Abstract: In a magnetic reading/writing device, a controller derives at each radius of a recording medium a slope of a curve of track-averaged write performance with respect to an adjustment parameter, and determines a first set of fitting coefficients of a first equation approximating the derived slopes in terms of a first variable representing each radius. The controller acquires write performance dependence on a variable representing each of multiple circumferential positions of the medium by measuring track average write performance with respect to the circumferential positions, and determines a second set of fitting coefficients to approximate by a periodic function the acquired dependence in terms of the first variable. The controller corrects a condition value representing the adjustment parameter by subtracting from the condition value an adjustment value obtained from functions calculated with the first and second sets of fitting coefficients.

Abstract: An inspection method and inspection apparatus of a magnetic disk are provided. A gliding test and a certification test are performed at the same time by simultaneously moving a head for the certification test and a head for the gliding test with a heat distortion utilization mechanism (a micro thermal actuator) along a recording surface of the magnetic disk during rotation at a predetermined revolving speed. A flying height of the head for the gliding test is determined according to a revolving speed of the disk. When the flying height of the head for gliding test is determined according to the revolving speed at the certification test, the head for the gliding test is adjusted to a desired height by adjusting a variation of the heat distortion utilization mechanism disposed on the head for the gliding test. The gliding and certification inspections can be performed at the same time.

Abstract: The application discloses a data storage device including one or more data storage media adapted to store data. The data storage device is connected to and powered by a power source of the host system. In the event of a loss of power from the host system, an auxiliary power source is used to power components of the data storage device. For example, an illustrative auxiliary power source uses back electromotive force EMF from a spindle motor of the data storage device. As disclosed, the device includes test circuitry to test a capacity of the auxiliary power source to store data in the event of the loss of power from the host system.

Abstract: The present invention provides an information recording configuration that achieves both difficulty in reading and highly accurate reading. Highly confidential additional information such as encryption key is recorded in a groove signal. During recording of the additional information, a groove signal is recorded that has an amplitude offset setting commensurate with the bit value. During reading of the additional information, a signal R0 with no offset is estimated from a signal R1 read from the groove signal for a predetermined period, after which a difference signal C=R1?R0 is calculated and integrated for each of the predetermined periods so as to determine the direction of the amplitude offset for each period. This process achieves recording and reproduction of additional information that offers enhanced difficulty in reading and highly accurate reading at the same time.

Abstract: A measuring apparatus includes a first connector connected to a storage controller through a second connector of a motherboard. A control circuit receives voltage signals from the storage controller and converts the voltage signals to hard disk drive (HDD) power signals. A detecting circuit includes an AND gate and first to fourth resistors. A first input terminal of the AND gate is grounded through the first resistor and connected to the control circuit through the second resistor. A second input terminal of the AND gate is grounded through the third resistor and connected to the control circuit through the fourth resistor. An output terminal of the AND gate is connected to a measuring pin of the first connector. The AND gate receives the HDD power signals and outputs a power good (PWG) signal to the measuring pin of the first connector to be measured.

Abstract: The method of controlling a defect of a hard disk drive that includes analyzing a defect type by using indexes of error corrected symbols after performing error correction with respect to each of a plurality of symbols and setting a sector as unusable when the sector includes a defect that is determined to be a defect having a defect type that is a hard defect.

Abstract: An optical information record/playback device of the present invention includes: a light source; a current driver for supplying current to the light source; an optical system for condensing light from the light source onto a recording medium; a monitoring section for monitoring light emission power of the light source; a current driver control section for controlling output current of the current driver; and an arithmetic/control section for controlling an operation of the current driver control section. Before recording information, the arithmetic/control section sequentially conducts a first test light-emission to cause the light source to emit light by using a closed loop circuit and a second test light-emission to cause the light source to emit light by using an open loop circuit, and compares first and second sampling values, which are respectively obtained by sampling the outputs of the monitoring section during the first and second test light-emissions.

Abstract: Various embodiments of the present invention provide systems and methods for determining head polarity. As an example, a head polarity detection circuit includes: a first computation circuit, a second computation circuit, and an inversion determination circuit. The first computation circuit is operable to sum an absolute value of each sample of a first subset of a series of data samples corresponding to a first phase of an analog input to yield a first sum, and the second computation circuit is operable to sum an absolute value of each sample of a second subset of the series of data samples corresponding to a second phase of the analog input to yield a second sum. The first phase is more than ninety degrees offset from the second phase.

