Method and system for lensless, shadow optical imaging. Formation of a hologram shadow image having higher spatial resolution and lower noise level is accomplished by processing image information contained in multiple individual hologram shadow image frames acquired either under conditions of relative shift between point light source and the detector of the system or under stationary conditions, when system remains fixed in space and is devoid of any relative movement during the process of acquisition of individual image frames.

A device and method for forming an image of a sample includes illuminating the sample with a light source; acquiring a plurality of images of the sample using an image sensor, the sample being placed between the light source and the image sensor, no magnifying optics being placed between the sample and the image sensor, the image sensor lying in a detection plane, the image sensor being moved with respect to the sample between two respective acquisitions, such that each acquired image is respectively associated with a position of the image sensor in the detection plane, each position being different from the next; and forming an image, called the high-resolution image, from the images thus acquired.

Architecture and designs of modulating both amplitude and phase at the same time in spatial light modulation are described. According to one aspect of the present invention, light propagation is controlled in two different directions (e.g., 0 and 45 degrees) to perform both amplitude modulation and phase modulation at the same time in liquid crystals. In one embodiment, a mask is used to form a pattern, where the pattern includes an array of alignment cells or embossed microstructures, a first group of the cells are aligned in the first direction and a second group of the cells are aligned in the second direction. Depending on applications, two cells from the first group and the second group may correspond to a single pixel or two neighboring pixels, resulting in amplitude modulation and phase modulation within the pixel or within an array of pixels.

A holographic display system comprises a light source configured to emit at least partially coherent light; a modulator arranged to be illuminated by the at least partially coherent light and to generate a light field which is a quantised representation of a target light field, H; and a spatial filter delimiting an aperture in a Fourier plane. A Fourier transform of the target light field, F(H), substantially does not overlap (i) a Fourier transform of a complex conjugate of the target light field, F(H*), (ii) a Fourier transform of the target light field multiplied by the complex conjugate of the target light field, F(HH*), (iii) a Fourier transform of a square of the target light field, F(H.sup.2), and (iv) a Fourier transform of a square of the complex conjugate of the light field F(H*.sup.2). The aperture substantially corresponds to F(H) in the Fourier plane.

The present invention relates to a system and method for displaying and capturing holographic true 3D images. The system comprises elements which may form both a wide viewing angle holographic true 3D display and a holographic true 3D video camera. The system mainly comprises a light source, a spatial light modulator or an electro-optical capturing device in different embodiments of the invention, a curved mirror, a computer and a beam splitter and opaque mask in some embodiments of the invention.

Laser 3D imaging techniques include splitting a laser temporally-modulated waveform of bandwidth B and duration D from a laser source into a reference beam and a target beam and directing the target beam onto a target. First data is collected, which indicates amplitude and phase of light relative to the reference beam received at each of a plurality of different times during a duration D at each optical detector of an array of one or more optical detectors perpendicular to the target beam. Steps are repeated for multiple sampling conditions, and the first data for the multiple sampling conditions are synthesized to form one or more synthesized sets. A 3D Fourier transform of each synthesized set forms a digital model of the target for each synthesized set with a down-range resolution based on the bandwidth B.

Sparse nanophotonic arrays (NPAs) and holographic displays comprise a rectangular footprint including an active pixel area, wherein the active pixel area includes a plurality of light-emitting elements arranged in a starburst shape, and wherein a total number of the plurality of light-emitting elements in the active pixel area is equal to a predetermined fraction of a total resolution of a dense nanophotonic array having the rectangular footprint.

A method of imaging a sample having birefringent crystals (or other materials) using a lens-free polarized microscopy device includes illuminating the sample contained on a sample holder with circularly polarized partially coherent or coherent light and capturing lower resolution holographic images of the birefringent crystals with an image sensor. A polarization analyzer unit made from a /4 retarder and a linear polarizer is positioned between the sample holder and the image sensor. The lower resolution holographic images are obtained with the polarization analyzer unit in two different orientations (e.g. 90 orientations). Phase-retrieved, higher resolution images of the birefringent crystals at the different orientations are obtained using the lower resolution holographic images. A differential image is generated from the respective phase-retrieved, higher resolution images. An object support mask is applied to identify the birefringent crystals which can then be pseudo-colored.

A method for digital holographic microtomography comprises (a) providing at least one wavefront controlling device for driving a sample to be rotated and/or an incident beam scanning the sample, (b) utilizing a digital holographic access unit for recording the transmitted or reflected wavefronts of the sample, (c) utilizing a digital holography reconstructing method for reconstructing the transmitted or reflected wavefronts of the sample, and (d) utilizing a tomographic reconstruction approach for reconstructing three dimensional image information of the sample.

An ultra high-resolution near infrared brain imager system includes a modular cap housing closely spaced multiple vertical-cavity surface-emitting laser-single-photon avalanche photodiode array (VCSEL-SPAD) modules, each one of the VCSEL-SPAD modules including a linear VCSEL array and a SPAD detector.