Abstract: A method of recording holograms includes: generating a first signal-beam from a signal-beam source and a first reference beam from a reference-beam source; recording a first hologram in a holographic medium from an interference between the first signal beam and the first reference beam; shifting the reference-beam source after the act of recording the first hologram; generating a second signal beam from the signal-beam source and a second reference beam from the reference-beam source after the act of shifting the reference-beam source following the recording of the first hologram; and recording a second hologram in the holographic medium from an interference between the second signal beam and the second reference beam.

Abstract: Disclosed are holographic storage systems and lenses for holographic storage systems. The lens units can be of a two-component design. The lenses can be used to both record to photorefractive storage media and to read from photorefractive storage media.

Abstract: Associative retrieval techniques of this invention allow a holographic recording device to simultaneously query a plurality of storage locations for the presence of a given data pattern. The techniques use a known pattern common to one or more storage locations to simultaneously verify the success of one or more write operations.

Abstract: Blue-sensitized holographic media suitable for recording with a blue laser is disclosed. The blue-sensitized holographic media provides greater dynamic range and a higher sensitivity than a green-sensitized holographic media, thereby providing more rapid hologram writing times.

Abstract: Holographic articles having self-sealing properties such as moisture resistance and environmental durability are disclosed. The holographic articles are formed by the reaction of a composition containing an excess amount (i.e. non-stoichiometric amount) of polyisocyanates to polyols. The holographic recording articles exhibit high optical clarity and low scattering.

Abstract: A rapid mass production of the high performance holographic recording articles including the process and composition are described. To prepare a high performance holographic recording article based on two-component urethane matrix system, for example, polyols and all the additives must be virtually free of moisture contents. Deaeration must be carried out, once isocyanate and polyols including catalysts and all other ingredients are mixed together, to eliminate all entrapped air that is introduced into the mixture during mixing. The deaeration takes time, and the urethane reaction must not be allowed to take place until all air bubbles are evacuated from the isocyanate-polyols mixture. The rapid mass production of this invention overcomes such process limitations and results in a high-volume production of the high performance holographic recording articles.

Abstract: A method of writing holograms includes: numbering sections in sequence, where each section has a spatial projection onto a holographic medium; and writing at least one hologram in each of the sections in sequence. Writing in two sections with adjacent spatial projections provides a substantially uniform exposure level for a sequentially subsequent section with a spatial projection that overlaps the two sections.

Abstract: A method and system of recording successive holograms in a recording medium including a reflective substrate layer, a polarization shifting layer, and a photorecording medium layer is presented. A reference beam and an object beam are propagated at a first direction to a first area of the photorecording medium layer, where the reference beam and object beam have a same first polarization and interfere to produce a first interference grating. The reference beam and object beam are reflected with the reflective substrate layer to be incident the photorecording medium at a second direction, where the reference beam polarization and object beam polarization are altered with the polarization shifting layer to have a same second polarization. The reflected reference beam and object beam interfere to produce second interference grating, with the first polarization and second polarization being different.

Abstract: The present invention provides a solution to the needs described above through a system and method for holographic storage. The system comprises a laser light source, a first beam splitter for splitting a light beam into an object and reference beam, an elliptical reflector with a first and second focal point, a reflector rotatable about a first axis and a second axis, a pattern encoder, and a holographic storage medium. The reflector is located at the first focal point of the elliptical mirror, and the holographic storage medium is located at the second focal point of the elliptical mirror.

Abstract: Holography in which an array of overlapping holograms is recorded or reconstructed in a recording medium, holograms being produced by interference of a reference beam and a signal beam, in which the reference beam is a phase beam which consists essentially of a multitude of rays of varying angle of incidence and non-uniform phase, in which the process comprises changing the orientation of the phase beam for recording or reconstructing different holograms, wherein phase beam orientation is changed relative to the medium while maintaining the medium stationary in order to enable recording or reconstruction of individual holograms at a given location of the medium.

Abstract: Disclosed is a holographic card for storing data in holographic format in accordance with the present invention includes a holographic layer for containing holographic information and a transparent protective layer overlaying the holographic layer. The holographic layer includes at least a first data section with machine readable holographic data. The card also includes a second data section containing either or both presentation or security data. The second data section is preferably included in the holographic layer, but can also be separate therefrom, particularly when non-holographic data is contained therein.

Abstract: Described are holographic storage mediums and method of making holographic storage mediums. The holographic storage mediums may have write components that bind to the matrix to form a pattern in the media. The holographic storage mediums may also be rewriteable.

Abstract: A holographic storage medium, a method of manufacturing the holographic storage medium and a holographic storage device incorporating the storage medium. In one embodiment, the holographic storage medium includes: (1) first and second spaced-apart substrates, the first substrate being plastic and (2) a photopolymer core located between said first and second substrates and having a coefficient of thermal expansion such that said first and second substrates and said photopolymer core cooperate to respond substantially isotropically to a change in temperature.

Abstract: Holographic media having a photoactive ingredient, such as a photoactive dye, that produces reactive species that directly or indirectly react with oxygen and other inhibitors present in the media to protect the media before recording are disclosed. Methods for holographic media protection and inhibitor and oxygen removal are also disclosed.

Abstract: Disclosed are holographic storage systems and lenses for holographic storage systems. The lens units can be of a two-component design. The lenses can be used to both record to photorefractive storage media and to read from photorefractive storage media.

Abstract: Disclosed are methods of producing obliquity corrected light beams, and holographic recording and retrieval systems that utilize a obliquity corrected reference beam. The obliquity correction is accomplished using off-center lenses.

Abstract: The optical article of the invention, e.g., holographic recording medium or polymeric waveguide, is formed by mixing a matrix precursor and a photoactive monomer, and curing the mixture to form the matrix in situ. The reaction by which the matrix precursor is polymerized during the cure is independent from the reaction by which the photoactive monomer is polymerized during writing of data. In addition, the matrix polymer and the polymer resulting from polymerization of the photoactive monomer are compatible with each other. Use of a matrix precursor and photoactive monomer that polymerize by independent reactions substantially prevents cross-reaction between the photoactive monomer and the matrix precursor during the cure and inhibition of subsequent monomer polymerization. Use of a matrix precursor and photoactive monomer that result in compatible polymers substantially avoids phase separation. And in situ formation allows fabrication of articles with desirable thicknesses.