JP2002343041A - Recording and reproducing method for disk-like recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity and to increase a data recording capacity by making it possible to perform exact track following even if signals for servo tracking are not recorded to the entire track. SOLUTION: A disk drive 1, which divides the tracks of the disk-like recording medium 10 to one or plural servo tracks S and other data tracks D and performs the recording/reproducing of the disk-like recording medium 10 by writing the signals for servo tracking to the entire circumference of the servo tracks S, captures trace information by tracking the servo tracks S, moves a head 3 to the target data tracks D by measurement of a length measuring instrument 5, performs track following by trace movement of the head 3 in accordance with the trace information and efficiently uses the recording capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing method for a disk-shaped recording medium such as a magnetic recording medium and an optical recording medium, and more particularly, to a reduction in a servo tracking signal for accurately following a head. Things.

[0002]

2. Description of the Related Art Conventionally, in a disk-shaped recording medium such as a magnetic recording medium or an optical recording medium, linear recording density and track density have been increased in order to improve recording capacity. In particular, regarding the improvement of track density,
For example, in the case of a flexible disk having a track density of 500 TPI or more, even if the track is deformed from a circular shape to an elliptical shape due to the eccentricity of the track due to the deviation of the rotation center due to the chucking accuracy when the disk is set in the drive, thermal expansion, etc. In order to accurately trace the head on the track, track following has been performed by adopting a servo tracking method by writing a servo tracking signal. For this purpose, it is necessary for a manufacturer to write servo tracking signals in advance on all tracks on a disk-shaped recording medium, which leads to complication of a manufacturing process and an increase in production cost.

[0003]

For example, in a magnetic disk medium, a servo field in which a servo tracking signal is written includes not only a servo pattern (burst signal) as a servo tracking signal for track positioning but also a track pattern. Address (gray code)
Are recorded. When this servo tracking signal is recorded on all tracks, the number of tracks is large, so that the writing time is long, the production efficiency is reduced and the cost is disadvantageous, and the data area is reduced and the recording capacity is reduced. Cannot be used. In other words, there is a problem that the servo field increases in accordance with the improvement of the recording capacity, and an efficient increase in the recording capacity cannot be obtained.

Similarly, in an optical disk medium,
It is necessary to form a land / groove groove for servo tracking in all tracks, and it is not possible to use the recording capacity efficiently, and it is necessary to particularly consider differences in the reflectance of the land / groove groove, etc. It is an obstacle to the improvement of the recording capacity due to the development.

In view of the above, the present invention has been made in view of the above point, and enables accurate track following without writing a servo tracking signal to all tracks, thereby improving the productivity of a disk-shaped recording medium. It is an object of the present invention to provide a recording and reproducing method for a disk-shaped recording medium which can improve the data recording capacity and the data recording capacity.

[0006]

According to the recording / reproducing method of a disk-shaped recording medium of the present invention, a track of the disk-shaped recording medium is divided into one or a plurality of servo tracks and another data track, and the servo tracks of the servo track are recorded. A disk drive that records a servo tracking signal all around the track and records / reproduces data on / from the disk-shaped recording medium tracks the servo track, captures trace information, and moves the head to a target data track using a length measuring device. , And the head is traced based on the trace information to perform track following.

One or more servo tracks are provided at one of the outer peripheral side, the inner peripheral side, and the intermediate portion of the disk-shaped recording medium, or two or more servo tracks are provided. In this servo track, a servo tracking signal is recorded on the entire circumference at a predetermined interval, and in the data track, this servo tracking signal is not recorded. When a plurality of servo tracks are prepared, eccentricity and disk deformation due to chucking of the disk-shaped recording medium can be estimated over the entire recording area by tracking each servo track. Further, it is possible to improve the tracing accuracy by performing track following based on the trace information of the servo track near the target data track.

In a disk drive, when a head for tracking a servo track and a head for moving to a data track and recording / reproducing data are also used, fetched trace information is stored. Track following is performed based on the stored trace information. Alternatively, when a servo head for tracking a servo track and a read / write head for recording / reproducing data to / from a data track are provided separately, the read / write is performed in conjunction with the servo track tracking by the servo head. It is possible to perform track following by moving the head for tracing, and it may not be necessary to store trace information.

