JP2551990B2 - Rewritable disc and disc recording / reproducing device - Google Patents

Description

The present invention relates to a disc in which information can be rewritten and a disc recording / reproducing apparatus for recording / reproducing information on / from the rewritable disc.

[Conventional technology]

2. Description of the Related Art Conventionally, there is known a disk recording / reproducing apparatus which is divided into a plurality of sectors and focuses a laser beam on the surface of a disk that rotates at a constant angular velocity to record external input data such as computer data. . As one example thereof, one using a magneto-optical disk has already been implemented.

Since this magneto-optical disk can have a track density higher than that of a magnetic disk by one digit or more, a large-capacity memory can be formed and a laser beam can be focused on a groove formed in advance on the disk. A major feature is that the optical head can be positioned without contact.

In consideration of control simplicity, the rotation control of the disc is normally performed with a constant angular velocity (CAV: Constant Angular V
elocity). Furthermore, in order to maximize the storage capacity of the disc, MCAV (Modified Constant Angula)
A method called r Velocity) has also been proposed. This MC
In AV, the rotation of the disc is performed at a constant angular velocity as in the CAV described above, and the number of sectors per track of the disc is increased toward the outer peripheral side of the disc.
This is a method of increasing the storage capacity by keeping the recording density at each radial position of the disk substantially constant without lowering the access performance.

When using either the CAV or MCAV method, the above-mentioned disc is formed with tracks such as groups at the stage of making the disc for the purpose of positioning the laser beam, and an absolute address consisting of a concavo-convex pattern. Are formed periodically. This absolute address is
It is usually called an ID and is used as an address for area recognition corresponding to a sector which is one unit of recording and reproduction.

By the way, in addition to the above-mentioned constant angular velocity control, a constant linear velocity (CLV: Constant L
inear velocity) control is known. Specifically, for example, when recording and reproducing a music program or the like on a magneto-optical disc, a so-called compact disc (hereinafter,
It is considered that the magneto-optical disk is rotated at a constant linear velocity like the CD while adopting a data format similar to that of CD). In that case, the absolute address may be periodically formed as a concavo-convex pattern over the entire surface of the disk when the disk is manufactured.

[Problems to be Solved by the Invention]

However, when recording / reproducing computer data or the like while rotating a rewritable disc such as a magneto-optical disc at a constant angular velocity, the absolute address is recorded in advance as a concavo-convex pattern on the disc, so the format is fixed. Then, the so-called hard sector system is adopted, and there is a problem that the user data capacity per sector cannot be changed.

For example, when it is desired to record 256 bytes per sector on a disk having a user data capacity of 512 bytes per sector, half the total capacity of the disk is wasted. On the other hand, if you want to record at 1024 bytes per sector,
You have to treat 2 sectors as 1 sector,
The processing is complicated and the total capacity is 51 per sector.
Since it is the same as the case of 2 bytes, efficient data recording cannot be performed. Therefore, prepare a plurality of types of discs having a sector capacity according to the data to be recorded in advance,
There is the inconvenience of having to use them properly, and it is also difficult to mix data with different sector capacities in the same disk.

On the other hand, for example, when recording and reproducing a music program or the like while rotating the magneto-optical disk at a constant linear velocity, the music program or the like is superimposed as magneto-optical data on the portion where the absolute address is recorded by the above concavo-convex pattern. Will be recorded. At that time, in the portion where the superposition recording is performed, the absolute address information and the magneto-optical data are mixed, so that the reliability of the data is significantly lowered, and an error is likely to occur during reproduction.

By the way, in the CD format, CIRC (Cross Interl
Since it has a powerful error correction function called eave Reed-solomon Code), the information length of the absolute address is short,
And, if the number of error occurrences is small, almost no problem will occur, but as the information length of the absolute address becomes longer,
Moreover, as the number of errors increases, it becomes impossible to correct the errors sufficiently, which hinders the reproduction of a music program or the like. Therefore, it is necessary to set the number of absolute addresses to a small value, for example, about once per one rotation of the disk to suppress the occurrence of errors.

Also, in the case of performing the constant linear velocity control, it is possible to handle computer data such as that performed by a so-called CD-ROM in addition to the music program. However, in the case of the music program, an error should occur. Although the correction can be performed by the correction or the complementary operation, the error cannot be allowed in the computer data, and thus the error must be further suppressed.

As described above, since the absolute address is provided only once per one rotation of the disk, there is a problem that high-speed access operation and accurate CLV control become difficult.

It is an object of the present invention to provide a rewritable disc and a disc recording / reproducing device that can arbitrarily set the sector capacity and can suppress the occurrence of data error due to address assignment.

[Means for solving the problem]

The rewritable disc according to the invention of claim 1 is a rewritable disc in which tracks are previously formed in a spiral shape in a recording area, and the recording area is set within a predetermined radius range from a starting point of the track, and a radius of the disk. A first recording area in which a first absolute address for recognizing a position is formed as a concavo-convex pattern;
And a second recording area which is set in the remaining area of the recording area and in which the third absolute address is recorded as rewritable data based on the first absolute address.

The rewritable disc according to the invention of claim 2 is
In a rewritable disc in which tracks are spirally formed in advance in the recording area, the recording area is set within a predetermined radius range from the starting point of the track, and the first absolute address for recognizing the radial position on the disk is uneven. The first recording area, which is formed as a pattern, and the remaining area of the first recording area are set, the second absolute address is formed at an interval larger than the first absolute address, and the first absolute area is formed. The third absolute address includes a second recording area in which rewritable data is recorded at intervals smaller than the second absolute address based on the absolute address or the second absolute address.

Further, the disk recording / reproducing apparatus according to the invention of claim 3 is the disk recording / reproducing apparatus for performing at least one of recording and reproducing on the rewritable disk according to claim 1 or 2, wherein a light beam is irradiated. Radial position detecting means for obtaining a radial position, and calibration means for calibrating the radial position so as to match the first absolute address or the second absolute address each time the first absolute address or the second absolute address is reproduced. And recording means for recording the third absolute address as rewritable data in the second recording area based on the radial position.