Abstract: An optical disk device and recording method of recording data on an optical disk by driving a laser light source with a driving current superimposed with a high-frequency current. The device and method includes a controller for disabling tracking servo and establishing conditions for reproducing a signal from a predetermined region of the optical disk, for generating a tracking error signal by superimposing the high-frequency current varied in amplitude on the driving current for the laser light source, for determining an amplitude of the high-frequency current that provides an optimum quality of the generated tracking error signal, and for recording data on the optical disk by applying the driving current for the laser light source superimposed with the high-frequency current of the determined amplitude.

Abstract: A method of generating a 1-beam tracking error signal (TES), an optical pickup device, and an optical disc drive device adopting the method. A light-receiving element receives a single reflection beam and detects an alternating current (AC) component and a direct current (DC) component from each of areas formed on two sides of a data track. A servo unit generates a TES by adding and subtracting the AC component and the DC component.

Abstract: Various embodiments of the present invention provide systems and methods for determining a location of a spiral pattern. As an example, a location detection circuits is discussed that includes: a pattern detection circuit, a computation circuit, and a center determination circuit. The pattern detection circuit is operable to identify a subset of a series of data samples corresponding to a defined pattern, and to indicate a location of the identified subset of the series of data samples. The series of data samples corresponds to a spiral pattern. The computation circuit operable to sum an absolute value of each sample of the subset of the series of data samples to yield a sum. The center determination circuit operable to identify a location of the spiral pattern using the sum.

Abstract: An optical disc device and information recording/reading method for an optical disc in which a recording layer is formed through volume recording by aligning recording tracks, which hold information, in a homogenous recording region that does not internally have a layer defining a recording position. The information recording method includes a step in which a first recording layer forming a complex recording layer is formed by forming a recording track while recording information by focusing a main beam at a predetermined depth position in the recording region, and a step in which a second recording layer forming the complex recording layer is formed by forming a recording track while recording information by focusing the main beam at a depth position that is separated from the first recording layer in a depth direction by a depth offset greater than ? of a wavelength of the main beam.

Abstract: Techniques are provided for controlling the reading of optical data from a master disk in a holographic replication system. Imperfections in the master disk or movement of the disk during a recording process may cause source beams to deviate from target data tracks. In some embodiments, a detector system is used to determine the focus and alignment of the source beams on the master disk, as well as the tilt and rotation of the disk with respect to the holographic replication system. The detector system may detect deviations in the intensity distribution of the reflections of the source beams and generate an error signal corresponding to focusing, tracking, tilt, and/or rotational errors. Servo-mechanical devices may actuate optical components to compensate for such errors.

Abstract: A computing device and method determines a position of a disk when the disk works abnormally. The computer searches out problem disks by determining if each disk included in the just a bundle of disks (JBOD) works normally, and determining if the computer can obtain a serial number of each problem disk. The computer notifies a user of the order number of the problem disk and an order number of the JBOD, in response to a determination that the computer can obtain serial number of the problem disk. The computer obtains the order number of the problem disk by deleting the data of the disk that works normally from the disk table, and notifying the user of the order number of the disk and the order number of the JBOD, in response to a determination that the computer fails to obtain serial number of the problem disk.

Abstract: An optical disk apparatus according to the present invention includes: a drive selector 28 that makes a switch between a setting for sending a drive signal generated by a focus drive generation section 25 to a focus drive section 29, and a setting for sending a drive signal generated by a focus filter 27 to the focus drive section 29; and a lock-in timing detection section 21 that, upon a light amount signal detected by a light amount signal detection section exceeding a predetermined light amount level, determines that an optical spot reaches a vicinity of any of recording layers, and sends to the drive selector 28 a focus lock-in timing instruction for switching to the setting for sending the drive signal generated by the focus filter 27 to the focus drive section 29. Such configuration provides an optical disk apparatus allowing a stable focus lock in operation to be performed without using a layer determination signal when locking a focus into a recording layer of an optical disk.

Abstract: An optical pickup having a first diffractive optical element that acts on light of a specific wavelength, the first diffractive optical element being arranged in an optical path for guiding reflected light from an optical disk to a photodetector. The photodetector comprises a first detector including a first main light receiver divided into a two-by-two square matrix, and a second detector including a second main light receiver divided into a two-by-two square matrix, the second detector being arranged in a row with the first detector. When the light of a specific wavelength is used, zero-order light of the first diffractive optical element is received by the first main light receiver, +first-order light (or ?first-order light) diffracted by the first diffractive optical element is received by the second main light receiver, and a tracking error signal is generated using an output signal from the second main light receiver.

