Abstract:
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.
Abstract:
An apparatus for producing a hologram of an object includes a light source that emits an incoherent electromagnetic wave toward the object, and a masking device configured to display a mask, receive the incoherent electromagnetic wave emitted toward the object, mask the received incoherent electromagnetic wave according to the displayed mask, and produce a masked electromagnetic wave. The apparatus also includes an image recording device configured to capture an image of the masked electromagnetic wave, and a processing device configured to convert the image of the masked electromagnetic wave into the hologram of the object. A method for producing a hologram of an object is also described.
Abstract:
A system is disclosed for recording a diffraction optical element providing a stereographic image to an observer includes a monochromatic light source having a characteristic wavelength providing a single source beam and a recording plate made from a material sensitive substantially to the characteristic wavelength. The system also includes at least first, second and third diffusers each having a characteristic wavelength differing from one another, a first beam split from the single source beam received from the monochromatic light source at the wavelength and at least one mirror reflecting a second split beam as a converging reference beam from the light source. The recording plate is exposed to the diffuse light beam separately passing through the first, second and third diffusers and received from the first beam and is exposed to the converging reference beam to form thereby the diffraction optical element.
Abstract:
The present invention is related to a method for performing digital holographic imaging (DHI), said DHI being characterized by the fact that images of a sample are obtained by applying numerical means to reconstruct holograms of the sample. In the method of the invention, the sample is in a medium with controlled properties that influence the behaviour of the sample, and/or that influence the process of hologram formation. The information content of one hologram, or of a plurality of holograms, recorded with the sample in one medium, or in a plurality of medium, is used to reconstruct one image of the sample, or a plurality of images of the sample, that describe quantitatively one property of the sample, or a plurality of properties of the sample. The present invention is also related to an apparatus with which to perform said method.
Abstract:
An encoded hologram that produces a first image and a second image pursuant to playback illumination, wherein the first image is resolvable by human vision while the second image is not resolvable by human vision when the playback illumination comprises non-coherent broad band illumination, and wherein the second image is machine readable when the hologram is illuminated with playback illumination that is based on the original reference beam.
Abstract:
A holographic method of the type implementing a conoscopic system including a birefrigent crystal inserted between two polarizers and a photosensitive element, wherein the method includes a step consisting in inserting one-dimensional optical means on the path of the light rays such that the conoscopic system only collects light that is parallel or quasi-parallel to a plane including the axis of the conoscopic system. The invention also provides apparatus for implementing the method.
Abstract:
A holographic recording medium is treated to eliminate side lobes. The method involves exposing opposed surfaces of the medium with filtered incoherent light either before or after a holographic exposure with coherent light. The incoherent exposure produces controlled desensitization of the medium, resulting in a sensitivity profile which increases continuously to a maximum near the center of the layer. A hologram recorded in the layer has a refractive index modulation which is high in the center of the layer and which decreases toward the surfaces of the layer.
Abstract:
A device for imaging layers of the interior of a three-dimensional object. The object is irradiated from a large number of radiation source positions which are distributed in one plane from this, a coded image of the object which coded image consists of separate perspective images is produced. The coded image is illuminated and imaged by means of an imaging matrix whose imaging elements are distributed in the matrix plane according to the flat distribution of the radiation source positions. Layer images of the object are formed on a photosensitive element by the superposition of the perspective images. For forming different layer images of the object, the imaging elements are positioned in different distributions of changed scale with respect to the distribution of the radiation source positions.
Abstract:
A self-supporting uniformly redundant array pattern for coded aperture imaging. The present invention utilizes holes which are an integer times smaller in each direction than holes in conventional URA patterns. A balance correlation function is generated where holes are represented by 1's, nonholes are represented by -1's, and supporting area is represented by 0's. The self-supporting array can be used for low energy applications where substrates would greatly reduce throughput. The balance correlation response function for the self-supporting array pattern provides an accurate representation of the source of nonfocusable radiation.
Abstract:
The present invention pertains to a mosaic of coded aperture arrays which is capable of imaging off-axis sources with minimum detector size. Mosaics of the basic array pattern create a circular on periodic correlation of the object on a section of the picture plane. This section consists of elements of the central basic pattern as well as elements from neighboring patterns and is a cyclic version of the basic pattern. Since all object points contribute a complete cyclic version of the basic pattern, a section of the picture, which is the size of the basic aperture pattern, contains all the information necessary to image the object with no artifacts.