Measuring method, manufacturing method for magnetic disk device, and magnetic disk device
AssigneeKabushiki Kaisha Toshiba
InventorToshitaka Matsunaga
Life of this patent
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Abstract
According to one embodiment, a measurement method is applied to a disk device including a disk, and a head configured to protrude toward the disk when power is supplied thereto. In the method, a reference value for each of areas of the disk is acquired from a measurement-value distribution including pre-measured values that correspond to power supplied to a heater when the head is brought into contact with the disk. In each area, a data group calculated from the distribution and the reference value is acquired. An area where the data group has lower values than in the other areas is selected as a first area to be firstly measured. An area to be measured subsequent to the first area based on the data group is selected.
Claims20
A measurement method for use in a disk device comprising a disk, and a head configured to protrude toward the disk when power is supplied to a heater, the method comprising:
- acquiring a reference value for each of a plurality of areas into which the disk is divided, from a measurement-value distribution including a plurality of measured values measured by a measurement in advance, the measurement including measuring a value corresponding to power supplied to the heater when the head contact with the disk;
- acquiring, in each of the plurality of areas, a groups of data calculated based on the measurement-value distribution and the acquired reference value;
- referring to the groups of data corresponding to each of the plurality of areas, and selecting, from the plurality of areas as a first area to be firstly subjected to the measurement, an area where the groups of data has lower values than in other areas;
- and
- selecting an area to be subjected to the measurement subsequent to the first area based on the groups of data in each areas.
A method of manufacturing a magnetic disk device comprising a disk, a head configured to protrude toward the disk when power is supplied to a heater, a memory, and a controller configured to control a flying height of the head during read and write, referring to data stored in the memory, the method comprising:
- acquiring a reference value for each of a plurality of areas into which the disk is divided, from a measurement-value distribution including a plurality of measured values measured by a measurement in advance, the measurement including measuring a value corresponding to power supplied to the heater when the head contact with the disk;
- acquiring, in each of the plurality of areas, a groups of data calculated based on the measurement-value distribution and the acquired reference value;
- referring to the groups of data corresponding to each of the plurality of areas, and selecting, from the plurality of areas as a first area to be firstly subjected to the measurement, an area where the groups of data has lower values than in other areas;
- and
- storing the acquired reference value and data regarding to the first area in the memory.
A magnetic disk device comprising:
- a disk;
- a head configured to protrude toward the disk when power is supplied to a heater;
- and
- a controller configured to:
- acquire a reference value for each of a plurality of areas into which the disk is divided, from a measurement-value distribution including a plurality of measured values measured in advance, the measurement including measuring a value corresponding to power supplied to the heater when the head contact with the disk;
- acquire a groups of data calculated based on the measurement-value distribution and the acquired reference value;
- refer to the groups of data to select, from the plurality of areas as a first area to be firstly subjected to the measurement, an area where the groups of data has lower values than in other areas;
- execute, on all of the plurality of areas, processing of selecting one of two non-selected areas adjacent to a composite area including the already-selected area;
- and
- set, for the plurality of areas, an order of the measurement executed in an order of selection.
Dependencies are inferred from the claim text.