JPH03130929A - Recording medium - Google Patents

Abstract

PURPOSE:To increase usable data regions by providing an access code in a servo region and dividely putting track address information into the access code. CONSTITUTION:The reproduction signal from an optical disk is supplied via an input terminal 20 to a synchronizing pattern detecting circuit 21 and an access code reproducing circuit 22. The reproduction timing signal from the clock pit of the servo region is simultaneously supplied from a timing controller 27. The information on the reference position is put into the reference pattern and access code recorded in the servo region at the top of the track so as to obtain the sector information in the circuit 21. The sector information is divided and is put into the plural access codes if the one access code has no capacity to allow the recording of the sector information, such as sector address. The management on the recording/reproducing of the data is executed by using the address information, such as track address in such a manner.

Description

[Detailed description of the invention] A. Industrial application field The present invention relates to a sample servo type recording medium.

B0 Summary of the Invention The present invention provides a sample servo type recording medium in which a segment consisting of a servo area where a servo signal is recorded and a data area where data is recorded is arranged in the track direction which is the recording/reproducing direction. An access code is provided in the servo area, and by dividing track address information into the access code, the track address that was previously required is eliminated.Furthermore, by entering reference position information on the track in the servo area, sector marks can be set. ,
This eliminates sector addresses and increases the data area available to the user.

C9 Conventional technology Recording media, for example, optical disks such as write-once optical disks and magneto-optical disks, are rotated by a spindle motor or the like at constant linear velocity (CLV) or constant angular velocity (CAV), and a spiral or Data (information) is recorded/reproduced on concentric recording tracks. In addition, in these optical disks, the so-called self-clock method and external clock method are known as clock synchronization methods during data recording/reproduction. ) is arranged in the track direction, which is the recording/h direction, and a sample servo method (or discrete block method) is known in which clock synchronization and tracking servo control are performed using servo signals in the servo region. ing.

Here, a sample servo type optical disc will be explained using FIG. 7. In FIG. 7, one track of the optical disc 1 is composed of a sector 2 which is a recording unit of n pieces of data (information), and one sector is composed of m segments. One segment is composed of a servo area 3 and a data area 4 (a header area 5 in which addresses and the like are recorded in the first segment of the sector or in the first few segments). The servo area 3 includes a clock pit 16 for synchronizing clocks, a pair of so-called wobble pits 17a for obtaining a tracking error signal,
17b and information corresponding to a plurality of pits on the lower side of the track address, for example, an access code 18 using a delay code, is provided in advance at the time of disk formation in order to improve access performance in the radial direction. Here, a pattern composed of the clock bit I6 and the wobble pits 17aS 17b is referred to as a synchronization pattern 15.

FIG. 8 shows the specific recording form of the synchronization pattern 15 and access code 18 recorded and formed in the servo area 3, with the radial direction being the vertical direction. As shown in FIG. 8, the lower 4 bits of the track address The information is recorded as an access code consisting of two pits using a gray code. That is, access codes of the same pattern are recorded at 16 track cycles, and the access codes on adjacent tracks satisfy the characteristics of the Gray code, differing only in one pit position.

In addition, following the servo area 3 of the first segment which is the first segment of the sector (the header area 5 contains a sector mark 6 indicating the beginning of the sector and the address area 7 contains a track address (track number), a sector address (sector number))
The address information (10 codes) such as "0" is recorded in advance at the time of disk formation. For example, in the case of a magneto-optical disk, data (information) is recorded/reproduced in the data area 4 following the servo area 3 of the second to m-th segments using the magneto-optic effect.

Here, synchronization control operations (rotation synchronization IIJ control, tracking servo control, etc.) in a recording/reproducing apparatus that records and reproduces data on an optical disc having the above recording format will be described. FIG. 9 is a block circuit diagram showing the main parts of the recording/reproducing apparatus. In FIG. 9, a reproduction signal reproduced from an optical disk rotationally driven at a constant angular velocity (CAV) by a spindle motor is transmitted via an input terminal 60 to a synchronization pattern detection circuit 61, a sector mark detection circuit 62, and an address reproduction circuit 63. , an access code reproducing circuit 64, and a servo information generating circuit 65, respectively. Further, a reproduction timing signal reproduced from the clock bit 16 of the servo MMJ 3 is supplied to these circuits from the timing controller 72.

