Abstract: A servo write head assembly comprises an AC demagnetizing head that slides in contact with a magnetic tape all of which surface is magnetized in one direction of longitudinal directions thereof, and demagnetizes a data band of the magnetic tape; a servo write head that slides in contact with the magnetic tape, magnetizes a servo band of the magnetic tape in a reverse direction, and writes a servo signal; and a guide for regulating a movement in lateral directions of the magnetic tape that is running, wherein the AC demagnetizing head and the servo write head are integrally configured and the guide is provided between the AC demagnetizing head and the servo write head.

Abstract: A servo write head assembly comprises an AC demagnetizing head that slides in contact with a magnetic tape all of which surface is magnetized in one direction of longitudinal directions thereof, and demagnetizes a data band of the magnetic tape; a servo write head that slides in contact with the magnetic tape, magnetizes a servo band of the magnetic tape in a reverse direction, and writes a servo signal; and a guide for regulating a movement in lateral directions of the magnetic tape that is running, wherein the AC demagnetizing head and the servo write head are integrally configured and the guide is provided between the AC demagnetizing head and the servo write head.

Abstract: Disclosed is a low-cost servo writer with a simple adjusting mechanism, which can record/reproduce servo signals on or from magnetic tapes precisely, and which makes it possible to shorten the adjusting and maintenance time and to minimize the uneven wear of its heads, thereby decreasing the level of contaminant of the heads. The servo writer includes (a) a head for recording/reproducing servo signals on or from a running tape, (b) a base, (c) a support arm having two ends, one of the ends being supported by the base, the other being a free end where the head is placed, wherein a position of the head relative to the tape is adjustable, and (d) tape guides for maintaining a constant lap angle, the tape guides being arranged on the free end of the support arm, wherein the lap angle is an angle which the head forms with the running tape.

Abstract: According to one aspect, methods and systems for determining the position of a recording head using existing data structures on magnetic storage media are provided. In one example, a recording head writes data to an active track on a magnetic storage tape, the recording head including a write element and a read element in a known spatial relationship, wherein the read element is configured to access at least a portion of a reference track when the write element is accessing the active track. A controller determines a relative position of the transducer element to the reference track and repositions the recording head to write data to the active track. The read element may be a backward channel reader or dedicated read element of the recording head for reading reference tracks during read and/or write operations.

Abstract: A magnetic storage medium formed on a front major surface of a tape substrate defines a multiplicity of longitudinal data recording and playback tracks, each track having a nominal lateral location relative to the other tracks: and a predetermined optically manifested track servo pattern defined on the back major surface of the tape for indicating lateral displacement of the tape from a nominal lateral location of the track during tape movement across a read/write head. A magnetic tape recording and playback system employing the magnetic storage medium is also disclosed.

Abstract: Disclosed are a system, a method, and article of manufacture to provide a compensator for a synchronous sampling servo control system.

Abstract: Disclosed is a magnetic tape which contributes to a high recording density, and which achieves an enhanced flexibility in a width of a data track and a data format. The magnetic tape includes servo tracks being recorded thereon. These servo tracks contain respective servo signals, and are arranged lengthwise and adjacent to one another over a whole of a width or a part of the magnetic tape. Further, each of the servo tracks includes address signals being recorded thereon at predetermined intervals in isolation from the corresponding servo signals. These address signals indicate their respective locations of corresponding one of the servo tracks and their respective lengthwise locations on the magnetic tape. In addition, the servo signals are read from the respective servo bands, and are used to adjust tracking of a magnetic head on the magnetic tape.

Abstract: A data storage apparatus comprises a tape cartridge having a cartridge memory which is configured to store data representing a distinctive identity of the memory and data representing a distinctive identity of the cartridge. The cartridge has a data storage tape storing WORM data in a succession of data sets. Each data set is recorded with data representing a respectively associated data set information table. The data set information table includes an identifying data structure including data representing the identity of the cartridge memory and the data representing the identity of the cartridge. The integrity of all the WORM data written at any point along the tape can be checked against tampering by reference to the data structure that is recorded with each WORM data set.

Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.

Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.

Abstract: The present invention provides servo systems and accompanying methods for determining the relative position of a transducer head to a magnetic storage tape utilizing existing data structures on the magnetic storage tape and the position of the tape edge. In one example, a method for positioning a transducer head relative to a magnetic storage medium includes sensing a read signal from a read element associated with a transducer head, the read signal in response to a reference data track stored on a magnetic storage medium, optically sensing a position of an edge of the storage medium, and repositioning the transducer head relative to the storage medium in response to the read signal and the position of the edge of the storage medium.

Abstract: A magnetic tape drive has a servo head for performing the tracking control and a head unit. The head unit includes a recording head group composed of a plurality of recording heads, which are lined up along the width directions with respect to a magnetic tape. In this head unit, the distance between the recording heads is the same distance as the distance between adjacent data tracks to be formed on the magnetic tape, and the azimuth angle of each recording heads differs with each other. A plurality of data tracks are simultaneously formed on the magnetic tape using a plurality of recording heads, respectively, when performing the recording of data on the magnetic tape.

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

Abstract: A magnetic tape drive of the present invention is the drive that has a head unit comprising a servo head for trackings and a recording head group, which comprises a plurality of data signal recording heads, wherein the plurality of the data signal recording heads are formed at a pitch corresponding to that of adjacent data tracks on a magnetic tape, and wherein a plurality of adjacent data tracks are simultaneously formed on the magnetic tape with the plurality of the data signal recording heads.

Abstract: A magnetic tape which is run at a speed of 4 m/sec. or higher and has recording tracks with a width of 21 ?m or less, and which includes a non-magnetic support, at least one magnetic layer formed on one surface of the non-magnetic support, and a backcoat layer formed on the other surface of the non-magnetic support, wherein servo signals for controlling tracking are recorded on the magnetic layer or the backcoat layer, the value of (?/W) X (V/f) is 10 [s?1] or less, and/or the value of (?/W) is 0.1 or less, wherein V [mm/sec.] is the tape-running speed; ? [?m] is an amount of a weave with a cycle of f [mm] on one edge of the tape or the other edge thereof, as the reference side, for the running of the tape; and W [?m] is a width of the recording track. The magnetic tape can decrease PES and off-track and thus is excellent in servo tracking performance.

Abstract: In one aspect, an electromagnetic or capacitive sensing position system for determining the relative position of at least one void in a conductive material is provided. In one example, the system includes a sensor (or probe) having at least two probe elements (e.g., tips or plates). The position of the probe relative to the at least one void is determined in response to an electrical signal (e.g., a differential signal) measured across the two probe elements that varies in response to interaction of the probe elements with the at least one void. The system may be used, e.g., to servo a magnetic head assembly relative to a magnetic storage tape.

Abstract: A method and apparatus for reducing tape media edge damage in data regions. The present invention controls where popped strand occur by shifting the wrap turn around/stream points in the tape media to an unused region of tape. As data is written for the length of the tape, when a wrap turn around point is reached, the write current is shut off. However, the servo motors in the tape drive continue to stream the tape for a predefined distance past the turn around point. The head may then be moved transversely to acquire a new track. The tape may then be spooled in the reverse direction on the new track. When a wrap point is encountered, the write current may be turned on and the next track (wrap) may be written. This combination of steps may be repeated for each serpentine wrap on the tape.

Abstract: A compact optical tracking system for magnetic tape is disclosed which is independent of the magnetic format and head structure which can generate a position error signal without encoding on the servo track. A plurality of optical servo modules is arranged in a linear array. Each optical servo module contains an optical beam source, preferably a laser, an optical beam interference composite hologram for producing a predetermined pattern on a target and at least one detector for detecting an optical beam reflection. A position correction signal is generated by one or all of the optical servo modules for re-positioning a magnetic head, which reduces the error in the correction signal from tape degradation and dimensional changes. Reference grating may be added to provide further position calibration prior to the tape being positioned over the head.

