US20070230040A1 - Timing-based servo verify head and method thereof - Google Patents

Timing-based servo verify head and method thereof Download PDF

Info

Publication number
US20070230040A1
US20070230040A1 US11693489 US69348907A US2007230040A1 US 20070230040 A1 US20070230040 A1 US 20070230040A1 US 11693489 US11693489 US 11693489 US 69348907 A US69348907 A US 69348907A US 2007230040 A1 US2007230040 A1 US 2007230040A1
Authority
US
Grant status
Application
Patent type
Prior art keywords
magnetic
head
servo
fig
gap
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US11693489
Inventor
Matthew Dugas
Gregory Wagner
Original Assignee
Dugas Matthew P
Wagner Gregory L
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

Links

Images

Classifications

    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127Structure or manufacture of heads, e.g. inductive
    • G11B5/265Structure or manufacture of a head with more than one gap for erasing, recording or reproducing on the same track
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
    • G11B5/58Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B5/584Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for track following on tapes

Abstract

A servo head capable of verifying at least one timing based pattern printed on media is provided. The servo head includes a magnetic structure having at least one magnetic element arranged and configured to form at least one magnetic gap parallel to the timing based pattern. In one embodiment, the magnetic element is arranged and configured to have a plurality of magnetic gaps being parallel to each other but not co-linear to each other. In the second embodiment, the magnetic element is arranged and configured to have a magnetic gap being parallel to and co-linear to the timing based pattern.

