JP2000048352A - Disk storage medium and disk storage device using the medium and production of disk storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk storage medium which permits the strict detection of the positional relations between a head and individual memory cells and permits high-density recording, and a disk storage device using the same and a process for producing this disk storage device. SOLUTION: The disk storage medium constituted with a data storage region 14 by arranging the data storage cells 12 at a prescribed pitch in a track traveling direction is provided with header regions 15 constituted by arranging header cells 13b in the track traveling direction at a pitch of (n) (n is an integer of >=2) times the arrangement pitch in the track traveling direction of the data storage cells 12 at each of the specified rotating angles of the respective tracks, by which the reproducing of the signals of the periods of (n) times the arrangement pitch in the track traveling direction of the data storage cells 12 is made possible. The formation of the clock corresponding to the data storage cells 12 is thereby made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a disk storage medium capable of high-density recording, a disk storage device using the same, and a method of manufacturing the disk storage device.

[0002]

2. Description of the Related Art In a conventional disk storage device using a disk storage medium, for example, a magnetic disk device, a medium on which nothing is recorded is first incorporated into a spindle, and the medium is incorporated into the device based on an external position reference. The position information signal is recorded over all the tracks using the built-in head, and in the actual use state thereafter, the position information signal is reproduced to detect the positional relationship between the head and the track on the medium,
Positioning was being performed.

As described above, by recording and reproducing the position information in a state where the disk drive is incorporated in the apparatus, a large number of disk storage media are stacked and incorporated, and a head is provided corresponding to each medium or the front and back surfaces of each medium. Even if you place
The positional relationship between the head and the track on each medium surface was always constant. Even if the center of the medium was physically deviated from the center of rotation of the spindle, there was no problem and the cylinder configuration could be easily adopted.

[0004]

However, in order to increase the linear storage density (recording density in the concentric track direction) in order to increase the storage capacity per unit area of the disk storage medium, the conventional magnetic recording medium In this case, the magnetization reversal interval for storing information becomes shorter, and the magnetization transition region becomes blurred (reduced resolution) due to the exchange interaction of the magnetic material.
A position shift occurs (non-linear transi
For example, there is a drawback that the reliability of the information is reduced due to the shift of the information.

Therefore, in order to further reduce the magnetization reversal interval and increase the storage capacity per unit area, a mechanical (physical) clearance (gap) is provided between tracks and between storage bits. A so-called patterned medium (Pate) having a structure in which a magnetic body is made independent of each storage cell.
rned Media) has been proposed.

However, in a patterned medium, information can be accurately stored because the storage cells are mechanically formed. On the other hand, when recording is performed, the positional relationship between the magnetic head and each storage cell on the medium is accurately determined. Otherwise, information cannot be stored in a given cell.

In a conventional magnetic disk device or the like, it is sufficient to record the information recording start position as a header and record the information following the header. Therefore, such a strict positional relationship between the head and the medium is not required. However, it has been found that a patterned medium requires a strict positional relationship between the head and the medium (more precisely, individual storage cells on the medium), and therefore, it is not possible to construct an apparatus by merely replacing the conventional medium. .

In order to solve this problem, if an attempt is made to position the head and the medium from the rotation angle using a spindle with high rotation accuracy, an extremely expensive spindle with a controlled medium deflection is required, or the rotation speed is reduced. There was a disadvantage that it was not possible to increase the height.

An object of the present invention is to provide a disk storage medium capable of strictly detecting the positional relationship between a head and an individual storage cell and enabling high-density recording, a disk storage device using the same, and a disk storage device. It is to provide a manufacturing method of.

[0010]

According to the present invention, in order to achieve the above object, in a disk storage medium in which a plurality of tracks for recording and reproduction are arranged in a ring, each track records and reproduces arbitrary information. And a reference magnetic area for indicating a predetermined position in the track running direction. The information storage area is separated from an adjacent track in the track width direction, and is mutually separated in the track running direction. It is configured by arranging data storage cells composed of minute isolated magnetic material cells that are divided and are the minimum unit for recording and reproduction at a predetermined pitch in the track traveling direction,
The reference magnetic regions are separated from each other in the track width direction, and are also separated from each other in the track running direction. It is characterized by being arranged at a pitch of n (n is an integer of 2 or more) times the arrangement pitch in the direction.