The length measuring device is a laser length measuring device, a glass scale length measuring device, or the like, measures a head position from a reference position such as a servo track, and performs feedback control of the head position based on the measurement to obtain a target position. The seek is moved to the data track, and the data track is trace-moved based on the trace information.

The disk drive includes a spindle motor for holding a disk-shaped recording medium and rotating at a predetermined rotational speed, a servo head for tracking a servo tracking signal of a servo track of the disk-shaped recording medium and obtaining trace information, A read / write head that is also used as a servo head or separate from the head, seek moving means for moving the head in a radial direction, a length measuring device for measuring the head position, and measurement and trace information based on the measurement and trace information of the length measuring device. Control means for controlling the operation of the seek moving means.

[0011]

According to the present invention as described above, a servo track on which a servo tracking signal is recorded is tracked to acquire trace information, and a head is moved to a target data track by measuring with a length measuring device. Track tracking is performed based on trace information, so that accurate track following can be performed without recording servo tracking signals on all tracks, and highly reliable data recording. / Playback.

[0012] Further, by recording a servo tracking signal on the entire circumference of one or a plurality of servo tracks on a disk-shaped recording medium and not recording a servo tracking signal on a data track, it is possible to manufacture a disk-shaped recording medium. In the process, writing of servo tracking signals and formation of land / groove grooves are not required on the entire surface, so that productivity can be improved and cost can be reduced, and a substantial increase in recording capacity can be achieved by efficient use of recording capacity. On the other hand, in the case of an optical disk medium, it is not necessary to consider the difference in the reflectivity of the land / groove groove and the like, so that the reliability can be improved and the density can be increased.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is a schematic diagram showing a disk drive according to one embodiment of the present invention, and FIG. 2 is a control block diagram thereof. Although this embodiment describes a magnetic disk medium, the same applies to an optical disk medium.

The disk-shaped recording medium used in the present invention is:
The concentric tracks are divided into one or more servo tracks and other data tracks, and servo tracking signals are recorded on the entire circumference of the servo tracks. In this servo tracking signal, among the servo signals, particularly a burst signal for position control is recorded at predetermined intervals all around the circumference (about 1000 to 10000 per rotation). Further, gray information such as angular position information is recorded on the servo track. No servo signal is recorded on the data track.

One servo track is provided on the outer circumference side, inner circumference side, intermediate portion, or the like of the disk, or both the outer circumference side and the inner circumference side,
Furthermore, it is preferable to install three or more including an intermediate part. For example, in the disk-shaped recording medium 10 of FIG. 2, servo tracks S are formed on the outer peripheral side and the inner peripheral side, and data tracks D are formed at a predetermined track pitch in other effective recording areas.

In the production factory, a servo track writer or the like is used to write a servo tracking signal to the servo track S on the disk-shaped recording medium 10 by using a servo track writer or the like.
Writing of gray information is performed. When a track is formed on this disk-shaped recording medium, the track is formed concentrically with the set center (center of rotation), and even when eccentricity, deformation, or the like occurs, each track has a substantially similar shape. The trace movement of the head when tracking each track has substantially the same characteristics in each track.

As shown in FIG. 1, a disk-shaped recording medium 1
A disk drive 1 for recording / reproducing 0 records a disk-shaped recording medium 10 and rotates the spindle motor 2 at a predetermined speed, and a servo-tracking signal of a servo track S of the disk-shaped recording medium 10 to track the trace information. A head 3 for recording and reproducing data on and from the data track D, a seek moving means 4 for moving the head 3 in a radial direction, and a length measuring device 5 (laser measuring device) for measuring a head position. And a control means 6 shown in FIG. 2 for controlling the operation of the seek moving means 4 based on the measurement and trace information of the length measuring device 5.