[Action]

According to the rewritable disc of the above-mentioned claim 1, the first radius is formed as the concavo-convex pattern with the predetermined radius range from the starting point of the track of the recording region as the first recording region. When the rewritable disc is mounted, the disc radial position is grasped by recognizing the first absolute address of the first recording region, and based on this, the remaining region of the first recording region of the recording region. The third absolute address is recorded as rewritable data in the second recording area which is

Therefore, for example, when the disk is divided into a plurality of sectors and recording / reproduction is performed while performing rotation control with a constant angular velocity, by selecting the recording cycle of the third absolute address, the sector capacity, that is, per sector The user data capacity can be set to a desired value. Also, the sector capacity can be changed from that at the time of initial recording at the time of re-recording. Further, for example, the sector capacity can be set to 512 bytes in some areas, and the sector capacity can be set to 1024 bytes in the remaining areas, so that the sector capacity can be changed in one disk.

On the other hand, when recording / reproducing is performed while rotating the disc at a constant linear velocity, the third absolute address is recorded as rewritable data in the second recording area other than the first recording area of the recording area. 3 The information such as the absolute address and the music program is not superposed, and the occurrence of an error during reproduction can be suppressed. Also, by recording the third absolute address at sufficiently short intervals, it is possible to speed up access to a desired recording position and ensure CLV control.

Next, according to the rewritable disc of claim 2, not only the first absolute address and the third absolute address but also the second absolute formed in the second recording area in the same uneven pattern as the first absolute address. The addresses are provided with a space larger than the first absolute address.

Therefore, even if a defect such as a track jump occurs during recording of the third absolute address, the third absolute address is calibrated at the time when the second absolute address is detected next time, and the error of the third absolute address is minimized. It is possible to accurately record the third absolute address by suppressing the above. Since the second absolute address is provided at an interval larger than that of the first absolute address, the reproduction error due to the second absolute address when recording / reproducing is performed by the constant linear velocity control is sufficiently small, and the error correction circuit. The reproduction error can be corrected by the operation of.

Further, according to the disk recording / reproducing apparatus of the third aspect, the radial position irradiated by the light beam obtained from the pulse of the spindle motor or the tracking motor is written as rewritable data as the third absolute address. Every time the first or second absolute address is reproduced, its radial position is calibrated.

Therefore, it is not necessary to give an absolute address to the entire area of the rewritable disc in advance, the disc can be used in a desired format, and the superposition recording of the absolute address and the information can be avoided to prevent an error during reproduction. Can be reduced.

Example 1 An example related to claims 1 to 3 in the claims section of the present specification will be described below with reference to FIGS. 1 to 7. .

This embodiment relates to a rewritable disc and a disc recording / reproducing device used for recording / reproducing external input data according to the format standard of a 5.25-inch write-once optical disc based on rotation control with a constant angular velocity.

FIG. 1 shows an example of a magneto-optical disk as a rewritable disk described in claim 1. In this magneto-optical disk 1, a spiral track 21 having an inner peripheral side as a starting point is preliminarily formed in at least an area to be recorded and reproduced. Further, a predetermined radius range of the end portion on the inner peripheral side of the magneto-optical disc 1, specifically, for example, a disc radius of 28 mm to 30 mm
.. are formed as concave and convex patterns at a rate of, for example, 17 per one track in the range.

Next, FIG. 2 shows an example of a magneto-optical disk as a rewritable disk described in claim 2. In this magneto-optical disk 1 ', as in the case of FIG. 1, a spiral track 21 starting from the inner peripheral side is preliminarily formed in at least a region to be recorded / reproduced, and the magneto-optical disk 1 is also formed. A predetermined radius range of the inner peripheral side end of, for example,
.. are formed as concavo-convex patterns at a ratio of, for example, 17 per track in the disk radius range of 28 mm to 30 mm.

Further, the second absolute addresses 23, 23 ... Are formed as a concavo-convex pattern for each predetermined disc radius, for example, for each disc radius of 2 mm, in a region other than the predetermined radius range. In this way, the interval at which the second absolute addresses 23, 23 ... Are provided is set to be considerably larger than the interval at which the first absolute addresses 22. The second absolute address 23.
23 may be provided at every predetermined distance along the track 21, for example, every 100 mm.

The first or second absolute address 22/23 has a format as shown in FIG. That is, since the absolute address is provided at the beginning of the sector, the sector mark (SM) 41 indicating the starting point of the sector is placed at the beginning of the absolute address. Below, a VFO 42 for reproduction synchronization, an address mark (AM) 43 indicating the beginning of an absolute address, and an ID + CRC 44 indicating the value of the absolute address are repeatedly recorded three times in consideration of the occurrence of a reproduction error. .

As shown in FIG. 5, the ID + CRC 44 has a track address 45 indicating a number sequentially incremented from the innermost track of the track for each track, and a sector address 46 indicating a sector number within the track. Information consisting of a CRC 47 as an error detection code for detecting an error at the time of recognizing the track address 45 and the sector address 46 is recorded in advance in a concavo-convex pattern so that it can be reproduced at a predetermined angular velocity. The sector address
46 includes an identification bit indicating the sector capacity (for example, "1" if the sector capacity is 512 bytes, "0", etc. if the sector capacity is 1024 bytes).

Set the track pitch of the magneto-optical disk 1 or 1'to 1.6
Assuming μm, the track address 45 at the first absolute address 22 is “1” for the track address 45 at the inner track edge of the disc radius 28 mm, “625” for the disc radius 29 mm, and “1250” for the disc radius 30 mm. Become.

Also, the track address 45 in the second absolute address 23
Is "2500" for a disk radius of 32 mm, a disk radius of 34 mm
Then, it becomes "3750", and gradually increases toward the outer circumference.

The magneto-optical disk 1 or 1'has a sector format as shown in FIG. That is, the first and second absolute addresses 22 and 23 shown in FIG.
A third absolute address 24 having the same format as the above is recorded, and subsequently, an area 48 such as a CAP is provided for the purpose of recording preparation time. Subsequently, a data field 50 in which additional data such as an error detection / correction code is added to user data of 512 or 1024 bytes, which is a format used in a conventional optical disc or the like, is recorded. A buffer area (BUFF) 51 is provided at the end of each sector to prevent the recording from overlapping the next sector due to fluctuations in the rotation of the disk.