Description

    CROSS-REFERENCE TO RELATED APPLICATION(S)
  • [0001]
    This application claims the benefit of U.S. Provisional application No. 60/530,943, entitled “Time-Based Servo Heads Using Discrete Single Channel Head Elements and Methods for Making the Same,” filed on Dec. 19, 2003, the subject matter of which is hereby incorporated by reference herein in its entirety.
  • FIELD OF THE INVENTION
  • [0002]
    The present invention relates generally to recording and reading data from magnetic storage media and, more particularly, to a magnetic head and method thereof for verifying timing-based servo tracks or patterns on magnetic storage media.
  • BACKGROUND OF THE INVENTION
  • [0003]
    Due to the density of modern magnetic data storage media, magnetic data storage media requires servo tracks be printed onto the media to minimize data-track registration errors. The servo tracks are often written onto the storage media in the media production facility, where it is necessary, after writing servo tracks or patterns, to verify that the tracks have been properly printed onto the media and meet the production specifications. This verification process is accomplished by running a servo verify magnetic recording head, e.g. read head, over the media on which the servo tracks are printed.
  • [0004]
    A servo head, in this case particularly a servo verify head, generally requires an ensemble of magnetic structures. Standard processing techniques and tools for assembling magnetic structures generally operate in an orthonormal coordinate system. Thus, the processing of magnetic structures at an angle to the standard processing planes poses unique challenges.
  • [0005]
    In the magnetic data storage media industry, there are many methods of writing or implementing magnetic servo tracks on storage media. Servo tracks have many different geometries. One specific method and geometry is that of timing based servo (TBS). TBS utilizes successive magnetic transitions written on the media at non-orthogonal angles with respect to the travel direction of the media (e.g. tape). FIG. 2 a illustrates this method. Two separate servo bands 42 are shown, with a set of four magnetic patterns or tracks 40 a and 40 b at +6° and −6° respectively.
  • [0006]
    The uniqueness of TBS patterns is due to magnetic structures at an angle to standard processing planes, i.e. non-orthogonal angles with respect to the travel direction of media. To verify TBS patterns or tracks on the media, it is desired that the magnetic sensing regions (read gap) on a servo verify head are effectively parallel to the corresponding magnetic transitions (servo patterns) printed on the media. Non-parallelism between the magnetic transition on the tape and the magnetic read head may lead to detection inefficiencies and lower sensitivity of the resultant signals through azimuth loss.
  • [0007]
    One method for verifying a TBS pattern is to sense or read a full servo transition at once, a so-called full-band verify. With this method, the full pattern width of any single transition is detected at once. With full-band verify, it is desirable to have good azimuth alignment between the magnetic head read gap and the servo transition on tape. Misalignment between these will cause the magnetic transition to be effectively smeared across the read sensor, causing detection efficiency and sensing accuracy loss. Severe azimuth misalignment, may even cause more than one magnetic transition to be intersecting the read sensor (gap) simultaneously, confusing what transition was verified.
  • [0008]
    Another method for verifying a TBS pattern is the so-called partial-band verify. With this method, a narrow read gap magnetic head is used. If the read gap width is sufficiently small relative to the TBS pattern width, the amount of azimuth misalignment acceptable is eased. In one example, a TBS pattern with a width of 190 μm at an angle of 6° can be verified by a read sensor with a width of 5-10 μm at an azimuth angle of 0°. This method allows the production of a servo verify head without the complexity of processing previously mentioned. This method also requires that the servo verify head be mechanically scanned along the TBS pattern transition width to sample the full servo pattern. Both the above mentioned methods have advantages and disadvantages and are practiced in the industry.
  • [0009]
    One advantage of the full-band verify method is that the head is stationary, eliminating the need for a scanning actuator to move the head in the cross-track direction. Another advantage of the full-band verify method is that the entire width of each pattern in the servo band is verified. On the other hand, it may be difficult for the full-band verify method to detect small localized defects in the servo pattern. In one example, a localized defect of 5 μm along a 190 μm track width, which is repeated down the servo band, may not be properly detected.
  • [0010]
    One advantage of the partial-verify method is that the repeatable small local defects previously mentioned can be intersected and properly detected as the head scans back and forth. In a partial-verify method, however, an appropriate scan rate, i.e., how long it takes to scan the width of a servo band, may be desired in representing the fraction of any servo pattern sampled. Large temporary defects where a significant portion of a servo pattern is missing, and where the defects only repeat for a small number of servo patterns, may not be intersected by the scanning head and hence be undetected. Hence, it is desirable to detect these defects with an appropriate scan rate and in an efficient and capable manner in the production facility.
  • [0011]
    Also, in the processing of magnetic structures of a servo head for verifying TBS patterns, independent channels at a specified angle are desired. This allows each servo pattern and any defects of that servo pattern to be detected independent of any other servo pattern.
  • [0012]
    Further, in the processing of magnetic structures of a servo head for verifying TBS patterns, it is desirable to assemble or bond independent cores while maintaining multi-dimensional tolerances.
  • [0013]
    An additional feature of a magnetic servo verify head is a proper head to tape interface. If the head to tape interface is poor, the tape may not contact the head appropriately, leading to sensing inefficiency. A magnetic head surface generally requires an appropriate geometry to obtain a good or acceptable head to tape interface. One standard geometry for a magnetic servo head used in the industry is a cylindrical contour. As an example, typical cylindrical contours may have a radius from 5 mm to 25 mm. A cylindrical contour generally limits the length of the head (down-tape or down-track direction) to achieve a good interface. Therefore, the spatial location acceptable for magnetic elements on a cylindrical contour is restricted.
  • [0014]
    Thus, depending on the desirable geometry and form factor of a magnetic servo head surface, TBS patterns may add a high degree of complexity to processing techniques of the ensemble of magnetic structures for a servo verify head.
  • [0015]
    Therefore, there is a need for a servo head to verify TBS patterns printed on data storage media, and further there is a need for a method of assembling a servo head having acceptable head geometry and form factor of a servo head surface to be adapted for verifying TBS patterns.
  • SUMMARY OF THE INVENTION
  • [0016]
    In accordance with the present invention, a servo head or servo verify head capable of verifying at least one timing based pattern printed on media comprises a magnetic structure including at least one magnetic bar or magnetic element arranged and configured to form at least one magnetic gap parallel to the timing based pattern. In one embodiment, the magnetic element is arranged and configured to have a plurality of magnetic gaps being parallel to each other but not co-linear to each other. In the second embodiment, the magnetic element is arranged and configured to have a plurality of magnetic gaps being both parallel and co-linear to each other.
  • [0017]
    Further in one embodiment of the present invention, the magnetic element includes a plurality of individual gap bars bonded to each other, each gap bar having a pair of magnetic cores bonded together with the magnetic gap disposed therebetween. The magnetic gap is an angled gap which is non-orthogonal to an edge of the magnetic element.
  • [0018]
    Also, in accordance with the present invention, a method of forming a servo head capable of verifying at least one timing based pattern printed on media comprises the steps of: providing a magnetic gap element having a pair of magnetic element elements bonded together with a magnetic gap disposed therebetween, the magnetic gap extending linearly along the element and being parallel to the timing based pattern.
  • [0019]
    In one embodiment, the method further comprises the steps of: dicing the magnetic gap element into individual cores at an angle to the magnetic gap such that the magnetic gap is non-orthogonal to an edge of the magnetic element; and assembling the cores into a composite structure on a reference block, such that the gaps of the cores are parallel to each other.
  • [0020]
    Still in one embodiment, the method further comprises the steps of: bonding the cores against the reference block by spring means; removing a portion of the composite structure to form an azimuthal multicore which includes a plurality of magnetic structures on one side of the azimuthal multicore, and each magnetic structure including a magnetic gap; bonding a slider element onto the azimuthal multicore; and exposing the magnetic structures including the magnetic gaps, wherein the magnetic gaps are parallel to each other.
  • [0021]
    Additionally in one embodiment, the method further comprises the steps of: processing a second magnetic gap element having exposed magnetic structures including magnetic gaps wherein the magnetic gaps are parallel to each other and a slider element bonded onto an azimuthal multicore; bonding the first magnetic gap element and the second magnetic gap element onto a spacer disposed therebetween.
  • [0022]
    In the second embodiment of the present invention, the magnetic structure includes a first gap element having a first pair of magnetic cores bonded together with a first magnetic gap disposed therebetween, and a second gap element having a second pair of magnetic cores bonded together with a second magnetic gap disposed therebetween. The first and second magnetic elements are arranged and configured to be bonded onto a spacer disposed therebetween such that the first and second magnetic gaps are angled and parallel to the timing based patterns on the media and are non-orthogonal to an edge of the magnetic structure.
  • [0023]
    Also, in accordance with the second embodiment of the present invention, the method of forming a servo head capable of verifying at least one timing based pattern printed on media further comprises the steps of: removing a portion of the magnetic element to form a plurality of magnetic structures on one side of the magnetic element, and each magnetic structure including a magnetic gap; bonding a slider element onto the magnetic structures; and exposing the magnetic structures including the magnetic gaps.
  • [0024]
    Additionally in the second embodiment, the method further comprises the steps of: processing a second magnetic gap element having exposed magnetic structures including magnetic gaps; bonding a second slider element onto the magnetic structures; exposing the magnetic structures including the magnetic gaps; and bonding the first magnetic gap element and the second magnetic gap element onto a spacer disposed therebetween.
  • [0025]
    Further, in accordance with the present invention, the magnetic element is a thin film head row bar.
  • [0026]
    Further in one embodiment of the present invention, one servo verify head covers the entire length of the timing based patterns so as to verify the timing based patterns in its entirety at the same time. In another embodiment, a plurality of servo verify heads cover the entire length of the timing based patterns so as to verify the timing based patterns in its entirety at the same time. In a third embodiment, a servo verify head covers a part of the entire length of the timing based patterns and scans the timing based patterns by moving the servo verify head along the patterns.
  • [0027]
    While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the invention is capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0028]
    FIG. 1 illustrates a perspective view of one embodiment of a timing-based servo verify head in accordance with the principles of the present invention.
  • [0029]
    FIG. 2 illustrates a flow chart of one exemplary process of forming a timing-based servo verify head in accordance with the principles of the present invention.
  • [0030]
    FIG. 2 a illustrates a top view of one embodiment of a timing-based servo pattern on a magnetic tape.
  • [0031]
    FIG. 3 illustrates a perspective view of one embodiment of a core bar in the process of forming a timing-based servo verify head of FIG. 1 in accordance with the principles of the present invention.
  • [0032]
    FIG. 4 illustrates a perspective view of one embodiment of an individual core piece formed from the core bar of FIG. 3 in the process of forming a timing-based servo verify head of FIG. 1 in accordance with the principles of the present invention.
  • [0033]
    FIG. 5 illustrates a perspective view of one embodiment of a plurality of individual core pieces of FIG. 4 attached to a reference block to form a multicore bar in the process of forming a timing-based servo verify head of FIG. 1 in accordance with the principles of the present invention.
  • [0034]
    FIG. 6 illustrates a perspective view of one embodiment of a modified multicore bar having portions of core pieces removed to define outwardly extending magnetic elements and read gap tolerances in accordance with the principles of the present invention.
  • [0035]
    FIG. 7 illustrates a partially enlarged view of one of the core bars of the multicore bar of FIG. 6 in accordance with the principles of the present invention.
  • [0036]
    FIG. 8 illustrates a perspective view of a slider element with a plurality of slots bonded with the modified multicore bar of FIG. 6 in accordance with the principles of the present invention.
  • [0037]
    FIG. 8 a illustrates a backside of the perspective view of FIG. 8.
  • [0038]
    FIG. 9 illustrates a perspective view of a structure having portions of the slider element and multicore bar of FIG. 8 removed to form the first half-slider of a magnetic head in accordance with the principles of the present invention.
  • [0039]
    FIG. 9 a illustrates a top down view of the structure of FIG. 9.
  • [0040]
    FIG. 10 illustrates a perspective view of one embodiment of the first half of the servo verify head, having a support beam attached, in accordance with the principles of the present invention.
  • [0041]
    FIG. 11 illustrates a perspective view of one embodiment of a servo verify head where the second half of the servo verify head is bonded to the first half of the servo verify head in accordance with the principles of the present invention.
  • [0042]
    FIG. 12 illustrates a top view of one embodiment of the servo verify head of FIG. 11.
  • [0043]
    FIG. 13 illustrates a second embodiment of a timing-based servo verify head in accordance with the principles of the present invention.
  • [0044]
    FIG. 14 illustrates a flow chart of a second exemplary process of forming the second embodiment of the timing-based servo verify head of FIG. 13 in accordance with the principles of the present invention.
  • [0045]
    FIG. 15 illustrates a perspective view of one embodiment of a core bar in the process of forming the second embodiment of the timing-based servo verify head of FIG. 13 in accordance with the principles of the present invention.
  • [0046]
    FIG. 16 illustrates a perspective view of one embodiment of the core bar having portions of core pieces removed to define outwardly extending magnetic elements and read gap tolerances in accordance with the principles of the present invention.
  • [0047]
    FIG. 17 illustrates a top view of the one embodiment of the core bar shown in FIG. 16.
  • [0048]
    FIG. 18 illustrates a perspective view of a slider element with a plurality of slots for mating with the core bar of FIG. 16 in accordance with the principles of the present invention.
  • [0049]
    FIG. 19 illustrates a perspective view of a structure having portions of the slider element and core bar of FIG. 18 removed to form the first half of the servo verify head in accordance with the principles of the present invention.
  • [0050]
    FIG. 20 illustrates a top view of the structure shown in FIG. 19.
  • [0051]
    FIG. 21 illustrates an exploded view of one embodiment of the servo verify head shown in FIG. 13 where the second half of the servo verify head is to be bonded to the first half of the servo verify head in accordance with the principles of the present invention.
  • [0052]
    FIG. 22 illustrates a bottom view of the embodiment of the servo verify head after a plurality of magnetic u-cores are attached to the magnetic structure of the servo verify head.
  • [0053]
    FIG. 23 illustrates a top view of one embodiment of a servo verify head having a core bar that uses a thin film head row bar in accordance with the principles of the present invention.
  • [0054]
    FIG. 24 illustrates an exploded view of the embodiment of the servo verify head having the core bar that uses the thin film head row bar of FIG. 23.
  • [0055]
    FIG. 25 illustrates a perspective view of a third embodiment of a timing-based servo verify head using scanning head technique in accordance with the principles of the present invention.
  • [0056]
    FIG. 26 illustrates a perspective view of one embodiment of a core bar as shown in FIGS. 3 and 15 having portions of core pieces removed to define outwardly extending magnetic elements and read gap tolerances in accordance with the principles of the present invention.
  • [0057]
    FIG. 27 illustrates a top view with a slanted angle of the embodiment of the core bar shown in FIG. 26.
  • [0058]
    FIG. 28 illustrates a partially enlarged view of the embodiment of the core bar shown in FIG. 26.
  • [0059]
    FIG. 29 illustrates a perspective view of a slider element with a plurality of slots for mating with the core bar of FIG. 26 in accordance with the principles of the present invention.
  • [0060]
    FIG. 30 illustrates a perspective view of the embodiment of the servo verify head shown in FIGS. 25-29 after a plurality of magnetic u-cores are attached to the magnetic structure of the servo verify head.
  • DETAILED DESCRIPTION
  • [0061]
    The present invention relates to heads for use with magnetic tape, and methods for forming heads. Various embodiments of the present invention are described herein.
  • [0062]
    FIG. 1 shows a head 10 having five channels 12 with each channel having a first magnetic structure (first gap) 56 a and a second magnetic structure (second gap) 56 b. As shown in FIG. 1, each of the first magnetic structures 56 a are parallel but not collinear and each of the second magnetic structures 56 b are parallel but not collinear. As shown in FIG. 1, the first magnetic structures are −6 degrees from a x-axis, and the second magnetic structures are +6 degrees from a x-axis. Also, in head 10, each magnetic structure is magnetically and electrically independent. The head as shown in FIG. 1 may be used to verify a TBS pattern written to a tape. In use, the head shown in FIG. 1 has a surface contour that provides a good or acceptable head to tape interface.
  • [0063]
    With reference to FIGS. 2-12, a technique to manufacture heads having magnetic structures that include angles will be described. The process to be described enables the manufacture of any single magnetic line pattern that can be mechanically diced and reassembled to have mechanically and electrically independent channels with the line having any angle. Moreover, as will be made clear by the manufacturing process, the resulting head may have magnetic structures in each of the channels that are not parallel or collinear to each other. Alternatively, the heads may be manufactured to provide parallel and/or collinear relationships between the magnetic structures in one or more of the channels. Also, the process provides for a high degree of precision (e.g., within a micron or two).
  • [0064]
    FIG. 2 illustrates one example of the operations for forming a magnetic tape head with discrete and independent magnetic elements, in accordance with one embodiment of the present invention. This process can be utilized to form a magnetic tape head as shown in the example of FIG. 1 or other tape heads having two or more discrete and independent magnetic elements aligned in a precise manner.
  • [0065]
    The operations of FIG. 2 may be used to form a magnetic head without having to bond or connect in multiple operations the plurality of magnetic servo elements to portions of the magnetic head. The operations of FIG. 2 provide for precise alignments of the plurality of individual core pieces to form a magnetic head using these operations. Accordingly, the operations of FIG. 2 can be used to form a magnetic head having typical or standard head geometries, without the need for the manufacturing process having to include multiple alignment operations of each magnetic element to one another. Hence, the operations of FIG. 2 may be used to form a head with a typical or standard head to tape interface.
  • [0066]
    In one example, an azimuth head having a plurality of independent and aligned magnetic structure is generally formed by creating a first half of the head and a second half of the head, then attaching the first half with the second half with a spacer portion therebetween. Operations 20-34 of FIG. 2 may be used to form the halves of the head structures, and operation 36 assembles the halves to form the final head structure, in one example.
  • [0067]
