Abstract: According to embodiments, a magnetic disk apparatus includes a magnetic disk, a magnetic head, a temperature sensor, and a controller. The magnetic disk has formed therein a servo sector in which servo data including a first post code and a second post code is recorded. In the positioning of the magnetic head, the controller performs a correction using a third post code that is based on the first and second post codes and a first temperature detected by the temperature sensor.

Abstract: According to one embodiment, in a disk device, a controller adjusts a correction value of a radial position of servo track according to a ratio between amplitude of a correction value spectrum of a radial position of the servo track at a first circumferential position and at a second circumferential position when positioning control of the head to a target data track is performed on a basis of servo information read from the servo track. At the first circumferential position, a relative speed of a change in the radial position of the servo track with respect to a radial position of the target data track becomes a first speed. At the second circumferential position, a relative speed of a change in the radial position of the servo track with respect to the radial position of the target data track becomes a second speed.

Abstract: According to embodiments, a magnetic disk apparatus includes a magnetic disk, a magnetic head, a temperature sensor, and a controller. The magnetic disk has formed therein a servo sector in which servo data including a first post code and a second post code is recorded. In the positioning of the magnetic head, the controller performs a correction using a third post code that is based on the first and second post codes and a first temperature detected by the temperature sensor.

Abstract: According to one embodiment, a magnetic disk device includes a magnetic disk, a spindle motor, a magnetic head, a ramp load mechanism, a filter, and a control section. The control section rotates the spindle motor at a second rotating speed for a given period of time at startup of the device, and then loads the magnetic head from the ramp load mechanism to a prescribed position on the magnetic disk. The second rotating speed is higher than a first rotating speed at which the spindle motor is rotated at the magnetic head reads/writes data from/to the magnetic disk.

Abstract: A controller for a magnetic disk device acquires a reproduction signal of servo burst data while moving a magnetic head along data tracks that intersect servo tracks at a plurality of points. The controller acquires correction values for correcting repeatable runout on a per servo sector basis based on the reproduction signal. The correction values include a first correction value, which is a correction value for a servo sector at a position where the data track and the servo track are substantially parallel to each other and a second correction value, which is a correction value fora servo sector at a position where the data track and the servo track are not substantially parallel to each other. The controller adjusts the first correction value based on the second correction value, and writes the correction values including the adjusted first correction value onto a magnetic disk.

Abstract: According to one embodiment, a magnetic disk device includes a magnetic disk, a spindle motor, a magnetic head, a ramp load mechanism, a filter, and a control section. The control section rotates the spindle motor at a second rotating speed for a given period of time at startup of the device, and then loads the magnetic head from the ramp load mechanism to a prescribed position on the magnetic disk. The second rotating speed is higher than a first rotating speed at which the spindle motor is rotated at the magnetic head reads/writes data from/to the magnetic disk.

Abstract: A controller for a magnetic disk device acquires a reproduction signal of servo burst data while moving a magnetic head along data tracks that intersect servo tracks at a plurality of points. The controller acquires correction values for correcting repeatable runout on a per servo sector basis based on the reproduction signal. The correction values include a first correction value, which is a correction value for a servo sector at a position where the data track and the servo track are substantially parallel to each other and a second correction value, which is a correction value fora servo sector at a position where the data track and the servo track are not substantially parallel to each other. The controller adjusts the first correction value based on the second correction value, and writes the correction values including the adjusted first correction value onto a magnetic disk.

Abstract: According to one embodiment, a magnetic disk device including a disk, and a controller which calculates a first corrected value based on a first eccentricity of the disk, and writes a first track based on the first corrected value, wherein when the controller interrupts the process for writing the second track so as to overlap the first track at a first position, the controller measures a second eccentricity of the disk, and compares the first eccentricity with the second eccentricity, and when the first eccentricity is different from the second eccentricity, the controller restarts the process for writing the second track from a second position away from the first position in a radial direction.

Abstract: A magneto-optical recording medium processing apparatus of the present invention limits, via a predetermined current limiting means, the bias current applied to a bias coil during seek, when a seek current is applied to a carriage. In accordance therewith, it is possible to reduce the peak of the sum current, which is the total of the seek current and the bias current, and the current consumption of the entire apparatus can also be curbed. Current limiting means, for example, sets a bias current that is smaller than the specified value of the bias current required at media access time, and sets a bias current value such that the total of the seek current and bias current does not exceed an allowable current.

Abstract: This invention relates to a servo-control method and servo-controller of a memory storage device, as well as the memory storage device, for positioning the reading position of a head on a target position. It suppresses phase lag in the high region while preventing a decrease in follow-ability. This invention comprises a storage medium 72, head 76, actuator 60, detection circuit 48, and control circuit 16. The detection circuit 48 detects the amount of shift between the reading position of the head 76 and a target position. The control circuit 16 performs PID calculation for the shift amount and outputs an instruction value for the actuator 60. There is a limiter 121 for limiting the calculated result of the differential component of this PID calculation to a specified value. Only the high region is limited and the low region is not limited, thus it is possible to suppress phase lag in the high while maintaining follow-ability.

Abstract: A tracking control method carries out a tracking control based on a tracking error signal which indicates an error of a beam spot formed on a recording medium by a light beam from a light source with respect to a track. The tracking control method includes detecting a change in a light emission power of the light source, calculating a correction quantity which is used to correct a shift and/or fluctuation of the tracking error signal generated due to the change in the light emission power, and carrying out a correction by adding the correction quantity to the tracking error signal when the change in the light emission power is detected.

Abstract: A magneto-optical recording medium processing apparatus of the present invention limits, via a predetermined current limiting means, the bias current applied to a bias coil during seek, when a seek current is applied to a carriage. In accordance therewith, it is possible to reduce the peak of the sum current, which is the total of the seek current and the bias current, and the current consumption of the entire apparatus can also be curbed. Current limiting means, for example, sets a bias current that is smaller than the specified value of the bias current required at media access time, and sets a bias current value such that the total of the seek current and bias current does not exceed an allowable current.

Abstract: An offset measuring unit receives a servo error signal E1 in which a change in an offset caused by a change in an amount of reflection light directly appears and which does not pass through a filter, and measures an offset amount in the servo error signal which is caused by a change in the amount of reflection light. A correction amount calculating unit calculates a correction amount to cancel out the offset amount and outputs the correction amount to an offset correcting circuit for an offset generating period so as to perform correction.

Abstract: An offset measuring unit receives a servo error signal E1 in which a change in an offset caused by a change in an amount of reflection light directly appears and which does not pass through a filter, and measures an offset amount in the servo error signal which is caused by a change in the amount of reflection light. A correction amount calculating unit calculates a correction amount to cancel out the offset amount and outputs the correction amount to an offset correcting circuit for an offset generating period so as to perform correction.

Abstract: A correction processing unit for correcting a level fluctuation appearing on a tracking error signal when a laser beam passes an ID area on a medium track during an on-track control is provided. That is, in the correction processing unit, a correction value determined by a correction value determining unit at a correction timing detected by a correction timing discriminating unit is subtracted by a correcting unit from a signal value obtained by sampling and converting the tracking error signal into digital data by an A/D converter at a predetermined period and reading, thereby performing the correction.