The disk drive 1 tracks the servo track S and captures the trace information (eccentricity information, angular position information, etc.), and moves the head 3 to the target data track D by measurement of the length measuring device 5. The head 3 is trace-moved based on the trace information to perform track following, and data is recorded / reproduced to / from the data track D based on the angular position information of the trace information.

The spindle motor 2 has a spindle shaft 2
1. The central portion of the disk-shaped recording medium 10 (flexible disk) set in the chuck portion 22 at the front end is chucked and rotated at a high speed to a predetermined speed. The angular position information is managed in synchronization with the rotation of the spindle motor 2.

The head 3 includes upper and lower head portions 3 arranged so as to sandwich the disk-shaped recording medium 10.
, 31 are vertically opposed to each other.
Has a slider on which a known head element is formed, and a gimbal for supporting the slider.
Are fixed to the tips of the upper and lower suspensions 32, 32, respectively, and the rear ends of the suspensions 32, 32 are attached to the head base 33. In addition, both head parts 3
1, 31 are opened and closed by a known load mechanism (not shown).

The seek moving means 4 includes a VCM 41 (voice coil motor), and moves the head base 33, that is, the head 3, in seek and trace movements. The head base 33 is supported by a guide 42 so as to be able to reciprocate, and a VCM
The stop position is accurately controlled by the position control using the length measuring device 5 while the moving operation is performed along the guide 42 by driving the 41. In addition, other known mechanisms can be adopted as the seek moving means 4.

In the length measuring device 5 (laser length measuring device), a reflector 51 is provided on the head base 33 to detect the position of the head 3 from the position of the head base 33, and a reflector 51 is provided from a laser transducer 52 via a half mirror 53. The reflector 51 is irradiated with laser light, the reflected light is incident on the receiver 54 via the half mirror 53, the position is detected by the length measurement, and sent to the control means 6 described later. Load, unload, seek operation, trace operation, and the like of the head 3 are performed under control according to the length measurement. In addition, a known precision length measuring device such as a glass scale length measuring device can be used as the length measuring device 5 instead of the laser length measuring device.

As shown in FIG. 2, the control means 6 includes a preamplifier 61 for receiving a head output and a servo control unit 62 for performing reference servo control based on reading of a servo tracking signal from the preamplifier 61 and storing trace information. VCM receiving the length measurement output from the length measuring device 5 (receiver 54) and the signal from the servo control unit 62
And a position control unit 63 that outputs a drive signal to the driver 64. The preamplifier 61 exchanges data with a data processing unit (not shown) that performs signal processing of data to be recorded / reproduced on the data track D by the head 3.

When the control means 6 is tracking the servo track S, the servo control section 62 sends a signal corresponding to the eccentricity to the position control section 63 based on the servo tracking signal read by the head 3. , A drive signal is output to the VCM driver 64 to move the head 3 to the center of the track, and reference servo tracking is performed to trace the movement. The movement of the head 3 at that time indicates eccentricity, deformation, etc. of the track. The servo control unit 62 stores this trace information in a memory (RAM).

When the seek movement to the target data track D is performed, the position control unit 63 sends the VCM driver 6
The VCM 41 is driven by a command to the head 4, and the head 3 is moved to seek until the head 3 reaches the target length measurement value. In the data track D, track following is controlled by moving the head 3 in a trace based on the trace information.

That is, the position control unit 63 performs feedback control of the VCM 41 based on the measurement of the position of the head 3 by the length measuring device 5 to move the seek to the target data track D, and the data track D has eccentricity and deformation. Since the servo track S is similar in shape to the servo track S, the target data track D is accurately track-followed by performing a trace movement equivalent to the trace movement of the head 3 during tracking of the servo track S based on the stored trace information. To control.

When there are a plurality of servo tracks S, the eccentricity and disk deformation due to chucking of the disk-shaped recording medium 10 are estimated over the entire recording area by tracking each servo track S, and stored as trace information. It may be.

Next, the operation of the disk drive 1 will be described. First, the disk-shaped recording medium 1 loaded in the drive
0 is held on the spindle shaft 21 of the spindle motor 2 and driven to rotate at a predetermined rotation speed. The VCM 41 is driven to move the head 3 to the position of the servo track S. Then, the servo track S is
, The servo tracking is performed so that the head 3 accurately traces the servo track S based on the signal, and the trace information corresponding to the trace movement is stored.

