A method for producing a holographic optical element. The method includes a step of exposing a recording material to a phase pattern which is provided by a first modulated light beam with a first phase portion. Furthermore, the method includes a step of an additional exposure of the recording material to the phase pattern, which is provided by a second modulated light beam with a second phase portion, wherein the second phase portion has a phase offset with respect to the first phase portion in order to produce a holographic optical element.

An apparatus and method for recording a holographic optical element. The apparatus includes a first recording unit configured to provide a first wave front for recording the holographic optical element, a second recording unit configured to provide a second wave front for recording the holographic optical element, and (i) a deformable phase plate configured to perform wave front modulation of the first wave front when the holographic optical element is recorded, or (ii) a plurality of deformable phase plates, at least one deformable phase plate (of the plurality of deformable phase plates can be configured to perform wave front modulation of the first wave front when the holographic optical element is recorded.

A cell area extraction unit (241) extracts a cell area in a phase image that is created based on a hologram obtained by in-line holographic microscope (IHM). A background value acquisition unit (242) obtains a background value from phase values at a plurality of positions outside the cell area. An intracellular phase value acquisition unit (243) averages a plurality of phase values on a sampling line set at a position close to the periphery of a cell, while avoiding a central portion in which the phase value may be lowered in the cell area, to obtain an intracellular phase value. A phase change amount calculation unit (244) obtains the difference between the intracellular phase value and the background value. A phase change amount determination unit (245) compares the value of the difference with thresholds in two levels to determine whether the cell is in an undifferentiated state or an undifferentiation deviant state. It is thereby possible to automatically make a correct determination while removing the influence of a theoretical measurement error by IHM.

A device for detecting particles in air; said device comprising: a flow channel configured to allow a flow of air comprising particles through the flow channel; a light source configured to illuminate the particles, such that an interference pattern is formed by interference between light being scattered by the particles and non-scattered light from the light source; an image sensor configured to detect incident light, detect the interference pattern, and to acquire a time-sequence of image frames, each image frame comprising a plurality of pixels, each pixel representing a detected intensity of light; and a frame processor configured to filter information in the time-sequence of image frames, wherein said filtering comprises:
identifying pixels of interest in the time-sequence of image frames, said pixels of interest picturing an interference pattern potentially representing a particle in the flow of air, and outputting said identified pixels of interest for performing digital holographic reconstruction.

The invention relates to a free-beam interferometric method for illuminating a sequence of sectional areas in the interior of the light-scattering object. The method makes it possible for the user to select a larger image field and/or a higher image resolution than previously possible with the occurrence of self-interference of the specimen light from a scattering specimen.

A method of reconstructing a three-dimensional (3-D) image on the basis of a diffraction grating includes extracting parallax images from a raw image of an object photographed by using a diffraction grating and reconstructing a 3-D image from the extracted parallax image array by using a virtual pinhole model.

Image persistence of the spatial light modulator is suppressed. A projection device (1) includes: an illumination optical system (12) that emits light; an information processing unit (20) that generates a hologram pattern based on an input image; a spatial light modulator (14) that forms the hologram pattern generated by the information processing unit and transmits light emitted by the illumination optical system; and a projection optical system (16) that projects an output of the spatial light modulator onto a projection surface and projects an output image, and the information processing unit generates the new hologram pattern obtained by shifting the hologram pattern in a predetermined direction for every predetermined frame.

A holographic microscope configured to observe a sample is provided. The holographic microscope includes a light source, a light splitting element, a polarizing element, a phase modulation element, a light combining element, and a photosensitive element. The light source is configured to provide an illumination beam. The illuminating beam is transmitted through the light splitting element to form a first light beam and a second light beam, and the sample is disposed on a transmission path of the first light beam. The polarizing element and the phase modulation element are disposed on the transmission path of the first light beam or the second light beam. The first light beam and the second light beam are transmitted to the light combining element to form an interference beam. The photosensitive element is disposed on a transmission path of the interference beam to receive the interference beam to generate an optical signal.

A method for multi-spectral scattering-matrix tomography includes a step of splitting an input light signal into an incident light signal and a reference light signal. The sample light signal is directed to a sample in either a reflection configuration or a transmission configuration such that an output light signal includes light scattered from or transmitted through the sample. The incident signal and the reference light signal are directed to a camera angled to allow for amplitude and phase to be calculated by off-axis holography. A total light signal is measured with a camera that is a coherent sum of the reference light signal and the output signal. The total light signal for each light frequency and each incident angle are collected as collected total light signal data. A computing device derives an image of the sample from a calculated reflection matrix or transmission matrix or both of them.

The illumination light condensing point P.sub.Q and the reference light condensing point P.sub.L are arranged as mirror images of each other with respect to the virtual plane VP, and each data of the object light O, being a reflected light of the spherical wave illumination light Q, and the inline spherical wave reference light L is recorded on each hologram. On the virtual plane VP, the reconstructed object light hologram h.sup.V for measurement is generated, and the spherical wave optical hologram s.sup.V representing a spherical wave light emitted from the reference light condensing point P.sub.L is analytically generated. The height distribution of the surface to be measured of the object 4 is obtained from the phase distribution obtained by dividing the reconstructed object light hologram h.sup.V by the spherical wave light hologram s.sup.V.