JPH0554457A - Magneto-optical disk device - Google Patents

Abstract

PURPOSE:To attain the high speed of recording, reproducing and access operation in a magneto-optical disk device by which the recording, reproducing and access operation on a disk shaped recording carrier are performed. CONSTITUTION:Within a movable range of an objective lens 2, a moving means, in which routes crossing all tracks of the magneto-optical disk 1 are made plural like 20a, 20b and a selecting means for the routes by which, when a series of operations for erasing, recording and reproducing or the access operation is performed, these processes are completed in the shortest time by access distance, sector positional information, etc., are provided. In this constitution, before a prescribed sector at a prescribed track in the route 20a is erased and the magneto-optical disk 1 rotates once to return to the position, an optical head is moved to the route 20b, and a recording operation, which is the next operation, is performed in shorter time than the time required for one rotation of the magneto-optical disk 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk capable of high speed recording, reproducing and accessing operations on a disk-shaped record carrier.

[0002]

2. Description of the Related Art As disk devices, there are magnetic recording devices such as hard disk devices and floppy disk devices, and optical disk devices such as CDs, write-once optical disk devices and magneto-optical disk devices. All of these correspond to the increase in capacity and the speed of data access accompanying the recent increase in recording density.

Among them, the optical disk device narrows the light to the diffraction limit and can record a large amount of data for recording and reproducing the data by the minute spots. Especially, a rewritable magneto-optical disk device will be used for a computer in the near future. It is said that it will replace the magnetic recording device as an external recording device, and has already been put to practical use.

Since a magneto-optical disk (hereinafter referred to as a disk) has a very small track pitch of 1 to 2 μm, a minute optical spot is made to follow a target track of a rotating disk with high accuracy during recording and reproduction. Must be,
Further, in order to record and reproduce data on a predetermined track in the disc, it is necessary to move the light spot to the target track.

In order to realize these, in general, the emitted light of a semiconductor laser light source is made incident on an objective lens integrated with an actuator through an optical prism or the like, and is narrowed down to a minute light spot on the disk, and this actuator is used. A method is used in which the light spot is moved to a target track of the disc by moving in the radial direction of the disc.

In order to speed up access and processing speed, it is necessary to reduce the weight of the objective lens actuator which is a movable part. To reduce the weight of the actuator, the semiconductor laser light source, the optical prism, the photodetector, etc. were used as fixed parts, and only the objective lens and the reflection mirror were integrated with the actuator consisting of an electromagnetic coil. A method (hereinafter referred to as a separate type optical head) has been proposed.

A conventional magneto-optical disk device of a separation type optical head will be described below. As shown in FIG. 9, 6 is a spindle motor for rotating the disc 1, and 2 is an objective lens for focusing on the recording film of the disc 1. Reference numeral 3 is a swing arm portion for holding the objective lens 2 and for positioning the disc 1 in the radial direction.
It rotates around a rotation shaft 4 arranged outside the disk 1. An optical head fixing portion 5 that accommodates a semiconductor laser, various prisms, optical elements and sensors for detecting tracking error and focus error, which are not mounted on the swing arm portion 3, is fixed to the device base 26.
The parallelogram prism 25 guides the laser light from the optical head fixing portion 5 to the objective lens 2. The objective lens 2 is composed of four lenses, and is driven by a focus actuator 23 that is movable in a focus direction by a focus support spring 27 and has a coil wound around it. Reference numeral 24 in the figure is a galvanometer mirror.

The operation of the optical disk magnetic device constructed as described above will be described below.

The light emitted from the semiconductor laser in the optical head fixing portion 5 is guided to the rotary shaft 4 by the galvano mirror 24,
It reaches the objective lens 2 through the parallelogram prism 25,
The objective lens 2 forms a minute spot of about 1 to 2 μm on the disc 1. The light reflected here is again the objective lens 2 and the parallelogram prism 2 as modulated light including a recording signal and a position control signal component of the objective lens 2.
5, Returning to the optical head fixing unit 5 via the rotary shaft 4 and the galvano mirror 24. A signal is detected by an optical sensor in the optical head fixing portion 5, and a recording signal or the like is extracted. Here, the movement of the disc 1 to the target track is coarsely controlled in the radial direction of the disc 1 by the swing arm unit 3 having the rotating shaft 4 as an axis. However, since it is not possible to control a minute position of several μm or less with this alone, the galvano mirror 2
A minute position control is carried out by 4.

For recording, a magnetic field corresponding to recording and erasing is given by a bias magnetic field provided on the side opposite to the objective lens 2 with respect to the disk 1, and only a portion of the disk 1 irradiated with laser light has a predetermined direction. Is magnetized to.