In the synchronization pattern detection circuit 61, the synchronization pattern 15 of the servo area 3 is detected, and a byte counter 66 for managing time within the segment is initialized. This byte counter 66 counts the number of bytes in the l segment by counting a predetermined clock signal from the timing controller 72, and when it counts up a predetermined number (counts up), a carry signal is sent to the segment counter 67.

The sector mark detection circuit 62 detects the sector mark 6 in the bend area 5, and initializes a segment counter 67 that manages time in units of segments within the sector. This segment counter 67 is a byte counter 66.
The number of segments in l sector is counted by counting the carry signals from
count up), then the carry signal is sent to sector counter 6.
Sent to 8th.

In the address reproduction circuit 63, the sector address of the header area 5 is reproduced, and a sector counter 68, which manages time in units of sectors within a track, is initialized in synchronization with the reproduction of sector invalidity. This sector counter 68 counts the number of sectors (II large n) in one track by counting the carry signal from the segment counter 67.

The byte counter 66, segment counter 67, and sector counter 68 are operated by a predetermined clock signal from the timing controller 72, and each count information from these counters is transmitted to the timing controller 72.
Rotation synchronization such as segment synchronization, sector synchronization, and track synchronization is performed.

After the rotation is synchronized, the servo information generation circuit 65 generates servo information such as tracking servo control based on the reproduction signals of the wobble pits 17a and 1'7b in the servo area 3, and this servo information is used by the timing controller. 72 is stored in the servo information register 71 using a predetermined clock signal. Then, tracking servo control is performed based on this servo information, and in the address reproducing circuit 63, the reproduced track address is
The track address register 69 is stored in response to a predetermined clock signal from the timing controller 72.

In the access code reproducing circuit 64, an access code (a plurality of lower bits of the track address) is reproduced from the access code 18 of the servo area 3, and is stored in the track access register 70 according to a predetermined clock signal from the timing controller 72. .

The track address stored in the track address register 69, the access code stored in the track access register 70, and the servo information register 7
The servo information stored in 1 is taken out from the terminal,
Data (information) recording/reproduction management is performed using these address information and the like.

D1 Problems to be Solved by the Invention By the way, when a sector mark, a track address (track number), and a sector address (sector number) are provided in the header area 5 of each sector as described above, the area for recording data becomes smaller. The recording capacity N (data area usable by the user) of the entire optical disc decreases. Also, records/
A sector mark detection circuit, a track address reproducing circuit, and a circuit for reproducing sector addresses are required in the reproducing apparatus, which increases the cost of the recording/reproducing apparatus.

The present invention has been made in view of the above circumstances, and it is possible to write addresses such as track addresses on a recording medium, for example, a sample servo type optical disk, using an access code and a synchronization pattern that are prerecorded in the servo area. The purpose of the present invention is to provide a recording medium with a large recording capacity from which information can be obtained, and to provide a recording/reproducing device by removing the sector mark detection circuit, track address reproducing circuit, and sector address reproducing circuit from the recording/reproducing device. The purpose of the present invention is to provide a recording medium that can reduce costs.

89 Means for Solving Problems The recording medium according to the present invention is a sample in which a segment separated from a servo area where a servo signal is recorded and a data area where data is recorded is arranged in the track direction which is the recording/reproducing direction. In a servo type recording medium, an access code is provided in the servo area, and track address information is divided into the access code to solve the above problem.

Furthermore, the above problem is solved by including reference position information on the track in the servo area.

18 Effects According to the recording medium according to the present invention, when data (information) is recorded/reproduced on a recording medium, for example, an optical disc, track address information can be obtained using the access code. Also, based on the reference position information of the servo area mentioned above,
Sector address information can be obtained.

G. Examples Examples of the recording medium according to the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an optical disc, which is an embodiment of a recording medium according to the present invention, together with a recording format.

This optical disk is, for example, a write-once optical disk, a rewritable magneto-optical disk, etc., and is rotated by a spindle motor or the like at a constant angular velocity (CAV), and is recorded on recording tracks provided spirally or concentrically on the disk. Data (information) is now recorded/played on. Furthermore, a sample servo method (or discrete block method) is used as a clock synchronization method when recording/reproducing data. In other words, segments extending from the servo area where servo signals are recorded and the data area where data is recorded are arranged in the track direction, which is the recording/playback direction, and one sector, which is a recording unit of data (information), is composed of multiple segments. One track is composed of a plurality of sectors, and the servo signal recorded in the servo area is reproduced to perform clock synchronization and tracking servo control, and to record/reproduce data.

