JP2002269759A - Optical disk and method for formatting the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk in which tracking switching areas are aligned on a same radial line of a disk in whole track of a constant linear velocity(CLV) format system, i.e., at a length of line corresponding to one turn of the disk of a spiral land track or a groove track and to provide a method for formatting the optical disk. SOLUTION: Each track of the land track LT an the groove track GT is formed of tracking switching areas LG and GL which switch the trackings for the land track LT and the groove track GT, a plurality of sectors having a sector length of the CLV system, and variable length dummy areas LD and GD, and the tracking switching areas LG and GL are aligned on the same radial line on the optical disk and formatted by varying the length of the dummy areas LD and GD. Thus, an L/G type format with which information is recorded and reproduced by switching the tracking at every track is build as a format which is nearer to the CLV method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rewritable optical disk, and more particularly to a CL which is suitable for recording and reproducing a large amount of data.
V method (constant linear velocity method) and L / G recording method (land
And a groove recording method) and a method of formatting the optical disk.

[0002]

2. Description of the Related Art In recent years, DVD-ROMs, DVD-Rs, DVD-RAMs, and the like have attracted attention as large-capacity optical disk media. In order to increase the storage capacity, L / L, in which both the land track and the groove track are used as information tracks, are increasingly narrowed and / or pitched.
Studies have been made on the format of the G recording system, or the multi-layering of the information surface of the optical disk.

Several examples of the conventional L / G recording system which have been studied as described above are as follows.
For example, as a first example, according to Japanese Patent Application Laid-Open No. 7-14172, the CLV rotation is performed by reading address information recorded as a groove waveform not only at the time of recording / reproducing a land but also at the time of recording / reproducing a land. There have been proposals to sufficiently increase the recording density. However, in the recording / reproducing method, when recording is performed from a groove (or land), reverse marker information is recorded from the outer periphery, the disc rotation direction, the tracking error signal polarity and the wobble signal detector are switched, and the land (or groove) is recorded. )
Recording is performed from the outer peripheral side to the inner peripheral side.

As a second example, according to Japanese Patent Application Laid-Open No. Hei 9-73665, the format of a land / groove recording phase change optical medium is substantially aligned in a radial direction with a preformat portion in each zone. Modified CLV
(MCLV) or modified CAV (constant angular velocity method) (MCAV), and the groove depth is 0.15 (λ /
n) to 0.2 (λ / n).

As a third example, Japanese Patent Application Laid-Open No. 9-161274
According to the publication, in order to recognize a header portion provided at a head portion of an information sector, in an optical disc in which an information recording track to be recorded on both a land and a groove is divided into a plurality of zones in accordance with a radial position. Has been proposed for a method of formatting a recognition pattern.

Incidentally, with respect to increasing the storage capacity, a CLV format in which the linear density of information is constant can be said to be advantageous. However, when trying to configure the L / G format in the CLV format, there is a problem that the positional relationship of sectors on adjacent tracks is constantly changed.

[0007] This will be described. Now, in the CLV format formed on spiral tracks of equal pitch formed by CLV driving, the line length difference between adjacent tracks is: line length difference between adjacent tracks = 2πP = constant (where P
Is the track pitch), and increases by a fixed amount as the track gets closer to the outer periphery.
When sectors having a fixed length are continuously formed on such a track, the phase difference between sectors on adjacent tracks (distance between heads of sectors on adjacent tracks) is monotonous as shown in FIG. Is repeatedly increased and decreased. For example, FIG. 5 shows that the number of sectors on track Nb is one more than the number of sectors on track Na.

As described above, generally, in the CLV format, the sector positions on adjacent tracks rarely align on the disk radius line, and the LAV in the MCAV or MCLV format as in the second and third proposals described above.
If the format configuration is not different from the true CLV format as in the / G format configuration, the complete C
The L / G format cannot be configured on the LV format.

[0009]

Here, in the case of the first proposed example described above, the CLV format has an L / G format configuration using lands and grooves as information tracks. Land tracking and groove tracking are alternately switched for each track and are not performed uniformly from the inner circumference to the outer circumference, but are turned back from the outer circumference to the inner circumference, including switching of the disk rotation direction. , Not accessible.

