Abstract: Data recording tape is passed along guides and past a read/write head. Sensors detect the position of the tape and adjust the guides and the head as a function of the position. If the tape deviates from the target tape path, a controller moves a guide to steer the tape back to the target tape path, using the sensor signals. In cases of tape disturbance such as those involving rapid tape motion, an adaptive estimator uses the sensor signals to position the head to anticipate the expected position of the tape when the disturbance arrives at the head.

Abstract: A jewel case 10 for housing at least one piece of recording media is constructed from a blend of resins. The blend includes at least two resins, the first being a stiffer resin and the second, a flexible resin, wherein a clear and flexible jewel case is produced.

Abstract: A tape reel assembly including a hub, opposing upper and lower flanges, a plurality of reel teeth, and three engagement features. The opposing upper and lower flanges extend in a radial fashion from opposing sides of the hub. The reel teeth extend axially outwardly relative to the hub. The three engagement features are equidistantly spaced within the reel teeth and are configured to provide a dominant mating surface relative to surfaces of the plurality of reel teeth. With this configuration, the three engagement features mate with teeth of the tape drive clutch, and prevent meshed engagement with the remaining reel teeth. Thus, the three engagement features dictate the plane of contact between the tape reel assembly and the drive clutch, with the reel teeth serving as general guide surfaces that facilitate this interaction. The engagement features can be pronounced drive teeth or reduced-sized valleys.

Abstract: A mold and a process for use in producing data storage articles such as single substrate double-sided disks. In one configuration, a mold for manufacturing a substrate includes a stamper, at least one holder having an interface with the stamper, and a vacuum line for applying a retention force to maintain the interface between the holder and the stamper. In another configuration, the mold includes a demolding line for applying a demolding force to the substrate to aid in separating the substrate from the stamper. The various embodiments of the present invention provide, among other things, easier and faster stamper changeover, substrates and final data storage articles having improved process indicia such as thickness, flatness, inner and outer diameter, and concentricity, and facilitates production of single-substrate double-sided disks.

Abstract: A multi-layer optical storage medium includes a transparent substrate, a partially reflective layer, a transparent spacer, and a highly reflective layer. One pattern of data pits is provided on the substrate, adjacent the partially reflective layer, and another pattern of pits is provided on the spacer layer, adjacent the highly reflective layer. The partially reflective layer may be made of amorphous selenium (a-Se) and preferably has an index of refraction having a real component, n, greater than 2.8 and an imaginary component, K, less than 0.01. The invention also includes the optical data storage systems compatible with such media.

Abstract: The invention is generally directed to techniques for reducing premature drying of solvent-based coatings, including premature drying at sites on the apparatus that applies the coatings. By introduction of solvent vapor proximate to the coating apparatus, and by passively bringing the solvent vapor to the site, the risk of premature drying is reduced. In the presence of the solvent vapor, solvent in the coating fluid tends not to evaporate quickly. The solvent vapor may be introduced by any of a variety of solvent vapor emission devices, and may be brought to the site passively by, for example, increasing the concentration of solvent vapor in a boundary layer that moves with the substrate being coated, diffusion, or natural convection.

Abstract: Holographic data storage media having a sandwiched construction are described in which a holographic recording material is sandwiched between two substrates. A variety of different formulations of the holographic recording material are also described. By improving the formulation of the photosensitive material, holographic media can be improved.

Abstract: A method of determining the coercivity ratio of magnetic recording medium, and magnetic recording medium having a magnetizable layer with a Performance Coercivity Ratio (PCR) of at least 1.06 and preferably less than 1.4.

Abstract: An electro-optic modulator is driven between discrete operating points such that a reversal of applied field polarity reduces harmful charge screening effects and the voltage swing between the operating points is reduced from previously used voltage swings.

Abstract: A holographic optical data storage device according to the present invention includes a photopolymer layer having an upper surface and an oppositely disposed lower surface. The device includes a substantially transparent upper substrate layer having a first inside surface lying adjacent to the upper surface of the photopolymer layer. The device includes a substantially transparent lower substrate layer having a second inside surface lying adjacent to the lower surface of the photopolymer layer. The upper and lower substrates have first and second peripheral edges respectively with an opening formed therebetween. The device further includes a connection member engaged to the upper and lower substrates wherein the connection member seals the opening. A method of fabricating a holographic optical data storage device is also provided.