    At operation 20, a magnetic ferrite gap bar, or core bar, is formed with one or more magnetic gaps or cavities defined between at least two types of magnetic materials. One example of a core bar 50 is shown in FIG. 3. In one example, the core bar may be a generally elongated, rectangular structure, having a first portion 52, a second portion 54, and a magnetic read/write gap 56. The first portion of the core bar may be generally rectangular and include an interface (gap) surface for attachment to the second portion of the core bar. The second portion of the core bar may be a generally elongated, rectangular structure having two or more slots 58 and 60 extending linearly along the length of the second portion. The slot 58 will be used to wind wire to energize the magnetic structure. The slot 60 exists to define the height of the magnetic core when full processing is completed. The first and second portions are bonded together using conventional glass bonding or other conventional bonding techniques. The faces of portions 52 and 54 where they are joined typically contain a thin nonmagnetic spacing material. This spacing material, typically 0.3 μm to a few μm thick, results in the magnetic read/write gap 56.
  • [0068]
    In one example, the first 52 and second 54 portions of the core bar may be made from magnetic ceramic materials such as NiZn Ferrite.
  • [0069]
    At operation 22, the core bar 50 may be divided or diced into multiple individual azimuth core pieces 62. One example of an individual core piece is shown in FIG. 4. In one example, the core bar is diced into individual azimuth core pieces at an angle of +6° or −6° to the gap 56. These cores are then squared or made orthogonal to the diced face 64, resulting in an orthogonal cross-section with the angled gap 56.
  • [0070]
    At operation 24, FIG. 5, two or more core pieces 62 are attached to a reference block 72 to form an azimuthal multicore bar 70, each core piece being accurately positioned relative to one another on the reference block. In one example, the reference block 72 is a generally elongated L-shaped structure defining a shelf portion upon which the core pieces are positioned. The reference block 72 may be made from any suitable material which maintains dimensional stability. In one example, the reference block 72 is made from BaTiO for a stable material matched with the magnetic ceramic 52 and 54 for thermal expansion characteristics. In this operation, the parallelism of the gaps 56, the co-planarity of the cores surfaces of 62, and the distance between the cores is governed by the desired final head design requirements. In one example, a bonding tool or fixture is used to position and reference the core pieces on the reference block. This bonding tool references each core independently and maintains the core independently referenced in five degrees of freedom. The sixth degree of freedom is also constrained, but not independently for each core. In this dimension, the core references are coupled. Once the cores are thus positioned, they are bonded to the reference block to accurately secure their relative positions for further processing. The bonding fixture allows the cores to be either epoxy bonded or glass bonded to the reference block, with a possible temperature range of 50-750° F., while maintaining the multidimensional reference. FIG. 5 is one example of an azimuthal multicore bar 70, showing five cores or core pieces 62.
  • [0071]
    Operation 26, FIGS. 6 and 7, modifies the azimuthal multicore bar 70. In one example, operation 26 removes portions of the core pieces 62 from the azimuthal multicore bar, which may be accomplished by machining portions of the core pieces to form T-shaped magnetic elements outwardly extending from the reference block. Cuts 74 and 76 are precision machined surfaces. These surfaces define the width of the magnetic read gap 56. This approach, machining the read gap width and position of all azimuth cores 62 in a single operation, allows precise location and pitch of the read gaps 56 relative to each other. The precision of this approach is greater than that can be achieved by machining the cores individually and then assembling them. In one example, the width of the magnetic read gap 56 is approximately 200 μm, and the pitch between any two adjacent cores is 2.858 mm with a precision of around 1 μm.
  • [0072]
    At operation 28, FIGS. 8 and 8 a, a slider element 92 is bonded to the modified azimuth multi-core bar 80 to form a bonded slider bar 90. In one example, the slider 92 is an elongated, generally rectangular structure having a machined slot 96 extending along its length, and having a plurality of partial slots 94 orthogonally oriented relative to the elongated slot. Each partial slot 94 is adapted to receive the T-shaped magnetic elements extending from the modified multi-core bar 80 of operation 26. Machined slot 96 allows access to slot 58 for winding wire onto the individual cores. The slider 92 will serve as the tape bearing surface of the magnetic head. The slider 92 may be bonded onto the modified azimuthal bar 80 by conventional techniques of epoxy or glass bonding, and may be made from any suitable non magnetic material. In one example, the slider 92 is formed from a nonmagnetic BaTiO ceramic for thermal expansion and tape wear characteristics.
  • [0073]
    At operation 30, FIG. 9, the bonded slider bar 90 is machined to form a half-slider 100. In one example, portions of the slider element, core bar, and core pieces are removed to form a first or second half of the magnetic head. For example, the top surface may be processed to expose the individual magnetic structures 62 containing azimuth recording gaps 56. A portion of the L-shaped reference block 72 (FIG. 6) may be removed along with the remaining stock on the bottom of the bar to achieve, for example, a series of five individual separated magnetic cores 62. Each core contains a magnetic structure at an angle to the orthogonal surfaces of the bar. FIG. 9 a shows a top down view of the half-slider 100.
  • [0074]
    At operation 32, FIG. 10, a support beam 112 is bonded to the bottom of the half-slider 100 to form a half-head 110. In one example, the support beam 112 is formed from a nonmagnetic BaTiO ceramic for a materials match to ferrite.
  • [0075]
    At operation 34, operations 20-32 are repeated to form the other half-head 110 for use in making the magnetic head 10. For instance, operations 20-32 may be used to form the first half-head 110 with an azimuth angle of +6° and the second half-head 110 with an azimuth angle of −6°.
  • [0076]
    At operation 36, FIGS. 11 and 12, the first and second half-heads 110 are assembled to form the magnetic head 120. In one example, the first and second halves are bonded to a spacer element 122. The spacer element 122 may be any suitable nonmagnetic material to provide isolation between the two halves of the head 120. In one example, two thin sheets of copper 124 are bonded on either side of the spacer element 122 to provide electrical noise isolation between the two halves of the head. In one example, the spacer material 122 is a nonmagnetic BaTiO ceramic, chosen for tape wear characteristics. In one example, the first and second halves 110 are bonded together, where the angle of the magnetic structures on one bar are different than those on the other. If desired, contours to customize head to tape interfaces may now be machined on the surface to produce a final device.
  • [0077]
    One example of a magnetic head formed by the operations of FIG. 2 is shown in FIGS. 1 and 11-12, where FIG. 12 shows a top view of the head face. In one example, the first magnetic gaps 56A and second magnetic gaps 56B are at +6 and −6° respectively. This full head 10 or 120, may be utilized to verify a TBS pattern on a magnetic tape, where each servo pattern and each angle of any servo pattern may be independently verified. Independent verification allows greater flexibility and accuracy of the servo pattern on tape. In addition, the process described above, resulting in gaps that are parallel but not collinear and hence limiting the overall size of the servo head, allows for a standard cylindrical contour to be machined onto the head face to provide a good and acceptable head to tape interface.
  • [0078]
    If desired, the process of FIG. 2 can be utilized with any combination of ferrite or thin film head element, which may include inductive, AMR or GMR.
  • [0079]
    FIG. 13 illustrates another example of a magnetic head 140 having a plurality of magnetically and electrically independent magnetic elements 144 which may be used, in one example, for reading servo patterns on a magnetic tape. In FIG. 13, the magnetic head includes a first set of magnetic elements and a second set of magnetic elements, wherein the first set of magnetic gaps 162 a and the second set of magnetic gaps 162 b are disposed to one another along an angle defined by a center spacing element 148. A pair of wedge-shaped outriggers 146 can be used to provide a generally rectangular structure to the head, and the center spacer or center spacing element 148 can be utilized to set the respective angles of the magnetic read gaps 162 a and 162 b. In one example, each set of magnetic read gaps 162 a and 162 b are parallel and collinear.
  • [0080]
    FIG. 14 illustrates an example of operations that may be used to form a magnetic head, such as the head shown in FIG. 13. The operations of FIG. 14 may be utilized to form a magnetic head of, in one example, a non-standard size or a non-standard head to tape interface.
  • [0081]
    At operation 50, FIG. 15, a core bar 160 is formed with one or more magnetic gaps 162. The core bar 160 may have the same or similar characteristics as the core bar 50 as described above in FIG. 3 or as produced by operation 20 in FIG. 2. Any suitable gap bar, such as a ferrite gap bar 160 or magnetic head row bar, such as a section of a thin film head wafer that is diced into a row of thin film heads forming a thin film head row bar, may be used as the core bar.
  • [0082]
    At operation 52, FIGS. 16 and 17, a multi-core bar 170 is formed by processing or machining the core bar 160 to have a plurality of upwardly extending magnetic elements 172. In one example, five upwardly extending magnetic elements 172 are provided, wherein each of the upwardly extending portions includes at least one magnetic gap 162. In one example, the upwardly extending portions are rectangularly shaped with their long axis at an azimuth angle of +6° with respect to the long axis of the multi-core bar 170. In one example, the multi-core bar edge face 174 is machined at an azimuth angle of +6° with respect to the long axis of the multi-core bar 170. This angled structure can be seen most clearly in FIG. 17. The core bar 170 may have similar tolerance characteristics as the core bar 80 of FIG. 6 made in operation 26.
  • [0083]
    At operation 54, FIG. 18, a slider element 192 with a plurality of slots 194 for mating with the extending magnetic elements 172, is attached to the multi-core bar 170 of operation 52. The slider element 192 will serve as the tape bearing surface and may be made from any suitable nonmagnetic and nonconductive material. In one example, a BaTiO ceramic is used for its tape wear characteristics and its match to the mechanical properties of ferrite. The slider element 192 may be bonded to the core bar 170 by any suitable means, including epoxy or glass bonding, to produce a bonded slider 190. In one example, the ends 196 of the slider element 192 may be machined at an angle of +6° to the long axis of the slider element 192.
  • [0084]
    The bonded slider element 190 of operation 54 may have the same or similar characteristics as described above with reference to operation 28 of FIG. 2 or FIG. 8.
  • [0085]
    At operation 58, FIGS. 19 and 20, the structure of operation 54 is processed to form a first half-head magnetic head structure 200. In one example, the structure 200 is machined on the top surface to expose the magnetic structures 172 and the magnetic sensing gaps 162. The remaining stock on the bottom of the core bar 170 is also removed to achieve a series of five individual magnetic structures or cores 172 separated by the remaining slider element 192. In one example, the long axis faces 202, 204 of the half-head 200 are machined orthogonal to the magnetic gaps 162, as can be seen most clearly in FIG. 20.
  • [0086]
    At operation 60, the operations 50-58 are repeated to form a second magnetic half-head.
  • [0087]
    At operation 62, FIGS. 21 and 13, first and second half-heads 200 are assembled to form the magnetic head 140. FIG. 21 is an exploded view of FIG. 13 for illustrative purposes. In one example, the first and second half-heads 200 formed by operations 50-60 may be attached to the wedge-shaped center spacer element 148, as shown in FIGS. 21 and 13. Further, a pair of wedge-shaped elements or outriggers 146 can be attached to the outer portions of the first and second magnetic half-heads to form the generally rectangular final head 140 as shown in FIG. 13.
  • [0088]
    The angles of the magnetic structures 172 containing the magnetic sensing gaps 162 may be set by the angles machined into the center spacer 148, or may be free-space aligned. Complimentary angles may be machined into the outriggers 146 so the final head geometry is rectangular, which may provide greater tape dynamic stability when compared with nonrectangular cross-section head geometries. The center spacer 148 and the outriggers 146 may be formed from any suitable nonmagnetic and electrically insulating material. In one example, both 148 and 146 are made from a BaTiO ceramic, chosen for its tape wear characteristics. The head 140, shown in an exploded view in FIG. 21, may be bonded together by any appropriate means, including either epoxy or glass bonding.
  • [0089]
    In FIG. 22, the bottom of the servo verify head 140 is shown where magnetic u-cores 222 have been attached to the magnetic structures 172. These u-cores 222 may be wound with wire to complete the magnetic circuit. In one example, these u-core are made from a magnetic NiZn ferrite. FIGS. 13 and 22 represent the completed TBS verify head 220.
  • [0090]
    The operations of FIG. 14 may be used to reduce the complexity in manufacture of a TBS verify head, as the contour allows for the magnetic read gaps to be parallel and collinear. The operations of FIG. 14 do not require the assembly of individual azimuth cores while maintaining multidimensional tolerances. In addition, the tolerances between and of the individual magnetic structures can be more tightly constrained. The processes of FIGS. 2 and 14 and the device resulting thereof may also be used for the production of a Servo Write head, or any relevant magnetic recording read or write head used in Timing Based Servo.
  • [0091]
    As an additional example of this method, shown in FIGS. 23-24, is a head having a core bar that uses a thin film head row bar 232 a, 232 b instead of a ferrite half-head bar 200. In one example, two thin film row bars, 232 a and 232 b, are combined with a center spacer 148 and two outriggers 146 to form the final head 230. The angles of the magnetic structures may be set by the angles machined into the center spacer 148, or may be free-space aligned. Complimentary angles may be machined into the outriggers 146 so the final head geometry is rectangular, in one example.
  • [0092]
    FIG. 23 shows a top view of the magnetic head 230, while FIG. 24 shows an exploded view of head 230 made according to one example of the present invention. The final contour may be a flat face. The center spacer 148 and the outriggers 146 may be made from any appropriate nonmagnetic material. In one example, elements 146 and 148 are made from an AlTiC ceramic, for tape wear characteristics and material match to the thin film row bar substrate.
  • [0093]
    This process and device may also be used for the production of a servo write head, or any relevant magnetic recording read or write head used in Timing Based Servo. The thin film row bar may contain any reasonable thin film head, which may include inductive, AMR or GMR elements.
  • [0094]
    The processes of FIGS. 2 and 14 described previously are for a full-band servo verification head for TBS servo patterns. The azimuth angle of the magnetic structures is used to align the magnetic sensor on the servo verify head to the azimuth angle of the recorded servo pattern on the media. As an alternative to this approach, the verify magnetic read gap may be restricted to a width much less than the servo track width. As previously discussed, such a structure may not suffer from azimuth alignment loss of the sensed signal as the angle is effectively zero over such small track widths. A verify head constructed as such, a so called partial-band verify, would then be mechanically scanned along the width of the pattern to be verified. Such a head, constructed of independent read elements could be fabricated as a straight row bar or gap bar, i.e. without the azimuth angle. In addition, such a head would only require one magnetic sensing gap, rather than a separate gap for each pattern angle. This head could be constructed from any combination of ferrite or thin film head element, which may include inductive, AMR or GMR.
  • [0095]
    FIG. 25 represents one embodiment of a servo verify head 250 using a scanning head technique wherein the magnetic servo verify head 250 includes five independent magnetic elements 252 interlaced between six ceramic slider elements 254. The servo verify head 250 may be formed by processing techniques similar in style to those of FIGS. 2 and 14 previously described, with the exception that all processing is performed in an orthogonal system. i.e. there are no azimuth angles machined into the head.
  • [0096]
    In one example, as with the embodiments described in the full-band servo verify heads, a ferrite gap bar which may be similar to those of FIG. 3 or 15 is processed to form a multi-core bar 260, FIGS. 26-28. In one embodiment, material is removed leaving magnetic structures 252 with magnetic gaps 262. In one embodiment, slots 264 and 266 are processed on the top of the magnetic structures 252 producing the magnetic read gap 262 with a width of approximately 10 μm. The orthogonal processing can be seen most clearly in FIG. 27, where the magnetic structures 252 are orthogonal to the long axis of the ferrite gap bar. The slots 264 and 266, used to define the read sensor gap 262 width, can be seen most clearly in FIG. 28. In one example, FIG. 26 is similar in style to FIGS. 6 and 16.
  • [0097]
    As described in the processes of FIGS. 2 and 14, a mating slider is attached to the multi-core bar 260. FIG. 29 shows one embodiment of this process. A slider 292, comprising five complimentary slots 294 is mated to the multi-core bar 260 producing the bonded slider 290. The slider 292 may be attached using any appropriate technique such as glass or epoxy bonding, and may be made from any suitable nonmagnetic material. In one embodiment, the slider element 292 is made from BaTiO ceramic, chosen for its tape wear characteristics and materials match to the ferrite multi-core bar 260. The bonded slider 290 may be processed similar to operations 30 and 58, FIGS. 9 and 19 respectively, to produce the magnetic servo head 250 of FIG. 25.
  • [0098]
    FIG. 30 shows one embodiment of the partial-verify, or scanning servo verify head 300. The magnetic head 300 has been processed to create a cylindrical contour on the surface to obtain a good or acceptable head to tape interface. In addition, u-cores 302 have been attached to the bottom of the head 300. Wire may be wound on the u-cores 302 to complete the magnetic sensing circuit.
  • [0099]
    As previously described, the partial-verify head 300 may be scanned along the width of a TBS servo pattern. In one example, a TBS pattern with a width of 190 μm at an azimuth angle of 6° can be verified by a read sensor with a width of 5-10 μm at an azimuth angle of 0°, the head 300 being continuously scanned back and forth along the 190 μm track width of the servo band. In this example, the partial-verify head may sense any particular 10 μm segment of the 190 μm track width. In one example, the head 300 possesses at least one magnetic sensing element per servo band to be verified, such that all servo patterns spanning the tape may be partial-verified in a single pass of the media. This head could be constructed from any combination of ferrite or thin film head element, including inductive, AMR or GMR.
  • [0100]
    As previously mentioned, a factor of the scanning or partial-verify method is the scan rate. The scan rate represents the fraction of any servo band width sampled. One means of reducing this factor is to reduce the scan rate. This may be accomplished by a partial-verify head with more than one sensing gap per servo band. In one example, a partial-verify head has five independent sensing regions, each sensing region comprising two or more sensing gaps.
  • [0101]
    In one example, two sensing gaps, each 10 μm in width, are spaced 100 μm apart from center to center. In this example, a servo pattern with a 190 μm track width may be scanned in approximately half the time as compared to the embodiment of FIG. 30, as each sensing gap would have to traverse only half the pattern. The use of multiple sensing gaps for each servo band may significantly reduce the scan rate of the partial-verify method, correspondingly increasing the defect detection efficiency. This head could be constructed from any combination of ferrite or thin film head element, which may include inductive, AMR or GMR.
  • [0102]
    One example of a TBS system currently used in industry is the so-called Linear Tape Open (“LTO”) system. LTO utilizes a series of five servo bands to span the tape in the cross-track direction. The embodiments of a TBS verify magnetic head described herein may allow all servo bands to be simultaneously and independently verified. Such a quality is valuable in the production environment as it combines both efficiency and accuracy.
  • [0103]
    While the methods disclosed herein have been described and shown with reference to particular operations performed in a particular order, it will be understood that these operations may be combined, sub-divided, or re-ordered to form equivalent methods without departing from the teachings of the present invention. Accordingly, unless specifically indicated herein, the order and grouping of the operations is not a limitation of the present invention.
  • [0104]
    Although the present invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Claims (21)