On the other hand, the track format is 31 sectors when the sector capacity is 512 bytes and 17 sectors when the sector capacity is 1024 bytes according to the format standard of the 5.25-inch write-once optical disc. Therefore, as the sector address 46, which is the number corresponding to each sector in the third absolute address 24, when the sector capacity is 512 bytes, “0” to “30” are set to the sector capacity 10
In case of 24 bytes, the value from "0" to "16" is given.

Next, FIG. 6 shows an example of the disk recording / reproducing apparatus of claim 3.

This disc recording / reproducing apparatus is provided with a spindle motor 2 for rotationally driving the magneto-optical disc 1 or 1 '.
An optical head 3 for irradiating the magneto-optical disk 1 or 1'with a light beam to record / reproduce information is arranged on one side of the magneto-optical disk 1 or 1 '. The optical head 3 has a role as a recording unit together with a magnetic coil 16 described later.

Of the information reproduced via the optical head 3 during reproduction,
The uneven signal component from the first or second absolute address 22 and 23 is amplified by the uneven signal reproducing amplifier 4. The amplified concavo-convex signal component is supplied to the address decoder 6 having a role as a calibration means via the selector 5, where the value of the first or second absolute address 22 or 23 or the third absolute address 24 is It is recognized and sent to the controller 7 which controls the entire disc recording / reproducing apparatus. The selector 5 is adapted to select either the uneven signal from the uneven signal reproducing amplifier 4 or the third absolute address 24 from the reproducing amplifier 9 to be described later and supply it to the controller 7.

The rotary encoder 8 as a pulse generating means attached to the spindle motor 2 outputs a predetermined number of pulses per one rotation to the controller 7 according to the rotation of the spindle motor 2. Of the information reproduced by the optical head 3, the magneto-optical signal component is amplified by the reproduction amplifier 9 and sent to the reproduction signal processing circuit 10. The reproduction signal processing circuit 10 processes the data field 50 having the sector format shown in FIG. 3, extracts predetermined data, aligns it, corrects errors as necessary, and outputs it to the outside. It is configured.

The address encoder 12, which functions as a radial position detecting means, is adapted to generate a third absolute address 24 according to the disk radial position, based on a signal from the controller 7. Further, the recording signal processing circuit 14 is configured to convert the externally input data and the third absolute address 24 provided from the address encoder 12 into a recording data string corresponding to the format of FIGS. 3 to 5. Has been done.

The coil driver 15 is a magnetic coil that functions as a recording unit according to the recording signal from the recording signal processing circuit 14.
16 is driven, and an external magnetic field corresponding to a recording signal is applied to the magneto-optical disk 1 or 1'by the magnetic coil 16.

Next, FIG. 7 shows a generation part of the third absolute address 24 in the controller 7.

The rotary encoder 8 outputs, for example, 527 pulses A per rotation as the spindle motor 2 rotates. The pulse A from the rotary encoder 8 is input to the first frequency divider 7a in the controller 7 and is divided into 1/527 by the first frequency divider 7a, so that one rotation is performed for each rotation of the magneto-optical disk 1 or 1 '. The pulse B of the number of times is output by the first frequency divider 7a.

The track counter 7b as a counting means includes first to third absolute addresses 22 to 24 obtained from the address decoder 6.
The track address information C is output by counting the pulse B.

Also, the second frequency divider 7c is the disk 1 from the first frequency divider 7a.
It is reset by the pulse B for each rotation, and the pulse A from the rotary encoder 8 is changed to 1/31 when the sector capacity is 1024 bytes and 1/17 when the sector capacity is 512 bytes according to the sector capacity selection signal D. The frequency is divided and the pulse E is output at a cycle corresponding to each sector.

The sector counter 7d is reset by the pulse B from the first frequency divider 7a, and is configured to count the pulse E from the second frequency divider 7c and output it as sector address information F. The sector address information F and the track address information C are sent to the address encoder 12, and the address encoder 12 generates the third absolute address 24 based on them. A truck counter
The 7b and the sector counter 7d serve as counting means.

The recording operation in the initial state of the magneto-optical disk 1 shown in FIG. 1 will be described below.

As described above, in the magneto-optical disk 1, only the first absolute address 22 is recorded in the predetermined radius range at the inner peripheral edge in the initial state.

When the magneto-optical disk 1 is mounted on the spindle motor 2, the controller 7 controls an optical head moving mechanism (not shown) to move the optical head 3 to the center of a predetermined radius range where the first absolute address 22 is recorded. Disc radius 29mm
And the rotation control of the spindle motor 2 is performed at a predetermined angular velocity. Based on this, the first absolute address 22 is reproduced by the optical head 3, amplified by the concavo-convex signal reproduction amplifier 4, and then sent to the address decoder 6 through the selector 5, and the address decoder 6 reproduces the first absolute address 22. The value is recognized and input to the controller 7.

The track counter 7b is preset by the first absolute address 22, and as a result, the track address information C from the track counter 7b is calibrated to a value according to the radial position of the disc.

With the first absolute address 22 above, the track counter 7b
Is preset, and after the disk radial position is recognized by the controller 7, if necessary, after the access operation or the like is performed to the end position of the first absolute address 22, that is, the disk radius 30 mm position, 3 absolute address
Recording of data including 24 is started.

The recording operation here corresponds to formatting, and the third absolute address 24 is recorded as rewritable magneto-optical data on the magneto-optical disk 1 having no absolute address other than the first absolute address 22 near the outer peripheral edge, This is for preparing for subsequent recording / reproduction in sector units. In that case, only the third absolute address 24 may be recorded, or the recording of the third absolute address 24 and the recording of the external input data may be sequentially switched. Hereinafter, a case where only the third absolute address 24 is recorded will be described.

After the recording signal processing circuit 14 performs predetermined formatting on the third absolute address 24 from the address encoder 12, the magnetic coil 16 is passed through the coil driver 15.
Thus, a magnetic field corresponding to the recorded data is applied on the magneto-optical disk 1. At the same time, the optical head 3 irradiates the magneto-optical disk 1 with a DC light beam having a relatively large output required for recording. Since the coercive force of the portion where the temperature locally rises due to this light beam decreases, the magnetization is reversed by the magnetic field generated by the magnetic coil 16, and the third absolute address 24 is recorded. The above method is generally called magnetic field modulation recording, and overwriting is possible even on an already recorded area.