Abstract: A data storage tape cartridge is disclosed including a housing, a single tape reel, a storage tape, and a leader block. The housing includes a front, a back, a first side, a second side, a top, and a bottom. Further, the housing forms a leader block window, a lateral datum pad, and a longitudinal datum pad. The leader block window is formed at a corner defined by the front and the first side. The lateral datum pad is formed in the top. Finally, the longitudinal datum pad is formed in the front. The single tape reel is rotatably maintained within the housing. The storage tape is wrapped about the tape reel. The leader block is coupled to a leading end of the storage tape and is selectively secured to the housing at the leader block window. With this configuration, the lateral datum pad is configured to identify a top-to-bottom position of the tape reel. Similarly, the longitudinal datum pad is configured to identify a front-to-back position of the tape reel.

Abstract: An optical assaying method and system having a movable sensor is described. In one aspect, the present invention is a sensing system having a rotating sensor disk coated with indicator dyes sensitized to a variety of substances. In this configuration the sensing system further includes a detector for sensing spectral changes in light received from one or more of the indicator dyes. In another aspect, the present invention is a sensing system having a surface plasmon resonance sensor disk having grooves extending radially from a center of the disk. In yet another aspect, the present invention is a sensing system including a diffraction anomaly sensor disk having a dielectric layer that varies in thickness. The present invention allows for construction of an inexpensive sensing system that is capable of easily detecting a variety of substances either in a sample or a surrounding environment.

Abstract: A process of writing sector header data in the form of a stream of digital bits producing features located at varying radial positions on a master recording disk. Synchronized with rotation of the disk, a variable delay having a duration which varies with the radial positions of the bits on the disk is introduced into a clock signal. In the preferred embodiment, using the clock signal, a highly accurate, variable time delay is generated between the rotation of a master recording spindle and the recording of sector header data on a master disk mounted on the spindle. Thus, optical disks manufactured from the master disk have arc-shaped sector header spokes exhibiting maximum spatial accuracy and resultant maximal timing accuracy.

Abstract: Perpendicular magnetic media are described for use in magnetic recording and data storage. For example, a magnetic medium may include a substrate, an amorphous underlayer formed over the substrate, a seed layer formed over the amorphous underlayer, and a multi-layered magnetic stack formed over the seed layer. In this manner, high perpendicular magnetic anisotropy can be achieved and storage densities can be increased.

Abstract: A data storage tape cartridge including a housing, a tape reel assembly, a brake body, a spring, and a storage tape. The tape reel assembly includes a hub, opposing top and bottom flange components, brake teeth, and an inner surface. The inner surface is formed by the tape reel assembly and defines an engagement section apart from the brake teeth. The brake body includes a stem, a head, a toothed section, and a centering feature. The centering feature extends radially outwardly from the head and forms a circumferential edge that is radially spaced from the toothed section. A spring is positioned about a post formed by the cover to bias the brake body to a locked state. In the locked state, the toothed section engages the brake teeth to prevent rotation of the tape reel assembly. Interaction between the circumferential edge and the engagement section limits lateral shifting of the tape reel assembly relative to the tape reel opening when the data storage tape cartridge is vertically oriented.

Abstract: A winding flange guide (10) is utilized to provide a better quality wind of a strand media. The guide (10) has a first flange (12) and a second flange (13) which constrain the movement of the outer wraps of the tape pancake formed by the tape media. The winding flange guide (10) is utilized in a servo writer (20), tape cartridge (40, 60) and tape drive (80).

Abstract: A tape reel assembly for a data storage tape cartridge including a hub, and first and second flanges. The hub defines a hub axis and opposing first and second ends from which the flanges extend, respectively. The first flange includes a radially extending main body and an adjustment section. The adjustment section is provided within the main body, defines a tape edge contact surface, and is characterized by an increased flexibility as compared to the main body. The tape edge contact surface is readily deflectable relative to the hub axis. The adjustment section is configured such that a deflection orientation of the tape edge contact surface is a function of pressure on the hub. During use, as pressure on the hub increases (e.g., tape winding pressure), the adjustment section positions the tape edge contact surface to desirably direct the wound tape to a consistent lateral position.

Abstract: The invention is directed toward techniques for stamping optical data storage disks. A master is first created to include several distinct information regions etched upon a master surface. The master is then used to create one or more stampers. The stampers include a number of distinct stamper regions in locations corresponding to locations of the distinct information regions on the master. The stamper is then used to create a number of first replica disks that include distinct replicated regions. The distinct replicated regions are removed from the first replica disks to define second disks.

Abstract: Drying a coated substrate which includes magnetic particles includes a condensing surface spaced from the substrate. This creates a longitudinal gap between the substrate and the condensing surface. Liquid is evaporated from the substrate to create a vapor and the vapor is transported to the condensing surface without requiring applied convection. The vapor is condensed on the condensing surface to create a condensate which is removed from the condensing surface. Removal is performed, using more than gravity, without allowing non-uniformities of the condensate film to occur. The magnetic particles are oriented on the coated substrate by subjecting the coated substrate to a magnetic field created at a location outside of the dryer space.