In this respect, in the case of the second and third proposals described above, information can be recorded and reproduced while switching between lands and grooves for each track. However, the arrangement of sectors belongs to MCAV or MCLV, and CLV It is inferior to the format in the linear density of information.

Accordingly, the present invention basically provides an L / G format capable of recording and reproducing information while switching between tracking of land tracks and tracking of groove tracks for each track. CLV
It is an object of the present invention to provide an optical disc and a format method thereof that can improve the accessibility in the format.

More specifically, in all tracks in the CLV format system, that is, in a line length corresponding to one revolution of a spirally formed land track or groove track, the tracking switching area is formed on the same radius line on the disc. An object of the present invention is to provide an optical disk that can be aligned and a method of formatting the optical disk.

Further, the present invention provides an optical disk which is useful for identifying a track number when accessing a certain track, enables a search operation before the linear velocity is stabilized, and enables a high-speed access operation in the CLV format, and a format method therefor. The purpose is to:

[0014]

According to a first aspect of the present invention, there is provided an optical disk formatting method for an optical disk in which land tracks and groove tracks are formed in a spiral shape. A tracking king switching area for switching tracking with respect to the land track and the groove track, a plurality of sectors having a sector length of the CLV method, and a dummy area having a variable length. The tracking is performed by changing the length of the dummy area. The switching area is aligned on the same radius line on the optical disc and formatted.

Therefore, since the tracking switching area is formatted so as to be aligned on the same radius line on the optical disk by using the variable length dummy area, land track tracking and groove track tracking are switched for each track. However, it is possible to construct an L / G format capable of recording and reproducing information as a format close to the CLV format. In particular, switching between tracking to a land track and tracking to a groove track can be smoothly performed in a tracking switching area aligned on the same radius line of the optical disc.

According to a second aspect of the present invention, in the optical disk formatting method according to the first aspect, in a track in which the length of the dummy area has reached a sector length, formatting is performed by increasing the number of sectors on the track.

Therefore, in realizing the first aspect of the present invention, since there is no dummy area longer than the sector length, a reduction in the number of sectors due to the use of the dummy area, that is, a reduction in the recording capacity is minimized. it can.

According to a third aspect of the present invention, in the optical disk formatting method according to the second aspect, when a track pitch between the land track and the groove track is P, the sector length on the track is 2πP. The length is set to an integral multiple of the basic length, and the lengths of the tracking switching area and the dummy area are also set to integral multiples of the basic length of 2πP.

Therefore, in each zone divided by the difference in the number of sectors in each track on the optical disk, the sector length and the length of the dummy area, the sector length and the length of the tracking switching area, or Since the format is such that the ratio between the length of the dummy area and the length of the tracking switching area is uniquely determined, if the approximate positions are known, the current track can be specified by calculating these ratios, and the linear velocity can be determined. A search operation before stabilization becomes possible, and a high-speed access operation in the CLV format becomes possible. In particular, since the length of the track king switching area is also an integral multiple of the basic length of 2πP, the ratio of the length of the track king switching area to the length of each track is also a different integer value for each track, and the current track can be specified with higher accuracy. It becomes possible.

According to a fourth aspect of the present invention, in the method for formatting an optical disk according to the third aspect, zones corresponding to zones divided by a difference in the number of sectors in each track are provided.
The recording is performed with a specific relationship between the tracking switching area and the dummy area.

Therefore, since the tracking switching area and the dummy area are formatted so as to have a specific relationship in correspondence with each zone divided by the difference in the number of sectors in each track on the optical disc, By recognizing the specific relationship, the zone where the current track exists can be specified, the search operation can be performed before the linear velocity is stabilized, and the high-speed access operation in the CLV format can be performed.

According to a fifth aspect of the present invention, in the optical disk formatting method according to the fourth aspect, the dummy area is divided and arranged before and after the tracking switching area, and the dummy area is arranged after the tracking switching area. By changing the length of the area corresponding to the zone, a specific relationship is provided.

Therefore, as a method of giving a specific relationship between the tracking switching area and the dummy area, the dummy area is divided and arranged before and after the tracking switching area.
By changing the length of the dummy area disposed after the tracking switching area in accordance with the zone, the ratio of the length of the tracking switching area to the length of the dummy area after the tracking switching area is easily and simply used. It is a specific relationship that is easy to recognize.