In FIG. 1, one track of an optical disc 1 is composed of sectors 2 which are n data recording units, and one sector is composed of m segments. Further, one segment is composed of a servo area 3 and a data area 4.

The servo area 3 includes a clock bit 11 for clock synchronization, a pair of so-called wobble bits 12a and 12b for obtaining a tracking error signal, and two pin-nodes for recording a rack address (track number). An access code 13 composed of 13a and 13b is provided in advance at the time of disk formation. In data area 4,
For example, in the case of a magneto-optical disk, data (information) is recorded/reproduced using the magneto-optic effect. Here, a pattern composed of the clock bit 11 and wobble pins 12a and 12b is referred to as a synchronization pattern 10. In the present invention, in order to increase the data area available to the user, the area for recording sector marks, track addresses, and sector addresses (header area) that was conventionally required is deleted, and instead, for example, the above-mentioned access code 1
3 is used to record the track address, and the synchronization pattern 10 and the like are used to record the reference position information on the track, and the track address is written from the access code 10 and the sector address etc. from the reference position information. I'm trying to get information.

Specifically, as shown in FIG. 1, the access code 13 of the servo area 3 has a capacity capable of recording 4-bit information. Therefore, each bit of the track address is changed from the least significant bit side to bits Be, B+, Bx,
..., and the track address is divided and entered into the access code 13. For example, the lower two bits B+Be of the track address (hereinafter expressed as (1, 0) as shown in FIG. 1) are used to address each servo area within one track (i.e.,
write the bits (3, 2) of the track address using the upper two bits of the access code 13 at twice the cycle of the above bits (1, 0);
Bits (5, 4) of the track address are set using the upper 2 bits of the access code 13 (3, 2)
Recording is performed at twice the period of . Continue in the same manner up to the most significant bit of the track address. As a result, the lower side of the track address is recorded more times than the upper side, making it possible to detect and access tracking errors with high accuracy. Further, by recording and forming the upper bits of the track address in this way, faster access in the radial direction is possible than when only the lower bits are used.

That is, in the conventional method of putting the lower 4 bits of the track address into the access code 13, the lower 4 bits of the track address are recorded for each segment, and this address information is stored at the highest speed within the range of 8 tracks/segment. This is the amount of information that can be moved (address information for 16 tracks, but since there are two movement directions, the inner circumferential direction and the outer circumferential direction, there are 8 tracks/segment).

By the way, in the present invention, as described above, track address bits (1, 0) are set for each segment, track address bits (3, 2) are set for every two segments, and track address bits (5, 4) are set for every two segments. Every 4 segments,
Bits (7, 6) of the track address are recorded every 8 segments (the same continues up to the most significant bit). Life 1.
．． Su4ゎ5. Straw. The information is divided into 2 tracks/segment, 4 trunks/segment, and 8 tracks/segment, respectively.
This is the amount of information that can be moved at the maximum speed within a segment, 16 tracks/segment (same goes on up to the most significant bit). Therefore, by recording up to the most significant bit of the track address in the access code,
It becomes possible to use the most significant bit of the track address, which can be moved at the highest speed and over the widest range.

FIG. 2 is a diagram showing a specific example in which bits (5, 4) and bits (1, O) of the track address are included in the access code as described above, with the radial direction of the disk as the vertical direction. The access code value shown in this figure represents the track address in binary, and the hexadecimal value expressed in 4 bits consisting of bits B, Ba, B+, and Bo of the track address represented in binary. For example, when the track address is "0", the access code value is "0", and the track address is r16J (i.e., Bs"0", Ba"'1", Bi""O',
3! , IIQII , B, , "0"Be"0m), the access code is "4"('0 in binary representation)
100"). As shown in FIG. 2, the access codes on adjacent tracks satisfy the characteristics of the Gray code. For example, if the track address is "3" (similarly "19", "35", The characteristics of the Gray code are also satisfied between the access code on the track whose address is "r51J" and the access code on the track whose track address is "4" (similarly "20", "36", and "r52").

Next, in order to record the reference position information on the track in advance, the reference position information on the track is entered using, for example, the synchronization pattern 10 described above.

Specifically, as shown in FIG. 3, as the synchronization pattern 10, for example, a reference pattern different from the conventional pattern P0 (e.g., eight types of reference patterns P to ps having mutually different patterns) is provided, and for example, a track A reference pattern P1 is recorded in advance in the servo area 3 at the beginning of the track, and a conventional pattern P is recorded in all other servo areas 3, so that the beginning of the track can be identified.