Abstract: Detecting a defect on a storage device is disclosed. Detecting includes receiving a signal read from a storage device, sampling the signal to obtain a set of signal samples, wherein the sampling starts at an arbitrary time, computing a defect value for a defect type using the set of signal samples, comparing the defect value with a threshold associated with the defect type, determining whether there is a defect of the defect type based at least in part on the comparison, and in the event that a defect is detected, outputting an indication associated with the defect.

Abstract: Optimization of tracks on a hard disk includes: determining I/O characteristics for data clusters to be stored on the hard disk; generating a set of solutions for each possible placement configuration; for each solution, calculating a plurality of cost functions using the I/O characteristics for the plurality of data clusters; for each solution, calculating a membership value using the cost function values; for each solution, calculating a fitness value using the membership value; retaining the solutions with the fitness value greater than a predetermined threshold; determining whether at least one stopping condition has been met; if not, adding new solutions to the retained solutions to generate the next set of solutions; and repeating the calculating the membership value, the calculating the fitness value, and the retaining the solutions with the fitness value greater than the predetermined threshold until at least one stopping condition has been met.

Abstract: Approaches for a testing device for selecting a discrete track media (DTM) format for use with a particular head of a hard-disk drive (HDD). The testing device comprises a continuous magnetic-recording disk, rotatably mounted on a spindle, which stores data using a continuous media format. The testing device also comprises a testing module configured to simulate reading data, stored using a discrete track media (DTM) format, from the continuous magnetic-recording medium. Advantageously, testing time and cost is reduced as both discrete track media (DTM) disks and expensive discrete track media (DTM) recording testing hardware are not required to select the optimal a discrete track media (DTM) format for use with a particular head of a hard-disk drive (HDD). In addition, embodiments may be used to optimize features of the tracks of the DTM disk, such as the land to groove ratio.

Abstract: A system in one embodiment includes a disk; a reservoir having a selectively openable cover; a lubricant in the reservoir; and a sensor for detecting an event or condition that triggers opening of the cover. A method in another embodiment includes determining that a trigger event or a trigger condition is occurring or has occurred in a hard disk drive; opening a cover of a lubricant reservoir for allowing egress of lubricant therefrom upon determining that the trigger event or the trigger condition has occurred; and closing the cover of the lubricant reservoir after a period of time. Additional systems and methods are also presented.

Abstract: Embodiments provide an optical disk drive that includes an embedded test medium for testing the optical performance of an optical head in the optical disk drive.

Abstract: According to one embodiment, a magnetic head includes a magnetic core including a main pole, and a return pole opposed to the main pole with a magnetic gap therebetween, and configured to return magnetic flux from the main pole and form a magnetic circuit in conjunction with the main pole, a coil configured to excite magnetic flux in the magnetic circuit, and a nonmagnetic electrically conductive layer formed by disposing only a nonmagnetic material in the magnetic gap between the return pole and an end portion of the main pole on the recording medium side, and configured to electrically connect the main pole and the return pole. The main pole, the nonmagnetic electrically conductive layer, and the return pole are configured to constitute a series electrical circuit.

Abstract: According to one embodiment, a disk drive is provided, which starts reading data at the head thereof, when a sync mark is detected. The disk drive has a read channel that generates a forced SM detection signal if the sync mark cannot be detected because of the occurrence of TA. The read channel starts generating the forced SM detection signal at the end position of a preamble, which is equivalent to the position of the sync mark.

Abstract: An inspection apparatus and method for a magnetic head or a magnetic disk is conducted using a two-carriage method. In particular, the magnetic disk is rotated by a spindle, a test signal is written into the magnetic disk by one magnetic head mounted in one carriage which moves in the radius direction of the magnetic disk, and the test signal of the magnetic disk is read by the other magnetic head mounted in the other carriage which moves in the radius direction of the magnetic disk to inspect the performance of the magnetic head or the magnetic disk using the read signal. The sector pulses to determine servo timing at which servo burst signals preliminarily written into the disk are read are formed on the basis of a clock signal and an index signal generated along with the rotation of the spindle.