Abstract: The invention combines the benefits of sectored servo data with the benefits of time-based servo data. Recording media such as magnetic tape, magnetic disks, optical tape and optical disks can store servo data in a time-based sectored servo format.

Abstract: A storage device in which file data is divided into multiple blocks for storage on a recording medium. The storage device includes an additional data storing section for storing additional data to be recorded on the recording medium in association with the data to be written, a position determining section for determining recording positions on the recording medium where the blocks should be respectively written, based on the additional data, and a block writing section for writing the respective blocks on the recording positions on the recording medium determined by the recording position determining section. The additional data thus defines a gap length between blocks of recorded data. During a read operation, if the gap length does not comport with the additional data, then an error is assumed.

Abstract: A recording target error rate is selected for one or more of data storage devices, and for each data storage device, a dither value is determined for each read/write head in the data storage device, wherein for each head, using a dither value for writing data, essentially provides the selected recording target error for all the heads.

Abstract: An actuator device includes a pole piece and at least one magnet for generating a magnetic field. A coarse positioner having a coil surrounding the pole piece provides coarse actuation in a direction parallel to an axis of the pole piece. A fine positioner having a coil surrounding the pole piece provides fine actuation in a direction generally parallel to an axis of the pole piece.

Abstract: Detecting of a lower limit of tape head travel in a single reel tape drive discontinues signaling a tape head to move downward during initialization when the tape head as reach the lower limit of travel. Upon initialization, a processor steps the tape head housing to the lower limit of travel. A mechanical link at the bottom of the tape head engages a tape guide within a tape path and moves the tape guide away from the tape head. Movement of the tape guide pulls additional takeup leader from the takeup reel which rotates the guide rollers within the tape path. A tachometer coupled to one of the guide rollers within the tape path adjust a tachometer count which is monitored by the processor. In response to the change in the tachometer count, the processor discontinues stepping the tape head housing downward.

Abstract: First, data is read from tracks formed on a tape-shaped recording medium by heads disposed on a rotary drum, to measure error rates. Next, of the tracks formed on the tape-shaped recording medium, a worst track suffering the highest error rate is detected based on the error rates thus measured. Then, a pair of reproducing heads that can reproduce the worst track thus detected at the lowest error rates is detected from the measured error rates. Thereafter, tracking servo control is performed such that the worst track can be scanned by the pair of reproducing heads. As a result, a reproducing apparatus capable of proper reproduction even when recorded tracks undergo variations in width and reproducing heads are erroneously mounted.

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

Abstract: The invention provides a linear data storage medium, such as magnetic tape, in which data tracks that extend in one direction are recorded at a different density than data tracks recorded in the opposite direction. Various techniques are also described to facilitate such dual density recording. The invention is particularly advantageous for direction-dependent linear data storage media, by allowing similar error rates to be achieved in both directions on the media.

Abstract: In an apparatus for reproducing a recorded signal and the like of this invention, two reproducing heads are provided for a single track with their set positions being deviated in the track width direction. A signal selecting unit discriminates a reproducing head whose tracing condition of a target track is appropriate based on an error correction result of a C1 correcting unit and output levels of reproducing heads. A signal obtained by the discriminated reproducing head is supplied to a C2 correcting unit to generate an output signal. Consequently, an off track allowance is increased as compared with a case where the target track is traced with a single reproducing head. At the time of a special reproducing operation or even if a narrow track pitch system is adopted, a recorded signal is reproducible properly.

Abstract: The invention is directed to servo techniques that make use of sequences of servo marks, rather than individual marks for generation of position error signals. In particular, random or pseudo-random sequences of servo marks may be recorded on the medium in an overlapping fashion. For example, a first sequence of marks and a second sequence of marks may overlap in the servo track. The second sequence may be substantially non-correlated with the first sequence, and may be recorded in an offset location along the track relative to the first sequence. Different correlators can be used to detect the different sequences, and position error signals can be generated based on timings associated with the detection of the first sequence relative to the second sequence.