An optical disc according to a sixth aspect of the present invention is an optical disc in which land tracks and groove tracks are formed in a spiral shape, wherein each of the land tracks and the groove tracks is composed of the land tracks and the groove. It is composed of a track king switching area for switching tracking with respect to a track, a plurality of sectors having a CLV sector length, and a dummy area having a variable length. The variable length of the dummy area makes the tracking switching area identical on the optical disc. Formatted aligned on the radius line.

Therefore, since the tracking switching area is formatted so as to be aligned on the same radius line by using the variable length dummy area, information tracking is performed for each track while switching between land track tracking and groove track tracking. It is possible to construct an L / G format capable of recording and reproduction as a format close to the CLV format. In particular, switching between tracking to a land track and tracking to a groove track can be smoothly performed in a tracking switching area aligned on the same radius line.

According to a seventh aspect of the present invention, in the optical disk according to the sixth aspect, in a track in which the length of the dummy area reaches a sector length, the number of sectors on the track is increased.

Therefore, in realizing the invention of claim 6, since there is no dummy area longer than the sector length, it is possible to minimize the decrease in the number of sectors due to the use of the dummy area, that is, the reduction in the recording capacity. it can.

According to an eighth aspect of the present invention, in the optical disk according to the sixth or seventh aspect, when a track pitch between the land track and the groove track is P, a sector length on the track is 2πP. The length is set to an integral multiple of the length, and the lengths of the tracking switching area and the dummy area are also set to integral multiples of the basic length of 2πP.

Therefore, in each zone divided by the difference in the number of sectors in each track, for each track,
Since the format is such that the sector length and the length of the dummy area, the sector length and the length of the tracking switching area, or the ratio of the length of the dummy area and the length of the tracking switching area are uniquely determined, the approximate position is determined. If you know,
By determining these ratios, the current track can be specified, and a search operation before the linear velocity becomes stable becomes possible.
High-speed access operation in the V format becomes possible. In particular, since the length of the track king switching area is also an integral multiple of the basic length of 2πP, the ratio of the length of the track king switching area to the length of each track is also a different integer value for each track, and the current track can be specified with higher accuracy. It becomes possible.

According to a ninth aspect of the present invention, in the optical disk of the eighth aspect, the track king switching area and the dummy area are specified to correspond to zones divided by the difference in the number of sectors in each track. It is formatted to have a relationship.

Accordingly, since the tracking switching area and the dummy area are formatted so as to have a specific relationship corresponding to each zone divided by the difference in the number of sectors in each track, the specific By recognizing the relationship, the zone where the current track exists can be specified, the search operation can be performed before the linear velocity is stabilized, and the high-speed access operation in the CLV format can be performed.

According to a tenth aspect of the present invention, in the optical disk according to the ninth aspect, the dummy area is divided and arranged before and after the track king switching area, and a length of the dummy area arranged after the track king switching area. A specific relationship is provided by changing the distance in accordance with the zone.

Therefore, as a method of giving a specific relationship between the tracking switching area and the dummy area, the dummy area is divided and arranged before and after the tracking switching area.
By changing the length of the dummy area disposed after the tracking switching area in accordance with the zone, the ratio of the length of the tracking switching area to the length of the dummy area after the tracking switching area is easily and simply used. It is a specific relationship that is easy to recognize.

[0034]

FIG. 1 shows a first embodiment of the present invention.
A description will be given based on FIG. First, a CLV formatting method for a rewritable optical disk according to the present embodiment will be described with reference to FIG. The present embodiment is applied to the L / G recording method, and it is assumed that the land track LT and the groove track GT are formed in a spiral shape. Here, in each of the tracks LT and GT, a plurality of sectors S, variable length dummy areas LD and GD whose lengths are set to be changed for each track, and tracking area switching areas LG and GL are configured. ing. The tracking area switching area LG is an area for switching tracking from the land track LT to the groove track GT, and the tracking area switching area GL is an area for switching tracking from the groove track GT to the land track LT.