  1. 1-39. (canceled)
  2. 40. A servo head capable of writing a portion of a timing based pattern comprising at least two magnetic writing gap elements, wherein the at least two magnetic writing gap elements are parallel and co-linear.
  3. 41. The servo head of claim 40, wherein the at least two magnetic writing gap elements are substantially aligned to a predetermined angle with respect to the direction of a magnetic media velocity.
  4. 42. The servo head of claim 40, wherein the servo head further comprises at least one thin film head row bar comprising the at least two magnetic writing gap elements.
  5. 43. The servo head of claim 40, wherein the servo head further comprises at least one magnetic gap bar comprising the at least two magnetic writing gap elements.
  6. 44. The servo head of claim 40, wherein the servo head comprises a plurality of magnetic writing gap elements.
  7. 45. The servo head of claim 40, further comprising at least one additional gap element, wherein the at least two magnetic writing gap elements are substantially aligned to a predetermined angle with the at least one additional gap element.
  8. 46. The servo head of claim 40, wherein the timing of energizing the at least two magnetic writing gap elements is staggered to produce an arbitrary pattern of magnetic transitions on magnetic media.
  9. 47. The servo head of claim 45, wherein the timing of energizing the gap elements is staggered to produce an arbitrary pattern of magnetic transitions on magnetic media.
  10. 48. A servo head capable of writing a portion of a timing based pattern comprising at least two magnetic writing gap elements, wherein the at least two magnetic writing gap elements are parallel and not co-linear.
  11. 49. The servo head of claim 48, wherein the at least two magnetic writing gap elements are substantially aligned to a predetermined angle with respect to the direction of a magnetic media velocity.
  12. 50. The servo head of claim 48, wherein the servo head further comprises a thin film head row bar comprising the at least two magnetic writing gap elements.
  13. 51. The servo head of claim 48, wherein the servo head further comprises a magnetic gap bar comprising the at least two magnetic writing gap elements.
  14. 52. The servo head of claim 48, wherein the servo head comprises a plurality of magnetic writing gap elements.
  15. 53. The servo head of claim 48, further comprising at least one additional gap element, wherein the at least two magnetic writing gap elements are substantially aligned to a predetermined angle with the at least one additional gap element.
  16. 54. The servo head of claim 48, wherein the timing of energizing the at least two magnetic writing gap elements is staggered to produce an arbitrary pattern of magnetic transitions on magnetic media.
  17. 55. The servo head of claim 53, wherein the timing of energizing the gap elements is staggered to produce an arbitrary pattern of magnetic transitions on magnetic media.
  18. 56. Magnetic media made with a servo head capable of writing a portion of a timing based pattern comprising at least two magnetic writing gap elements, wherein the at least two magnetic writing gap elements are parallel and co-linear.
  19. 57. The magnetic media of claim 56, wherein the magnetic media is magnetic tape.
  20. 58. Magnetic media made with a servo head capable of writing a portion of a timing based pattern comprising at least two magnetic writing gap elements, wherein the at least two magnetic writing gap elements are parallel and not co-linear.
  21. 59. The magnetic media of claim 58, wherein the magnetic media is magnetic tape.
US11693489 2003-12-19 2007-03-29 Timing-based servo verify head and method thereof Abandoned US20070230040A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US53094303 true 2003-12-19 2003-12-19
US11017529 US8144424B2 (en) 2003-12-19 2004-12-20 Timing-based servo verify head and magnetic media made therewith
US11693489 US20070230040A1 (en) 2003-12-19 2007-03-29 Timing-based servo verify head and method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US11693489 US20070230040A1 (en) 2003-12-19 2007-03-29 Timing-based servo verify head and method thereof