When recording the third absolute address 24, the optical head 3 sequentially moves from the recording end position of the first absolute address 22 to the outer peripheral side of the disk following the track 21 as the magneto-optical disk 1 rotates. . At that time, the pulse A generated 527 times per rotation by the rotary encoder 8 in response to the rotation of the magneto-optical disk 1 is the first pulse as described above.
A pulse B is generated once per one rotation by the frequency divider 7a and input to the track counter 7b. This pulse B is counted by the track counter 7b, and the track address information C which is counted up every one revolution of the disk is obtained.

At the same time, as described above, the pulse A from the rotary encoder 8 is divided by the second frequency divider 7c according to the sector capacity, and the pulse E corresponding to each sector is output. This pulse E is counted by the sector counter 7d to obtain sector address information F.

The track address information C and the sector address information F are sent to the address encoder 12, and the address encoder 12 generates the third absolute address 24 based on them. The third absolute address 24 is sent to the recording signal processing circuit 14 and sequentially recorded on the magneto-optical disk 1 by the procedure described above. In this way, the third absolute address 24 is recorded over the entire surface of the magneto-optical disk 1.

Next, the procedure for recording the third absolute address 24 on the magneto-optical disk 1'of FIG. 2 will be described.

As described above, the magneto-optical disk 1'has the same first absolute address 22 in the vicinity of the inner peripheral edge as the magneto-optical disk 1 of FIG.
Is recorded, and as described above, the first absolute address
The second absolute address 23 is recorded in a region other than the recorded predetermined radius range of 22, for example, as a concavo-convex pattern for every 2 mm of the disk radius.

In this case, when recording the third absolute address 24, the second
By reproducing the absolute address 23, the track address information C is sequentially calibrated.

That is, during the recording of the third absolute address 24, the relatively large output DC light beam is applied to the magneto-optical disk 1'by the above-described recording method, so that the second absolute address is generated by this light beam. 23 can be played. At this time, the reproduction signal output level of the optical head 3 has a large amplitude as much as the amount of light increases as compared with the normal reproduction, but by reducing the gain of the concave / convex signal reproduction amplifier 4, it is the same as that at the time of reproduction. Can be read.

As described above, when only the third absolute address 24 is recorded instead of recording the third absolute address 24 by sequentially switching the external input data, the second absolute address 23
When the reproduction timing of No. 2 and the recording timing of the third absolute address 24 do not overlap, the reproduction of the second absolute address 23 can be performed as in the normal reproduction.

The second absolute address 23 is reproduced for each 2 mm radius of the magneto-optical disk 1'and input to the track counter 7b. With this second absolute address 23, the track counter
Calibration of the contents of 7b is performed. This calibration is for eliminating an error that occurs in the track address information C when the light beam of the optical head 3 causes an abnormality such as a track jump due to a defect or dust of the disk. In this way, by calibrating the contents of the track counter 7b with the second absolute address 23 reproduced at a predetermined interval, even if an error occurs in the track address information C, the error is stored in the disc. It is prevented that even the outer peripheral portion is held, and the recording error of the third absolute address 24 is minimized.

In the above example, the frequency division ratio in the second frequency divider 7c is selected on the basis of the sector capacity selection signal D. However, the sector capacity thus selected is the sector capacity as described above. It is added in the address 46 as a sector capacity identification bit.

Instead of the above method, the sector capacity is selected by an external command, specifically, by a selection switch provided in the disk recording / reproducing device or by a command from a host device such as a host computer. Alternatively, it may be performed by recognition by 7.

When the sector capacity can be set from the outside as described above, not only can the sector capacity be fixed over the entire surface of the disk, but also the sector capacity can be changed within one disk. For example, disk radius 30-40
In the range of mm, sector capacity is 1024 bytes, disk radius is 40
At ~ 60mm, the sector capacity can be set to 512 bytes.

When a new disk is used while changing the sector capacity according to the radial position as described above, the third absolute address 24 is provided on the entire surface of the disk prior to the recording of information, and the period corresponding to the sector capacity at each radial position is used. You can record with.

Further, when it is desired to change the sector capacity of a part of the disk where the third absolute address 24 has already been recorded, a new access is performed after referring to the recorded third absolute address 24. It is sufficient to record the third absolute address 24 according to the format. In the reformatting here, the previously recorded third absolute address 24 is input to the track counter 7b, so that the track address information C is calibrated by the recorded third absolute address 24.

Next, recording of data on the magneto-optical disk 1 or 1'on which the third absolute address 24 is recorded will be described.

First, the third absolute address 24 is reproduced in order to access the sector at the recording start position on the magneto-optical disk 1 or 1 '. When reproducing the third absolute address 24 as a magneto-optical signal, as is known, the polarization component corresponding to the magnetization direction is detected by the optical head 3, amplified by the reproducing amplifier 9, and then the address decoder via the selector 5. The third absolute address 24 is decoded by 6 and input to the controller 7.

As a result, the desired sector, which is the recording start position, is accessed. Thereafter, desired data is input from the outside, converted into the sector format shown in FIG. 3 by the recording signal processing circuit 14, and then recorded on the magneto-optical disk 1 or 1'by the magnetic coil 16 driven by the coil driver 15. To be done. The recording operation here is the third absolute address 24
Is the same as the conventional one except that is given as a magneto-optical signal.

Next, when reproducing the recorded data, the polarization component of the magneto-optical signal reproduced from the rotating magneto-optical disk 1 or 1'is detected by the optical head 3 as in the case of reproducing the third absolute address 24 described above. After being amplified by the reproduction amplifier 9, the reproduction signal processing circuit 10 performs a predetermined conversion and outputs as external output data.

[Second Embodiment] Next, a second embodiment corresponding to claims 1 to 3 in the claims section will be described. The second embodiment also performs the recording / reproducing operation by the rotation control with a constant angular velocity.
The number of sectors per one rotation of the magneto-optical disk 1 or 1'is increased toward the outer circumference of the disk so that the recording density becomes substantially constant over the entire surface of the disk.

That is, in the present embodiment, the magneto-optical disk 1 or 1'shown in FIG. 1 or 2 is used as in the first embodiment, but one rotation of the magneto-optical disk 1 or 1 ', that is, 1 The number of sectors per track is 512 and the sector capacity is 512.
In the case of bytes, for example, the innermost circumference of the disc is 31 sectors, and the outermost circumference is 62 sectors.

