Abstract: A magneto-optic head includes a magnetic layer formed to have a substantially stabilized magnetic domain configuration. The magnetic layer includes a set of magnetic domains that includes one or more magnetic domains that are oriented such that they are substantially parallel to a major axis of the magnetic layer. In exemplary embodiments, the magnetic layer is deposited over a non-magnetic substrate and patterned, e.g., etched, in such a way that ordered magnetic domains form within the magnetic layer. For example, the magnetic layer may be patterned to have a height and width-to-height aspect ratio that yields one or more magnetic domains that are oriented such that they are substantially parallel to a major axis of the magnetic layer. In some embodiments, two magnetic layers are antiferromagnetically exchange coupled such that each magnetic layer includes a magnetic domain that is oriented substantially parallel to the major axis of that magnetic layer.

Abstract: The invention is directed to patterns of amplitude-based servo windows that eliminate the need for conventional track identification marks, and various servo writing devices and head configurations that facilitate creation of such servo patterns. The patterns of servo windows may also eliminate the need for conventional synchronization marks. In accordance with the invention, the patterns of servo windows, themselves, can distinguish one track from another track in one or more servo bands and inherently provide synchronization without the need for synchronization marks between servo frames. In other words, the same amplitude-based servo windows that define the centerlines of the tracks can be arranged to provide track identification information and possibly inherent synchronization information.

Abstract: Time-based servopositioning systems, methods, formats, and data recording media used in association with the same, employing bands of signals that differ from each other in the polarity of the servo signal, or the orientation of the servo signal, or the pattern width of the servo signal.

Abstract: A servo pattern is described that facilitates high resolution and wide dynamic range to accurately pinpoint servo track centerlines on a magnetic tape. The servo pattern provides both absolute positioning information over an entire servo band and absolute positioning information relative to the centerline of each servo track included in the servo band. Therefore, the servo pattern includes implicit servo track identification in a single servo band, eliminating the need for conventional track identification marks. In other words, the servo pattern, itself, can distinguish one servo track from another servo track in the single servo band as well as provide highly accurate positioning information relative to each of the servo track centerlines.

Abstract: The invention presents techniques for verifying patterns, such as time-based servo marks, recorded on magnetic media. Patterns of this kind can be recorded on a magnetic medium using a recording head that includes a surface having a flux gap with a defined shape. The patterns may be verified with a verify head, having a surface with a flux gap with the defined shape or part of the defined shape. The verify head may include two or more ferromagnetic cores, with a flux gap associated with each core. Each core can independently verify part of the recorded pattern.

Abstract: A servo pattern is described that facilitates high resolution and wide dynamic range to accurately pinpoint servo track centerlines on a magnetic tape. The servo pattern provides both absolute positioning information over an entire servo band and absolute positioning information relative to the centerline of each servo track included in the servo band. Therefore, the servo pattern includes implicit servo track identification in a single servo band, eliminating the need for conventional track identification marks. In other words, the servo pattern, itself, can distinguish one servo track from another servo track in the single servo band as well as provide highly accurate positioning information relative to each of the servo track centerlines.

Abstract: The invention provides a read-while-write recording system for a linear data storage medium, such as magnetic tape or other data storage medium in which data is stored on parallel data tracks that extend along a length of the medium. The invention makes use of separate sliders for the read and write elements, and separate actuators to control the positioning of the sliders. Each of the sliders may also include servo elements to read servo marks. In order to limit the effect of movement of the first slider on the positioning of the second slider, a tape guide is implemented between the different sliders.

Abstract: The invention is directed to a non-rotating head used in linear scanning of linear magnetic tape. For example, the head may include a non-rotating contoured surface shaped to facilitate flyability of linear magnetic tape passing over the non-rotating contoured surface. A contact area defining a magnetic gap may protrude from the surface. The contact area that projects from the surface can contact the magnetic tape to read data from the tape and/or write data to the tape as the tape flies over the surface.

Abstract: The invention is directed to patterns of amplitude-based servo windows that eliminate the need for conventional track identification marks, and various servo writing devices and head configurations that facilitate creation of such servo patterns. The patterns of servo windows may also eliminate the need for conventional synchronization marks. In accordance with the invention, the patterns of servo windows, themselves, can distinguish one track from another track in one or more servo bands and inherently provide synchronization without the need for synchronization marks between servo frames. In other words, the same amplitude-based servo windows that define the centerlines of the tracks can be arranged to provide track identification information and possibly inherent synchronization information.