According to the above configuration, a signal having a cycle of n times the arrangement pitch of the data storage cells in the information storage area in the track running direction can be reproduced from the header cells in the reference magnetic material area. A corresponding clock can be created, and recording / reproduction strictly corresponding to the position of each memory cell can be performed.

At this time, if the ratio of the length of the header cell in the track running direction to the gap between the header cells adjacent in the track running direction is 1: 1, the entire storage medium is subjected to DC demagnetization (magnetization). Thus, a signal having a large amplitude can be reproduced only from the cells in the reference magnetic material region.

Further, if the length of the header cells in the track width direction is less than half the track pitch, and the header cells adjacent in the track running direction are alternately arranged on the right or left side of the center in the track width direction, It is possible to reproduce a signal whose amplitude changes in accordance with the arrangement of header cells in the track width direction as well as the track running direction, that is, the tracking of the magnetic head, and also enables tracking control.

The header cells are arranged in the track width direction so as to be shifted by a half track pitch with respect to the tracks in the information storage area, and in the track running direction, between adjacent tracks in the track running direction of the header cells. Even in the case where the arrangement is shifted by half the arrangement pitch, a signal whose amplitude changes according to the tracking of the magnetic head can be reproduced in the same manner as described above. At this time, if the ratio of the length of the header cell in the track running direction to the gap between the header cell and the adjacent header cell in the track running direction is 1: 3, the entire storage medium is demagnetized by direct current so that the reference magnetic field can be obtained. Similarly, a signal having a large amplitude can be reproduced only from cells in the body region.

Further, a disk storage device using the disk storage medium in which at least the header cell is DC-magnetized, converts a signal of a period corresponding to a reference magnetic region from a reproduction signal corresponding to an arbitrary track of the disk storage medium. Extracting means, means for reproducing a first clock corresponding to an arrangement pitch corresponding to a track of an information storage area of a header cell from the signal, and multiplying the first clock by n to obtain an arrangement pitch of a data storage cell. Means for generating a corresponding second clock, and recording / reproducing with respect to the data storage cell of the information storage area using the second clock.

Further, in this disk storage device, a rotation driving means for driving the disk storage medium to rotate and outputting information of a reference position and a rotation angle of the rotation; Storage means for storing a relationship with the position of the body region; information on the reference position and the rotation angle of the rotation; and a relationship between the stored reference position of the rotation and the position of the reference magnetic region on the disk storage medium. Means for generating a signal corresponding to the position of the reference magnetic material region.

In these disk storage devices, the phase difference at which the maximum reproduction output is obtained when recording is performed on the data storage cell with the alternating current while changing the phase of the second clock is stored. 2 storage means, wherein a second clock is created from the first clock and the phase difference.

Further, in these disk storage devices, there is provided a means for dividing a reproduction signal in a period corresponding to the reference magnetic material region at a cycle twice as long as the second clock, and comparing the two to obtain tracking control information. It is characterized by having.

Furthermore, in these disk storage devices, the step of incorporating the disk storage medium into the rotation drive means of the disk storage device, the step of DC degaussing the disk storage medium, and the step of reproducing the DC degaussed disk storage medium Storing a relation between the position and a reference position of rotation obtained from the rotation drive means in the storage means, as a position of the reference magnetic material area on the disk storage medium, during which a signal of a predetermined level or more is obtained; And repeating the recording and reproduction of the data storage cell with the alternating current while changing the phase of the second clock, and storing the phase difference at which the maximum reproduction output is obtained in the second storage means. be able to.

[0020]

FIG. 1 shows an embodiment of a disk storage device according to the present invention, in which 10 is a disk storage medium, 21 is a magnetic head, 22 is a spindle,
3 is an actuator, 24 is a recording / reproducing circuit, 25 is a rotation timing generator, 26 is a timing phase information memory (ROM), 27 is a switch, and 28 is a bandpass filter (BP).
F), 29 is a waveform shaper, 30 is a phase locked oscillator (PL)
L), 31 is a recording pattern generator, 32 is a clock phase information memory (ROM), 33 is a tracking error amplifier, 34 is a tracking control circuit, and 35 is a servo amplifier.