Next, the head 3 is moved to seek the target data track D, and feedback control of the VCM 41 is performed so that the measured value of the length measuring device 5 corresponding to the track position is obtained. And data track D
The data is recorded / reproduced while controlling the drive of the VCM 41 based on the stored trace information so as to trace the head 3 and accurately follow the target data track D. .

FIG. 3 is a schematic diagram of a disk drive according to another embodiment. In this example, a head for tracking the servo track S and a head for recording / reproducing data on the data track D are separate.

The disk drive 11 of this embodiment includes a servo head 7 for tracking a servo track S.
Read / write head 8 for recording / reproducing data to / from data track D; seek moving means 4 for independently moving servo head 7 and read / write head 8 in the radial direction; servo head 7 and the position of the read / write head 8 respectively.
(Laser length measuring device), and the spindle motor is the same as described above. The servo head 7 always reads the servo tracking signal by tracking the outer side servo track S of the disk-shaped recording medium 10.

The servo head 7 and the read / write head 8 have a head portion 7 formed in the same manner as described above.
Reference numerals 1 and 81 are fixed to the front ends of the respective suspensions 72 and 82, and the rear ends of the suspensions 72 and 82 are attached to the respective head bases 73 and 83.

Although the seek moving means 4 is not specifically shown, each of the servo head 7 and the read / write head 8 is provided with a VCM (not shown), and each head base 73,
83, ie, the servo head 7 and the read / write head 8 are separately moved by seek and trace.

In the length measuring device 9 (laser measuring device), reflectors 91 and 92 are installed on head bases 73 and 83 of the servo head 7 and the read / write head 8, respectively. The light is split by a beam splitter 94 for both heads, and the split laser beams are applied to both reflectors 91 and 92 via a half mirror 95, respectively.
The reflected lights are respectively incident on the receiver 96 via the half mirror 95, and the position of the heads 7 and 8 is detected by the length measurement.

A control means (not shown) for controlling the operation of the servo head 7 and the read / write head 8 by the seek moving means 4 based on the length measurement of the length measuring device 9 includes a servo track S by the servo head 7. The track following operation is performed by moving the read / write head 8 in a trace in association with the trace information based on the tracking. As described above, a preamplifier receiving the head output from the servo head 7 and a servo tracking from the preamplifier are performed. A servo control unit for performing reference servo control based on reading of a signal for use, a servo head 7 and a read / write head 8 which receive a length measurement output from the length measuring device 9 (receiver 96) and receive a signal from the servo control unit. And a position controller for outputting a drive signal to each of the VCM drivers.

In the control means of this embodiment, the trace control of the read / write head 8 can be performed in cooperation with the servo head 7 without storing the trace information in the servo control unit. The read trace information may be stored and the trace control of the read / write head 8 may be performed. In addition, since the angular position can be known at any time by reading the servo head 7, synchronization management with the rotation of the spindle motor becomes unnecessary.

The present invention is also applicable to an optical disk medium, in which servo tracking information for trace control is written only in a servo track, and in a data track, a difference in reflectance between lands / groove grooves is not considered. Help me.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a disk drive according to one embodiment of the present invention.

FIG. 2 is a block diagram showing control means of the disk drive of FIG. 1;

FIG. 3 is a schematic diagram of a disk drive according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 11 Disk drive 2 Spindle motor 3 Head 4 Seek moving means 5, 9 Length measuring device 6 Control means 7 Servo head 8 Read / write head 10 Disk-shaped recording medium S Servo track D Data track

Claims (1)

[Claims] 1. A track of a disk-shaped recording medium is divided into one or a plurality of servo tracks and another data track, and a servo tracking signal is recorded all around the servo track. A disk drive that performs recording / reproduction tracks the servo track, captures trace information, moves a head to a target data track by measuring with a length measuring device, and traces the head based on the trace information. A recording / reproducing method for a disk-shaped recording medium, comprising performing track following.