Abstract: A tuning methods of an External Cavity Laser Diode (ECLD), comprises steps of: (1) providing a laser light to a grating so as to tilt the grating to an optical axis of a collimated laser light, (2) adjusting the orientation of the grating relative to the collimated laser light, (3) monitoring singleness of longitudinal mode and optical power of a light emitted from the grating, (4) calculating an orientation of the grating to exhibit intended optical power at which the singleness of longitudinal mode shows at least predetermined value, (5) adjusting the grating orientation or the optical axis of the collimated laser light to the calculated grating orientation.

Abstract: An optical pickup for recording a hologram by using an angle multiplexing method. An optical beam is separated into two beams, a signal beam and a reference beam having different convergence/divergence degrees, by using an optical component such as a diffraction lens. The signal and reference beams are made incident upon the same objective, and the optical component or the objective lens is moved in a direction perpendicular to an optical axis, to thereby realize angle multiplex recording. If an optical information recording medium is inclined, the optical component or the objective lens is moved along the direction along which the optical information recording medium moved to change an angle of the reference beam incident upon the optical information recording medium and compensate for degradation of a reproduction signal.

Abstract: In holographic recording, it is important to form stably an interference fringe between a reference beam and a signal beam in a holographic storage medium. To suppress factors degrading stability of the interference fringe, such as fluctuation of atmospheric air, position displacement of optical components and the like during propagation of the reference and signal beams, an optical pickup and an optical information recording/reproducing apparatus adopt an optical system structure providing a higher proportion of optical components shared by the reference and signal beams optical path than conventional optical system structure. To increase the proportion of shared optical components, the signal beam and the reference beam pass through the PBS prism as parallel beams and a concave lens is placed on a reference beam path just before the objective lens.

Abstract: The present invention relates to a system, as well as articles and holographic recording medium comprising the system, where the system comprises: a polymerizable component comprising at least one photoactive polymerizable material; and a photoinitiator component comprising at least one photoinitiator for causing the polymerizable component to polymerize to thereby form a plurality of holographic gratings when activated by exposure to a photoinitiating light source; wherein when a portion of the polymerizable component has been polymerized to form at least one holographic grating, the unpolymerized portion of the polymerizable component is resistant to further polymerization when not exposed to the photoinitiating light source. The present invention also provides methods for forming at least one holographic grating in a holographic recording medium having such a photopolymerizable system.

Abstract: A tuning methods of an External Cavity Laser Diode (ECLD), comprises steps of: (1) providing a laser light to a grating so as to tilt the grating to an optical axis of a collimated laser light, (2) adjusting the orientation of the grating relative to the collimated laser light, (3) monitoring singleness of longitudinal mode and optical power of a light emitted from the grating, (4) calculating an orientation of the grating to exhibit intended optical power at which the singleness of longitudinal mode shows at least predetermined value, (5) adjusting the grating orientation or the optical axis of the collimated laser light to the calculated grating orientation.

Abstract: A method for processing data pixels in a holographic data storage system is disclosed. The method includes assigning predetermined reserved blocks throughout each data page, where each reserved block comprises known pixel patterns, determining position errors of the data page by computing the best match between regions of the data page and the predetermined reserved blocks, and compensating the data pixels at the detector in accordance with the corresponding position errors of the data page.

Abstract: Dynamic range enhancing dopants for photopolymeric media are described. Also described are optical articles using these dopants and methods for making such optical articles.

Abstract: A method and system is disclosed 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.

Abstract: Methods and systems for calculating a wavelength to use for a reference beam in recovering data from a holographic storage medium along with calculating a rotation and a tilt for the storage medium in data recovery. These systems and method include determining intensity levels for a plurality of windows (or subsets of pixels) for a data page as the angle of the reference beam is adjusted. The angles corresponding to the angles where the maximum intensity of light is detected for each window is then used in determining the wavelength, tilt, and rotation in recovering subsequent data pages from the holographic storage medium.

Abstract: The present invention provides systems and methods for logically organizing data for storage and recovery on a data storage medium using a multi-level format. The present invention also provides systems and methods for protecting data stored on data storage medium so that the data may be recovered without errors.