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US11017529 Continuation US8144424B2 (en) 2003-12-19 2004-12-20 Timing-based servo verify head and magnetic media made therewith

Publications (1)

Publication Number Publication Date
US20070230040A1 true true US20070230040A1 (en) 2007-10-04

Family

ID=34752398

Family Applications (2)

Application Number Title Priority Date Filing Date
US11017529 Expired - Fee Related US8144424B2 (en) 2003-12-19 2004-12-20 Timing-based servo verify head and magnetic media made therewith
US11693489 Abandoned US20070230040A1 (en) 2003-12-19 2007-03-29 Timing-based servo verify head and method thereof

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US11017529 Expired - Fee Related US8144424B2 (en) 2003-12-19 2004-12-20 Timing-based servo verify head and magnetic media made therewith

Country Status (1)

Country Link
US (2) US8144424B2 (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130286506A1 (en) * 2012-04-26 2013-10-31 Imation Corp. Servo write head
US8760802B2 (en) 2012-04-26 2014-06-24 Imation Corp. Systems and methods for processing magnetic media with first and second magnetic gaps adjacent opposite sides of the recording layer
US8767342B2 (en) 2011-06-13 2014-07-01 Imation Corp. Erasure and servowriting of magnetic storage media having perpendicular anistropy
US8797674B2 (en) 2011-06-13 2014-08-05 Imation Corp. Servo mark length matched to write head gap for magnetic storage media
US8804276B2 (en) 2011-06-13 2014-08-12 Imation Corp. Continuous biasing and servowriting of magnetic storage media having perpendicular anisotropy
US8817415B2 (en) 2011-06-13 2014-08-26 Imation Corp. Erasure of magnetic storage media having perpendicular anisotropy
US8867157B2 (en) 2012-04-04 2014-10-21 Imation Corp. Perpendicular pole head for servo writing magnetic media
US8867167B2 (en) 2012-04-26 2014-10-21 Imation Corp. Tapered pole heads for magnetic media
US8947802B2 (en) 2012-04-26 2015-02-03 Imation Corp. Methods and systems for magnetic media servo writing

Families Citing this family (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7199957B2 (en) * 2004-03-30 2007-04-03 Imation Corp. Write head alignment for full amplitude time-based servo
US8767331B2 (en) 2009-07-31 2014-07-01 Advanced Research Corporation Erase drive system and methods of erasure for tape data cartridge
US9129614B2 (en) * 2013-05-01 2015-09-08 International Business Machines Corporation Magnetic head having canted arrays
US9208809B2 (en) 2013-05-01 2015-12-08 International Business Machines Corporation Magnetic head and system having offset arrays
US9449628B2 (en) 2013-05-01 2016-09-20 International Business Machines Corporation Quasi-statically oriented, bi-directional tape recording head
US8810957B1 (en) 2013-09-05 2014-08-19 International Business Machines Corporation Quasi-statically tilted head having dilated transducer pitch
US9214164B2 (en) 2013-09-16 2015-12-15 International Business Machines Corporation Miniskirt tape head having quasi-statically tilted transducer arrays
US9135935B1 (en) 2013-10-11 2015-09-15 Western Digital Technologies, Inc. Customized head gimbal assembly bonding skew angle for adjusting two-dimensional magnetic recording reader alignment
US9042058B1 (en) 2013-10-17 2015-05-26 Western Digital Technologies, Inc. Shield designed for middle shields in a multiple sensor array
US8988812B1 (en) 2013-11-27 2015-03-24 Western Digital (Fremont), Llc Multi-sensor array configuration for a two-dimensional magnetic recording (TDMR) operation
US9218838B2 (en) 2013-12-12 2015-12-22 International Business Machines Corporation Quasi-statically tilted head having offset reader/writer transducer pairs
US9007712B1 (en) 2013-12-16 2015-04-14 International Business Machines Corporation Backward compatible head for quasi-static tilted reading and/or recording
US8970988B1 (en) 2013-12-31 2015-03-03 Western Digital (Fremont), Llc Electric gaps and method for making electric gaps for multiple sensor arrays
US9653098B2 (en) * 2014-01-16 2017-05-16 Oracle International Corporation Tape head modules for performing azimuth recording and reading of tape media using a linear format
US9245556B2 (en) 2014-03-10 2016-01-26 Western Digital Technologies, Inc. Disk drive employing multiple read elements to increase radial band for two-dimensional magnetic recording
US9070406B1 (en) 2014-03-10 2015-06-30 Western Digital Technologies, Inc. Disk drive configuring one-dimensional and two-dimensional recording areas based on read element spacing
US9053727B1 (en) 2014-06-02 2015-06-09 Western Digital Technologies, Inc. Disk drive opening spiral crossing window based on DC and AC spiral track error
US9013824B1 (en) 2014-06-04 2015-04-21 Western Digital Technologies, Inc. Data storage device comprising dual read sensors and dual servo channels to improve servo demodulation
US9117470B1 (en) 2014-07-17 2015-08-25 International Business Machines Corporation Write delay to de-skew data in read while write function for tape storage devices
US9934804B1 (en) 2016-09-22 2018-04-03 International Business Machines Corporation Segmented magnetic recording write head for detection-based servo pattern writing
US9852747B1 (en) 2016-09-22 2017-12-26 International Business Machines Corporation Segmented magnetic recording write head for writing timing-based servo patterns
US9892751B1 (en) 2016-10-27 2018-02-13 International Business Machines Corporation Achieving fine motion between modules in a magnetic head
US9947354B1 (en) 2017-03-20 2018-04-17 International Business Machines Corporation Utilization of multiple writer modules for simultaneously writing two times the number of data tracks in a compact form factor

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5321570A (en) * 1989-10-02 1994-06-14 Behr Michael I Systems using superimposed, orthogonal buried servo signals
US5523904A (en) * 1992-06-24 1996-06-04 Quantum Corporation Linear tape write servo using embedded azimuth servo blocks
US5572392A (en) * 1994-11-17 1996-11-05 International Business Machines Corporation Arbitrary pattern write head assembly for writing timing-based servo patterns on magnetic storage media
US20030151844A1 (en) * 2002-02-13 2003-08-14 International Business Machines Corporation Timing based servo with fixed distances between transitions
US20060126207A1 (en) * 2004-06-02 2006-06-15 Imation Corp. Dual mode servo pattern
US7072133B1 (en) * 2001-10-15 2006-07-04 Imation Corp. Servo mark verify head

