394 results about "Holographic data storage" patented technology

The invention provides methods for enterprise business visibility that transform any of marketing, e-commerce and transactional from a plurality of legacy and other databases into resource description framework (RDF) syntax. This information can be time-stamped (e.g., with expiration dates) and stored in a central data store. Answers to queries are discerned by applying genetic algorithm-based search techniques to the holographic store, with the confidence levels of those answers is based in part, for example, on the time-stamps of the triples.

A holographic storage apparatus for recording data in a holographic medium includes at least one light source for generating a reference beam and a signal beam. The reference beam is preferably a phase beam of unchanging phase content. The apparatus also includes a holographic medium placed in a path of the reference beam and a path of the signal beam. The holographic medium has a first face and both the reference beam and the signal beam enter the holographic medium through the first face. The holographic medium also includes a data reflective surface. The reference beam and the signal beam interfere in the holographic medium to create a hologram only after at least one of the reference beam and the signal beam have reflected off of the data reflective surface.

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.

According to one aspect and example, a method for recording holographic media and / or holographic master data masks includes recording at least a first hologram or information layer with a first holographic medium (e.g., a “submaster”) and recording at least a second information layer with a second holographic medium (e.g., a second “submaster”). The first information layer and the second information layer from the first and second holographic media are then sequentially reconstructed and stored with a single holographic master medium (e.g., a “master”). The holographic master may then be used to record the stored first and second information layers into additional holographic media, for example, into HROM devices or the like.

Holographic data storage devices are presented. The holographic data storage device includes an optically transparent substrate, wherein the optically transparent substrate includes a photochemically active dye and a heat generating chromophore. Methods for making holographic data storage device are also presented.

Systems and methods for constructing concatenated codes for data storage channels, such as holographic storage channels, are provided. The concatenated codes include an outer BCH code and an inner iteratively decodable code, such as an LDPC code or turbo code. The correction power and coding rate of one or both of the codes may be programmable based on the channel characteristics and the desired SNR coding gain. The correction power and / or coding rate of the inner and / or outer code may also be dynamically adjusted in real-time to compensate for time-varying error conditions on the channel.

A holographic memory device for use in a personal electronic device is disclosed. The device contains a holographic data storage media adapted to store a data pattern associated with a data beam. The device has capability for reading and writing to the holographic data storage media. The device contains a personal electronics device interface for receiving data from and providing data to a host personal electronics device. The device reads and writes data to the holographic data storage media in response to requests received via the personal electronics device interface.

A method of determining coordinates for a storage medium includes: determining diffraction data from a plurality of diffraction patterns corresponding to diffractive markers of the medium; and combining the diffraction data to determine composite coordinates for the medium. The composite coordinates may include three translational coordinates and three rotational coordinates. The act of determining diffraction data may include shining a plurality of beams on a selection of the diffractive markers, and measuring the corresponding diffraction patterns in one or more photodetectors to determine the diffraction data. In this latter case the photodetectors may be segmented. The act of combining the diffraction data to determine composite coordinates may include solving a matrix system that couples the diffraction data and the composite coordinates. Each diffractive marker may include a pit. The storage medium may include a holographic storage medium.

Methods for holographic data storage are disclosed. The method includes providing an optically transparent substrate comprising a photochemically active dye and irradiating the optically transparent substrate with a holographic interference pattern and a photochromic conversion control illumination. The pattern has a first wavelength and an intensity both sufficient to convert, in the presence of the photochromic conversion control beam, within a volume element of the substrate, at least some of the photochemically active dye into a photo-product, and producing within the irradiated volume element concentration variations of the photo-product corresponding to the holographic interference pattern thereby producing an optically readable datum corresponding to the volume element. The photochromic conversion control illumination has a second wavelength and an intensity to control the photochromic conversion amplitude in the volume element.