Abstract: A data recovery device including an analog to digital converter (ADC), a filtering-equalizing unit, a zero crossing detector, a data phase locked loop, a data mapping unit and an estimation unit is provided. The ADC converts a radio frequency signal to a plurality of sampling data points. The sampling data points are converted to a plurality of retiming data points and a clock signal by the filtering-equalizing unit, the zero crossing detector and the data phase locked loop. The data mapping unit selects a plurality of maximum data points and minimum data points from the returning data points, and determines whether to map the maximum data points and the minimum data points to other levels for partially reconstructing the retiming data points. The estimation unit recovers the reconstructed retiming data points to a modulation signal.

Abstract: A device and method for reducing power consumption of an optical drive are proposed. The present invention samples a carrier control signal and then compares the samples of the signals with predetermined threshold signals. According to the comparison result, the present invention produces at least one diphase excitation control signal. The diphase excitation control signal comprises at least one impulse signal, and a negative edge of the impulse signal is adjusted to a predetermined level during the period of the diphase excitation control signal. The present invention reduces the time for outputting the control signals and greatly reduces the power consumption of the optical drive thereby.

Abstract: A method for evaluating a read signal obtained by irradiating a medium with a laser beam through an objective lens and reading data from the reflected laser beam by a PRML detection method is provided. The method includes: a sampling step of sampling the data obtained from the reflected laser beam at clock timings to obtain sampled values; and a step of, when a constraint length of a PR class in the PRML detection method is an even number, computing an intermediate sampled value for evaluation using at least adjacent two of the sampled values arranged in the order sampled at the clock timings. The provided method is an objective evaluation method when the PRML detection method is used, whereby the selection of a recording medium and a reading apparatus is facilitated.

Abstract: Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is discussed that includes: a data buffer, an inter-track interference response circuit, an inter-track interference signal estimator circuit, and a sync mark detector circuit. The data buffer is operable to store a previous track data set that includes a first sync pattern. The inter-track interference response circuit is operable to estimate an inter-track interference response from the previous track data set based at least in part on the previous track data set and a current track data set. The current track data set includes a second sync pattern. The inter-track interference signal estimator circuit is operable to calculate an inter-track interference from the previous track data set based at least in part on the previous track data set and the inter-track interference response from the previous track data set.

Abstract: A control method of an optical disc drive includes steps of: detecting data transmission is being performed between the computer system and the optical disc drive or not; stopping supplying an operating voltage to the optical disc drive if data transmission not being performed; determining whether or not an eject switch is being pressed according to a variation in potential on a shared line when a first logic level is detected, and supplying the operating voltage to the optical disc drive if a press on the eject switch is detected and after a predetermined time ejecting a tray from the optical disc drive; and determining whether or not the tray is loaded into the optical disc drive according to a variation in potential on the shared line when a second logic level is detected, and supplying the operating voltage to the optical disc drive if the tray is loaded.

Abstract: An inspection device or inspection method for a magnetic head or magnetic disc which can form a servo pattern applicable to a write system, and a magnetic disc recording device or magnetic disc recording method. In inspection or recording of a magnetic disc, which rotates the magnetic disc, a servo pattern is written into a servo pattern region of the magnetic disc by a write-in element of a magnetic head, and is read by a read-in element of the magnetic head. Servo following of a position of the magnetic head on the magnetic disc is performed based on the servo pattern which comprises a plurality of patterns. The patterns are written-in with a first frequency for causing the patterns to be subjected to the servo following and, the patterns are overwritten with a second frequency different from the first frequency, except a servo following width used in the servo following.

Abstract: An information processing apparatus includes: a signal reproduction section configured to obtain a reproduced signal from a recording medium by radiating a laser beam emitted by a laser-beam source to the recording medium; and a high-frequency signal superposition section configured to superpose either a first high-frequency signal or a second high-frequency signal having a frequency higher than the frequency of the first high-frequency signal on a driving signal used for driving the laser-beam source, wherein, in a first signal reproduction operation, the high-frequency signal superposition section superposes the first high-frequency signal on the driving signal whereas, in a second signal reproduction operation to measure information on the amplitude of the reproduced signal, the high-frequency signal superposition section superposes the second high-frequency signal on the driving signal.