Family Cites Families (204)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2938962A (en) 1955-07-12 1960-05-31 Konins Azimuth seeking reproducing head
US3192608A (en) 1960-07-26 1965-07-06 Philips Corp Multiple ferrite heads with workable metal screens
US3417386A (en) 1965-10-11 1968-12-17 Cons Electrodynamics Corp Magnetic head assembly
US3699334A (en) 1969-06-16 1972-10-17 Kollsman Instr Corp Apparatus using a beam of positive ions for controlled erosion of surfaces
US3750828A (en) 1969-08-25 1973-08-07 Smiths Industries Ltd Access-control equipment and item dispensing systems including such equipment
US3853715A (en) 1973-12-20 1974-12-10 Ibm Elimination of undercut in an anodically active metal during chemical etching
US4007493A (en) 1975-05-06 1977-02-08 Burroughs Corporation Track positioning system for magnetic transducer head
US4088490A (en) 1976-06-14 1978-05-09 International Business Machines Corporation Single level masking process with two positive photoresist layers
US4314290A (en) 1977-06-16 1982-02-02 Burroughs Corporation Di-bit recording technique and associated servo indicia
JPS6124806B2 (en) 1978-03-03 1986-06-12 Matsushita Electric Ind Co Ltd
DE2912309A1 (en) 1978-03-28 1979-10-11 Olympus Optical Co Multiple magnetic tape recorder head construction - involves forming groove parts in core block with air gap as alternate thick and thin prongs
JPS54183322U (en) 1978-06-15 1979-12-26
JPS624769B2 (en) 1978-12-29 1987-01-31 Sony Corp
JPS5634128A (en) * 1979-08-23 1981-04-06 Rca Corp Multiple magnetic head for record*reproduction device
US4298899A (en) 1979-12-17 1981-11-03 International Business Machines Corporation Magnetic head assembly with ferrite core
US4539615A (en) * 1981-06-08 1985-09-03 Hitachi, Ltd. Azimuthal magnetic recording and reproducing apparatus
JPH0328017B2 (en) 1981-12-18 1991-04-17 Tokyo Shibaura Electric Co
US4488188A (en) 1982-11-01 1984-12-11 International Business Machines Corporation Buried servo recording system using phase encoded servo pattern
US4490756A (en) 1982-11-01 1984-12-25 International Business Machines Corporation Servo encodement and detection system using tetra-orthogonal servo pattern
US4609959A (en) 1982-11-29 1986-09-02 Tandberg Data A/S Device for positioning a magnetic head to various tracks of a magnetic tape
JPH0760490B2 (en) 1983-08-29 1995-06-28 ソニー株式会社 Method of manufacturing a multi-element thin-film magnetic heads
US4586094A (en) 1984-03-13 1986-04-29 Irwin Magnetic Systems, Inc. Method and apparatus for pre-recording tracking information on magnetic media
US4752850A (en) 1984-06-06 1988-06-21 Hitachi, Ltd. Multi-track magnetic thin film heads
NL8403595A (en) 1984-11-27 1986-06-16 Philips Nv A magnetic head having core parts of amorphous ferromagnetic metal.
JP2574744B2 (en) 1985-04-10 1997-01-22 株式会社日立製作所 Pcm signal recording and reproducing apparatus
US4598327A (en) 1985-06-28 1986-07-01 International Business Machines Corporation Servo control system using servo pattern time of flight for read/write head positioning in a magnetic recording system
US4642709A (en) 1985-10-16 1987-02-10 International Business Machines Corporation Twin track vertical magnetic recording servo control method
EP0233086B1 (en) * 1986-02-13 1992-01-29 Sony Corporation Thin film magnetic head
FR2604021B1 (en) 1986-09-17 1988-10-28 Commissariat Energie Atomique Process for producing magnetic heads of thin film and a planar structure and head obtained by this method
JPS63197011A (en) 1987-02-10 1988-08-15 Canon Electronics Inc Magnetic head core and its manufacture
US4758304A (en) 1987-03-20 1988-07-19 Mcneil John R Method and apparatus for ion etching and deposition
JPH0695367B2 (en) 1987-04-03 1994-11-24 松下電器産業株式会社 The magnetic head
US4945438A (en) * 1987-04-24 1990-07-31 Fuji Photo Film Co., Ltd. Combined magnetic head
NL8701667A (en) 1987-07-15 1989-02-01 Philips Nv Thin film magnetic transformer and provided with such a transformer.
US5035787A (en) 1987-07-22 1991-07-30 Microbeam, Inc. Method for repairing semiconductor masks and reticles
US5241442A (en) 1987-10-23 1993-08-31 Kabushiki Kaisha Toshiba Alignment disk
KR0126289B1 (en) 1988-02-09 1997-12-26 이우에 사또시 Magnetic head and method of manufacturing the same
US4906552A (en) 1988-02-22 1990-03-06 Hughes Aircraft Company Two layer dye photoresist process for sub-half micrometer resolution photolithography
FR2630244B1 (en) 1988-04-15 1990-07-13 Commissariat Energie Atomique Device for writing and reading on a magnetic medium and process for its manufacturing
FR2630853B1 (en) 1988-04-27 1995-06-02 Thomson Csf matrix device has magnetic heads in particular in thin layers
US4971947A (en) 1988-06-20 1990-11-20 University Of Colorado Foundation, Inc. Superconductor magnetic reading and writing heads
JPH0223506A (en) 1988-07-12 1990-01-25 Nec Corp Magnetic head
JP2569139B2 (en) 1988-08-24 1997-01-08 株式会社日立製作所 Ion beam processing method
DE68923247D1 (en) 1988-11-04 1995-08-03 Fujitsu Ltd A method of forming a resist pattern.
US5055951A (en) 1989-03-10 1991-10-08 Irwin Magnetic Systems, Inc. Method and apparatus for servo-positioning movable transducer heads
US5196969A (en) 1989-03-31 1993-03-23 Sharp Kabushiki Kaisha Head positioning system for serpentine magnetic recording/reproducing system
US5211734A (en) 1989-03-31 1993-05-18 Tdk Corporation Method for making a magnetic head having surface-reinforced glass
FR2648940B1 (en) 1989-06-27 1991-09-06 Thomson Csf head of realization of Method and magnetic multitrack multitrack magnetic head
US5016342A (en) 1989-06-30 1991-05-21 Ampex Corporation Method of manufacturing ultra small track width thin film transducers
US5189580A (en) 1989-06-30 1993-02-23 Ampex Corporation Ultra small track width thin film magnetic transducer
FR2649526B1 (en) 1989-07-04 1991-09-20 Thomson Csf Method of manufacturing magnetic heads by planar pocketed structure of a non-magnetic wafer, and magnetic heads obtained by such a process
FR2652669B1 (en) 1989-09-29 1992-11-20 Commissariat Energie Atomique Process for producing a magnetic recording head and head obtained by this method.
US5132861A (en) 1989-10-02 1992-07-21 Behr Michael I Systems using superimposed, orthogonal buried servo signals
US5017326A (en) 1989-10-05 1991-05-21 Eastman Kodak Company Film mid roll interrupt protection for a camera using magnetic azimuth recording on film
US5079663A (en) 1990-01-29 1992-01-07 International Business Machines Corporation Magnetoresistive sensor with track following capability
US5262908A (en) 1990-02-20 1993-11-16 Sharp Kabushiki Kaisha Tracking control device for magnetic recording/reproducing apparatus
FR2658646B1 (en) 1990-02-21 1995-07-13 Commissariat Energie Atomique A method of making a magnetic head has two magnetic materials, and head obtained by this method.
US5126231A (en) 1990-02-26 1992-06-30 Applied Materials, Inc. Process for multi-layer photoresist etching with minimal feature undercut and unchanging photoresist load during etch
US5402295A (en) 1990-04-16 1995-03-28 Hitachi, Ltd. Magnetic recording head capable of defining narrow track width and magnetic recording apparatus using the same
JPH0440613A (en) 1990-06-07 1992-02-12 Mitsubishi Electric Corp Thin film magnetic head element
DE4027194C2 (en) * 1990-08-28 1995-03-09 Tandberg Data Method and apparatus for positioning a magnetic head of a magnetic layer memory
US5160078A (en) 1991-02-12 1992-11-03 Storage Technology Corporation Rotating compliant tape guide
US5301418A (en) 1991-04-12 1994-04-12 U.S. Philips Corporation Method of manufacturing a magnetic head
US5280402A (en) 1991-08-30 1994-01-18 Minnesota Mining And Manufacturing Company Combined stepper motor and voice coil head positioning apparatus
EP0562093A1 (en) * 1991-10-10 1993-09-29 Eastman Kodak Company Tracking control apparatus including a servo head having a tapered transducing gap
US5319502A (en) 1992-01-10 1994-06-07 International Business Machines Corporation System and method for employing buried servos within a magnetic recording medium
JPH05281752A (en) 1992-03-31 1993-10-29 Seiko Instr Inc Processing method by convergent ion beam
DE69318617D1 (en) 1992-04-13 1998-06-25 Imation Corp A device for positioning head for multi-track tape recorder
US5307217A (en) 1992-06-24 1994-04-26 Digital Equipment Corporation Magnetic head for very high track density magnetic recording
US5371638A (en) 1992-06-24 1994-12-06 Digital Equipment Corporation Servo method and apparatus for very high track density magnetic recording by adjusting head position based on servo information read from adjacent track
JP2721783B2 (en) 1992-08-19 1998-03-04 インターナショナル・ビジネス・マシーンズ・コーポレイション The combination system and its manufacturing method of the thin film magnetic head transducer / suspension unit
US5309299A (en) 1992-10-07 1994-05-03 International Business Machines Corporation Method and system for position error signal generation using auto correlation
JP2943579B2 (en) 1992-10-20 1999-08-30 三菱電機株式会社 Magnetic structure and magnetic head and the magnetic recording head using the same
DE69424456D1 (en) 1993-03-02 2000-06-21 Sony Corp Magnetic head and process for its production
US5450257A (en) 1993-03-23 1995-09-12 Minnesota Mining And Manufacturing Company Head-tape alignment system and method
EP0625575A3 (en) 1993-04-30 1995-02-22 Lilly Co Eli Fem A gene of staphylococcus epidermidis, fem A protein, and vectors of microorganisms comprising the fem A gene.
JP2644182B2 (en) 1993-06-14 1997-08-25 インターナショナル・ビジネス・マシーンズ・コーポレイション Apparatus and method for initializing a multi-track magnetic tape apparatus
US5432652A (en) 1993-06-14 1995-07-11 International Business Machines Corporation Servo and data format for magnetic tape having plural spaced-apart servo areas interleaved with data track areas having serpentine track scanning using any one of a plurality of number of concurrently accessed tracks
GB9312831D0 (en) 1993-06-22 1993-08-04 Central Research Lab Ltd Method and apparatus for the determination of azimuth error
JP3312146B2 (en) 1993-06-25 2002-08-05 株式会社日立製作所 Magnetic head and manufacturing method thereof
DE4421517A1 (en) 1993-06-28 1995-01-05 Schlumberger Technologies Inc Method for removing or depositing material by means of a particle beam and device for carrying out the method
JPH0778309A (en) 1993-07-14 1995-03-20 Sony Corp Thin film magnetic head, magneto-resistance effect magnetic head and composite magnetic head
US5394285A (en) 1993-07-21 1995-02-28 Storage Technology Corporation Multi-track longitudinal, metal-in-gap head
US5423116A (en) 1993-07-21 1995-06-13 Storage Technology Corporation Method of manufacturing a multi-track longitudinal, metal-in-gap head
US5452166A (en) 1993-10-01 1995-09-19 Applied Magnetics Corporation Thin film magnetic recording head for minimizing undershoots and a method for manufacturing the same
JP3041174B2 (en) 1993-10-28 2000-05-15 株式会社東芝 Pattern correcting method in the pattern correction apparatus of the electron beam drawing apparatus
JPH07181672A (en) 1993-11-15 1995-07-21 Sanyo Electric Co Ltd Production of stencil mask
US5452165A (en) 1994-03-16 1995-09-19 International Business Machines Corporation Close packed magnetic head linear array
US5621188A (en) 1994-05-06 1997-04-15 Lee; Sang C. Air permeable electromagnetic shielding medium
US5689384A (en) 1994-06-30 1997-11-18 International Business Machines Corporation Timing based servo system for magnetic tape systems
FR2722024B1 (en) * 1994-07-01 1996-08-02 Thomson Consumer Electronics magnetic circuits for set of magnetic heads recording / playback
US5506737A (en) 1994-07-05 1996-04-09 Industrial Technology Research Institute High-density electronic head
US5488525A (en) 1994-08-18 1996-01-30 International Business Machines Corporation Decoupled magnetic head assembly for quarter-inch tape
US5909346A (en) 1994-08-26 1999-06-01 Aiwa Research & Development, Inc. Thin magnetic film including multiple geometry gap structures on a common substrate
US5665251A (en) 1994-11-23 1997-09-09 International Business Machines Corporation RIE image transfer process for plating
US5606478A (en) 1994-12-08 1997-02-25 International Business Machines Corporation Ni45 Fe55 metal-in-gap thin film magnetic head
US5602703A (en) * 1994-12-27 1997-02-11 Seagate Technology, Inc. Recording head for recording track-centering servo signals on a multi-track recording medium
JPH08234410A (en) 1995-02-28 1996-09-13 Dainippon Printing Co Ltd Phase shift photomask and dry etching method for phase shift photomask
US5531570A (en) * 1995-03-06 1996-07-02 General Electric Company Distortion control for laser shock peened gas turbine engine compressor blade edges
US5593065A (en) 1995-04-10 1997-01-14 Pakmax, Inc. Metered dual dispenser cap for squeeze containers
JP2001517348A (en) 1995-06-05 2001-10-02 松下寿電子工業株式会社 Associated with the shield that is shared on the magnetoresistive read head, the flux enhanced write transducers and process for manufacturing it
US5615069A (en) 1995-06-07 1997-03-25 Seagate Technology, Inc. Thin-film transducer design for undershoot reduction
JP3464320B2 (en) 1995-08-02 2003-11-10 株式会社荏原製作所 Processing method and processing apparatus using a fast atom beam
JP4115526B2 (en) 1995-11-13 2008-07-09 クウォンタム・コーポレイション Head tilting mechanism for azimuth recording in tape drives
FR2741470B1 (en) 1995-11-22 1998-01-02 Commissariat Energie Atomique A method of making a planar magnetic head and head obtained by this method
US5742452A (en) 1996-01-10 1998-04-21 International Business Machines Corporation Low mass magnetic recording head and suspension
US5867339A (en) 1996-01-11 1999-02-02 Quantum Corporation Two channel azimuth and two channel non-azimuth read-after-write longitudinal magnetic head
US5920447A (en) * 1996-03-14 1999-07-06 Kabushiki Kaisha Toshiba Magnetic disk unit having laminated magnetic heads
US5940238A (en) 1996-06-07 1999-08-17 Seagate Technology, Inc. Mechanism to reduce adjacent track interference in a magnetic tape data storage system
US5710673A (en) 1996-06-07 1998-01-20 Ampex Corporation Azimuth record head for minimizing and equalizing crosstalk between tracks of opposite azimuths
US5726841A (en) 1996-06-11 1998-03-10 Read-Rite Corporation Thin film magnetic head with trimmed pole tips etched by focused ion beam for undershoot reduction
US5752309A (en) 1996-06-14 1998-05-19 Quantum Corporation Method and apparatus for precisely dimensioning pole tips of a magnetic transducing head structure
US5719730A (en) 1996-07-17 1998-02-17 Headway Technologies, Inc. Low fringe-field and narrow write-track magneto-resistive (MR) magnetic read-write head
US5680278A (en) 1996-08-08 1997-10-21 Quantum Corporation Apparatus for combining linear and rotational motion of an azimuth read/write head
US5757575A (en) 1996-10-31 1998-05-26 Ampex Corporation Track-curvature detection using clock phase shift in azimuth recording
US5793577A (en) 1996-11-01 1998-08-11 Read-Rite Corporation Planar geometry thin film head with shaped poles
US6165649A (en) 1997-01-21 2000-12-26 International Business Machines Corporation Methods for repair of photomasks
US5966632A (en) 1997-01-21 1999-10-12 Mosel Vitelic Inc. Method of forming borderless metal to contact structure
US5890278A (en) 1997-04-01 1999-04-06 U.S. Philips Corporation Method of manufacturing a magnetic head having a structure of layers
US5831792A (en) 1997-04-11 1998-11-03 Western Digital Corporation Slider having a debris barrier surrounding a transducer
US5995315A (en) 1997-05-09 1999-11-30 Hewlett-Packard Company Servo system for following a magnetic track having identifying pulse widths
US5768070A (en) 1997-05-14 1998-06-16 International Business Machines Corporation Horizontal thin film write, MR read head
US5930065A (en) 1997-05-16 1999-07-27 International Business Machines Corporation Timing based servo longitudinal addressing
US6005737A (en) 1997-05-24 1999-12-21 Seagate Technology, Inc. Magnetic tape drive having improved servo control
US5982711A (en) 1997-06-05 1999-11-09 Hewlett-Packard Co. Device for reading data from or writing data to magnetic storage media and a method of positioning a tape head relative to the magnetic storage media
US5923272A (en) 1997-07-08 1999-07-13 International Business Machines Corporation Serial bitstream code for timing-based servo
US6025970A (en) 1997-08-07 2000-02-15 International Business Machines Corporation Digital demodulation of a complementary two-frequency servo PES pattern
US6034835A (en) 1997-08-07 2000-03-07 International Business Machines Corporation Multiple servo track types using multiple frequency servo patterns
US5966264A (en) 1997-08-07 1999-10-12 International Business Machines Cororation Two frequency servo PES pattern
US6163421A (en) 1997-09-05 2000-12-19 Sony Corporation Azimuth magnetic recording and reproducing apparatus and method employing waveform equalization
US6018444A (en) 1997-10-28 2000-01-25 Hewlett-Packard Company Batch fabricated servo write head having low write-gap linewidth variation
US6163436A (en) 1997-11-19 2000-12-19 Tdk Corporation Thin film magnet head with improved performance
US6081401A (en) 1997-12-23 2000-06-27 Ampex Corporation Step gap head tracking servo
US6169640B1 (en) * 1998-03-04 2001-01-02 Hewlett-Packard Co. Servo band identification in linear tape systems having timing based servo formats
US6031673A (en) * 1998-03-04 2000-02-29 Hewlett-Packard Company Servo band verification in linear tape systems having timing-based servo formats
US6111719A (en) 1998-03-06 2000-08-29 Hewlett-Packard Company Linear speed measurement independent of lateral position in linear tape systems
US6075678A (en) 1998-03-24 2000-06-13 Quantum Corporation Pivoting lever cam guide tape head positioner
US6275350B1 (en) 1998-04-03 2001-08-14 Hewlett-Packard Company Magnetic head and method for compensating for magnetic tape dimensional instability
US6118630A (en) 1998-04-23 2000-09-12 International Business Machines Corporation Compliant edge guiding and following system for tape
US6222698B1 (en) 1998-05-22 2001-04-24 Hewlett-Packard Company Magnetic tape dimensional instability compensation by varying recording head azimuth angle
US6088184A (en) 1998-06-16 2000-07-11 International Business Machines Corporation Apparatus and method for the control and positioning of magnetic recording heads in an azimuth recording system
US6141174A (en) 1998-08-14 2000-10-31 Quantum Corporation Method of reading recorded information from a magnetic tape that compensates for track pitch changes
US6236525B1 (en) 1998-08-14 2001-05-22 Storage Technology Corporation Tape head with pattern timing for servo writing application
US6369982B2 (en) 1998-09-08 2002-04-09 Quantum Corporation Floating tape head having side wings for longitudinal and azimuth play back with minimized tape wrap angle
US6156487A (en) 1998-10-23 2000-12-05 Matsushita-Kotobuki Electronics Industries, Ltd. Top surface imaging technique for top pole tip width control in magnetoresistive read/write head processing
JP3180906B2 (en) 1998-11-12 2001-07-03 日本電気株式会社 Method for manufacturing a magneto-resistance effect type composite head
US7196870B2 (en) 1999-02-23 2007-03-27 Advanced Research Corporation Patterned magnetic recording head with termination pattern having a curved portion
US6269533B2 (en) 1999-02-23 2001-08-07 Advanced Research Corporation Method of making a patterned magnetic recording head
US20030093894A1 (en) * 1999-02-23 2003-05-22 Dugas Matthew P. Double layer patterning and technique for making a magnetic recording head
US6542325B1 (en) 1999-03-10 2003-04-01 Imation Corp. Time-based servo for magnetic storage media
US6362934B1 (en) * 1999-03-24 2002-03-26 Storage Technology Corporation Highly aligned thin film tape head and method of making same
US7130152B1 (en) 1999-04-01 2006-10-31 Storage Technology Corporation High track density magnetic recording head
WO2001004725A3 (en) 1999-07-09 2001-06-28 Design And Test Technology Inc Servo write head
JP3551099B2 (en) * 1999-09-28 2004-08-04 日本電気株式会社 Magnetic tape apparatus for a thin film magnetic head
JP2001110027A (en) 1999-10-08 2001-04-20 Hitachi Ltd Magnetic storage
US6754026B1 (en) 1999-10-28 2004-06-22 International Business Machines Corporation Tape transport servo system and method for a computer tape drive
KR100348902B1 (en) 1999-11-30 2002-08-14 한국전자통신연구원 Method of manufacturing a gamma gate of hemt
US6545837B1 (en) 1999-12-21 2003-04-08 Imation Corp. Method and apparatus for servo controlled azimuth data recording
US6989960B2 (en) * 1999-12-30 2006-01-24 Advanced Research Corporation Wear pads for timing-based surface film servo heads
US6496328B1 (en) 1999-12-30 2002-12-17 Advanced Research Corporation Low inductance, ferrite sub-gap substrate structure for surface film magnetic recording heads
US6574066B1 (en) 2000-02-17 2003-06-03 Imation Corp. Time-based optical servo system and method
US6444408B1 (en) 2000-02-28 2002-09-03 International Business Machines Corporation High silicon content monomers and polymers suitable for 193 nm bilayer resists
US6721126B1 (en) 2000-08-16 2004-04-13 International Business Machines Corporation Position identification for a coarse actuator portion of a compound actuator
JP3838329B2 (en) 2000-09-27 2006-10-25 信越化学工業株式会社 Polymeric compound, a resist composition, and patterning process
US6700729B1 (en) 2000-10-17 2004-03-02 Hewlett-Packard Development Company Alignment marks for tape head positioning
CN1457490A (en) 2001-03-06 2003-11-19 皇家菲利浦电子有限公司 Magnetic-tape apparatus with pressure-roller device and pressure-roller unit
US6670093B2 (en) 2001-04-06 2003-12-30 Industrial Technology Research Institute Silicon-containing copolymer and photosensitive resin composition containing the same
JP2002312907A (en) 2001-04-13 2002-10-25 Sony Corp Magnetic mead and its manufacturing method
US6650496B2 (en) 2001-05-15 2003-11-18 Phs Mems Fully integrated matrix magnetic recording head with independent control
US6865050B2 (en) * 2001-06-07 2005-03-08 Fuji Photo Film Co., Ltd. Servo signal recording device and servo signal verifying device using edge detection
US6781778B1 (en) 2001-07-16 2004-08-24 Imation Corp. Time-based sectored servo data format
JP2003029038A (en) 2001-07-17 2003-01-29 Nitto Denko Corp Optical film, a polarizing plate and a display device
US6963467B2 (en) 2001-07-17 2005-11-08 International Business Machines Corporation Method and apparatus for compensating for media shift due to tape guide
US6985323B2 (en) 2001-09-12 2006-01-10 Exabyte Corporation Alternating-azimuth angle helical track format using grouped same-azimuth angle heads
US6873487B2 (en) * 2001-11-26 2005-03-29 Imation Corp. Hybrid servopositioning systems
JP3830088B2 (en) 2001-11-29 2006-10-04 富士写真フイルム株式会社 Servo control method, a magnetic tape, and a magnetic tape recording and reproducing apparatus
US6744594B2 (en) * 2001-12-28 2004-06-01 Storage Technology Corporation Servo write head with gaps for writing high and low frequency transitions
US6622490B2 (en) 2002-01-11 2003-09-23 Watson Cogeneration Company Turbine power plant having an axially loaded floating brush seal
US6798608B2 (en) 2002-01-18 2004-09-28 International Business Machines Corporation Active detection and acquisition of a servo track subject to lateral motion
US6801383B2 (en) 2002-04-04 2004-10-05 Quantum Corporation Method for calibrating a tape media using staggered calibration tracks
US6831805B2 (en) 2002-06-27 2004-12-14 International Business Machines Corporation Apparatus and method to read and/or write information to a magnetic tape medium
US6950277B1 (en) 2002-10-25 2005-09-27 Maxtor Corporation Concave trailing edge write pole for perpendicular recording
US6970312B2 (en) 2002-12-23 2005-11-29 Imation Corp. Full amplitude time-based servopositioning signals
US6943987B1 (en) 2002-12-27 2005-09-13 Storage Technology Corporation Servo write head
US6947256B2 (en) 2003-01-29 2005-09-20 International Business Machines Corporation Embedded wire planar write head system and method
US6947247B2 (en) 2003-03-05 2005-09-20 Advanced Research Corporation Large angle azimuth recording and head configurations
JP2004318977A (en) 2003-04-15 2004-11-11 Fuji Photo Film Co Ltd Magnetic tape and its manufacturing method, and servo writer
US7106544B2 (en) 2003-05-09 2006-09-12 Advanced Research Corporation Servo systems, servo heads, servo patterns for data storage especially for reading, writing, and recording in magnetic recording tape
US7244997B2 (en) 2003-07-08 2007-07-17 President And Fellows Of Harvard College Magneto-luminescent transducer
JP2005063623A (en) * 2003-08-20 2005-03-10 Fuji Photo Film Co Ltd Servo writer and servo writing method
JP4095513B2 (en) 2003-09-05 2008-06-04 富士フイルム株式会社 Servo writer and a servo writing method
JP2005085390A (en) 2003-09-09 2005-03-31 Fuji Photo Film Co Ltd Complex type magnetic head and manufacturing method therefor
JP4046284B2 (en) 2003-09-11 2008-02-13 富士フイルム株式会社 Magnetic tape and a method for producing the same, and a method of writing servo writer and servo signals
US7142381B2 (en) 2003-11-10 2006-11-28 Imation Corp. Servo writing devices for creating servo patterns with inherent track ID
US7038871B2 (en) 2003-11-10 2006-05-02 Imation Corp. Multi-band servo patterns with inherent track ID
JP2005166193A (en) 2003-12-04 2005-06-23 Fuji Photo Film Co Ltd Composite magnetic head and manufacturing method thereof
US20050152066A1 (en) 2004-01-08 2005-07-14 Imation Corp. System with matrix array of write heads and array of magnetoresistive (MR) read heads
US7283317B2 (en) 2004-01-30 2007-10-16 Advanced Research Corporation Apparatuses and methods for pre-erasing during manufacture of magnetic tape
US7301716B2 (en) 2004-02-17 2007-11-27 Advanced Research Corporation Stepped time based servo pattern and head
US7199957B2 (en) 2004-03-30 2007-04-03 Imation Corp. Write head alignment for full amplitude time-based servo
US7450341B2 (en) 2004-05-04 2008-11-11 Advanced Research Corporation Intergrated thin film subgap subpole structure for arbitrary gap pattern magnetic recording heads and method of making the same
US7206170B2 (en) * 2004-05-19 2007-04-17 Imetion Corp. Thin film servo head apparatus with canted servo gaps
US7119976B2 (en) 2005-01-12 2006-10-10 International Business Machines Corporation Planar servo format verifier head
JP4103009B2 (en) 2005-03-23 2008-06-18 セイコーエプソン株式会社 Droplet ejection apparatus, and a microarray production method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5321570A (en) * 1989-10-02 1994-06-14 Behr Michael I Systems using superimposed, orthogonal buried servo signals
US5523904A (en) * 1992-06-24 1996-06-04 Quantum Corporation Linear tape write servo using embedded azimuth servo blocks
US5572392A (en) * 1994-11-17 1996-11-05 International Business Machines Corporation Arbitrary pattern write head assembly for writing timing-based servo patterns on magnetic storage media
US7072133B1 (en) * 2001-10-15 2006-07-04 Imation Corp. Servo mark verify head
US20030151844A1 (en) * 2002-02-13 2003-08-14 International Business Machines Corporation Timing based servo with fixed distances between transitions
US20060126207A1 (en) * 2004-06-02 2006-06-15 Imation Corp. Dual mode servo pattern