FIG. 2 shows an example of an embodiment of the disk storage medium 10 of the present invention, in which a part of the surface of the medium is enlarged together with a magnetic head (schematically). 11 is a media substrate, 12 is a data storage cell, 1
3 is a header cell.

The data storage cell 12 is composed of minute isolated magnetic cells which are separated from adjacent tracks in the track width direction and are also separated from each other in the track running direction and are the minimum unit for recording and reproduction. , Medium substrate 11
Above, they are arranged at a predetermined pitch in the concentric track running direction, and constitute an information storage area (hereinafter referred to as a data storage area) 14 for recording and reproducing arbitrary information. The header cells 13 are composed of minute isolated magnetic cells separated from each other in the track width direction and also separated from each other in the track running direction. A reference magnetic region (hereinafter referred to as a header region) which is arranged at a pitch of n times (n is an integer of 2 or more) times the arrangement pitch of the data storage cells 12 in the track traveling direction and indicates a predetermined position in the track traveling direction 15). Here, the ratio of the length l ₁ of the header cell 13 in the track running direction to the gap l ₂ between the header cells 13 adjacent in the track running direction is set to 1: 1.

A plurality of data storage areas 14 and header areas 15 are alternately arranged on each track. Particularly, the header area 15 is provided at every fixed rotation angle of each track similarly to the case of the conventional servo sector. Arrangement
Is formed.

FIG. 3 shows another embodiment of the disk storage medium 10 according to the present invention, in which a header cell has a structure capable of extracting a signal for tracking control.

That is, in the figure, reference numeral 13a denotes a header cell whose length in the track width direction is equal to or less than half the track pitch, and each header cell 13a adjacent in the track running direction is located at the center (in the figure) in the track width direction. (Indicated by a dash-dot line in the middle).
Other configurations are the same as those in FIG. FIG. 4 shows still another example of the embodiment of the disk storage medium 10 of the present invention, here, another example in which a header cell has a structure capable of extracting a signal for tracking control.

That is, in the figure, reference numeral 13b denotes a header cell which is arranged at a half track pitch offset from the track of the data storage area 14 in the track width direction, and is located between adjacent tracks in the track running direction. Are shifted from each other by half the arrangement pitch in the track running direction.

Here, header cell 1 on the same track
The ratio of the length l ₁ of the track 3b in the track running direction to the gap l ₂ ′ to the header cell 13b adjacent in the track running direction is set to 1: 3. When correctly tracked above, the ratio of the header cell length to the gap in the header area 15 is 1: 1 as in the example of FIGS.
Becomes Other configurations are the same as those in FIG.

Hereinafter, the disk storage medium 10 will be described using an example shown in FIG.

In FIG. 4, the arrow A indicates the direction of relative movement between the medium 10 and the magnetic head 21. The medium 10 is rotated via the spindle 22 so that the magnetic head 21 and the medium 10 maintain a small gap. Relative movement, the data storage cell 12 and the header cell 1 under the magnetic head 21.
3b will pass.

Here, when the medium 10 is entirely DC-demagnetized (magnetized) in one direction, the magnetization becomes as shown in FIG. 5 (a). Needless to say, if the magnetic material has in-plane anisotropy, it is magnetized along the track direction, and if it has perpendicular anisotropy, it is magnetized perpendicular to the medium surface.

When the medium 10 is reproduced by the magnetic head 21, small signals are hardly detected in the normal data storage area 14 because small magnetic cells formed by the data storage cells 12 are arranged in a certain direction as shown in FIG. 5B. However, since the pitch of the magnetic material is large in the header region 15 having a large magnetization cell, a signal having a cycle corresponding to the header cell 13b is detected.

That is, the pitch of the data storage cell 12 is set to T _D
The output E when each data storage cell 12 is alternately reversed in magnetization direction and stored is the shortest magnetization reversal interval becomes the solitary wave output E ₀ when the magnetization reversal interval is sufficiently long. for electromagnetic parameters such as half compared, the relationship between the output E and the magnetization reversal interval is expressed as _{E / E 0 = (a /} T D) π · cosech (aπ / T D) ( where, a is a constant).