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

Abstract: Modern tape drives can adjust their tape drive velocity between two or more read/write data rates to better match the data rate demands of the host. This velocity changing may provide improvements in drive performance and total backhitch counts. The transition from one tape velocity to another may involve a rate change backhitch which itself could impact performance. It is desirable to optimize these transitions. In one approach, a backhitch involves a backvelocity having a magnitude that is intermediate between the initial tape velocity and the final tape velocity. In another approach, a backhitch involves an intermediate forward velocity to quicken the approach toward the start R/W reposition point.

Abstract: A technique of positioning a recording head relative to an optical servo system in a magnetic recording tape system read/write assembly is described. The technique includes positioning an optical sensor of the optical servo system at a first position relative to a selected one of recording channels on the recording head and positioning the optical sensor at a second position relative to the selected recording channel using an alignment target on the recording head. A recording head in a read/write assembly of a magnetic recording tape system is also described. The recording head includes recording channels fabricated on a wafer and an alignment target affixed to the wafer between a first read-write element of a recording channel and a second read-write element of the recording channel, the alignment target fabricated to produce an optical reflectance signal.

Abstract: Tape drive systems and methods for operating tape drive systems are provided. The system includes a head assembly having a head element for reading or writing data to a magnetic tape medium, and a pressure sensor coupled to the head element, the pressure sensor configured to generate a pressure signal representative of a pressure applied by the head element onto the pressure sensor. In some embodiments, an accelerometer is provided for sensing an acceleration of the head assembly and for generating a acceleration signal representative of an acceleration experienced by the head assembly. The method includes passing a tape medium between a take-up reel and a supply reel such that a tension in the tape medium causes the tape medium to apply a pressure onto a head element, and using a pressure sensor to detect a pressure applied by the head element onto the pressure sensor.

Abstract: The present invention uses Electronic Lapping Guides (ELG's), which are patterned on every tape head, as servo format verifiers. This is implemented by specifically placing the ELG's at the appropriate locations to match the servo signal track locations and thus be usable to verify the servo format patterns on the formatted tape. According to another aspect of the present invention, tape head components which have faulty read sensors, servo sensors, or write elements which have valid ELG's may be used for the servo format verification purpose.

Abstract: The present invention is relative to a recording and/or reproducing apparatus having a cassette tape exchanging function of selectively taking out a cassette tape (1) accommodated in a cassette holder (130) for recording or reproducing information signals. A cassette tape driving device (150) is arranged in an inner area of a toroidally-shaped rotational plate (121) passing through the proximity of a cassette insertion/ejection opening (112) formed in a front panel (111) of a cabinet (110). The cassette tape accommodated in the cassette holder is pushed towards the cassette tape driving device by grip arms (162A), (162B) of a cassette holding mechanism (160) mounted on the opposite side of the cassette insertion/ejection opening (112) or is pulled out so as to be accommodated in the cassette tape holder.

Abstract: In a magnetic recording and reproducing device having a 1ch head and a 2ch head, an azimuth recording operation is carried out on an obliquely evaporated magnetic tape. Angles ?1 and ?2 formed by a direction of a head azimuth of the 1ch head and the 2ch head and a longitudinal direction of the magnetic tape are respectively set to angles at which an output difference between a reproducing signal of a track recorded by the 1ch head and a reproducing signal of a track recorded by the 2ch head is located within three decibels. Thus, an output difference between the two magnetic heads is reduced while the loss of electromagnetic conversion is reduced.

Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.

Abstract: A method for sensing position that comprises generating light, eclipsing the light according to position, sensing the amount of light not eclipsed, and inferring position according to the sensed amount of light.

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

Abstract: A method and system of a head for use with a storage media having a first set of read transducers positioned to compensate for shrinkage of the storage media, and a second set of read transducers positioned to compensate for expansion of the storage media.