Further, for example, when one track is composed of 16 segments, the reference pattern P is placed in the servo area 3 at the beginning of the first sector, which is the first sector of the track, and in the remaining sectors, for example, at the beginning of the third sector. The servo area 3 of the reference pattern P2 is placed in the servo area 3 of the beginning of the fifth sector.
A different reference pattern is pre-recorded for each sector, such as reference pattern P1 (two in this example), and a conventional pattern P0 is pre-recorded in all other servo areas 3, and the beginning of the track is pre-recorded. In addition to making it possible to identify
Even when the reference pattern P1 recorded in the servo area 3 at the beginning of the track cannot be detected due to a defect in the disk, other reference patterns (for example, reference pattern P2) cannot be detected.
to pg) to obtain sector information.

By the way, if it is difficult to select multiple types of reference patterns as described above without affecting other signals within a limited synchronization pattern lo, one type of reference pattern may be used,
This reference pattern is recorded for each of multiple sectors, the reference position information is entered in the above-mentioned access code following this reference pattern, and sector information such as a sector address is obtained using both the reference pattern and the reference position information of the access code. Make it. Note that (2) When the access code does not have a capacity to record sector information such as a sector address, the sector information may be divided and stored in a plurality of access codes.

Figure 4 shows how data is recorded on an optical disc in which track address information is recorded in the access code as described above.
FIG. 2 is a block circuit diagram of main parts of a recording/reproducing device for reproduction.

In FIG. 4, a reproduction signal reproduced from an optical disk that is rotationally driven at a constant angular velocity (CAV) by a spindle motor is supplied to a synchronization pattern detection circuit 21 and an access code reproduction circuit 22 via an input terminal 20. There is. In addition, these synchronization pattern detection circuits 21
The access code reproducing circuit 22 is supplied with a reproduction timing signal reproduced from the clock pin 11 of the servo area 3 from the tie controller 27 .

In the synchronization pattern detection circuit 21, the conventional pattern P0 and the reference pattern P recorded in the servo area 3,
Pg to Pg, that is, all synchronization patterns 10 are detected, and the byte counter 23 that manages time within the segment is initialized. This byte counter 23 counts the number of bytes in the l segment by counting a predetermined clock signal from the timing controller 27, and when it counts up a predetermined number (counts up), a carry signal is sent to the segment counter 24.

In the synchronization pattern detection circuit 21, a reference pattern recorded, for example, in the servo area 3 at the beginning of the track, for example, reference pattern P1, is detected, and a segment counter 24 that manages time in units of segments in the sector and in units of sectors in the track are detected. The sector counter 25, which performs time management, is initialized. This segment counter 24 is
By counting the carry signals from the byte counter 23, the number of segments in one sector is counted.

That is, the byte counter 23 is incremented (increased by 1) every time the byte counter 23 carries a carry, and when a predetermined number (m) has been counted (counted up), a carry signal is sent to the sector counter 25. This sector counter 25 counts the number of sectors (H large n) in one track by counting the carry signal from the segment counter 24. That is, the byte counter 23, the segment counter 24, and the sector counter 25, which are incremented (increase by l) every time the segment counter 24 has a carry, are operated by a predetermined clock signal from the tie-breaking controller 27. Each count information from is sent to the timing controller 27, segment synchronization,
Rotational synchronization such as sector synchronization and track synchronization is achieved.

As mentioned above, the reference pattern P1 is recorded in the first servo area 3 of the first sector, which is the first sector of the track, and in the remaining sectors, the reference patterns P to P are recorded for each of a plurality of sectors. In the case where the servo area 3 is pre-recorded, the servo area 3 at the beginning of the track is
When the reference pattern P1 recorded on the disc cannot be detected due to a defect in the disc, the synchronization pattern detection circuit 21
Other reference patterns detected in (reference pattern P
Sector address (sector number) corresponding to 2 to P.)
is supplied to the sector counter 25 as an initial value, and counting is started from this initial value.

After the rotation is synchronized, the access code reproducing circuit 22 reproduces the track address recorded in the access code, and the reproduced track address is stored in the track address register 26 by a predetermined clock signal from the timing controller 27. be remembered. In addition,
Servo information generation operation and tracking servo control operation are
For example, recording/reproduction management of data (information) is performed using address information such as a track address obtained in 0 or more ways, which are not shown and will not be described since they may be similar to the conventional technology described above. .