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8817415B2 (en) 2011-06-13 2014-08-26 Imation Corp. Erasure of magnetic storage media having perpendicular anisotropy
US8767342B2 (en) 2011-06-13 2014-07-01 Imation Corp. Erasure and servowriting of magnetic storage media having perpendicular anistropy
US8797674B2 (en) 2011-06-13 2014-08-05 Imation Corp. Servo mark length matched to write head gap for magnetic storage media
US8804276B2 (en) 2011-06-13 2014-08-12 Imation Corp. Continuous biasing and servowriting of magnetic storage media having perpendicular anisotropy
US8867157B2 (en) 2012-04-04 2014-10-21 Imation Corp. Perpendicular pole head for servo writing magnetic media
US8797681B2 (en) * 2012-04-26 2014-08-05 Imation Corp. Servo write head having plural spaced front blocks coupled by magnetic posts to a back bar
US20130286506A1 (en) * 2012-04-26 2013-10-31 Imation Corp. Servo write head
US8760802B2 (en) 2012-04-26 2014-06-24 Imation Corp. Systems and methods for processing magnetic media with first and second magnetic gaps adjacent opposite sides of the recording layer
US8867167B2 (en) 2012-04-26 2014-10-21 Imation Corp. Tapered pole heads for magnetic media
US8947802B2 (en) 2012-04-26 2015-02-03 Imation Corp. Methods and systems for magnetic media servo writing