Abstract: Provided are an optical disc discrimination method, an optical disc device and an integrated circuit that enable to accurately discriminate the type of an optical disc. The optical disc discrimination method comprises a first seeking step (S3) of performing a seek operation to a predetermined reference address in a user data area; a second seeking step (S5) of performing a seek operation from the reference address sought in the first seeking step (S3) to a predetermined target address in a physical information area, an address reading step (S7) of reading a current address at a position sought in the second seeking step (S5), and an optical disc type determination step (S8 through S10) of determining the type of the optical disc loaded in the optical disc device, based on the current address read in the address reading step (S7).

Abstract: In general, a test slot is engaged with automated machinery to inhibit movement of the test slot, thereby inhibiting transmission of vibration from the test slot to its surroundings. While the automated machinery is engaged with the test slot, the automated machinery is actuated to insert a storage device into the test slot, or remove the storage device from the test slot.

Abstract: A method and apparatus for compensating for a disturbance by detecting a periodic external disturbance applied to a data storage apparatus is provided. The method includes: calculating a correlation coefficient for a first signal corresponding to a first period and a second period that is adjacent to the first period generated from a servo control system of a data storage apparatus; estimating a disturbance of a third period by using the first signal of the first period; determining whether a periodic external shock is generated based on the calculated correlation coefficient; and if it is determined that the periodic external shock is generated, compensating for the disturbance to be generated in the third period by feed-forwarding the estimated disturbance of the third period to the servo control system.

Abstract: Disclosed are a method and system for distinguishing spatial and thermal defects on perpendicular media. The magnetic domains of the perpendicular media are oriented to have a first polarity, scanned using a read head, oriented to have a second polarity and scanned again. The signals from the read head are combined to produce output signals having improved signal to noise ratios from which the locations of spatial and thermal defects can be identified and distinguished.

Abstract: One way to minimize full DC head-skew re-calibrations rendered necessary by changes in storage media drive operating temperature is to compensate for temperature-induced DC head-skew using a known relationship between temperature-induced DC head-skew and storage media operating temperature. More specifically, a first DC head-skew is measured at a first arbitrary temperature of the storage media drive. A second DC head-skew is measured at a second arbitrary temperature of the storage media drive. A DC head-skew correction factor is calculated using the first and second DC head-skews at the first and second arbitrary temperatures. When a multi-head storage media drive is powered-up for operation, a temperature sensor located in the storage media drive assembly measures the current storage media drive temperature. The head-skew correction factor is applied based on the measured temperature to correct the DC head-skew.

Abstract: This invention relates to a system and method performed by a controller in a hard disc drive to generate a write fault signal. The system performs in the following manner. The system begins by receiving a sample of a position error signal. The system then generates a control signal from the position error signal. A sample of the control signal is then captured by the system. The system then determines a parameter to test from the captured sample of the control signal. The absolute value of the parameter is then calculated and compared to a threshold value. The system then generates a write fault error signal in response to a determination that the absolute value of the parameter is greater than or equal to the threshold value.

Abstract: The present application is directed to a slider supporting apparatus for flying a slider of a hard disk drive in the manufacturing process to provide electrical performance characteristics. The present invention discloses an integrated design including the electrical interconnect, the gimballing mechanism, the preload mechanism and the slider supporting mechanism integrated into a single supporting structure.

Abstract: In a disk drive, a method for servo burst-decoding demodulation that accommodates track pitch variation. Depending on the distance a read head is displaced from a read head target position, a target-based blending scheme, a position-based blending scheme, or a weighted combination of both is used to determine the position of the transducer head. When the transducer head is relatively close to the target position, the target-based blending scheme is used to decode servo bursts and calculate the exact head position. When the transducer head is relatively far from the target position, the position-based blending scheme is used to decode servo bursts and calculate head position. When the transducer head is an intermediate distance from the target position, a weighted combination of the target-based and position-based blending schemes is used.

Abstract: Various embodiments of the present invention provide systems and methods for servo data based harmonics calculation. For example, a method for calculating harmonics is disclosed that includes: providing a data processing circuit; receiving a first data set derived from a data source during a servo data processing period; performing a first harmonics calculation using the first data set to yield a first harmonics ratio; receiving a second data set derived from a source other than the previously mentioned data source during a user data processing period; performing a second harmonics calculation using the second data set to yield a second harmonics ratio; and calculating a ratio of the first harmonics ratio to the second harmonics ratio.