Abstract: The invention is directed to patterns of amplitude-based servo windows that eliminate the need for conventional track identification marks, and various servo writing devices and head configurations that facilitate creation of such servo patterns. The patterns of servo windows may also eliminate the need for conventional synchronization marks. In accordance with the invention, the patterns of servo windows, themselves, can distinguish one track from another track in one or more servo bands and inherently provide synchronization without the need for synchronization marks between servo frames. In other words, the same amplitude-based servo windows that define the centerlines of the tracks can be arranged to provide track identification information and possibly inherent synchronization information.

Abstract: Servopositioning data is written onto a linear recording medium such that a position error signal (PES) is intentionally created. The signal substantially resembles a conventional time based servo pattern, but is insensitive to transverse position. In a preferred embodiment, the signal at a zero-azimuth, i.e., an angle sufficiently small in value such that there is no significant PES signal associated with the transverse motion.

Abstract: The invention contemplates a disk based data storage unit. The storage unit includes a plurality of disk drives all within a self-contained unit. The data storage unit may resemble a suitcase and may be ruggedized. The data storage unit may include a handle and possibly wheels to simplify transport of the data storage unit. The data storage unit can replace a plurality of tape cartridges or disk cartridges. A user backs up data onto the storage unit and then moves the storage unit off-site. The suitcase-like form factor and suitcase transporting features allow for easy transport of a large volume of data. Emulation may be used to facilitate communication between the data storage unit and a host computer executing data storage tape software commonly used in data backup and archive applications.

Abstract: A servo head comprising a write gap with a non-uniform width is described. It allows non-uniform width servo marks to be recorded on magnetic media. A servo head having a non-uniform width gap may create servo marks that facilitate servo position error signal calculations using time-based methods, amplitude-based methods, or both. This invention provides alternative methods for positioning servo heads and may increase reliability and precision by allowing redundant calculations.

Abstract: In general, the invention relates to a data storage tape including servo information on both sides of the tape. Techniques for writing servo information to both sides of the data storage tape are also described. For example, a mechanical arrangement of two servo write heads positioned with respect to the data storage tape can enable two-sided servo recording. In addition, a single servo write head may be used to write servo information to both sides of the data storage tape with the aid of a flux conductor. In that case, the magnetic field of the servo write head passes through the data storage tape to record servo information on both sides of the tape.

Abstract: Servo positioning systems, methods, formats, and data recording media used in association with the same, employing additional timing reference information to improve immunity to time-based errors caused by instantaneous speed variations.

Abstract: Magnetic data storage media having recording layers that include microscopic surface protrusions are described. A recording head of a magnetic drive may contact the protrusions, i.e., the protrusion tops may define a load bearing surface area of the recording layers of such media. The heights of the protrusions under the recording head and distribution of the protrusions on the recording layers of such media may be substantially uniform. The load bearing surface area may be relatively small when compared to the total surface areas of the recording layers of such media. Also, the average distance between any two adjacent protrusions on such media may be defined based on the length of bits recorded thereon.

Abstract: Time-based servo positioning systems, methods, formats, and data recording media used in association with the same, employing full amplitude recording signals to improve the available signal as media thicknesses decrease.

Abstract: A thin film servo head apparatus is described that provides verification of time-based servo marks on a magnetic tape. The thin film servo head apparatus includes a plurality of thin film servo heads formed in a substrate. The substrate is canted such that servo gaps included in each of the thin film servo heads are substantially parallel to the time-based servo marks. Thin film servo heads eliminate the high labor, low yield machining process associated with conventional ferrite composite servo heads. Thin film servo heads may be fabricated in bulk on substrate wafers to reduce manufacturing time and cost. The invention described herein enables thin film servo heads to be used with time-based servo markings by defining a servo gap spacing such that when the substrate is canted, the servo gaps of the thin film servo heads substantially align with the time-based servo markings.

Abstract: The invention is directed to a magnetic storage medium recorded with an amplitude-based servo pattern in which one or more first servo windows positioned above a centerline of a servo track have a different width than one or more second servo windows positioned below the centerline. The first servo windows may be larger or smaller than the second servo windows. In either case, by detecting the widths of the servo windows and detecting signal amplitude as a servo head passes relative to the servo track, servo tracking can be achieved without the use or need for additional synchronization marks in the servo pattern.

Abstract: In general, the invention provides two-sided magnetic data storage tape comprising azimuthal magnetic transition layouts that can substantially reduce demagnetization of recorded magnetic transitions on the surfaces of the tape. The invention specifically balances the goal of simplified media manufacture with the goal of reducing or avoiding media degradation when the tape is spooled. The two-sided magnetic data storage tape defines a substantially similar easy axis of magnetic anisotropy on a first and a second side of the tape, which can simplify media manufacture. Recorded magnetic transitions on the opposing sides of the tape define azimuths that are substantially different, which can help avoid media degradation when the tape is spooled.