Abstract: An optical data storage medium is provided. The optical data storage medium includes a polymer matrix; a reactant capable of undergoing a change upon triplet excitation, thereby causing a refractive index change; and a non-linear sensitizer capable of absorbing actinic radiation to cause upper triplet energy transfer to said reactant. The refractive index change capacity of the medium is at least about 0.1. The reactant comprises polyvinyl chlorocinnamate, polyvinyl methoxycinnamate, or a combination thereof.

Abstract: An optical article is provided. The optical article includes a first layer. The first layer includes an active holographic layer configured to store holographic data. The first layer has a first surface and a second surface. A second layer includes a low birefringence material. The second layer also has a first surface and a second surface. Guide grooves are present in any one of the first layer or the second layer. In certain embodiments, the article may further include a reflective layer, an anti-reflective layer, a barrier layer, and a combination thereof.

Abstract: There are provided compositions, optical data storage media and methods of using the optical data storage. The compositions comprise a non-linear sensitizer comprising one or more platinum ethynyl complexes capable of absorbing actinic radiation to cause upper triplet energy transfer to a reactant that undergoes a photochemical change upon triplet excitation.

Abstract: There are provided optical data storage media and methods of optical data storage using the same. The optical data storage media comprises a non-linear sensitizer capable of absorbing actinic radiation to cause upper triplet energy transfer to a reactant that undergoes change upon triplet excitation. The refractive index change (?n) of the medium is at least about 0.005, or even at least about 0.05.

Abstract: There are provided compositions, optical data storage media and methods of using the optical data storage media. The compositions comprise a non-linear sensitizer comprising one or more subphthalocyanine reverse saturable absorbers capable of absorbing actinic radiation to cause upper triplet energy transfer to a reactant that undergoes a photochemical change upon triplet excitation.

Abstract: There are provided an optical data storage medium and methods of optical data storage using the same. The optical data storage medium comprises a non-linear sensitizer capable of absorbing actinic radiation to cause upper triplet energy transfer to a reactant that undergoes a photochemical change upon triplet excitation.

Abstract: The present techniques provide methods and systems reading a data bit of interest on an optical data disc with a reduced error rate. The data bit estimation may be improved by reducing deterministic noise resulting from an optical reader system and/or the optical data disc. The reader may adjust the position of a detector to detect light scattered from the disc based on parameters of known noise sources. In one embodiment, the detector may be moved vertically in relation to the data bit of interest on the optical disc. In another embodiment, more than one detector may be used to detect light scattered from a data bit of interest. In embodiments, the positioning of the detector(s) may be based on system or disc parameters, and the detected scatterings may provide a data reading, improved for an optical return from a present micro-hologram.

Abstract: An optical disc for micro-holographic data storage, including: optically-enabled material configured to store holographic data; guide grooves; a first coating disposed on the guide grooves and configured to reflect a tracking beam and to transmit a read or record beam; and a second coating disposed to cover the guide grooves and disposed on the first coating.

Abstract: A system and method for replicating optical data storage discs (e.g., holographic data storage discs) having multiple layers of data. Master discs providing for respective single layers of data are utilized, and each respective single layer of data from the master discs are replicate onto the optical data storage disc.

Abstract: A system and method of operating a dual-beam detection system of a holographic data storage disc, including: impinging a data beam on a data layer of the holographic data storage disc; impinging a tracking beam on a tracking element of the holographic data storage disc; detecting a reflection of the tracking beam from the tracking element; and coordinating position of the data beam relative to the tracking beam.

Abstract: A system and method for controlling tracking in a holographic data storage system, including: impinging a beam on a holographic data disc, wherein the beam is reflected from a micro-hologram disposed within the holographic data disc; detecting the reflected beam from the holographic data disc by a multi-element detector; and analyzing a pattern detected by multi-element detector to generate a tracking error signal.

Abstract: A data storage device including: a plastic substrate having a plurality of volumes arranged in tracks along a plurality of vertically stacked, laterally extending layers therein; and, a plurality of micro-holograms each contained in a corresponding one of the volumes; herein, the presence or absence of a micro-hologram in each of the volumes is indicative of a corresponding portion of data stored.