Therefore, for example, if the pitch T _H of the header cell 13b is set to four times T _D , the output of the header region 15 is equivalent to the output at the time of the shortest magnetization reversal even in the DC magnetization state. At this time, if the ratio of the length of the magnetic material cell to the gap in the data storage area 14 is 1: 1, the output in the DC magnetization state is about 1/20 of the solitary wave output, and is hardly detected.

A signal indicating the position (period) of each of the plurality of header areas 15 on the medium 10 can be created using the signal detected from the header area 15.

Specifically, in the apparatus shown in FIG. 1, the rotation angle information output from the spindle 22 is also based on the timing at which the information on the reference position (index) of rotation of the medium 10 from the spindle 22 is output. (For example, encoder pulses), and the recording / reproducing circuit 2
4, when a reproduction signal of a predetermined level or more is obtained, a count value (rotation angle information) corresponding to the start and end of the period (that is, the period corresponding to the header area) is obtained, and this is stored in the ROM 26 in advance. After that, from the information of the index and the rotation angle obtained from the spindle 22 and the information stored in the ROM 26,
The rotation timing generator 25 can generate a signal (gate signal) corresponding to the period of each header area.

On the other hand, a clock obtained by the detected signal from the header region 15 and the waveform shaping (header clock), only the ratio n between the pitch T _H of the pitch T _D and the header cell 13b of the data storage cell 12 described above When multiplied, a clock whose cycle matches the pitch of the data storage cells 12 can be created.

More specifically, in the apparatus shown in FIG. 1, the switching area of the header area 15 is controlled by the switching section 27 which is switched from the reproduction signal of the recording / reproduction circuit 24 based on the gate signal from the rotation timing generator 25 described above. , The noise and the like are removed by the bandpass filter 28, the waveform is shaped by the waveform shaper 29 to obtain a header clock, and the header clock is multiplied by n by the PLL 30 to obtain the data storage cell. A clock corresponding to 12 pitches can be created.

This clock is input to the recording pattern generator 31 to which the alternating signal has been input as the recording data input.
When recording is performed on the portion where the header signal is not detected via the recording / reproducing circuit 24 and the magnetic head 21, that is, on the data storage portion 14, the magnetization pattern such that the magnetization reversal occurs at a predetermined timing as shown in FIG. That is, a magnetization pattern in which magnetization reversal occurs between data storage cells is obtained. FIG. 5D shows a reproduced signal corresponding to the magnetization pattern at this time. In this case, normal information can be stored by recording normal random data instead of an alternating signal as a recording data input.

Actually, a clock obtained by multiplying the header clock by n and the data storage cell 12 on the medium 10 are used.
Means that the periods are the same, but the phase is not guaranteed. In other words, when the current reversal of the magnetic head to cause the magnetization reversal occurs in the gap between the data storage cell and the adjacent data storage cell, the current waveform can be faithfully stored, but when the current reversal occurs at the center of the data storage cell. Since the magnetization of the data storage cell is canceled by
It does not become the magnetization pattern to be recorded and will be recorded erroneously.

Therefore, in the present invention, the phase is adjusted as follows. That is, when recording is performed in the data storage area 14 using an alternating current that causes the largest output fluctuation while changing the clock phase, the reproduced output changes as shown in FIG. At this time, a phase difference (a correction value in the PLL corresponding to the phase difference) when the reproduction output is maximized from the obtained data is stored in the ROM 32.

At the time of actual information storage, the ROM 26 described above is used.
The recording / reproducing operation is switched by the gate signal generated from the rotation timing generator 25 based on the information on the rotation angle corresponding to the header area stored in the header area so that the header area is always reproduced.
This is performed by generating a clock in the PLL 30 from the information of the phase difference stored in 2.

