined to an imaging object, an imaging unit configured to generate a captured image by imaging scattered electromagnetic waves that are electromagnetic waves generated when the imaging object scatters the electromagnetic waves of the radiation pattern radiated by the radiation unit, and a generation unit configured to generate information indicating at least a phase and amplitude of the electromagnetic waves from the imaging object by performing an arithmetic sparsity constraint operation according to sparsity of the imaging object on the basis of the captured image generated by the imaging unit, information indicating the radiation pattern, and information indicating a signal of the imaging object.

A holographic imaging device is disclosed. In one aspect, the holographic imaging device comprises an imaging unit comprising at least two light sources, wherein the imaging unit is configured to illuminate an object by emitting at least two light beams with the at least two light sources. A first and second light beams have different wave-vectors and wavelengths. The holographic imaging device further comprises a processing unit configured to obtain at least two holograms of the object by controlling the imaging unit to sequentially illuminate the object with respectively the first light beam and the second light beam, construct at least two 2D image slices based on the at least two holograms, wherein each 2D image slice is constructed at a determined depth within the object volume, and generate a three-dimensional image of the object based on a combination of the 2D image slices.

A method for defect inspection of a transparent substrate comprises utilizing a wavefront reconstruction unit to obtain complex defect diffraction wavefront of a transparent substrate; using a complex defect diffraction module to confirm the effective diffraction distance of the complex defect diffraction wavefront; utilizing a defect detection module to detect position of the defect of the transparent substrate; using a defect classification module to perform extraction, analysis and classification of diffraction characteristics and utilizing a machine learning algorithm or a deep learning algorithm to automatically identify the defects.

A rotational geometric phase hologram has geometric phase optical elements (GPOEs) serially cascaded along a common optical axis to form a GPOE cascade used for receiving a linearly-polarized light beam and generating output light beams at an exit surface of the last GPOE. Interference occurred in the output light beams creates a polarization interference pattern on the exit surface. A photoalignment substrate, when positioned in close proximity to the exit surface, records the pattern. Advantageously, each GPOE is rotatable about the common optical axis. Respective rotation angles of the GPOEs are determined according to a spatially-varying linear polarization orientation distribution selected to be generated for the polarization interference pattern. Particularly, the respective rotation angles are reconfigurable to provide the periodicity required for the spatially-varying linear polarization orientation distribution over a range of allowed periodicities while keeping the periodicity of spatially-varying optic axis orientation distribution of each GPOE to be fixed.