Abstract: A method and apparatus to read calibration information from a calibration region encoded in a tape information storage medium while acquiring a plurality of valid calibration signals. The method provides (N) read/detect channels. The method establishes a valid calibration signal threshold, and detects at a first time the (i)th valid calibration signal. The method further determines at the first time the frequency and phase of that (i)th valid calibration signal using a first PLL component disposed in the (i)th read/detect channel. The method determines if the valid calibration signal threshold is exceeded. If the valid calibration signal threshold is exceeded, the method then provides the frequency and phase to a second PLL component, and reads information encoded on the tape medium using that second PLL component.

Abstract: The present invention provides a method of describing defects that requires less memory space than conventional methods. Entries of a first defect table are sorted according to the type of track layout, or zones. They are then grouped into clusters. Each cluster is characterized by a set of new parameters, including a starting sector, a scratch parameter, a span parameter, and an angle parameter. The new parameters are stored in a second table, replacing the corresponding entries in the first table. In this manner, a single entry in the second table replaces one or more entries in the first table with one entry in the first table.

Abstract: Electromagnetic radiation from an optical source is directed onto a metallic structure. The metallic structure in turn emits optical output from an emission region in the structure and onto a recording medium (e.g., a magnetic recording disk), thereby heating the medium. The output from the emission region is enhanced due to surface plasmons in the metallic structure. The surface plasmons are generated by an array of features (such as ridges or trenches) in the metallic structure and act to increase the emitted optical output from the emission region beyond what the emitted optical output from the emission region would be in the absence of these features. The apparatus and associated method are useful for data recording, e.g., thermally assisted data recording.

Abstract: The invention discloses an assembly comprising an adjustable heat flux mechanism suitable for thermally assisted information processing and control. In one embodiment, the assembly discloses a directed energy source for heating a media, a temperature sensing element for measuring/inferring the temperature of the media, and a controller for mutually positioning the energy output by the directed energy source and the media for thereby controlling the power directed to the media in accordance with the temperature sensing element.

Abstract: A system for predicting failure of a disk is provided. A test string of performance sensitive reads is built and calibrated. That is, the positioning time and spindle speed for each performance sensitive read is logged. The test string is then applied to a disk and the positioning time and spindle speed for each performance sensitive read, as applied, is measured. The calibrated positioning times and spindle speeds are then compared with the measured positioning times and spindle speeds. The comparison result is used as a reliable predictor for disk failure.

Abstract: In a disk drive of the perpendicular magnetic recording method, there is disclosed a servo data encoding method for recording servo data with a particularly low frequency on a disk. The coded data of the servo data by this method is coded with DC free code which is capable of suppressing a direct current component of the read signal waveform. As a consequence, in the case where signal processing is conducted in the read/write channel by the cut-off low frequency characteristic, a waveform distortion can be suppressed which is generated in the read signal waveform by the cut-off low frequency characteristic. Consequently, an improvement in the read error rate in the read/write channel can be realized.

Abstract: There is provided a carrier mechanism which can move a carrier section 23 to a desired position with high accuracy. The carrier mechanism is comprised of the carrier section 23, a driving motor 18, and an actuator formed of a cam mechanism 13, 15 for transmitting a driving force of the driving motor 18 to the carrier section 23 to convey the same. When the carrier section 23 is moved upward with respect to the present position, the carrier section 23 is once moved (elevated) to a position in excess of a desired position, then moved downward from the exceeded position to the desired position. When the carrier section 23 is moved downward from the present position, the carrier section 23 is moved to the desired position without exceeding the desired position. By virtue of this operation, in both of the elevation and lowering of the carrier section 23, the carrier section 23 reaches the desired section by lowering thereto at its final stage of the movement.

Abstract: A circuit and method are disclosed for relatively rapidly causing the current flowing through a write head to transition between steady states without generating an appreciable amount of capacitively-coupled noise. Embodiments of the present invention generally provide drive voltage signals to the write head that have no common mode voltage levels during transitions between steady state current levels in the write head. In other words, the drive voltage signals applied to the write head are substantially entirely differential during write head current transitions. In an exemplary embodiment of the present invention, a driver circuit includes switching circuitry connected between the terminals of the write head and reference voltage supplies, such as positive and negative voltage supplies. The driver circuit further includes timing circuitry that generates control signals for controlling the switching circuitry.

Abstract: The present invention divides the recording head into multiple sections, each section accessing a subset of the total number of channels arranged such that one section reads and writes only a subset of the data channels. The sections may be either independently actuated for both coarse (data band) and fine (track-following) positioning, or linked by a common actuator for data band positioning with independent fine position actuators for fine track following.

Abstract: A device and method for preparing media discs (2) in which servowriting and verification of the media may be carried out simultaneously. A common monolithic platform (1) is provided which supports air bearing systems which allow movement of a media disc rotary carrier (5), a servowriting headstack (3) and certifier headstack (4). Indirect drive may be provided to the rotary carrier (5) via coupling means (62).

