Imaging apparatus and methods using diffraction-based illumination are disclosed. An example apparatus includes a diffraction grating to redirect light from a light source toward a sample to thereby illuminate the sample. The example apparatus also includes an image sensor to detect a diffraction pattern created by the illuminated sample.

An apparatus and method to produce a hologram of an object includes an electromagnetic radiation assembly configured to receive a received electromagnetic radiation, such as light, from the object. The electromagnetic radiation assembly is further configured to diffract the received electromagnetic radiation and transmit a diffracted electromagnetic radiation. An image capture assembly is configured to capture an image of the diffracted electromagnetic radiation and produce the hologram of the object from the captured image.

The present disclosure discloses an imaging system, method, and apparatus for identifying information of a hidden object. A light source generates a first beam of narrow-band light and a second beam of narrow-band light that has temporal fluctuations correlated with the first beam. The first beam is directed towards a first scattering surface and the second beam is directed towards a second scattering surface. The first scattering surface scatters the first beam to a scattered light that illuminates a hidden object, the hidden object reflects at least a portion of the scattered light towards the second scattering surface, the reflected light interferes with the second beam and produces an interference pattern on the second scattering surface. An image sensor detects irradiance of the interference pattern on the second scattering surface. An image processor calculates a complex-valued light field that represents information of the hidden object based on the detected irradiance of the interference pattern on the second scattering surface.

The invention relates to a method of creation of three-dimensional alignment patterns that includes providing a layer of optically recordable and polarization sensitive material having a thickness that is greater than, or equal to, a predefined thickness, and concurrently illuminating the optically recordable medium with two coherent beam of same or different polarization with predetermined angle between the beams such that the said beams impinge from the same side or from the opposite sides upon the layer of the recordable material. The invention further relates to polarization volume holograms based on the said alignment patterns and polarization holographic element including a single layer or a stack of several layers of optically recordable materials containing single or multiple polarization volume holograms.

Techniques to improve image quality in holography utilizing lenses made from materials with non-quantized anisotropic electromagnetic properties, such as birefringent materials, to advantageously split an incoming beam of light into two coincident beams with different focal lengths that interfere with one another and thus create holograms free of electro-optical or pixelated devices are disclosed. Corresponding systems, methods and apparatuses are described.

The inventors have discovered a method to improve image quality in holography and, for the first time, utilize lenses made from birefringent materials to advantageously split an incoming beam of either coherent or incoherent light into two coincident beams with different focal lengths that interfere with one another and thus create holograms free of electro-optical or pixelated devices. This discovery has many advantages over current methods to create holograms in which many components, including multiple lenses, other electro-optical devices, and/or beam paths are necessary to create holograms. The current invention provides a purely optical holographic process which has better performance and holographic simplicity, in addition to being able to miniaturize holographic processes more than is currently possible in state of the art holography systems.

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 phase plate, a computer and an opaque mask in some embodiments of the invention.

A method for determining the validity of a parallax image, including: receiving a parallax image's captured two-dimensional image having at least three target identifiers, wherein at least two target identifiers are located at different depth planes in the parallax image; identifying at least three target identifiers in the parallax image's captured two-dimensional image and determining spatial relationship between at least three target identifiers in the two-dimensional image of the parallax image; comparing the spatial relationship of at least three target identifiers in the parallax image's captured two-dimensional image against a predetermined spatial relationship of at least three target identifiers that indicates authenticity; and adjudicating the authenticity of the parallax image based on the degree of difference between spatial relationship of at least three target identifiers in the parallax image's captured two-dimensional image and the predetermined spatial relationship of at least three target identifiers.

An infrared imaging system includes a phase grating overlying a two-dimensional array of thermally sensitive pixels. 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.

Systems and methods for recording holographic gratings in accordance with various embodiments of the invention are illustrated. One embodiment includes a holographic recording system including a first movable platform configured to support a first plurality of waveguide cells for exposure, at least one master grating, and at least one laser source configured to provide a set of recording beams by directing light towards the at least one master grating, wherein the first movable platform is translatable in predefined steps along at least one of two orthogonal directions, and wherein at each the predefined step at least one waveguide cell is positioned to be illuminated by at least one recording beam within the set of recording beams.