A description is provided of an optical information recording and reproducing apparatus. The apparatus comprises: a holographic memory made of a photorefractive crystalline material; a support portion for detachably supporting the memory; a reference beam supplying portion for supplying a coherent reference beam of a first wavelength incident on the memory; a signal beam generating portion for supplying a coherent signal beam of the first wavelength, which is modulated in accordance with image data, incident on the memory, intersecting therein the signal beam with the reference beam, and generating a three-dimensional interference pattern of the beams; a detecting portion for detecting a diffracted light from a refractive index grating of the interference pattern in the memory, due to irradiation of the reference beam; and a medium position adjusting portion for moving a position of the support portion in accordance with a signal corresponding to positioning images from the detection portion. The memory includes a nonvolatile refractive index grating corresponding to a three-dimensional interference pattern of a coherent reference beam and a coherent signal beam, the coherent signal beam being modulated in accordance with positioning images.

Methods for storing holographic data are presented. The method includes providing an optically transparent substrate comprising a thermally active photochemically active polymer composition, the polymer composition including a photochemically active dye and a heat generating chromophore, thermally activating at least a part of a volume element of the optically transparent substrate to increase a quantum efficiency of photochemical conversion of the photochemically active dye into a photo-product, within the at least a part of the volume element and converting at least some of the photochemically active dye to a photo-product, and producing concentration variations of the photo-product within the volume element of the optically transparent substrate, thereby producing an optically readable datum corresponding to the volume element.

The present invention provides a hologram recording medium which can attain high refractive index change, flexibility, high sensitivity, low scattering, environment resistance, durability, low dimension change (low shrinkage) and high multiplicity in holographic memory record using a blue laser. A hologram recording medium (11) comprising at least a hologram recording material layer, wherein the hologram recording material layer (21) comprises at least a metal oxide and a photopolymerizable compound; and said hologram recording medium has a light transmittance of 50% or more at a wavelength of 405 nm, or a light reflectance of 25% or more at a wavelength of 405 nm.

The present invention provides a hologram recording medium wherein, in holographic memory recording using a blue laser as well as a green laser, a fall in light transmittance is very small even after recording. A hologram recording medium comprising at least a hologram recording material layer, wherein the hologram recording material layer (21) comprises at least fine particles of a metal compound, and a photopolymerizable compound; and the recording sensitivity of said recording medium (11) to a laser light having a wavelength of 405±5 nm is 0.05 cm / mJ or more and 1.20 cm / mJ or less.

The present invention provides a hologram recording material which is suitable for volume hologram record and attains high refractive index change, flexibility, high sensitivity, low scattering, environment resistance, durability, low shrinkage and high multiplicity in holographic memory record using not only a green laser but also a blue laser; a process for producing the same; and a hologram recording medium having the hologram recording material. A hologram recording material comprising: a metal oxide comprising Si and at least one selected from the group consisting of Ta and Zr, as metals, wherein a complexing ligand is coordinated to Ta and / or Zr; and a photopolymerizable compound. The complexing ligand is preferably selected from the group consisting of β-dicarbonyl compounds, polyhydroxylated ligands, and α- or β-hydroxy acids. A hologram recording medium (11) comprising the hologram recording material layer (21).

The present invention provides a hologram recording medium which is suitable for volume hologram record and can attain high refractive index change, flexibility, high sensitivity, low scattering, environment resistance, durability, low dimensional change (low shrinkage) and high multiplicity in holographic memory record using not only a green laser but also a blue laser. A hologram recording medium (11) comprising at least a hologram recording layer (21), wherein the hologram recording layer contains a metal oxide matrix comprising metal oxide fine particles, and a photopolymerizable compound; the metal oxide fine particles comprise metal oxide fine particles containing Ti as a metallic element; and at the time of subjecting the hologram recording layer before exposure to light to an extraction operation in n-butyl alcohol having a mass 100 times the mass (W) of said recording layer, thereby yielding a sol solution; filtrating the sol solution to obtain a filtrated sol solution; and measuring particle diameter distribution of sol particles in the filtrated sol solution by a dynamic light scattering method; and obtaining an average particle diameter thereof, the average particle diameter of the sol particles is in the range of 5 nm or more and 50 nm or less.

