416 results about "Holographic 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.

Holographic storage media including a substrate and a dye material capable of undergoing a photo-induced change are disclosed. Data may be written into the holographic storage media using light of one wavelength and read using light of a different wavelength.

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.

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.

The present invention relates to embodiments of a process for subjecting a holographic storage medium to illuminative treatment to: (1) enhance or optimize recording of holographic data; (2) enhance or optimize reading of recorded holographic data; and / or (3) erase recorded holographic data. The present invention also relates to embodiments of a system comprising: (a) an illuminative treatment beam; (b) means for reducing the coherence of the beam and (c) means for transmitting the reduced coherence beam to cause illuminative treatment of: (1) an unrecorded portion of a holographic storage medium to provide pre-cured portions having increased ability to stably record holographic data; (2) a recorded portion of a holographic storage medium to provide a post-cured portion having reduced residual sensitivity; and / or (3) a recorded portion of a holographic storage medium having holographic data to provide an erased portion wherein at least some of the recorded holographic data is erased.

Methods and systems are provided for obtaining a phase conjugate reconstruction beam for use in retrieving holographic information from a holographic storage medium. These methods and systems include generating a coherent light beam that is a reproduction of the reference beam used in storing the holographic information in the storage medium. This coherent light beam is then directed through the holographic storage medium at the same angle and location of the reference beam during recording of the hologram. The directed coherent beam is then reflected back through the storage medium so that the reflected coherent light beam provides a phase conjugate of the reference beam and passes through the storage medium at the same angle and location that the reference beam passed through the storage medium during recordation of the hologram.

According to one aspect and example, a holographic recording system includes a light source, an object for modulating an object beam from the light source, and a relay system adapted to magnify (positive or negative) the modulated beam (e.g., an image of the object) to an output image. The object may include an SLM operable to modulate the object beam with an information layer comprising a plurality of data pages. The output image is directed to the holographic storage medium, where a reference beam is also directed, to record the resulting interference pattern. Additionally, the relay system converges the output image to an output Fourier plane, which may be disposed within the holographic storage medium. A filter may be placed at an intermediate Fourier plane located prior to the output Fourier plane, and a phase mask may be placed at the position of the output image.

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.

According to one aspect, methods and systems for recording and reading holographic storage media are provided. In one aspect, a method includes illuminating a data mask with a beam and recording a resulting modulated beam in a holographic storage medium, wherein the data mask includes an information layer that is divided into multiple data pages, and propagating a reference beam to the holographic storage medium to record the multiple data pages of the data mask in a parallel fashion on the holographic storage medium.

A method for holographic storage data recovery in a holographic storage system is presented. One exemplary method includes detecting a stored image at a detector such that the image is oversampled. A relationship is determined between a location of the detected image and a location of the source image. Pixel information associated with the source image may be obtained from the detected image based on a fractional delay filter. In one example, the image may be oversampled by magnifying the detected image at the detector and / or having a detector with pixel sizes and spacing less than the image pixel size. Further, coefficients of the fractional delay filter may be determined, at least in part, on magnification and shift information of the image based on known registration marks.

The present invention relates to embodiments of a process for subjecting a holographic storage medium to illuminative treatment to: (1) enhance or optimize recording of holographic data; (2) enhance or optimize reading of recorded holographic data; and / or (3) erase recorded holographic data. The present invention also relates to embodiments of a system comprising: (a) an illuminative treatment beam; (b) means for reducing the coherence of the beam and (c) means for transmitting the reduced coherence beam to cause illuminative treatment of: (1) an unrecorded portion of a holographic storage medium to provide pre-cured portions having increased ability to stably record holographic data; (2) a recorded portion of a holographic storage medium to provide a post-cured portion having reduced residual sensitivity; and / or (3) a recorded portion of a holographic storage medium having holographic data to provide an erased portion wherein at least some of the recorded holographic data is erased.

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.

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 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.

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.

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.

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 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 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.

The invention discloses a preparation method of sliver / titanium dioxide film materials used for blue-ray holographic storage, and belongs to the field of optical information storage material preparation. The preparation method comprises the following steps: preparing a titanium dioxide film, tannin acid solution of which the pH (Potential Of Hydrogen) value is 8.5, silver nitrate solution and a titanium dioxide film attached with tannin acid, obtaining a sliver / titanium dioxide film with a water bath heating method, and carrying out a spectrum test and holographic storage on the sliver / titanium dioxide film. According to the preparation method, the tannin acid is used as reductant to obtain the sliver / titanium dioxide film materials. Through the detection of an absorption spectrum, compared with a traditional preparation method, the preparation method has the advantages of strong adsorption at a position of short wave and narrow absorption peak and is suitable for the holographic storage of short-wave light. The observation of a kinetic curve of holographic grating growth proves that the efficient and quick holographic storage of short-wavelength blue ray can be realized by the sliver / titanium dioxide film materials prepared with the preparation method.

An apparatus, system, and method are disclosed for calibrating a holographic storage device. A read channel reads a factory-stored hologram from a holographic media. A calculation module calculates a read difference between the read factory-stored hologram and a first holographic pattern that digitally describes the factory-stored hologram. In one embodiment, a calibration module calibrates the read channel with the read difference.

A holographic data storage (HDS) system and method are provided. Generally, the system includes: a light source for generating a coherent light; beam-forming optics for forming the light into collimated object and reference beams; holographic storage medium; a spatial light modulator (SLM) located in a path of the object beam from the beam-forming optics to the storage medium, the SLM having a number of pixels for encoding data to be stored in the medium into the object beam. Preferably, the SLM can modulate both the amplitude and phase of light from every pixel on the SLM. More preferably, the SLM is also located in a path of the reference beam to the storage medium to modulate the phase of the light to store multiple holographic pages of data in the same physical volume of medium through phase multiplexing. Other embodiments are also described.

The present invention provides a method for storing holographic data comprising providing a holographic storage medium comprising an optically transparent substrate including a photochemically active dye having at least two nitrone groups; and irradiating the optically transparent substrate with a holographic interference pattern, wherein the pattern has a first wavelength and an intensity both sufficient to convert, 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 a first optically readable datum corresponding to the volume element.

A holographic medium is formed of an optical waveguide including at least one core layer positioned between at least one portion of a material having a lower refractive index, a diffraction grating layer formed at a boundary between the core layer and the material of lower refractive index or in the core layer, and a storage layer outside the optical waveguide. Upon storing information in the storage layer a reference beam and an object are input into the optical waveguide and in retrieving stored information the reference beam is emitted to an end face of the core layer and transmitted through the core layer to be transformed into a diffracted beam in a diffraction grating layer that is emitted outside the core layer and transmitted through the storage layer, where the object beam is retrieved as a retrieved beam.