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

Abstract: In one embodiment, a servo positioning method includes deriving a first servo signal S1 from a first servo band, deriving a second servo signal S2 from a second servo band, defining a head element reference between the servo bands, weighting each servo signal according to a ratio of distances between the head element reference and a location on each servo band, and computing a servo control signal based on the weighted servo signals.

Abstract: An apparatus for helical scan recording/playback of preselected tacks on a flexible tape medium comprising a linear slide structure capable of movement transversely relative to a longitudinal direction of the tape medium, the linear slide structure including a scanner/drum capable of sliding movement relative to a longitudinal direction of the tape medium between opposed edges of the tape medium defining a recording area, the scanner/drum having a head stack for helical scan recording/playback of the preselected tracks, and a stepper motor on a trolley end of the linear slide structure for causing the scanner/drum to slide transversely relative to the longitudinal direction of the tape medium.

Abstract: A magnetic tape of the present invention comprises a plurality of servo bands and servo signals for performing tracking-control of a magnetic head, wherein the servo signals are recorded on the servo bands, wherein a DC magnetization region magnetized in one direction by direct current is arranged along longitudinal directions of the magnetic tape on the servo bands, wherein each of the servo signals is magnetized in a reverse direction for the one direction of a DC magnetization and is recorded within the DC magnetization region, and wherein any of a relative ratio and relative difference of DC magnetization intensity in the DC magnetization region and recording magnetization intensity of each of the servo signals differs for each of the servo bands.

Abstract: A storage medium is provided that includes a magnetic recording tape having a first side and a second side, and a plurality of optically detectable indicia embedded in a servo layer disposed between the first side and the second side of the tape. The optical reflectivity and/or phase of the indicia are different from the surrounding servo layer, and the indicia are optically accessible from at least one of the first side and the second side of the tape. The servo layer may include an organic material wherein the indicia are created with an infrared or ultra violet light source.

Abstract: A method and apparatus for compensating for media shift due to spiral groove roller tape guide is disclosed. The lateral tape shift is measured. Then the control of the coarse actuator is adjusted for the lateral tape shift so that the movement of the coarse actuator follows the tape shift.

Abstract: A method and a system for formatting a magnetic tape with identifiable optical servo tracks are disclosed. Multiple optically detectable servo tracks extending lengthwise parallel to the tape transport direction are written simultaneously by directing a spatial beam dot pattern unto the magnetic tape. The beam dot pattern is capable of imparting not only a unique identification, but also other information such as tape longitudinal address, and manufacturer's data to each servo track. The spatial beam dot pattern may also include two arrays of beam dots created via the use of two one-dimensional diffractive optical elements.

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

Abstract: Servopositioning data is written onto a linear recording medium such that a position error signal is intentionally created. Precise control over the distance between servo signals simulates position error signals at any frequency or magnitude. Drives that normally assume that such distance is constant perceive the simulated position error signals as vertical tape motion. Thus, a servo writer can create such signals at pre-determined levels within the servo pattern.

Abstract: Large angle azimuth recording methods and devices. In one aspect of the invention methods of recording one or data tracks having data transitions oriented at a large azimuth angle are provided. In another aspect of the invention methods of reading a data track having data transitions oriented at a large azimuth angle are provided. Such methods include steps of suppressing a side track signal. In other aspects of the invention, head modules and devices for writing and/or reading large azimuth angle data tracks are provided.

Abstract: An arrangement and method for compensating for the written-in tracking error for a linear tape drive filters out spatial error components of a position error signal (PES). The position information contained within A, B pairs of servo stripes, and within C, D pairs of stripes is preserved. The timing between the A and C bursts and the C and A bursts is filtered, such as by low pass filtering, to filter out the error that can be written-in by a servo writer. The timing signal for the A, B bursts and C, D bursts are divided by the filtered timing signals for the AC and CA timing signals, respectively. This ratio provides the filtered PES signal used by a head positioner to precisely position the head with respect to the tape.