Also Published As

Publication number Publication date Type
US20050157422A1 (en) 2005-07-21 application
US8144424B2 (en) 2012-03-27 grant

Similar Documents

Publication Publication Date Title
US3514851A (en) Method of manufacturing a magnetic head structure
US6829819B1 (en) Method of forming a magnetoresistive device
US6093083A (en) Row carrier for precision lapping of disk drive heads and for handling of heads during the slider fab operation
US4149204A (en) Minor bit reduction on a magnetic head
US20060126207A1 (en) Dual mode servo pattern
US4825318A (en) Compound read/write element for rigid magnetic disk files
US6700729B1 (en) Alignment marks for tape head positioning
US5438747A (en) Method of making a thin film merged MR head with aligned pole tips
US5142768A (en) Method for making magnetic head with enhanced poletip
US5394285A (en) Multi-track longitudinal, metal-in-gap head
US5198948A (en) Shielded servo heads with improved passive noise cancellation
US5452166A (en) Thin film magnetic recording head for minimizing undershoots and a method for manufacturing the same
US5883760A (en) Magnetic structure and magnetic head using the same
US6236525B1 (en) Tape head with pattern timing for servo writing application
US20050152067A1 (en) System with matrix array of write heads and matrix array of magnetoresistive (MR) read heads
US6038108A (en) Magnetic tape head assembly having segmented heads
US3881190A (en) Shielded magnetoresistive magnetic transducer and method of manufacture thereof
US5896249A (en) Disk drive with identical top and bottom heads having three side-by-side elements and a common terminal pad
US8786983B1 (en) Magnetic writer having a low aspect ratio two layer coil
US4489484A (en) Method of making thin film magnetic recording heads
EP0301823A2 (en) Three-pole magnetic recording head
US20040156148A1 (en) Magnetic recording head with a side shield structure for controlling side reading of thin film read sensor
US4012781A (en) Magnetoresistive read head assembly for servo operation
US7100266B2 (en) Method of forming a beveled writing pole of a perpendicular writing element
US5331493A (en) Bidirectional thin-film magnetoresistive tape head assembly