摘要:
A polymerizable media, including holographic recording media, and methods of use of the same. The media comprises at least one monomer or oligomer which undergoes polymerization to form a polymer; a compound, which absorbs actinic radiation of a first wavelength and forms a sensitizer which absorbs actinic radiation of a second wavelength; and an initiator, which, in combination with the sensitizer, initiates polymerization of the at least one monomer or oligomer when said sensitizer is exposed to actinic radiation of the second wavelength.
摘要:
A method of recording a plurality of holographic images in a holographic media, comprising recording a sequence of multiplexed holograms in a selected storage location in the holographic recording media, each hologram having a respective interbeam angle. The interbeam angle increases for each subsequently recorded hologram to compensate for a variable shrinkage of the holographic media during recording. The multiplexed holograms recorded at the selected storage location are partially or fully overlapped. During reading the recorded holograms, a reference beam is directed at a selected storage location in the holographic recording media at a sequence of incidence angles, each incidence angle being adjusted by a respective adjustment angle. The adjustment angles can be substantially equal.
摘要:
An apparatus for image acquisition of topological features of the surface of skin. The apparatus comprises a waveguide, having an entrance edge and top and bottom surfaces; a light source, configured to direct a light beam at the entrance edge of the waveguide; a skin contact layer, disposed at or near the top surface of the waveguides; a holographic optical element (HOE), disposed at the top or at the bottom surfaces of the waveguide, configured to diffract the light beam incident from the light source to the skin contact layer; a sensor array, configured to detect light reflected from the surface of skin in contact with skin contact layer; and means for compensating for changes in the Bragg matching condition of the HOE due to temperature.
摘要:
Holographic data storage systems are fixed after exposure during which data in the form of holograms are stored at locations in the medium (4). Sufficient fixing energy in the form of light or other electromagnetic and thermal radiation is applied to the media (4) either by flooding the media, or to specific locations where the medium has been written. The energy is sufficient to expose the recorded medium (4) to prevent recording in the unused dynamic range thereof. Such recording can be a spurious recording made during readout or from spurious sources of light incident on the media. In one embodiment, the reference beam (108) produced in the course of holographic recording is redirected to locations on the media (4) which have already been recorded. The redirected beam post exposes the media to fix these locations against spurious recording. The integrity of the holographic data storage systems and the robustness thereof is improved by fixing methods and apparatus incorporating the invention.
摘要:
A holographic optical filter that includes an optical recording medium for storing several multiplexed reflection holograms that are formed by successive interference between two or more collimated object beams with a common collimated reference beam. The object beams are incident to the recording material at a series of angles chosen to provide reflection efficiency over the desired filed of view at the specified wavelength.
摘要:
An apparatus and method that produces recording media using at least two platens. A first platen is movable relative to a second platen, and each platen has respective first and second support surfaces onto which substrates are placed, the first and second substrates each having inner and outer longitudinal surfaces. A centering device aligns the respective substrates relative to a one or more reference positions, a positioning system provides a degree of parallelism between the outer longitudinal surfaces of each of the substrates and produces a desired gap between the inner longitudinal surfaces of the substrates, and a dispensing unit which emits a liquid medium within the gap between inner longitudinal surfaces of the substrates.
摘要:
Disclosed is a holographic recording medium. The novel holographic recording mediums disclosed herein comprises: a) at least one polyfunctional epoxide monomer or oligomer which undergoes acid initiated cationic polymerization. Each epoxide in the monomer or oligomer is linked by group comprising a siloxane to a silicon atom and each monomer or oligomer has an epoxy equivalent weight of greater than about 300 grams/mole epoxide; b) a binder which is capable of supporting cationic polymerization; c) an acid generator capable of producing an acid upon exposure to actinic radiation; and optionally d) a sensitizer.
摘要:
An apparatus for image acquisition of topological features of the surface of skin. The apparatus comprises a waveguide, having an entrance edge and top and bottom surfaces; a light source, configured to direct a light beam at the entrance edge of the waveguide; a skin contact layer, disposed at or near the top surface of the waveguides; a holographic optical element (HOE), disposed at the top or at the bottom surfaces of the waveguide, configured to diffract the light beam incident from the light source to the skin contact layer; a sensor array, configured to detect light reflected from the surface of skin in contact with skin contact layer; and means for compensating for changes in the Bragg matching condition of the HOE due to temperature.
摘要:
Photosensitizing dyes are often used in conjunction with a photoacid generator in photopolymerizable materials and in holographic recording media. Typical dyes for these materials are used in the region of the visible spectrum for wavelengths greater than about 450 run. The present invention discloses a number of new 1,4-alkynyl substituted napthalene photosensitizing dyes that have suitably low extinction coefficients coupled with good sensitizing properties for use in such materials at wavelengths in the visible spectrum region of about 400 nm.
摘要:
An apparatus for writing and reading holograms, comprising a spatial light modulator (SLM) operable in phase mode, having a plurality of pixels for generating an object beam that overlaps with a reference beam; a holographic recording medium (HRM) in the path of the object beam; and a first lens element disposed in the path of the object beam between the SLM and the HRM; wherein the HRM is disposed at or near the Fourier transform plane of the first lens element.