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.

The object of the invention is a high data density holographic data storage method. The holograms are written into the volumetric data storage layer or layers, and during the writing process the accurate places of holograms in the data carrier structure are determined by the intersection domain of the object and reference beam or beams, and during the reading process the selection of holograms simultaneously illuminated by the reference beam or beams, the read-out of the addressed hologram, and the suppressing of un-addressed holograms are carried out by a spatial filter located confocally with the addressed hologram and / or by satisfying the Bragg condition. The optical arrangement for recording and reading out holograms has three dedicated planes in confocal arrangements, where the addressed hologram is in the middle dedicated plane in the storage material, and in the two outer dedicated planes there are spatial filters. The optical arrangement is a 12f optical System consisting of three pairs of objectives.

The present invention provides a hologram recording medium wherein high refractive index change, flexibility, low scattering, environment resistance, durability, low dimensional change (low shrinkage), and high multiplicity are attained in holographic memory recording using a blue laser as well as a green laser. A hologram recording medium comprising at least a hologram recording layer, wherein the hologram recording layer (21) contains at least an organometallic compound which contains a metal atom, an organic group, and an oxygen atom, and has a direct bond between the metal atom and a carbon atom in the organic group (a metal-carbon bond), and a bond between the metal atoms through the oxygen atom (a metal-oxygen-metal bond) and a photopolymerizable compound; and the hologram recording layer (21) contains the metal atoms in an amount of 3.0% by mass or more and 20% by mass or less with respect to the hologram recording layer.

According to one aspect a method for manufacturing a holographic storage medium includes providing one or more data masks with data to be recorded, illuminating the one or more data masks onto the medium with a plane wave object beam from a laser light source operating at a record wavelength, propagating a reference beam at an incident angle to the medium to record the one or more data masks on the medium, and altering the incident angle of the reference beam for each of the one or more data masks, wherein each of the one or more data masks recorded on said medium can be read bit by bit using a laser light source operating in a readout range of wavelengths different from the record wavelength.

The present invention relates to a reproduction device of a holographic memory capable of precisely reproducing multi-value phase information without being influenced by noise. This holographic memory reproduction device comprises: a hologram diffraction ray generation unit which irradiates a first reference ray to the holographic memory and generates a diffraction ray of the first hologram; a hologram generation unit which changes the phase of a second reference ray which may interfere with the diffraction ray of the first hologram and generates a second hologram from the diffraction ray of the first hologram and the second reference ray to which the phase has been changed; a detection unit which detects the intensity distribution of the second hologram; and a processing unit which demodulates the phase modulation signal or the space quadrature amplitude modulation signal on the basis of the intensity distribution.

A data input method is applied to a holographic digital data storage system in which sequential binary input data bits are arranged in an interleaved manner among pages. A first data bit is arranged in a specific position of a predetermined page, a second data bit is arranged in a specific position having similar beam intensity with that of the first data bit. Using this method, the holographic digital data storage system can be less affected by the adverse effect of spatial beam intensity variations and makes the entire data interleaved automatically to obtain more stable output data.

A portable data storage cartridge comprising a housing, a first information storage medium removeably disposed within the housing, a holographic data storage medium disposed within the housing, wherein the housing is formed to include an aperture, and wherein the holographic data storage medium is disposed adjacent the aperture.

The invention belongs to the field of high-density optical storage, and relates to a method for preparing a photopolymer holographic storage optical disk. The invention provides a photopolymer holographic storage material simultaneously, which is a multi-component mixing material in which a low-refractive index amine cured epoxy system is taken as film-forming resin and a high-refractive index alkenyl monomer is taken as an information recording component. The invention provides a method for preparing a size-controlled photopolymer holographic storage optical disk die based on a material formula. Simultaneously, the invention provides a method for preparing a photopolymer holographic storage optical disk, which is simple to operate, is low in cost and can be implemented at room temperature. In the optical disk prepared by the method, the thickness of the holographic storage material is between 100 and 500 micrometers; and various lasers which are matched with the wavelengths can be selected as information recording light sources within the wide-waveband range of between 400 and 600 nanometers by selecting different photosensitizers, and the mass storage of information is realized by angle and wavelength multiplexing.