Abstract: The present invention provides systems and methods for logically organizing data for storage and recovery on a data storage medium using a multi-level format. The present invention also provides systems and methods for protecting data stored on data storage medium so that the data may be recovered without errors.

Abstract: A monocular holographic storage device or system to provide for compact recording and/or reading of data pages in a holographic storage medium. Also provided are methods for carrying out such data storage and/or data recovery using a monocular holographic storage device or system. Further provided are articles including holographic storage media for recording or for reading recorded data using such devices or systems.

Abstract: A holographic memory system is disclosed. The holographic memory system comprises: a light source configured to generate a light beam; a photosensitive holographic storage medium configured to at least partially reflect the light beam; and an alignment module configured to determine an angular orientation of the storage medium based on the reflected light beam.

Abstract: The present invention provides loading and unloading mechanisms for data storage cartridges, drive door mechanisms for data drives, and data drives comprising such loading and unloading and/or drive door mechanisms. Embodiments of the cartridge loading and unloading mechanisms, drive door mechanisms and/or data drives, of the present invention can operate in a manner such that the drive door of the data drive is fully closed before the disk medium is exposed, e.g., before opening of the associated shutter of the cartridge. An embodiment of the cartridge loading and unloading mechanism of the present invention can be powered by the same drive motor assembly that is used to move or transport the cartridge to the optical head assembly used for writing and/or reading of data from the disk medium of the cartridge. Embodiments of the cartridge loading and unloading mechanisms and drive door mechanisms of the present invention can fit within a standard configuration for a data drive.

Abstract: The present invention provides a scanner comprising: a base member; a scanning beam reflective member having a first tilt axis and a second tilt axis orthogonal to the first tilt axis; a mounting assembly for mounting the scanning beam reflective member on the base member for tilting of thereof along the first and second tilt axes; an actuator for tilting the scanning beam reflective member along the first and second tilt axes to provide a tilt orientation; a magnet assembly which generates one or more magnetic fields which are responsive and correlated to the tilt orientation; and a magnetic field sensor assembly for sensing the magnetic fields generated by the magnet assembly to thereby indicate the tilt orientation. The mounting assembly may comprise a suspension assembly having a tilt imparting assembly for imparting tilt to the reflective member, and a reflective member holder assembly for holding the reflective member.

Abstract: 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.

Abstract: A laminated holographic recording medium having (a) a first substrate having a through-hole and (b) a solid polymer matrix layer that records holographic data laminated to the first substrate and a method of manufacturing thereof are disclosed. The method of manufacturing preferably requires injecting a precursor material through the through-hole and polymerizing the precursor material in contact with the first substrate to form the polymer matrix layer.

Abstract: Holographic systems which shape coherent light beams are disclosed. These holographic systems may beam-shaping devices positioned in the path of coherent light beams to shape a coherent light beam into an essentially diffraction noise free coherent light beam of predetermined dimensions that has a continuous light beam profile of distinct intensity zones.

Abstract: The present invention relates to a system, as well as articles and holographic recording medium comprising the system, where the system comprises: a polymerizable component comprising at least one photoactive polymerizable material; and a photoinitiator component comprising at least one photoinitiator for causing the polymerizable component to polymerize to thereby form a plurality of holographic gratings when activated by exposure to a photoinitiating light source; wherein when a portion of the polymerizable component has been polymerized to form at least one holographic grating, the unpolymerized portion of the polymerizable component is resistant to further polymerization when not exposed to the photoinitiating light source. The present invention also provides methods for forming at least one holographic grating in a holographic recording medium having such a photopolymerizable system.

Abstract: An apparatus comprising: a processor for determining if a laser is operating in a single-mode state and for determining the degree to which one of one or more tunable parameters for the laser must be adjusted so that laser operates in a single-mode state if not operating in a single-mode state, wherein the one or more tunable parameters include the following parameters: the laser current and the wavelength of the output light. The apparatus may include a laser and/or a holographic storage medium. Also provided is a method for determining if a laser is operating in a single-mode state and for determining the degree to which one of one or more tunable parameters for the laser must be adjusted so that laser operates in a single-mode state if not operating in a single-mode state.