FIG. 5 is a block circuit diagram of the main parts of the recording/reproducing apparatus when reference position information on a track is included in one type of reference pattern and access code as described above. This fifth
In the figure, the operations of the byte counter 33 and segment counter 34 are the same as those of the byte counter 23 and segment counter 24 shown in FIG. 4, so a description thereof will be omitted.

After the synchronization pattern detection circuit 31 detects the reference pattern, the access code reproducing circuit 32 reproduces the reference position information recorded in the access code, and the sector address corresponding to this reference position information is set as an initial value. The value is supplied to the counter 35, and counting is started from this initial value.

As described above, by recording all address information such as sector addresses and track addresses in the servo area and eliminating the header area that was previously required, address information etc. can be recorded in all segments when using a disk. There is no data area, and all data areas can be used by the user. Furthermore, by recording all address information in the servo area, it is possible to change the data format of the data area. That is, by fixing the format of the servo area and controlling the count cycles of the segment counter and sector counter, it is possible to change the data format within each track. In other words, if the format of the servo area is unified as described above, even if the specifications of the data area change due to future high-density recording and playback, the track address etc. of the servo area can be used as is. Become.

FIG. 6 shows a block circuit diagram of the main parts of a recording/reproducing apparatus that can vary the data format of the data area in each track.

In FIG. 6, a reproduction signal reproduced from an optical disk rotationally driven at a constant angular velocity (CAV) by a spindle motor is transmitted via an input terminal 40 to a synchronization pattern detection circuit 41, an access code reproduction circuit 42, and a servo information generation circuit. 48 respectively. In addition, these synchronization pattern detection circuit 41 and access code regeneration circuit 4
2. The servo information generation circuit 48 is supplied with a reproduction timing signal reproduced from the clock bit 11 of the servo area 3 from the timing controller 47.

Further, in order to set the number of sectors and segments in a track, the number of segments in one sector and the number of sectors in one track are written from the controller 50 to the register 5152, respectively. The set values from these registers 51 and 52 are sent to a segment counter 44 that manages time in units of segments within a sector, and a sector counter 45 that manages time in units of sectors within a track.

In the synchronization pattern detection circuit 41, the synchronization pattern 10 (conventional pattern P and reference pattern) recorded in the servo area 3 is detected, and a byte counter 43 for managing time within a segment, the segment counter 4
4. The sector counter 45 is initialized. This byte counter 43 counts the number of bytes in one segment by counting a predetermined clock signal from the timing controller 47, and when it counts up a predetermined number (counts up), a carry signal is sent to the segment counter 44. This segment counter 44 counts the carry signal from the byte counter 43 to
Count the number of segments within a sector. That is, each time the byte counter 43 carries, it is incremented (
When the number of segments in one sector set by the controller 50 is counted (counted up), a carry signal is sent to the sector counter 45. This sector counter 45 counts the number of sectors within one track by counting the carry signal from the segment counter 44. That is, the segment counter 44 is incremented (increased by 1) each time the segment counter 44 carries, and counts the number of sectors in one track set by the controller 50. In other words, the segment counter 44 and the sector counter 45 are set to 1 by the controller 50.
The counting operation is repeated using the number of segments of sectors and the number of sectors of one track as cycles.

When the reference pattern is detected in the synchronization pattern detection circuit 41 and the reference position information recorded in the access code is generated in the access code reproducing circuit 42, the value of this reference position information is sent to the decoder 54. Further, the number of sectors and the number of segments installed by the controller 50 are supplied to the decoder 54 via the register 53, and depending on the number of segments and the value corresponding to the number of sectors and the value of the reference position information, The initial value of the sector counter 45 is set from the decoder 54.

The byte counter 43, segment counter 44, and sector counter 45 are operated by a predetermined clock signal from the timing controller 47, and each count information from these counters is transmitted to the timing controller 47.
Rotation synchronization such as segment synchronization, sector synchronization, and track synchronization is performed.

After the rotation is synchronized, the access code reproducing circuit 42 reproduces the track address recorded in the access code 13 of the servo area 3, and stores it in the track address register 46 using a predetermined clock signal from the timing controller 47. Ru.

In the servo information generation circuit 48, servo information such as tracking servo control is generated by the reproduced signals of the wobble pits 12a and 12b in the servo area 3, and this servo information is converted into servo information by a predetermined clock signal from the timing controller 47. It is stored in register 49. Then, tracking servo control is performed based on this servo information.