The ROM 26 and ROM 32 described above are used.
The operation of writing information into the medium only needs to be performed once before shipment of the apparatus. When there are a plurality of recording surfaces and / or media on the medium and there is a head combined with each recording surface, RO
In M26, information is recorded corresponding to the type of zone setting of the header area on each recording surface (setting of the number of header areas provided in one track, setting of angle) (when the zone setting is 1).
However, in the case of the type, there is only one), but the ROM 32 stores information corresponding to each combination of the head and the recording surface. Although a variable timing generator required for writing information to the ROM 32 becomes large, it is used only in a manufacturing factory or the like before the device is shipped. Simply reading the phase difference information corresponding to the combination of the recording surfaces from the ROM 32 and shifting the phase of the clock reduces the amount of hardware and hardly affects the device cost, so there is no restriction on performance.

By the way, the amplitude of each signal of the cycle corresponding to the header cell 13b shown in FIG. 5B or 5D corresponds to the area of the header cell 13b with respect to the locus drawn by the magnetic head 21 on the medium surface. I do. Therefore, when the magnetic head 21 accurately tracks the track center (the dashed line in the figure) of the data storage area 14, the area of each header cell 13b with respect to the locus is the same, and the amplitude of each signal is also the same. However, if the tracking position is shifted to the left or right, the header cell 13b located on the right side of the track center and the header cell 13b located on the left side will have different areas, and the amplitude of the signal described above will be different. Alternately change, that is, alternately change in magnitude.

Therefore, by alternately cutting and comparing and amplifying a signal having a cycle corresponding to the header cell 13b,
A tracking error signal can be created. Specifically, in the apparatus shown in FIG. 1, a signal having a period twice as long as the above-described header clock is obtained from the PLL 30, and the tracking error amplifier 33 separates the signal output from the bandpass filter 28 to perform comparative amplification. By doing so, an error signal corresponding to the magnitude of the amplitude can be obtained.

The disk storage medium 10 shown in FIG.
In the case of (1), the position of the corresponding header cell is different between the adjacent tracks in the reproduction signal obtained from the header area, so that it is written in the data storage cell 12 of the data storage area 14 in the same manner as in the case of the well-known magnetic disk device. And
In accordance with the track number reproduced by the recording / reproducing circuit 24, the polarity is switched in the tracking control circuit 34 and input to the servo amplifier 35 to drive the actuator 23. If 10 is used, the position of the corresponding header cell in each track becomes the same, so that such control becomes unnecessary. When the example shown in FIG. 2 is used as the disk storage medium 10, a tracking error signal cannot be obtained from the reproduction signal obtained from the header area, but the other operations are the same.

Although the present invention has been described with reference to a magnetic disk drive as an example, the present invention can be applied to a magneto-optical disk drive. Although a DC magnetization state cannot be created, even in a phase-change optical disk, by creating an amorphous state that changes to DC magnetization, the medium can be patterned in the same manner as described above to achieve high density.

[0047]

As described above, according to the present invention, it is possible to accurately store information in each data storage cell using a patterned medium capable of storing information at an extremely high density. . Also, it is extremely easy to prepare ROM information for each medium surface, and a large-capacity magnetic disk device can be configured by stacking a plurality of media.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a disk storage device according to an embodiment of the present invention;

FIG. 2 is a diagram showing an example of a disk storage medium according to an embodiment of the present invention;

FIG. 3 is a diagram showing another example of the embodiment of the disk storage medium of the present invention.

FIG. 4 is a diagram showing still another example of the embodiment of the disk storage medium of the present invention.

FIG. 5 is an explanatory diagram of a relationship between a magnetization state of a cell and a reproduction output in the present invention.

FIG. 6 is an explanatory diagram showing a reproduction output when a phase of a recording timing is changed.

[Description of Signs] 10: disk storage medium, 11: medium substrate, 12: data storage cell, 13, 13a, 13b: header cell, 1
4: data storage area, 15: header area, 21: magnetic head, 22: spindle, 23: actuator, 2
4: recording / reproducing circuit, 25: rotation timing generator, 2
6: timing phase information memory (ROM), 27: switch, 28: bandpass filter (BPF), 29: waveform shaper,
30: phase-locked oscillator (PLL), 31: recording pattern generator, 32: clock phase information memory (ROM), 3
3: tracking error amplifier, 34: tracking control circuit, 35: servo amplifier.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Yoshiaki Kurokawa, Inventor 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Corporation (72) Inventor Yasuhiro Koshimoto 1-3-1 Gotenyama, Musashino City, Tokyo No. F-term in NTT Advanced Technology Corporation (reference) 5D006 BB07 DA03 FA09 5D096 AA01 BB01 CC01 DD05 EE03 GG01 GG04