Abstract: A data storage device including: a plastic substrate having a plurality of data volumes arranged along tracks in a plurality of stacked layers; a plurality of micro-holograms each contained in a corresponding one of the data volumes; a plurality of complementary volumes, each corresponding to and being substantially aligned with one of the data volumes; a plurality of micro-holograms each contained in a corresponding one of the complementary volumes; wherein, the presence or absence of a micro-hologram in each of the data volumes is indicative of a corresponding portion of data stored; and, the ones of the complementary volumes corresponding to the ones of the data volumes containing a micro-hologram do not contain a micro-hologram; and the ones of the complementary volumes corresponding to the ones of the data volumes not containing a micro-hologram contain a micro-hologram.

Abstract: The present techniques provide methods and systems for more reliable reading of optical data disks. In embodiments, a multi-pixel detector that is segmented into multiple areas, or detector segments, may be used to detect a pattern in the light reflected from an optical data disk. The pattern may include light scattered from a single bit that may be under a center detector, as well as light scattered from proximate bits. The detector system may then combine the quantized values from each of the detector segments mathematically to determine the presence or absence of a bit or bits of data. The mathematical combination may also use data that is known about the status of adjacent data bits (such as previously read bits, or bit patterns which are allowed or not allowed by specific data encoding schemes) to improve the accuracy of the bit prediction.

Abstract: A system for use with a data storage media having at least one groove proximate a surface thereof and a plurality of volumes therein, including: objective lensing; a first tracking error detector optically coupled to the objective lensing and being responsive to reflections from the at least one groove; a first actuator coupled and responsive to the first tracking error detector; a second tracking error detector optically coupled to the objective lensing and responsive to reflections from micro-holograms contained in at least some of the volumes; and, a second actuator coupled and responsive to the second tracking error detector; wherein the first and second actuators cooperate to selectively position the objective lensing to focus a light beam into a target one of the volumes.

Abstract: A system and method of controlling position of a pick-up head of an optical drive, including manipulating the position of the pick-up head as a primary variable in a cascade control scheme, and manipulating current flowing through the pick-up head as a secondary variable in the cascade control scheme.

Abstract: The present techniques provide methods and systems for reading and processing a data signal read from an optical data disc. In embodiments, an optical reader system may read data bits from a data ring in the disc. The data rings may be concentric, and a beginning of a sequence of data on the data ring may be in substantially the same position as an ending of the sequence. The reader may identify a data ring and begin the read process on the targeted data ring, and may end the read process when the reader reaches the starting point. The data sequence read from the data ring may be decoded to form a bit stream, which may be provided to various output devices. A circular trellis formed from the bit stream may enable the reading of a targeted data sequence without additional tail bits to improve data transmission efficiency.

Abstract: A data storage device comprises a substrate having oppositely disposed surfaces and a plurality of volumes arranged along tracks between the surfaces; a plurality of micro-holograms each contained in a corresponding one of the volumes; and, at least one groove in at least one of the surfaces and being operative to diffract light through the at least one surface and into the volumes; wherein, the presence or absence of a micro-hologram in a stacked layer in each of the volumes is indicative of a corresponding portion of data stored.

Abstract: The present techniques provide systems and methods for modulation coding of data on optical disks, such as holographic data disks, and techniques for reading that data back from the disks. The techniques involve parsing a bit stream into a sequence of individual bit-patterns, and then using the individual bit patterns to select a symbol, or matrix, from a lookup table of previously selected matrices. The symbols are selected according to predetermined criteria that may help make the disk more resistant to interferences and errors, such as surface scratches, and the like. For example, criteria that may be used to select the symbols are the number of reflective and non-reflective regions within each matrix, and the number of sequential reflective regions, among others. The symbols may be written to the disk in a two-dimensional fashion, e.g., across adjacent tracks, or in a three-dimensional fashion, e.g., across adjacent data layers.

Abstract: The present techniques present methods and systems for increasing a data reading rate on optical data disks using a single reading head. The methods take advantage of the difference between a mean focal distance (MFD), or minimum spacing that the detector can distinguish between bits, and the minimum separation of bits in a single track to increase the reading speed. As the bits may be more closely spaced across adjacent tracks or layers, these techniques may be used to increase the reading speed of the disk. Specifically, the data symbols that make up a single bit-stream may be stored in a pattern horizontally across adjacent tracks, or vertically across adjacent layers. Accordingly, the focal point of the detector is scanned across the disk in the same pattern to read the individual data symbols.