The present invention provides a hologram recording material which is suitable for volume hologram record and attains high refractive index change, flexibility, high sensitivity, low scattering, environment resistance, durability, low shrinkage and high multiplicity in holographic memory record using not only a green laser but also a blue laser; a process for producing the same; and a hologram recording medium having the hologram recording material. A hologram recording material comprising: a metal oxide containing at least Si and Zr as metals wherein a β-dicarbonyl compound is coordinated to Zr; and a photopolymerizable compound, wherein a mole ratio of the β-dicarbonyl compound to the Zr atom (β-dicarbonyl compound / Zr ratio) is 2 / 1 or more and 3 / 1 or less, and a mole ratio of the Si atom to the Zr atom (Si / Zr ratio) is more than 1 / 1 and 1.15 / 1 or less in the metal oxide. A hologram recording medium (11) comprising the hologram recording material layer (21).

The present invention provides a method and system for increasing the holographic storage capacity of a holographic recording medium using an irradiance-tailoring (e.g., optical) element by changing the irradiance profile of the modulated object beam (e.g., by imparting motion to an irradiance-tailoring element and / or the holographic recording medium and / or by reconfiguring (e.g., periodically) the phase profile of a stationary irradiance-tailoring (e.g., optical) element) to minimize the effects of fixed-pattern noise buildup from occurring in the holographic recording medium.

A hologram recording medium can record an interference pattern to a volume holographic memory at high density. Therefore, the hologram recording medium is made of a photo refractive crystal of a uniaxial crystal having a shape of parallel flat plates, and has a plurality of areas of a refractive index grating corresponding to one portion of a three-dimensional light interference pattern of a coherent signal light beam and coherent reference light of a first wavelength modulated in accordance with information data, wherein the areas of the refractive index grating respectively have a spatially independent columnar shape and are juxtaposed in parallel with each other, and lattice vectors of the refractive index grating in the adjacent areas of the refractive index grating exist in directions different from each other.

A spatial light modulator (SLM) having a phase mask that is provided as an internal component thereof. The phase mask can be provided as a multilevel surface of relatively higher index of refraction material on an inner surface of a transmissive cover window or as a separate transmissive window between the cover window and the pixels of the SLM. If the phase mask is to be used with a liquid crystal SLM, then it may be desirable to planarize the surface of the cover window contacting the liquid crystal by providing a layer of relatively lower index of refraction material adjacent the multilevel surface. The phase mask can also be provided on the transmissive cover window by patterned ion deposition, exposing patterned light to a photopolymeric material, or in some other suitable fashion. Arranging for the pixel electrodes to be at one of multiple levels rather than lying in an exactly planar relationship can also effectively create the phase mask.

A description is provided of an optical information recording and reproducing apparatus. The apparatus comprises: a holographic memory made of a photorefractive crystalline material; a support portion for detachably supporting the memory; a reference beam supplying portion for supplying a coherent reference beam of a first wavelength incident on the memory; a signal beam generating portion for supplying a coherent signal beam of the first wavelength, which is modulated in accordance with image data, incident on the memory, intersecting therein the signal beam with the reference beam, and generating a three-dimensional interference pattern of the beams; a detecting portion for detecting a diffracted light from a refractive index grating of the interference pattern in the memory, due to irradiation of the reference beam; and a medium position adjusting portion for moving a position of the support portion in accordance with a signal corresponding to positioning images from the detection portion. The memory includes a nonvolatile refractive index grating corresponding to a three-dimensional interference pattern of a coherent reference beam and a coherent signal beam, the coherent signal beam being modulated in accordance with positioning images.