Abstract: Methods and apparatus are provided for gain estimation using servo data with improved bias correction. The gain is estimated using a preamble in a servo sector by obtaining a first gain estimate using a first gain estimation algorithm (such as a Zero Gain Start Algorithm) and a first portion of the preamble; storing the first portion of the preamble in a memory buffer; obtaining a second gain estimate using a second gain estimation algorithm (such as a Zero Forcing algorithm) and the first portion of the preamble; and processing Servo Address Mark (SAM) and Gray data in the servo sector using the first gain estimate substantially simultaneous to the step of obtaining the second gain estimate. A gain error can be obtained by calculating a difference between the first gain estimate and the second gain estimate. The gain error can be used in burst processing of the servo data.

Abstract: In order to enable a highly-sensitive certifying test by detecting a signal with a high S/N ratio while controlling the glide height of a magnetic head to be optimized at the time of the certifying test, a method for inspecting a magnetic disk by conducting the certifying test for the magnetic disk using the magnetic head incorporating a heater includes: writing data into the magnetic disk using the magnetic head; and reading the data written into the magnetic disk using the magnetic head. Electric power applied to the heater incorporated in the magnetic head is switched between when writing the data and when reading the data.

Abstract: In one embodiment, there is provided a magnetic disk apparatus. The apparatus includes: a recording medium including a recording surface for recording information; a slider including a head configured to write information to the recording medium or read information from the recording medium; and a controller configured to control moving of the slider so as to remove a substance adhered to the slider and such that the slider is stopped at a position where the slider and the recording surface of the recording medium do not interfere with each other after the slider is moved at a given velocity or acceleration.

Abstract: An apparatus comprising a write circuit, a processing circuit and a monitor circuit. The write circuit may be configured to generate one or more write control signals in response to an input signal. The processing circuit may be configured to generate an intermediate control signal in response to (i) the input signal, (ii) a reference clock signal and (iii) one or more user input signals. The monitor circuit may be configured to generate a sample signal in response to (i) the write control signals and (ii) the intermediate signal. The sample signal may represent a waveshape of the write control signals used to monitor writing to a data storage system.

Abstract: A method for measuring noise of a magnetic head includes setting a plurality of threshold values, applying bias current or voltage to a read element of the magnetic head, applying an external transverse magnetic field to the magnetic head, amplifying output signal from the read element to produce an amplified signal, filtering the amplified signal to produce a filtered signal, generating an enable signal for each threshold value in a predetermined time window by a counting control means with input signals which include the filtered signal and the threshold value, measuring the cumulative time duration of each enable signal, making an amplitude-duration distribution according to the cumulative time durations and the threshold values, calculating a plurality of parameters according to the amplitude-duration distribution and analyzing the parameters with a plurality of predetermined criteria to determine the defects of the magnetic head.

Abstract: Provided are a method, servo channel, and tape drive for determining a reference waveform used by a correlator in a servo channel. Sequences of servo signal samples are provided from read servo signals read from a servo pattern on a recording medium. A determination is made of a reference waveform based on the sequences of servo signal samples and the reference waveform is forwarded. Interpolated servo signals are generated. The interpolated servo signal samples and the forwarded reference waveform are received to generate correlation output samples. Position and velocity information are calculated from the correlation output samples.

Abstract: The present application is directed to a slider supporting apparatus for flying a slider of a hard disk drive in the manufacturing process to provide electrical performance characteristics. The present invention discloses an integrated design including the electrical interconnect, the gimballing mechanism, the preload mechanism and the slider supporting mechanism integrated into a single supporting structure.

Abstract: The present application is directed to a slider supporting apparatus for flying a slider of a hard disk drive in the manufacturing process to provide electrical performance characteristics. The present invention discloses an integrated design including the electrical interconnect, the gimballing mechanism, the preload mechanism and the slider supporting mechanism integrated into a single supporting structure.

Abstract: According to one embodiment, a magnetic disk drive includes a grouping module and a refresh controller. The grouping module partitions a set of tracks on a disk into a plurality of groups. Each of the plurality of groups includes a plurality of tracks including at least two tracks with nonconsecutive physical positions. The refresh controller controls refresh process for each of the plurality of groups.

Abstract: According to one embodiment, there is provided a magnetic recording apparatus including a head slider including read and write elements, and a magnetic recording medium including magnetically recordable recording tracks with a width L1, a wide land track with a width L2 larger than the width L1 of the recording track, and non-recording sections with a width G1 each provided between adjacent recording tracks. The width L1 of the recording track is smaller than a bottom read width BRW of the read and write elements, and the width L2 of the wide land track is larger than the bottom read width BRW of the read and write elements.