Abstract: A controller of a storage device having a user area storing an operating system, the storage device developing the operating system stored in the user area on a host device in accordance with an access from the host device. The controller includes a user authentication routine storage controlling unit that stores a user authentication routine for executing user authentication before startup of the operating system, in a predetermined area inside the user area, and an access controlling unit that permits access to the predetermined area from the host device when the user authentication routine is used, while prohibiting access to the predetermined area from the host device when the user authentication routine is not used.

Abstract: According to one embodiment, a storage device includes an area demodulator and a head position demodulator. The area demodulator demodulates a first demodulation signal and a second demodulation signal having a phase difference of 90° from a read signal by a head of an area demodulation pattern recorded on a medium. The head position demodulator receives the first demodulation signal and the second demodulation signal, and outputs a phase angle indicating a direction of a vector formed in a phase plane by the first demodulation signal and the second demodulation signal as a head position signal.

Abstract: According to one embodiment, an information storage device includes a recording/reproducing head, a positioning controller, a position detector, a storage module, and a position error detector. The position detector detects the position of the recording/reproducing head. The storage module stores servo control filters. The position error detector generates a new position error signal from a target position and the position of the recording/reproducing head when the positioning controller performs positioning control with control current obtained from a position error signal having passed through each servo control filter. Upon occurrence of a recording/reproducing error, learning to calculate a vibration amount from the position of the recording/reproducing head is sequentially performed for the servo control filters for a predetermined time.

Abstract: According to one embodiment, in a disk drive, a voice coil motor is controlled to cause a head to minutely vibrate in a radial direction on a track of a disk. When the voice coil motor vibrates the head in the radial direction of the disk, frictional force occurring between the disk and the head is calculated based on the driving force of the voice coil motor generated to vibrate and detected positional information, thereby measuring frictional characteristics.

Abstract: A suspension device including a flexure with conductors is provided with an anti-ESD section. The anti-ESD section includes a metal plate, a insulating layer, a first electrically conductive member formed of a pair of read conductors, a second electrically conductive member formed of a pair of write conductors, a heater conductor, semiconductive layers, etc. The semiconductive layers are grounded to the metal plate and electrically isolated from one another by an insulating portion.

Abstract: An optical device includes a clad composed of a material having a first refractive index, a core which is embedded in the clad, composed of a material having a second refractive index different from the first refractive index, and tapers toward the end-point thereof, and a light-transmitting layer which is composed of a material different from the material having the second refractive index and cuts across an optical path at the end-point thereof.

Abstract: According to one embodiment, a position control apparatus includes: a digital control module that performs position control including disturbance adaptive control with a predetermined sampling period using a control constant, in accordance with a position error; and a table that stores the control constant corresponding to one of values sin(?T), cos(?T), and sin(?T/2), wherein the digital control module determines a control value of the actuator in accordance with the position error, calculates a value of one of estimated errors of sin(?T), cos(?T), and sin(?T/2) according to an adaptive law from a signal based on the position error, multiplies the calculated estimated error by an adaptive gain in accordance with a value of the angular frequency ?, updates one of the values, reads the corresponding control constant from the table based on the updated value, and updates the control constant.

Abstract: A receiver receives an acoustic wave in an atmospheric pressure measuring apparatus. Since a variation in the intensity of an acoustic wave reflects a variation in the atmospheric pressure, the atmospheric pressure can be measured based on the intensity of the acoustic wave received at the receiver. The atmospheric pressure can in this manner easily be measured with a simplified structure.

Abstract: A control device includes an acquisition section which acquires a reading signal from a head under plural heat amounts, an computation section which computes plural kinds of characteristic values representing characteristics of the reading signal for each of the plural generated heat amounts by using at least one kind of algorithm, a contact determination section which determines whether or not the head contacts the storage medium for each of the two or more kinds of characteristic values based on a change of the characteristic values for the generated heat amount, and an association determination section which determines an association of a distance between the head and the storage medium with the generated heat amount when determined that the head contacts the storage medium for any of the characteristic values as the generated heat amount when the head contacts the storage medium so that the is considered to be zero.

Abstract: According to one embodiment, a storage device includes: ahead actuator configured to move a head to an arbitrary position on a disk medium; a write/read module configured to write data to or read data from the disk medium using the head; an adjustment region selector configured to divide the disk medium into a plurality of regions in a circumferential direction, write test data to each of the regions, read the test data to measure signal quality of the each of the regions, compare the signal quality of the each of the regions, and select a parameter adjustment region; and a parameter adjustment module configured to adjust a parameter used for the write/read module to write data to and read data from the disk medium to an optimal value using the selected parameter adjustment region.

Abstract: A magnetic storage control apparatus for controlling a magnetic storage apparatus that uses a recording medium having a plurality of reference signals on its track and having a data area between the reference signals. The apparatus includes: a measurement section that reproduces the reference signal in a predetermined track of the recording medium and measures, for each data area, the time for a head to scan the data area to obtain a measurement value; a calculation section that calculates a setting value concerning the frequency of a recording clock used in data recording based on the measurement values of a plurality of data areas obtained by the measurement section; and a generation section that generates the recording clock based on the measurement values obtained by the measurement section and setting value calculated by the calculation section.