Claims (10)

[Claims] 1. A disk storage medium in which a plurality of tracks for recording and reproduction are arranged in a ring, each track has an information storage area for recording and reproducing arbitrary information and a predetermined position in a track running direction. The information storage area is divided from adjacent tracks in the track width direction and is also separated from each other in the track running direction. Data storage cells composed of various isolated magnetic material cells are arranged at a predetermined pitch in the track running direction, and the reference magnetic material regions are separated from each other in the track width direction and are also separated from each other in the track running direction. The header cell composed of minute isolated magnetic material cells is arranged in the track running direction with the arrangement pitch n ( A disk storage medium characterized by being arranged at a pitch of (n is an integer of 2 or more) times. 2. The disk storage medium according to claim 1, wherein the ratio of the length of the header cell in the track running direction to the gap between the header cell and the adjacent header cell in the track running direction is 1: 1. 3. The header cell has a length in the track width direction equal to or less than half the track pitch, and each header cell adjacent in the track running direction is alternately arranged on the right or left side of the center in the track width direction. 3. The disk storage medium according to claim 1, wherein: 4. The header cell according to claim 1, wherein said header cell is arranged in a track width direction with a half track pitch offset from a track in said information storage area, and in a track running direction, between adjacent tracks in a track running direction of said header cell. 2. The disk storage medium according to claim 1, wherein the disk storage medium is arranged so as to be shifted by a half of the arrangement pitch. 5. The disk storage medium according to claim 4, wherein the ratio of the length of the header cell in the track running direction to the gap between the header cell and the adjacent header cell in the track running direction is 1: 3. 6. A disk storage device for recording / reproducing information on / from a disk storage medium according to claim 1, wherein at least a header cell is DC-magnetized, wherein a reproduction signal corresponding to an arbitrary track of the disk storage medium is provided. Means for extracting a signal for a period corresponding to the reference magnetic material area from the inside; means for reproducing a first clock corresponding to an arrangement pitch corresponding to a track of the information storage area of the header cell from the signal; Means for generating a second clock corresponding to the arrangement pitch of the data storage cells by multiplying the clock of n by n, and performing recording and reproduction on the data storage cells in the information storage area using the second clock. Characterized disk storage device. 7. A rotation driving means for driving a disk storage medium to rotate and outputting information of a rotation reference position and a rotation angle; and a method of determining a rotation reference position and a position of a reference magnetic region on the disk storage medium. Storage means for storing the relationship; information on the reference position and the rotation angle of the rotation; and the relationship between the stored reference position of the rotation and the position of the reference magnetic region on the disk storage medium, and 7. The disk storage device according to claim 6, further comprising means for generating a signal corresponding to the position of the area. 8. A second storage means for storing a phase difference at which a maximum reproduction output is obtained when recording is performed on a data storage cell with an alternating current while changing a phase of a second clock, 8. The disk storage device according to claim 6, wherein a second clock is created from the first clock and the phase difference. 9. The disk storage device according to claim 6, wherein the disk storage medium according to claim 3 is used for reproducing a reproduction signal in a period corresponding to a reference magnetic region. 2. A disk storage device comprising: means for dividing at a period twice as long as two clocks and obtaining tracking control information by comparing the two. 10. A method for manufacturing a disk storage device according to claim 7, wherein the disk storage medium according to claim 1 is used, wherein the disk storage medium is incorporated in a rotation driving unit of the disk storage device. And DC degaussing the disk storage medium. A period during which a signal of a predetermined level or more is obtained when the DC degaussed disk storage medium is reproduced is defined as a position of a reference magnetic region on the disk storage medium. Storing the relationship between the position and the reference position of rotation obtained from the rotation drive means in the storage means; and repeating the recording and reproduction of the data storage cell with the alternating current while changing the phase of the second clock. Storing the phase difference obtained from the reproduction output in the second storage means. The method of production.