That is, the current position on the track can be specified based on the number of segments, the number of sectors, the value of the segment counter 44 (count value), and the value of the sector counter 45 (count value) set by the controller 50. . The number of segments set by the controller 50,
The number of sectors and the format of the track currently being recorded/played.
The access code can be played even if the mat is different.

Even when tracking servo control is not applied, the upper part of the track address recorded in the access code can be reproduced. Furthermore, the access code can be reproduced even in the initial state of rotation of the optical disc, during access operation in the radial direction, and when there is a defect in the disc. Furthermore, when recording/reproducing, the number of segments, number of sectors, and initial value of the sector counter 45 can be set by the controller 50 in accordance with a desired data format.

In this way, by reproducing the track address recorded in the access code of the servo area and detecting, for example, the beginning of the track using the synchronization pattern of the servo area, address information such as the track address, sector address, etc. can be obtained. Therefore, it is possible to eliminate the area (header area) for recording sector marks, sector addresses, and track addresses that was previously required, and it is possible to increase the recording capacity of data (information) that can be used by the user. . Additionally, the sector mark detection circuit, sector address reproducing circuit, and track address reproducing circuit can be eliminated from the recording/reproducing device.
The cost of the playback device can be reduced. Furthermore, by dividing the track address and lengthening the recording cycle of the upper bits of the track address as described above, all track addresses can be recorded with the current access code eMM, enabling high-speed access in the radial direction. becomes. In addition, there are fewer types of reference patterns for detecting the reference position on the track, and the influence on servo signals is small.Also, by recording all address information such as track addresses in the servo area, it is possible to On a disk, the data format in the trunk (e.g. data capacity on the inner and outer circumference of the disk)
It becomes possible to change. That is, even if the specifications of the data area change, the specifications of the servo tiI area do not need to be changed and can be used as they are.

Note that the present invention is not limited to the above-mentioned embodiments, and for example, the recording medium may include, in addition to magneto-optical disks, for example, organic dye-based optical disks, various write-once disks, overwritable disks,
Applicable to optical cards, magneto-optical cards, etc.

Effects of the H8 invention As is clear from the above explanation, by reproducing the track address recorded in the access code of the servo area and detecting the beginning of the track using the synchronization pattern of the servo area, etc. , track address, sector address, etc. can be obtained. Therefore, it is possible to eliminate the area (header area) for recording sector marks, sector addresses, and track addresses that was previously required, and it is possible to increase the recording capacity of data (information) that can be used by the user. . Further, the sector mark detection circuit, sector address reproducing circuit, and track address reproducing circuit can be omitted from the recording/reproducing apparatus, and the cost of the recording/reproducing apparatus can be reduced. Furthermore, the track address can be divided into
By lengthening the recording cycle of the upper bits of the link address, all track addresses can be recorded in the current access code area, allowing high-speed access in the radial direction. In addition, there are only a few types of reference patterns for detecting the reference position on the track, which has little effect on servo signals, and by recording all address information such as track addresses in the servo area, it is possible to It becomes possible to change the data format within a track (for example, the data capacity on the inner and outer circumferences of the disc). That is, even if the specifications of the data area change, the specifications of the servo area do not need to be changed and can be used as they are.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an optical disc as an embodiment of the recording medium according to the present invention together with its recording format, FIG. 2 is a diagram showing a specific example in which a track address is recorded in an access code, and FIG. FIG. 4 is a diagram showing a specific example of a reference pattern, and FIG. FIG. 5 is a block circuit diagram of a main part of a second embodiment of a recording/reproducing apparatus for recording/reproducing data on a recording medium according to the present invention, and FIG. 6 is a block circuit diagram for recording/reproducing data on a recording medium according to the present invention. / Third part of the recording/playback device to be played back
FIG. 7 is a diagram showing a conventional optical disc along with a recording format; FIG.
FIG. 8 is a diagram showing a conventional recording format of an access code, and FIG. 9 is a block circuit diagram of a main part of a conventional recording/reproducing apparatus. Synchronous pattern detection circuit Access code regeneration circuit Segment counter Sector counter Track address register

Claims (2)

[Claims] (1) In a sample servo type recording medium in which a segment consisting of a servo area where servo signals are recorded and a data area where data is recorded is arranged in the track direction which is the recording/playback direction, an access code is placed in the servo area. 1. A recording medium, wherein track address information is divided into the access code. (2) The recording medium according to claim (1), wherein reference position information on the track is stored in the servo area.