Abstract: A slider having leading and trailing edges is configured to fly on an airbearing adjacent a data storage disk rotating from the leading edge to the trailing edge. Read and write heads are mounted on the slider proximate the trailing edge. An auxiliary thermal sensor is mounted on the slider, but preferably nearer the leading edge. Forward placement of the sensor allows it to sense mechanical defects before they reach the heads, thereby permitting a write inhibit operation, for example. The sensor may also be used to detect airbearing modulation. Appropriate action may be taken when unacceptable airbearing modulation is detected, such as notifying the user and/or scrubbing the slider. The sensor is preferably wider than the heads. This allows, for example, an in-situ glide test to be performed faster using the sensor. An arm electronics module is preferably configured to permit concurrent operation of the sensor and heads.

Abstract: In recording information, meta data defined in SMPTE 298M and 335M, buried in video and audio material signals to be recorded to a magnetic tape (30) are extracted, the thus extracted meta data or meta data generated from information other than the material signals, are written to a contactless memory tag (37), whereby it is made possible to acquire meta data about material signals recorded in a recording medium without actual reading of the material signals in the recording medium and use the meta data for search, validation, etc.

Abstract: A master carrier for magnetic transfer is equipped with a substrate with a land/groove pattern of lands and grooves, and a magnetic layer formed on the land/groove pattern. The adhesion between the substrate and the magnetic layer is 1.2×109 N/m2 or greater. A first oxygen concentration Do at the magnetic layer formed on the land is reduced gradually toward the direction of the depth of the substrate and is greater than a second oxygen concentration Dh at the magnetic layer formed on the groove.

Abstract: A magnetic signal recording method of the present invention superimposes a recording edge of a recordable region on a region where there is substantial equality between (a) a coercive force in a region on a magnetic recording medium in which the coercive force has been varied, and (b) magnetic field intensity, which is generated by a magnetic recording head. The magnetic field intensity has a magnetic field distribution whose lowering rate in an in-track position is maximum in the region. The magnetic recording head, whose recording magnetic field is distributed in a rectangular shape, is used in this way so as to form a magnetic bit having a rectangular shape that is suitable for reproduction performed by a common reproduction head having a rectangular reproduction region, thereby improving an S/N of a reproduction signal dramatically.

Abstract: The slider tester is capable of solely testing a slider and securely selecting good sliders so as to reduce wasteful costs. The slider tester, which tests reading and writing functions of a slider for reading data from and writing data on a recording medium, includes a testing device for testing the functions of the slider, and a setting plate holding the slider and electrically connecting the slider to the testing device. The setting plate separates the slider a prescribed distance from the recording medium during the test so as to read data from and write data on the recording medium, wherein the slider can be independently attached to and detached from the setting plate.

Abstract: A system for detecting thermal asperities and magnetic defects on a disc. The system includes a wide write head and a certification head. The wide write head includes a thermal asperity detector and a write element. A method for detecting thermal asperities and magnetic defects comprising writing a track with the wide write head, reading defects with the certification head, and scanning for thermal asperities with the thermal asperity detector. A burst pattern can be written to the disc upon locating a asperity of defect.

Abstract: A method, apparatus, and computer instructions for writing data to a magnetic media. A first frequency is written on a first track on the magnetic media on a first track width. A second frequency is written on the first track in which a combination of the first frequency and the second frequency encodes a bit of data on the first track. An erase pattern is created on a second track on the magnetic media, the second track being adjacent to the first track in which the bit of data on the first track is readable by a tape drive system having a second track width wider than the track width of the first track.

Abstract: In addition to the conventional test pattern writing in a center of each track and inspection of burst patterns (A and B patterns) through a writing test in a SAT, there is also performed a test pattern data writing test, which is done at each boundary between tracks. With this additional test, it is possible to accurately inspect both C and D burst patterns that are sensitive to a PES signal at each boundary between tracks.

Abstract: A system provides two distinct solutions for encoding and decoding servo positioning data for a hard disk drive. A first solution includes: encoding each group of four bits of a pattern signal in a Matched Spectral Null (MSN) format through an intermediate rate 4/6 code; providing a duplicated bit for each bit of the six bit code word obtained with the previous step. A second solution includes: encoding each group of four bit of the pattern signal adding a parity check bit as an intermediate rate ? code; encoding each of the five bits using the biphase map. Both solutions include subsequently: reading a servo wedge information signal using a read and write channel of the hard disk drive; and using a trellis Partial Response decoding scheme matched to the encoded word for obtaining angular and radial information for the head positioning.

Abstract: An apparatus comprising a sampler circuit and a filter circuit. The sampler circuit may be configured to generate a digital signal in response to a pre-amplified signal. The filter circuit may be configured to generate a track ID signal in response to the digital signal. The filter circuit may also be configured to (i) improve or increase signal-to-noise ratio (SNR) and (ii) reject DC offset errors.