In the magneto-optical disk device, the direction of magnetization is determined in the disk 1 by a bias magnetic field provided outside.
The light spot determines the region to be magnetized. Therefore, when erasing pre-recorded data and recording new data, temporarily erase the recorded data by setting the bias magnetic field upward or downward, then reverse the direction of the bias magnetic field. Records the light spot by modulating the light spot according to the recording data and magnetizing only a predetermined area in the opposite direction to that in the erasing. Further, in order to check whether or not the data was correctly recorded, the laser power is lowered this time, and the verify operation of the recorded data is performed by the reproducing operation.

In order to record new data on the disk 1 in this manner, three operations of erasing, recording and reproducing verify are required, and three rotations of the disk 1 are required to perform these operations.

Therefore, even if the moving time to the target track (hereinafter referred to as seek time) is minimized by downsizing the optical head, three rotations are required to wait until the writing is actually completed after reaching the target track. Time is added (access time is defined as the sum of seek time and rotation waiting time). For example, in a magneto-optical disk device that rotates the disk 1 at 1800 rpm, 3 times per rotation.
It takes 3 ms, and at least two revolutions, that is, 66 ms or more is required to complete the series of operations. At present, a magneto-optical disk drive, which requires only 35 ms as a seek time to move 6000 tracks, has been put into practical use, and this rotation waiting time is not at an acceptable level.

Next, access will be described. When the access is started and the light spot is moved to the target track, the sector position when the target track is reached cannot be generally controlled. Obviously, it is possible to change the rotation speed of the disk 1, but it is very difficult to control the rotation speed of the rotation motor 6 of the disk 1 having a large inertial force in such a short time.

Therefore, for example, the light spot at the point b (n-3 sector of the i-th track) on the disk 1 shown in FIG. 10A is at the point a (n + 4 sector of the j-th track) on the disk 1. When you go to read the data,
As shown in (b), in the case where the sector position when the light spot reaches the j-th track is the (n + 4) th sector because the disk 1 is rotating during the access, then the (n + 3) th sector is located. It has to wait nearly one revolution before the sector reaches the position c of the light spot.

[0016]

As described above, in the conventional structure, the processing time becomes slow due to the rotation waiting time, and the seek time of the magneto-optical disk device is shortened. The existence has a problem that it becomes a large factor that limits the throughput.

The present invention solves the above-mentioned conventional problems, and provides an optical disk magnetic device which shortens the disk rotation waiting time, performs recording / reproduction and access at high speed, and speeds up data processing. The purpose is to

[0018]

In order to achieve this object, an optical disk magnetic apparatus of the present invention comprises a converting means for erasing, recording and reproducing signals on a disk and a track arranged on the disk. The moving means is provided with a moving means for moving, and the converting means can move the first path which crosses all the tracks on the disk and the second path whose position is different from the first path. Means for selecting whether to perform each of the operations in the first path or the second path is provided.

Further, it is provided with means for detecting and recognizing a sector which is divided and arranged in each track and which is a basic unit of the recording area, and when the converting means is moved, the values of the current position sector and the moving destination sector of the converting means. According to the above, there is provided means for selecting either the first route or the second route as the destination.

[0020]

With this configuration, when data is recorded, first, a predetermined sector of a predetermined track is erased in the first path. Then, before the disk makes one rotation and returns to that position, the optical head is moved to the second path, and the next recording operation is performed in a time earlier than the time required for the disk to make one rotation. Become. Further, in some cases, after this operation, the optical head is returned to the first path again, and before the disk makes one revolution, the next operation, that is, the reproduction verify operation is performed.

[0021]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1, 2 and 7 showing an embodiment of the present invention, the same parts as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 1, in the swing arm portion 6 and the rotation shaft 4, the optical head fixing portion 5 to the objective lens 2 are provided.
A reflection mirror or the like provided to guide the laser beam is provided. An actuator unit 10 which is a drive unit of the swing arm unit 6 is a focus actuator wound with a coil for driving the objective lens 2 in the focus direction, and a tracking actuator which rotates the swing arm unit 6 along a path indicated by a broken line 20. It consists of

The light emitted from the semiconductor laser in the optical head fixing portion 5 enters the actuator portion 10 from the light emitting portion 7 through the beam shaping prism or the like formed in the optical head fixing portion 5, and the reflection mirror and the swing arm. The objective lens 2 is reached via the section 6. The incident light on the objective lens 2 forms a minute spot of about 1 to 2 μm on the disk 1, and the light reflected here includes a recording signal and a control signal component of the actuator unit 10 for controlling the position of the objective lens. The included modulated light returns to the optical head fixing portion 5 again via the objective lens 2, swing arm portion 6, rotating shaft 4 and actuator portion 20. A prism, an optical sensor, and the like are configured in the optical head fixing unit 5, and the optical sensor detects a signal and extracts a recording signal and the like. The disk 1 rotates in the direction indicated by arrow A.