On the other hand, when the sector capacity is 1024 bytes, the number of sectors per track is increased toward the outer circumference side, for example, 17 sectors at the innermost disk circumference and 34 sectors at the outermost disk circumference. Therefore, the third absolute address 24
The sector address 46 in the middle contains the contents corresponding to the number of sectors, that is, (0 to 3 when the sector capacity is 512 bytes.
0, 0-61), but if the sector capacity is 1024 bytes, (0
-16, 0-33) are shown for each track.

As shown in FIG. 8, the disk recording / reproducing apparatus of this embodiment has basically the same configuration as that of the first embodiment shown in FIG. However, the controller 7'supplies the recording signal processing circuit 14 with the recording clock I for designating the recording cycle of information according to the disk radial position.

FIG. 9 shows the third absolute address in the controller 7 '.
The generation part of 24 is shown in detail.

Similarly to the first embodiment, the first frequency divider 7'a divides the pulse A, which is output from the rotary encoder 8 serving as the pulse generating means 527 times per rotation of the disk, into 1/527 to divide the disk 1 into 1/527. The pulse B is output once per rotation. Further, the track counter 7'b as the counting means is provided with the first to the first supplied from the address decoder 6.
Preset by the third absolute addresses 22 to 24, the pulse B from the first frequency divider 7'a is counted and the track address information C is output.

Further, the conversion table 7'c uses the track address information C as the second division ratio G corresponding to the disk radial position so that the data recording density becomes substantially constant at all radial positions of the disk. It outputs to the frequency divider 7'd. The second frequency divider 7'd is reset by the pulse B for each rotation of the disk, and divides the pulse H of the predetermined frequency from the oscillator 7'e according to the frequency division ratio G from the conversion table 7'c. To obtain the recording clock I corresponding to the disk radial position.

The third frequency divider 7'f is reset by the pulse B for each rotation of the disk, counts the recording clock I from the second frequency divider 7'd, and sets the sector capacity to either 512 bytes or 1024 bytes. A sector start position signal K in the disk circumferential direction is output in accordance with a sector capacity selection signal J indicating whether or not to perform the operation. The sector counter 7'g is configured to count the sector start position signal K from the third frequency divider 7'f and output sector address information L. The sector address information L and the track address information C are sent to the address encoder 12, and the address encoder 12 generates the third absolute address 24 based on these.

Recording of the third absolute address 24 on the magneto-optical disk 1 shown in FIG. 1 will be described below. As described in the first embodiment, the recording of the third absolute address 24 may be sequentially switched from the recording of the external input data, but here, the case of recording only the third absolute address 24 will be considered.

When the magneto-optical disk 1 is mounted on the spindle motor 2, the optical head 3 is first moved to the radial position where the first absolute address 22 is recorded, and the first absolute address 22 is read, as in the first embodiment. Is read out and the radial position of the magneto-optical disk 1 is grasped by the controller 7 '.

Next is the recording end position of the first absolute address 22,
For example, the optical head 3 is moved to a position where the disk radius is 30 mm, and recording of the third absolute address 24 is started. At this time, the optical head 3 records the third absolute address 24 while sequentially moving to the outer peripheral side of the disk along the track 21,
As described above, the pulse A output from the rotary encoder 8 527 times per disk rotation is converted into the pulse B once per disk rotation by the first frequency divider 7'a in the controller 7 ', and the track counter 7 ′
The pulse B is counted by b and the track address information C
Is output.

At the same time, the conversion table 7'c gives the frequency division ratio G corresponding to the disk radial position indicated by the track address information C to the second frequency divider 7'd, and the second frequency divider 7'd.
The d outputs the recording clock I corresponding to the disk radial position by dividing the pulse H from the oscillator 7'e by the dividing ratio G. This recording clock I is a recording signal processing circuit.
The recording cycle of the third absolute address 24 is adjusted so that the recording density is substantially constant at all radial positions of the disk.

The recording clock I is sent to the third frequency divider 7'f, and the sector capacity selection signal J causes the sector capacity to be, for example, 1024.
In the case of bytes, the recording clock I is divided by 1 / α. That is, if it is the innermost circumference of the disc, the disc 1
If the sector start position signal K of 17 times per rotation is the outermost circumference of the disk, the frequency division is performed so that the sector start position signal K of 34 times is output per rotation of the disk.
The above frequency division value α may be a value corresponding to the number of recording clocks corresponding to the entire length of one sector shown in FIG.

The sector counter 7'g is reset by a pulse B once per rotation of the disk, and by counting the sector start position signal K from the third frequency divider 7'f, the sector corresponding to the position in the circumferential direction of the disk. The address information L is obtained. The sector address information L and the track address information C are sent to the address encoder 12, and the address encoder 12 generates the third absolute address 24 based on these. The sector capacity designated by the sector capacity selection signal J is added to the third absolute address 24.

The third absolute address 24 is sent from the address encoder 12 to the recording signal processing circuit 14, where it is converted into a predetermined format and then recorded on the magneto-optical disk 1 by the magnetic coil 16.

When the third absolute address 24 is recorded on the magneto-optical disk 1'shown in FIG. 2, as in the first embodiment, the first absolute address 22 is recorded in an area other than the recorded predetermined radius range.
For example, the second absolute address 23 recorded every 2 mm of the disk radius is sequentially reproduced during the recording of the third absolute address 24, and the track address information C is calibrated based on the second absolute address 23. As a result, even if an error occurs in the track address information C, it is promptly corrected and the recording error of the third absolute address 24 is controlled to the minimum.

Although the above description has been made assuming that the sector capacity is 1024 bytes, when the sector capacity is 512 bytes, the frequency division value in the third frequency divider 7'f is set to β,
Sector start position signal K output from the third frequency divider 7'f
However, if the innermost circumference of the disc is output, 31 times are output per rotation of the disk, and if the outermost circumference of the disk is output, 62 times are output per rotation of the disk.

Further, in the above example, the sector capacity is designated by the sector capacity selection signal J, but as in the first embodiment, the sector capacity is designated by operating the selection switch, or by a host computer or the like. It may be designated by a command from the apparatus, and in this case, the sector capacity can be changed depending on the radial position within one magneto-optical disk 1 or 1 '.

