MAGNETIC RECORDING MEDIUM, STAMPER RECORDING/REPRODUCING APPARATUS AND METHOD OF MEASURING A PARAMETER

Abstract

Data track pattern regions, in which data track patterns are formed by concave/convex patterns, and servo pattern regions, in which servo patterns are formed by concave/convex patterns, are provided on a magnetic recording medium so as to be alternately disposed in a circumferential direction. At least one predetermined region that differs to the data track pattern regions is provided between two servo pattern regions that are adjacent in a circumferential direction. A concave/convex pattern including a plurality of first convex parts formed continuously in a radial direction is formed in each predetermined region.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention will be explained in more detail below with reference to the attached drawings, wherein:

FIG. 1 is a block diagram showing the construction of a hard disk drive;

FIG. 2 is a plan view of a magnetic disk;

FIG. 3 is a cross-sectional view of the magnetic disk;

FIG. 4 is a cross-sectional view of a stamper;

FIG. 5 is a plan view of data track pattern regions, servo pattern regions, and a measurement region on the magnetic disk;

FIG. 6 is a diagram useful in explaining the sizes of a recording head and a reproducing head on a magnetic head;

FIG. 7 is a diagram useful in explaining the magnetic write width of the recording head and the magnetic read width of the reproducing head on the magnetic head;

FIG. 8 is a cross-sectional view of a preform and the stamper that is useful in explaining the method of manufacturing the magnetic disk;

FIG. 9 is a plan view of the magnetic disk and the magnetic head in a state where a measurement signal has been written in a measurement region in a state where the reproducing head is made on-track;

FIG. 10 is a plan view of the magnetic disk and the magnetic head in a state where measurement signals are being read from convex parts in a measurement region;

FIG. 11 is another plan view of the magnetic disk and the magnetic head in a state where measurement signals are being read from convex parts in the measurement region;

FIG. 12 is a plan view of the magnetic disk and the magnetic head in a state where a measurement signal has been written on a convex part in the measurement region in a state where the recording head is made on-track;

FIG. 13 is a plan view of the magnetic disk and the magnetic head in a state where an AC erase process has been carried out on an outer periphery part and an inner periphery part of a region where a measurement signal was written;

FIG. 14 is a plan view of the magnetic disk and the magnetic head in a state where a measurement signal is being read from a convex part in the measurement region after the AC erase process has been completed;

FIG. 15 is a plan view of another magnetic disk; and

FIG. 16 is a plan view of data track pattern regions, servo pattern regions, and measurement regions on the other magnetic disk.

Claims

1. A magnetic recording medium on which data track pattern regions, in which data track patterns are formed by concave/convex patterns, and servo pattern regions, in which servo patterns are formed by concave/convex patterns, are provided so as to be alternately disposed in a circumferential direction and on which at least one predetermined region that differs to the data track pattern regions is provided, each predetermined region being disposed between two servo pattern regions out of the servo pattern regions that are adjacent in the circumferential direction, wherein a concave/convex pattern including a plurality of first convex parts formed continuously in a radial direction is formed in each predetermined region.

2. A magnetic recording medium according to claim 1, wherein each predetermined region is disposed between a data track pattern region out of the data track pattern regions and a servo pattern region out of the servo pattern regions that is adjacent to the data track pattern region out of the data track pattern regions in the circumferential direction and the concave/convex patterns are formed so that the data track pattern regions, the servo pattern regions, and each predetermined region are respectively continuous in the circumferential direction.

3. A magnetic recording medium according to claim 1, wherein each predetermined region is set on at least one of an inner periphery side and an outer periphery side relative to the data track pattern regions in the radial direction.

4. A magnetic recording medium according to claim 1, wherein the first convex parts are formed so that a diameter of an inscribed circle with a largest diameter out of inscribed circles on protruding end surfaces of the first convex parts is no greater than a diameter of an inscribed circle with a largest diameter out of inscribed circles on protruding end surfaces of second convex parts formed inside the data track pattern regions and inscribed circles on protruding end surfaces of third convex parts formed inside the servo pattern regions.

5. A stamper on which is formed a stamper-side concave/convex pattern corresponding to the concave/convex patterns on a magnetic recording medium according to claim 1.

6. A recording/reproducing apparatus comprising: a magnetic recording medium on which data track pattern regions, in which data track patterns are formed by concave/convex patterns, servo pattern regions, in which servo patterns are formed by concave/convex patterns, and at least one predetermined region, which differs to the data track pattern regions and the servo pattern regions, are provided;a recording head that writes signals on the magnetic recording medium;a reproducing head that reads signals written on the magnetic recording medium; anda control unit that controls writing of the signals by the recording head and reading of the signals by the reproducing head and measures a predetermined parameter for at least one of the recording head and the reproducing head by writing and reading measurement signals on the magnetic recording medium,wherein a concave/convex pattern including a plurality of first convex parts formed continuously in a radial direction is formed in each predetermined region of the magnetic recording medium, andwhen measuring the predetermined parameter, the control unit writes the measurement signals using the recording head on the first convex parts, reads the measurement signals using the reproducing head, and measures the predetermined parameter based on a result of reading the measurement signals.

7. A recording/reproducing apparatus according to claim 6, wherein as measurement of the predetermined parameter, the control unit measures a distance in the radial direction between a center of a length of the recording head in a direction corresponding to the radial direction of the magnetic recording medium and a center of a length of the reproducing head in the direction corresponding to the radial direction.

8. A recording/reproducing apparatus according to claim 6, wherein as measurement of the predetermined parameter, the control unit measures at least one of a magnetic write width of the recording head and a magnetic read width of the reproducing head.

9. A method of measuring a parameter for a recording/reproducing apparatus that includes: a magnetic recording medium on which data track pattern regions, in which data track patterns are formed by concave/convex patterns, servo pattern regions, in which servo patterns are formed by concave/convex patterns, and at least one predetermined region, which differs to the data track pattern regions and the servo pattern regions, are provided and on which a concave/convex pattern including a plurality of first convex parts formed continuously in a radial direction is formed in each predetermined region; and a recording head that writes signals on the magnetic recording medium; and a reproducing head that reads signals written on the magnetic recording medium, the method comprising writing and reading measurement signals on the magnetic recording medium, thereby measuring a predetermined parameter for at least one of the recording head and the reproducing head, wherein:the writing the measurement signals is performed by using the recording head on the first convex parts formed in each predetermined region;the reading the measurement signals is performed by using the reproducing head; andthe measuring the predetermined parameter is performed based on a result of the reading the measurement signals.