Here, the movement of the disc 1 to the target track is controlled in the radial direction of the disc 1 by the swing arm portion 6 having the rotary shaft 4 as an axis.

As shown in FIG. 2, the light spot from the objective lens 2 has a movement path indicated by a broken line 20 with respect to the disk 1. In other words, the disk 1 is traversed twice by the paths 20a and 20b that cross all tracks in the entire movable range. Although the recording area 8 does not perform recording in the disk 1, it has the same optical characteristics as the recording area 8 and has at least an area 9 in which focus servo of the objective lens 2 is possible.

The swing arm portion 3 of this embodiment is constructed to be lightweight, and can be used for access to move a number of tracks as well as for minute movements when following the tracks. The actuator can be used. Of course, as another configuration method, the coarse movement actuator and the fine movement actuator may be separately configured.

The operation of the optical head during recording will be described with reference to FIG. In this figure, the arrangement of actuators and the like is omitted, and only the positions of the light spots are shown by black circles.
As shown in FIG. 3A, the optical head instructed to perform the recording operation moves from the current track 21 to the recording target track 22 along the path 20a. In order to erase the previous data, the light spot reaching the track 22 is perpendicular to the surface of the disk 1 by a bias magnetic field (not shown) provided on the side opposite to the optical head via the disk 1. Upwards,
Alternatively, the erase operation is performed by applying a downward magnetic field. After completing the erase operation of a predetermined sector (d area in this case),
In the future, the bias magnetic field will be changed to the direction opposite to that when erasing to perform the recording operation.
After passing through the route 20a as shown in FIG.
After leaving 2, the path 20b is entered, and the previously erased sector area moves to that position before reaching the area e according to the rotation operation of the disk. Then, when the previous erasing sector reaches that position, the laser beam is immediately modulated and controlled to perform the recording operation. As a result, the erasing and recording operations are completed while the disk rotates about 1/3.

Next, the reproduction verify operation will be described. As shown in FIG. 3C, the optical head again passes through the path 20.
The process returns from b to the path 20a, waits until the sector area f that has been erased and recorded first in the areas d and e arrives, and immediately after that, the reproduction verify operation is performed.

Here, an example of the actual required time will be calculated. For example, if the rotation of the disk 1 is 1800 rpm, it takes 33 ms to make one rotation, and it takes about 10 ms to move from the area d to the area e shown in FIG. If the swing arm unit 3 can be moved during this period, the erasing and recording operations can be performed in the shortest time as described above. When the reproduction verify operation is entered, the entire operation is completed within 33 ms for one rotation of the disc. For example, if this is done by the conventional method, double the number of rotations is required to complete the entire operation in 33 ms.

If the moving time of the optical head does not accompany the rotation of the disk 1 (for example, when a plurality of sectors are continuously recorded (the optical head is on the path 20a in FIG. 2 and the last sector has been erased) When the first erased sector has already reached the path 20b when))), this operation is not performed and the path remains in the path 20a as before, and waits until the sector comes again. I should do it. However, even in this case, if the erasing operation is started on the path 20b, the optical head may have sufficient time to move to the optical path 20a because the disk 1 is rotating in the direction indicated by the arrow A. This is possible, and the time can be shortened by the difference in this position.

The sequence flow of the movement control when the swing arm unit 13 shifts from erasure to recording is processed as shown in FIG. That is, when a recording instruction is given,
Make a decision according to the current route. For example, route 20
If it is in a, the number of erased sectors is counted, and if the number of sectors is n or less, an instruction to move to another path is given. If the number is n or more, it is determined that the movement time is insufficient and the vehicle stays at that position. On the contrary, when the vehicle is on the route 20b, the sector determination number is m (m>
Similar determination operation is performed as n). This makes it possible to complete the series of operations without error and at a higher speed.

Next, the operation at the time of access will be described with reference to FIGS. As shown in FIG. 5, the position of the current light spot is set to the a1 area (s1 sector of the t1 track), and the position of the data to be reproduced is set to the a2 area (t2).
S2 sector of track). The light spot starts moving from the t1 track to the t2 track in response to the access command, but since the disk 1 is rotating in the direction shown by the arrow A during this operation, when the light spot reaches the t2 track, a2 is set. The position of the area is at the position indicated by the point c, and it is necessary to wait until the area a2 reaches the position of the light spot.