The procedure of recording and reproducing the external input data to the magneto-optical disk 1 or 1'on which the third absolute address 24 is recorded as described above is the same as that of the first embodiment.

In the above embodiment, the sector start position signal K is generated in the third frequency divider 7'f by counting the recording clock I from the second frequency divider 7'd.
The sector start position signal K is generated by the rotary encoder 8
It may be performed by counting the pulse A from the.

Third Embodiment Next, a third embodiment will be described. This third embodiment relates to a rewritable disc and a disc recording / reproducing apparatus for recording / reproducing while controlling rotation at a constant linear velocity in relation to claims 1 to 3 of the claims. It is disclosed.

FIG. 10 shows a magneto-optical disk 30 as a rewritable disk corresponding to claim 1. The magneto-optical disk 30 is formed with a track 31 whose starting point is the inner peripheral side, as in the above embodiments. In addition, track 31
A predetermined radius range near the inner peripheral edge of the disk, for example, the disk radius 23
A plurality of first absolute addresses 32 are recorded as a concavo-convex pattern in a range of -25 mm per track 31.

Further, FIG. 11 shows a magneto-optical disk 30 'as a rewritable disk corresponding to the second aspect of the present invention. This magneto-optical disk 30' has a track 31 which is similar to that of FIG. The first absolute address within the specified radius range near the inner edge
32.32 are provided, and the second absolute addresses 33, 33 ... Are spaced apart from the first absolute address 32.32 ... in an area other than the predetermined radius range, for example, 1 for every 1 mm of disk radius. It is recorded as a concavo-convex pattern at a rate of individual pieces. The interval between the adjacent second absolute addresses 33, 33 is a predetermined interval along the track 31, for example, 100 mm.
Alternatively, it may be a predetermined time, for example, an interval of being reproduced once every 60 seconds.

The first and second absolute addresses 32 and 33 are, as shown in FIG. 13, a preamble 52 for reproduction synchronization and an address mark 53 indicating the beginning of the first or second absolute address 32 and 33. , An address number 54 indicating an address that is sequentially incremented from the innermost circumference of the magneto-optical disk 30, 30 ', for example, for each circumference of the track 31, and an error detection code 55 for detecting an error when the address number 54 is detected. Is equipped with.

The track pitch of the magneto-optical disk 30 or 30 'is 1.6μ
If m, the address number 54 of the first absolute address 32
Is "1" at the starting point of the disc radius of 23 mm, "625" at the disc radius of 24 mm, and "1250" at the disc radius of 25 mm. Also, the address number 54 of the second absolute address 33 is
Following the address number 54 of the first absolute address 32, "1875" for a disk radius of 26 mm and "2" for a disk radius of 27 mm.
It becomes 500 ", and thereafter gradually increases toward the outer circumference of the disk.

As shown in FIG. 12, the recording format of data on the magneto-optical disk 30 or 30 'is the same as that of the conventional read-only CD. That is, the information of one frame includes a subcode 57 indicating the program number and time information of the music program for each data field 58 in which 8 bytes of parity for error detection is added to the data of the music program of 24 bytes. , Frame sync signal indicating the beginning of the frame
56 is added, and such information is sequentially recorded. However, in the present embodiment, the subcode 57 described above is used.
Includes at least the third absolute address 34.

FIG. 14 shows an example of a disk recording / reproducing apparatus for recording and reproducing on the magneto-optical disk 30 or 30 '.

Since this disc recording / reproducing apparatus has substantially the same structure as the disc recording / reproducing apparatus of the first embodiment shown in FIG. 6, the same members are designated by the same reference numerals, and detailed description thereof will be omitted. However, in the present embodiment, the selector 5 of the first embodiment is omitted, the output signal of the uneven signal reproducing amplifier 4 is directly sent to the address decoder 6, and the magneto-optical disk 30 or 30 'is rotated at a constant linear velocity. For driving
A CLV control circuit 35 is newly provided.

Further, as external input data, analog music information input from Sin is input to the recording signal processing circuit 14 via the A / D converter 13, and external output data from the reproduction signal processing circuit 10 is also D / A converter. S through 11
It is output as out.

The controller 7 ″ is the controller 7 of the first embodiment.
The internal configuration is slightly different from. FIG. 15 shows in detail the generation portion of the disk radial position information in the controller 7 ″.

The counter 7 ″ a as the counting means is preset by the first or second absolute address 32 · 33 obtained from the address decoder 6 having the role as the calibration means, and for example, one rotation of the spindle motor 2 from the rotary encoder 8 is performed. , The number M of pulses output 100 times is counted to output the track number information N. The track number information N is sent to the address encoder 12, and based on the track number information N, the address encoder 12 outputs 3 Absolute address 34 is generated.

The conversion table 7 ″ b is adapted to generate the disk radial position information O corresponding to the track number information N.
Since this conversion table 7 ″ b is for obtaining a predetermined output for a predetermined input, it may be constituted by a memory such as a ROM (Read Only Memory), or the track number information N
It is also possible to configure by a computing unit that calculates the disk radial position information O corresponding to.

Further, the selector 7 ″ c has a reference radius position set in advance, specifically, a reference radius indicating a disk radius of 24 mm, which is a radius position corresponding to the center of a predetermined radius range in which the first absolute address 32 is recorded. Any one of the radial position signal P, the disk radial position information O from the conversion table 7 ″ b, and the third absolute address 34 supplied from the reproduction signal processing circuit 10 is selected and output as the disk radial position information Q. It is like this.

The operation of the disc recording / reproducing apparatus in this embodiment will be described below.

The CLV control circuit 35 responds to the disk radial position information Q given from the controller 7 ″, and the spindle motor 2 required to achieve a predetermined linear velocity at that radial position.
Of the spindle motor 2 is compared with the actual rotation speed obtained from the pulse from the rotary encoder 8 so that the actual rotation speed of the spindle motor 2 matches the required rotation speed. The rotation speed of the motor 2 is controlled.

