Imation Corporation

Other

Douglas W Johnson

Richard W Molstad

Yung Yip

Denis J Langlois

Larold L Olson

Stephen J Rothermel

Christopher J Zwettler

James S Anderson

Michael P Sharrock

Robert W Tapani

William Joseph Vanderheyden

Daniel Charles Egan

Saeed Fahimi

Durkee B Richards

David A Gobran

Roni J Dornfeld

Michael J Kelly

Leif O Erickson

Jerry Lee Alexander

Michael W Johnson

Michael A Mewes

Alan Olson

Richard E Jewett

Mark P Weber

Charles L Dennis

C Thomas Jennings

Brian D Findlay

Allan R Markert

Wayne P Schaefer

John D Willems

Albert E Bass, Jr

A method comprises generating first and second magnetic field components in a magnetic medium, the second magnetic field component substantially opposite the first. A pattern is written onto the magnetic medium, and a signal is generated by reading the pattern. The magnitude of the second magnetic field component is controlled based on an asymmetry of the signal.

Methods and systems for magnetic media servo writing

The present disclosure relates to a perpendicular pole head for creating a perpendicular magnetic moment in a concentrated pattern for writing the pattern on perpendicular magnetic media, such as BaFe based media. The pole head can have flux concentrators in the shape of the written pattern, which can be repeatedly applied to a moving magnetic medium to create a timing pattern on the media, e.g., a servo timing pattern.

Perpendicular pole head for servo writing magnetic media

A system comprises a first tapered core configured for positioning adjacent a first surface of a magnetic medium, and a second tapered core configured for positioning adjacent a second surface of the magnetic medium, opposite the first tapered core along a travel direction of the magnetic medium. Each of the first and second tapered cores has a transverse width defined with respect to the magnetic medium, where the transverse width decreases from a first end of the tapered core to a second end of the tapered core, the second end forming a pole face adjacent the magnetic medium.

Tapered pole heads for magnetic media

Magnetic storage tape and techniques for erasing and writing to magnetic storage tape having a perpendicular squareness greater than 50 percent and a longitudinal squareness less than 50 percent are described. In general, the magnetic tape may be biased with a remanence magnetization, or magnetic orientation, in any direction. One or two head systems may use various magnetic field patterns to create the desired remanence magnetization. Servo marks may have a remanence magnetization in an opposite magnetic orientation than that of the remaining bias on the servo track, e.g., substantially perpendicular to the magnetic tape. In some examples, a write head may alternate the direction of the magnetic field to continuously bias and write servo patterns to the magnetic tape. In addition, a symmetrical servo mark may be created in the magnetic tape with a write head having a gap width approximately equal to the length of the servo mark.

Erasure of magnetic storage media having perpendicular anisotropy

Continuous biasing and servowriting of magnetic storage media having perpendicular anisotropy

Servo mark length matched to write head gap for magnetic storage media

Erasure and servowriting of magnetic storage media having perpendicular anistropy

A system comprises a magnetic medium with a first magnetic gap adjacent a first side and a second magnetic gap adjacent a second side, opposite the first magnetic gap. The first magnetic gap generates first longitudinal and perpendicular field components. The second magnetic gap generates second longitudinal and perpendicular field components. The first and second longitudinal field components are substantially aligned along a recording layer of the magnetic medium, and the first and second perpendicular field components are substantially opposed across the recording layer of the magnetic medium.

Systems and methods for processing magnetic media with first and second magnetic gaps adjacent opposite sides of the recording layer

The invention is directed to a data storage medium that includes a plurality of servo bands distributed across the data storage medium and a plurality of data tracks positioned between each of the plurality of distributed servo bands. The data storage medium comprises a servo band pitch of less than 200 micrometers. The large number of servo bands distributed across the data storage medium with a relatively small servo band pitch reduces the influence of media dimensional instability. In this way, the invention may substantially increase data read head positioning accuracy, especially in the case of narrow track widths. A read head array arranged in a two-dimensional matrix that includes a first servo read head, a second servo read head, and a plurality of data read heads positioned between the first and second servo read heads may be applied to a data storage medium as described herein.

Distributed servo patterns for data storage media

The invention is directed to techniques for erasing data storage tape for reuse. In an embodiment, an erase head module for erasing data storage tape comprises a set of erase gaps and one or more servo read elements. The set of erase gaps is configured to coincide with data bands of the data storage tape to allow erasure of only the data bands of the data storage tape while not erasing servo bands of the data storage tape. The one or more servo read elements detect one of the servo bands of the data storage tape when the set of erase gaps are proximate the data bands of the data storage tape to allow the erase head module to accurately track the data bands with the set of erase gaps.

Data storage tape recertification

In an embodiment, a data storage tape includes a first side including recorded data and a second side including recorded error correcting code data for the recorded data on the first side. In another embodiment, a data storage tape comprises a first side including recorded data and a second side including a copy of the recorded data. Embodiments of the invention may distribute related data across both sides of a data storage tape and as a result may reduce the probability that a location-dependent error in the data storage tape will result in irretrievable data loss. Embodiments of the invention may be particularly useful for systems that can simultaneously retrieve or record data on both sides of a dual-sided data storage tape.

Robust data storage techniques for two-sided data storage tape

In general, the invention is directed to servo techniques that utilize servo patterns to facilitate head positioning relative to the data tracks. For example, the servo techniques may include a first series of servo patterns configured to allow calculation of a position error signal that substantially mitigates error resulting from a variation in velocity of the data storage tape during detection of the at least one of the servo patterns in the first series. The servo techniques may also include a second series of servo patterns interleaved within the first series of servo patterns in order to encode data. The encoded data may include linear position information. Embodiments may allow a data storage tape meeting a currently accepted data storage tape specification, e.g., an LTO Ultrium specification, to record data in a higher density than currently implemented with the specification.

Interleaved servo pattern

The invention is directed to techniques for storing information on a linear data storage medium, such as magnetic tape. According to the invention, a write head array concurrently writes a plurality of data tracks and at least one servo track onto the magnetic tape. In this way, the servo track is integrated between the data tracks. The servo track may, for instance, be located in the middle of a data band, and may span a distance corresponding to two data tracks. By concurrently writing the servo track with the data tracks, track misregistration (TMR) can be reduced or eliminated during the write operation.

Concurrent servo and data track writing

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Stillwater, MN, United States of America

Douglas W Johnson