Abstract: A signal-level calculating unit calculates a signal level based on a gain signal. A sample generating unit associates heater power with the signal level and generates samples used for determining the maximum power. An approximation-line determining unit determines an approximation line of the samples in a two-dimensional coordinate system. A line shifting unit shifts the approximation line and determines a line for determining a signal level when the heater power is increased by one step. A comparative-value calculating unit calculates a comparative value based on the line. An upper-limit determining unit compares the comparative value and an actual signal level, and determines whether the heater power has reached the maximum power.

Abstract: In a position control device having a disturbance suppression function, loop gain is calibrated without stopping disturbance suppression control. The position control device has, for disturbance suppression control, a feedback controller for changing the loop characteristic, a table for storing a target gain according to a disturbance frequency, and a gain calibration section for calibrating open loop gain. The gain is calibrated using a target gain in the table according to the change of the loop characteristic of the feedback controller. Open loop gain can be calibrated without interrupting the disturbance suppression control, so the open loop gain can be accurately calibrated without being affected by disturbance, and accurate position control is possible.

Abstract: A pattern transfer apparatus includes a storage-medium-surface detecting unit that detects a foreign substance or defect on a surface of a storage medium and specifies a position and a size of the foreign substance or defect; a relative-position adjusting unit that adjusts a relative position on a contact surface between the surface of the storage medium and a transfer pattern surface of a transfer master, and a relative-position-adjustment instructing unit that calculates an adjusted value of the relative position according to a detection result, and instructs the relative-position adjusting unit to adjust the relative position based on the adjusted value.

Abstract: A storage device for storing data includes: an interface controller connectable to a host via a interface, the interface controller having an active state capable of transmitting data to the host and an inactive state having a lower power consumption than the active state; a medium for storing data; a head for read out data stored in the medium; and a processor for executing a process including receiving a command for reading out data stored in the medium from the host, determining timing when the data read out from the medium reaches the interface controller, and starting transition of the interface controller from the inactive state into the active state before the determined timing.

Abstract: According to one embodiment, a head slider, includes: a slider body; an insulating nonmagnetic film configured to be laminated on an air outflow side end face of the slider body; a magnetoresistive effect film configured to be buried in the nonmagnetic film; first and second wiring patterns configured to be buried in the nonmagnetic film and connected to the magnetoresistive effect film; a third wiring pattern configured to be buried in the nonmagnetic film and connected to the first and second wiring pattern in parallel to the magnetoresistive effect film; and a switch element configured to be buried in the nonmagnetic film and change conductivity of the third wiring pattern between conduction and non-conduction.

Abstract: An amplifier amplifies, according to a first gain value, a first input signal acquired by reproducing first information from first areas having the first information recorded therein area by area in order. The amplifier also amplifies, according to a second gain value, a second input signal acquired by reproducing second information pursuant to reproduction of the first information, from a second area adjacent to the first area and that has the second information recorded at a recording level different from that of the first information. When the first input signal is amplified, a first gain value following a change in the first signal is calculated so that the level of the amplified signal becomes constant. When the second input signal is amplified, a second gain value following a change in the first gain value is calculated so that the level of the amplified signal becomes constant.

Abstract: Aspects of the present embodiment are related to a power supply voltage supply circuit and the disk apparatus that are capable of reducing power consumption in data writing and reading. The power supply voltage supply circuit includes a data processing unit writing data onto a disk medium and/or reading data from the disk medium=having a plurality of zones assigned a cylinder number, a data input-output unit transmitting data to the data processing unit at a transfer rate in accordance with the zones, a power supply voltage supply unit supplying a voltage to the data input-output unit and a control unit controlling the power supply voltage supply unit in order to supply the voltage in accordance with the transfer rate.

Abstract: According to one embodiment, a magnetic recording apparatus includes: an information recording module configured to record a predetermined number of lines of information with a predetermined length in an information recording region of a magnetic recording medium, each of the lines of information having a same recording start position with respect to a relative movement direction of the magnetic recording medium and a recording element, the each of the lines of information being provided with an overlaying portion of adjacent lines of information. The information recording module is configured to record clock information in one or a plurality of the lines of information.

Abstract: A magnetic disk apparatus that uses a head to write data in a plurality of unit areas arranged in an adjacent relationship to each other on a surface of a magnetic disk, and includes: a first recording section that records, in a RAM, the position of a unit area which is a target of data write; a first counting section that counts the number of times of data write operation performed for the unit area corresponding to the position recorded by the first recording section; and a second recording section that records, in a non-volatile storage medium different from the RAM, the side position which is the position of a unit area adjacent to the unit area whose number of records counted by the first counting section is more than a predetermined value.