For example, if the predetermined linear velocity is 1.2 m / s and the disk radius position information Q is 24.0 mm, the required rotation speed of the spindle motor 2 is 1.2 / (2 × π × (24 × 10 ⁻³ )) ≈7.96 [Rps], which requires 7.96 revolutions per second. On the other hand, since the rotary encoder 8 outputs a pulse, for example, 100 times for one rotation of the magneto-optical disk 30 or 30 ',
The pulse frequency reference value at the above required rotation speed is 7.96.
× 100 = 796 [Hz]. Therefore, the linear velocity constant control can be realized by controlling the rotation speed of the spindle motor 2 so that the pulse frequency from the rotary encoder 8 becomes the pulse frequency reference value.

In the actual constant linear velocity control, the disc radial position information Q is recorded as the optical head 3 moves in the disc radial direction.
Is sequentially supplied from the controller 7 ″ to the CLV control circuit 35, so that the pulse frequency reference value at each disk radial position is obtained and rotation control is performed.

Next, recording of the third absolute address 34 in the initial state of the magneto-optical disk 30 will be described.

When the magneto-optical disk 30 is mounted on the spindle motor 2, the controller 7 ″ controls an optical head moving mechanism (not shown) to move the optical head 3 to the center of a predetermined radius range where the first absolute address 32 is recorded. 24.0 in radial position
While moving to a position substantially equivalent to mm, 24.0 mm is given to the CLV control circuit 35 as disk radial position information Q corresponding to the above radial position. As the disc radial position information Q here, the reference radial position signal P preset in the selector 7 ″ c is selected and output, and the CLV control circuit 35 performs the rotation control at the desired linear velocity as described above. Done.

Along with this, the first absolute address 32 is output from the optical head 3 as a reproduction signal and amplified by the concave / convex signal reproduction amplifier 4, and then the first absolute address 32 is recognized by the address decoder 6 and the controller 7 ″ It is input to the counter 7 ″ a. In the control up to this point, since the disk radial position information Q does not always match the actual radial position, it may be difficult to obtain an accurate linear velocity, but this hinders the reproduction recognition of the first absolute address 32. There is no problem in linear velocity, so there is no problem.

The counter 7 "a is preset by the above-mentioned first absolute address 32. Therefore, the preset first absolute address 32 is directly output from the counter 7" a as the track number information N. When this track number information N is input to the conversion table 7 "b, the conversion table 7" b outputs the disk radial position information O corresponding to it. In this embodiment, since the track pitch is 1.6 μm, the disc radial position information O can be obtained by multiplying the track number information N by 1.6 μm.

In the selector 7 "c, after the first absolute address 32 is recognized, the disk radial position information O from the conversion table 7" b is selected and output as the disk radial position information Q.

After recognizing the first absolute address 32, the controller 7 ″ performs an access operation to the recording end position of the first absolute address 32 as necessary, and then performs the third absolute operation to the area after the end position of the first absolute address 32. Recording of the address 34 is started.In this case, first, only the third absolute address 34 may be recorded over the entire surface of the magneto-optical disk 30, or information such as a music program including the third absolute address 34 may be recorded. In the following, the case of recording a music program including the third absolute address 34. The music program may have a meaningful content, or is equivalent to a music program having no special meaning. It may be data.

An analog input signal Sin such as a music program input from the outside is digitized by the A / D converter 13 and sent to the recording signal processing circuit 14. Here, the music program is converted into a predetermined format with the third absolute address 34 from the address encoder 12 incorporated in the subcode 57, and then the magneto-optical disc is driven by the magnetic coil 16 driven by the coil driver 15. Recorded on 30.

At the time of the above recording, the optical head 3 has the first absolute address.
After the position where the recording of 32 is completed, the recording medium is sequentially moved to the outer peripheral side along the track 31, and at that time, the CLV control circuit 35 performs the constant linear velocity control based on the disk radial position information Q from the controller 7 ″.

In the above example, the counter 7 ″ is based on the first absolute address 32.
Although a is preset to calibrate the track number information N, this is equivalent to calibrating the disk radial position information Q. Further, as another method, the CLV control circuit 35 may directly calibrate the required rotation speed.

When recording the third absolute address 34 on the magneto-optical disk 30 'shown in FIG. 11, first, as in the above, first,
The counter 7 ″ by reproducing the first absolute address 32
After the track number information N of a is calibrated, recording of the third absolute address 34 is started. In this case, while recording the third absolute address 34, for example, the track number information N is sequentially recorded by the second absolute address 33 reproduced every 1 mm of the disk radius.
Is calibrated. As a result, the third absolute address 34 can be generated more accurately.

According to the CD format, the third absolute address 34 is recorded at a frequency of at least 9 times or more per one rotation of the disc, so that the access operation in the subsequent recording / reproduction can be performed at high speed.

Next, a magneto-optical disk on which a music program or the like is recorded
The reproduction of 30 or 30 'will be described.

First, in the magneto-optical signal reproduced from the rotating magneto-optical disk 30 or 30 ', the polarization component is detected by the optical head 3 and amplified by the reproducing amplifier 9 as described in the above embodiment, and then reproduced. The signal processing circuit 10 restores the original digital audio signal and outputs it as an analog output signal Sout via the D / A converter 11.

On the other hand, regarding the constant linear velocity control during reproduction, the third absolute address 34 sequentially reproduced by the reproduction signal processing circuit 10 is used as the disc radial position information Q via the selector 7 ″ c.
By being given to the CLV control circuit 35, the same linear velocity constant control as described above is executed.

The reproduction signal quality here is such that, in the magneto-optical disk 30, since there is no absolute address due to the concavo-convex pattern in the recording range of the music program, the reproduction error of the magneto-optical signal is extremely small.

On the other hand, in the magneto-optical disk 30 ', the second absolute address 33 exists at every predetermined radius, but the second absolute address 33
Since the interval at which the first absolute address 32 is provided is considerably larger than the interval at which the first absolute address 32 is provided, the frequency of errors caused by the second absolute address 33 can be suppressed to a sufficiently small level. Therefore, even if an error occurs, the CIRC
It is possible to correct to the extent that no problem occurs by the error correction function such as.

Next, the reproducing / recording operation of the music program etc. after recording the third absolute address 34 will be described.

The re-recording operation is basically the same as the recording operation of the third absolute address 34 described above, and after the desired recording start position is accessed with reference to the third absolute address 34, the desired length is changed to the desired length. Can be recorded by overwriting by magnetic field modulation.