Therefore, it is determined whether the access should be stopped on the route 20a or the route 20b according to the current position and the sector number of the destination, and the movement control is performed. That is, the t2 track position (b1) of the route 20a
Travel time up to the t2 track position (b
Since the moving time up to 2) can be roughly estimated in advance, the position of the target sector of the target track within this time is calculated from the disk rotation speed, and the moving destination path that can move to the reproduction or recording operation quickly is determined. To

That is, as shown in FIG. 6A, when the current position of the light spot at the start of access is the a1 area (s1 sector of the t1 track) and the movement destination is the a2 area (s2 sector of the t2 track), When point X on track t2 is reached via 20a, point a2 is shown in FIG. 6 (b).
At the position shown by, you have to wait nearly one revolution before playing or recording. Therefore, if this is calculated in advance and the light spot is moved to the point Y of the path 20b, the positional relationship as shown in FIG. 6C is obtained, and the reproduction or recording operation is immediately performed in the area a2. You can enter. By such selection control, the rotation waiting time can be shortened and a faster access operation can be performed.

(Second Embodiment) A second embodiment of the present invention will be described below.

As shown in FIGS. 7 and 8, 11 is a spindle motor chucking position for rotating the disk 1, 12 is an objective lens, 18 is a carriage for holding the objective lens 12, and the focus direction of the disk 1 is shown. A focus actuator, a galvanometer mirror, and the like are provided for positioning to. The carriage 18 is integrated with the linear motor 16, is guided and supported by the shaft 17 and the guide 13, and is configured to be movable in the radial direction of the disk 1. The optical head fixing portion 15 not mounted on the movable portion is provided outside the recording area of the disc 1. Reference numeral 14 is a hole for guiding the laser light from the optical head fixing portion 15 to the carriage 18.

The operation of the magneto-optical disk device configured as described above will be described below.

The light emitted from the semiconductor laser in the optical head fixing portion 15 enters the carriage 18 via the optical prisms in the carriage 18 and is guided to the objective lens 12. The movement of the disc 1 to the target track is controlled by the linear motor 16 in the radial direction of the disc 1. However, when the fine position control cannot be performed by this alone, the fine position control in the radial direction is performed by the combination of the fine movement control galvanometer mirror and the linear motor provided in the carriage 18. The moving path 28 of the objective lens actuator is configured to be able to move approximately the diameter of the disk 1, and the track can be traversed by two paths as in the previous example. Since the center of the disk 1 has a mounting hole for the spindle motor, a light reflection film cannot be formed.
Is slightly deviated from the diameter of the disk 1 to form a movement path of a light spot in a region where a reflective film can be formed. Therefore, the objective lens 12 can perform the correct focus position control within the disc moving range. According to this configuration, two tracks 28a and 28b can be obtained for the track crossing paths with a single optical head as in the first embodiment, and the same data recording control or access control as in the first embodiment is realized. It is possible to obtain the same effect.

[0040]

As is apparent from the above description of the embodiments of the present invention, the present invention comprises the converting means and the moving means for traversing the tracks of the disk, and the moving means is the first means for the converting means to traverse all the tracks on the disk. The route and the second route having a different position from each other can be moved, and the configuration is provided with means for selecting whether each of the single operations of the converting means is performed in the first route or the second route. It is possible to realize an excellent optical disk magnetic device that shortens the rotation waiting time of the disk, performs recording / reproduction and access at high speed, and increases the data processing speed.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a main part of an optical disk magnetic device according to a first embodiment of the present invention.

FIG. 2 is a schematic plan view showing a movement path of a light spot of the optical disk magnetic device.

FIG. 3 is a plan view of an essential part showing the operation at the time of recording in the optical disk magnetic device.

FIG. 4 is a sequence flow of path selection at the time of recording in the optical disk magnetic device.

FIG. 5 is an explanatory diagram of problems in accessing the same optical disk magnetic device.

FIG. 6 is a plan view of a principal part showing an operation at the time of accessing the same optical disk magnetic device.

FIG. 7 is a schematic perspective view of a main part of an optical disk magnetic device according to a second embodiment of the present invention.

FIG. 8 is a plan view of a principal part showing a movement path of a light spot of the optical disk magnetic device.

FIG. 9 is a perspective view of a main part of a conventional optical disk magnetic device.

FIG. 10 is an explanatory diagram of problems during operation of the optical disk magnetic device.

[Explanation of symbols]

 1 Magneto-optical disk 2 Objective lens 3 Swing arm part 4 Rotation axis 5 Optical head fixing part 20 Path

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shingo Sakata 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A conversion means for erasing, recording, and reproducing signals on a magneto-optical disk having spiral or concentric tracks, and a moving means for moving the track across the conversion means. The moving means can move a first path where the converting means crosses all tracks on the magneto-optical disk and a second path whose position is different from the first path,
A magneto-optical disk device comprising means for selecting whether to perform each of the single operations of the converting means such as recording, reproducing and erasing in the first path or the second path. 2. A means for detecting and recognizing a sector, which is dividedly arranged in each track and forms a basic unit of a recording area,
A means for selecting either the first path or the second path as a destination according to the values of the current position sector and destination sector of the converting means when the converting means is moved. The magneto-optical disk device according to item 1.