Further, regarding the constant linear velocity control during the re-recording operation, after the disk radial position is calibrated by the third absolute address 34 of the position immediately before the start of the re-recording, during the re-recording, a pulse from the rotary encoder 8 is used as described above. Similarly, the track number information N is sequentially generated, and the track number information N is given to the CLV control circuit 35 as the disk radial position information Q. And during re-recording,
The third absolute address 34 generated by the address encoder 12 based on the track number information N is recorded in the re-recorded music program. When re-recording on the magneto-optical disk 30 ', the track number information N is sequentially calibrated by the second absolute address 33 reproduced every predetermined radius.

In the above example, the first absolute address 32 has the format shown in FIG. 13, but other formats may be adopted. Also, the first absolute address 32 is a CD
As a method of conforming to the absolute address of, the first absolute address 32 can be recorded in a predetermined radius range of the disc according to the format of the TOC area on the CD.

Although the rotary encoder 8 is used to detect the rotation speed of the spindle motor 2 in each of the above-described embodiments, various pulse generating means other than the rotary encoder 8 can be used.

〔The invention's effect〕

As described above, in the rewritable disc according to the first aspect of the present invention, the first absolute address is formed with the predetermined radius range from the track starting point as the first recording area, and the third absolute area is formed in the remaining second recording area. The absolute address is recorded as rewritable data.

Therefore, when the disc is mounted on the disc recording / reproducing apparatus, the first absolute address is recognized to grasp the disc radial position, and the third absolute address is recorded based on this.

Therefore, for example, when the disk is divided into a plurality of sectors and recording / reproducing is performed by rotation control with a constant angular velocity,
By selecting the recording cycle of the absolute address, the sector capacity, that is, the user data capacity per sector can be set to a desired value. Also, the sector capacity can be changed from that at the time of initial recording at the time of re-recording. Further, for example, the sector capacity can be set to 512 bytes in some areas, and the sector capacity can be set to 1024 bytes in the remaining areas, so that the sector capacity can be changed in one disk.

On the other hand, when recording / reproducing is performed while rotating the disc at a constant linear velocity, the third absolute address is recorded as rewritable data together with information such as a music program in the second recording area. Therefore, it is possible to suppress the occurrence of an error during reproduction. Further, by recording the third absolute address at sufficiently short intervals, it is possible to speed up access to a desired recording position and ensure CLV control.

Further, in the rewritable disc according to the second aspect of the invention, as described above, even in the second recording area,
The second absolute addresses are formed in a concavo-convex pattern at intervals larger than the absolute addresses.

Therefore, when recording the third absolute address as rewritable data in the second recording area, the third absolute address can be calibrated based on the second absolute address. Therefore, even if a trouble such as a track jump occurs during the recording of the third absolute address, the error of the third absolute address can be kept within the minimum range and the accurate absolute address can be recorded. .

Further, as described above, the disk recording / reproducing apparatus according to the third aspect of the present invention writes the radial position irradiated by the light beam detected by the radial position detecting means as the third absolute address. This radial position is calibrated each time the absolute address or the second absolute address is reproduced.

Therefore, recording / reproducing can be performed on the rewritable disc according to claim 1 or 2.

[Brief description of drawings]

1 to 7 show one embodiment of the present invention, and FIG. 1 is a schematic plan view showing a rewritable disc,
FIG. 2 is a schematic plan view showing another rewritable disc,
FIG. 3 is an explanatory diagram showing a sector format, FIG. 4 is an explanatory diagram showing a format of the first or second absolute address,
FIG. 5 is an explanatory diagram showing the format of ID + CRC, FIG. 6 is a block diagram showing a disk recording / reproducing apparatus, FIG. 7 is a block diagram showing an internal configuration of a controller, and FIGS. 8 and 9 show other embodiments. FIG. 8 is a block diagram showing an example of a disk recording / reproducing apparatus, FIG. 9 is a block diagram showing an internal configuration of a controller, and FIGS.
FIG. 15 shows still another embodiment, FIG. 10 is a schematic plan view showing a rewritable disc, FIG. 11 is a schematic plan view showing another rewritable disc, and FIG. Explanatory diagram showing format of information, FIG. 13 is explanatory diagram showing format of first or second absolute address, FIG.
FIG. 15 is a block diagram showing a disk recording / reproducing apparatus, fifteenth.
The figure is a block diagram showing the internal configuration of the controller. 1, 1 ', 30, 30' are magneto-optical disks (rewritable disks), 3 are optical heads (recording means), 6 are address decoders (calibration means), 7b, 7'b are track counters (counting means), 7 ″ a is a counter (counting means), 12 is an address encoder (radial position detecting means), 16 is a magnetic coil (recording means), 22 and 32 are first absolute addresses, 23 and 33 are second absolute addresses, and 24. 34 is the third absolute address.

Claims (3)

(57) [Claims] 1. A rewritable disc in which tracks are spirally formed in advance in a recording area, and the recording area is set within a predetermined radius range from a starting point of the track, and is a first disc for recognizing a radial position on the disc. One absolute address is set in the first recording area formed as a concavo-convex pattern and the remaining area of the first recording area.
A rewritable disc comprising: a second recording area in which a third absolute address is recorded as rewritable data based on the absolute address. 2. A rewritable disc in which tracks are spirally formed in advance in a recording area, wherein the recording area is set within a predetermined radius range from a starting point of the track, and is a first area for recognizing a radial position on the disk. One absolute address is set in the first recording area formed as a concavo-convex pattern and the remaining area of the first recording area.
The second absolute address is formed at an interval larger than the absolute address, and the third absolute address is recorded as rewritable data at an interval smaller than the second absolute address based on the first absolute address or the second absolute address. A rewritable disc including a second recording area. 3. A disk position recording / reproducing apparatus for recording and / or reproducing on / from the rewritable disk according to claim 1 or 2, further comprising a radial position detecting means for determining a radial position irradiated with a light beam. Calibration means for calibrating the radial position to match the first absolute address or the second absolute address each time the first absolute address or the second absolute address is reproduced; A disc recording / reproducing apparatus comprising: a recording unit for recording the third absolute address as rewritable data in the second recording area.