The dummy areas LD and GD do not have a sector structure (do not function as sectors) and do not record or reproduce data. The dummy areas LD and GD have only a tracking function so that tracking is not lost. By appropriately and variably setting the lengths of these dummy areas LD and GD for each track, the tracking area switching areas LG and GL are located on the optical disc 1 as shown in FIG.
As shown in the figure, the data is formatted so as to be aligned on the same radius line.

At this time, it is desirable from the viewpoint of information density that the length of the dummy areas LD and GD is set not to be longer than the sector length on any track. Therefore, when the length of the dummy areas LD and GD becomes equal to the sector length, the format is performed so as to increase the number of sectors in the track.

As described above, the tracking switching area L
Since G and GL are aligned on the same radius line, a command to switch between the land track LT and the groove track GT is issued in the tracking switching areas LG and GL, so that all the land track areas and all the grooves formed by the CLV format. Track areas can be tracked alternately and continuously, and L
/ G recording / reproduction becomes possible.

In this embodiment, when the track pitch between the land track LT and the groove track GT is P, the sector length on each track is 2
The length is set to an integral multiple of the basic length of πP, and the lengths of the tracking switching regions LG and GL and the dummy regions LD and GD are also set to integral multiples of the basic length of 2πP.

As described above, the line length of each track in the CLV format increases by a length equal to the basic length 2πP toward the outer track. Therefore, the configuration of each track is such that the dummy areas LD, G
D is increased by a length of 2πP, and the dummy regions LD, G
When the total length of D is equal to the sector length, the number of sectors is increased by one to eliminate the dummy areas LD and GD. After that, 2πP
The length of the dummy areas LD and GD is increased by a certain length, and the same is repeated each time the length becomes equal to the sector length.

In the CLV format configured as described above, as shown in FIG. 3, the number of sectors in a track is increased for each Ns (Ns is an integer value obtained by (sector length) / 2πP) tracks. Is formed. That is, if a group of tracks having the same number of sectors in a track is referred to as a "zone," the configuration of the dummy area for each zone is exactly the same.

Here, as far as the zone is concerned, the sector length and the length of the dummy area, the sector length and the length of the tracking switching area, or the ratio of the length of the dummy area to the length of the tracking switching area are as follows: The value is unique to each track.
Therefore, in the optical disk drive, when the approximate position is known when specifying the current track, the track can be specified by obtaining these ratios.

Incidentally, the tracking switching areas LG,
The length of the GL does not necessarily need to be an integral multiple of the length of 2πP, and may be any fixed length. If the length is 2πP (or πP), the tracking switching area LG , GL have a different integer value for each track in the zone, thereby enabling more accurate track identification.

A second embodiment of the present invention will be described with reference to FIG. The same portions as those described in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As described above, in one optical disc 1, several zones are formed for each Ns track. In the present embodiment, it is possible to specify the zone by formatting such a zone so as to have a specific relationship between the tracking switching area and the dummy area corresponding to the zone. Things.

For this purpose, in the present embodiment, the dummy area is divided and arranged before and after the tracking switching area, and the length of the dummy area arranged after the tracking switching area is changed according to the zone. They have a specific relationship.

Specifically, the minimum length of the dummy area in each track is made equal to (number of zones -1) × 2πP formed on the optical disk 1, and the dummy arranged after the tracking change area corresponding to the zone. The length of the area is changed. In the illustrated example, for simplicity of description, the case where the number of zones is three is shown, and in zone 1, the length of the dummy area disposed after the tracking change area is set to 0 (= 0 × 2πP). In zone 2, the length of the dummy area disposed after the tracking change area is 2πP (= 1 × 2πP), and in zone 3, the length of the dummy area disposed after the tracking change area is 2πP. × 2πP. According to the variable length of the dummy area arranged after such a tracking change area,
The length of the dummy area arranged before the tracking change area is also varied, and the total length of the dummy areas between the zones is set to be the same.

The dummy area may be located anywhere within the track. This is because if the sum of the sector length in the track, the length of the dummy area, and the length of the tracking switching area has a track configuration as described in FIG. 3, the tracking switching area is aligned on the same radius line. This is because it can be done.

In any case, by determining the ratio between the length of the tracking switching area and the length of the dummy area after the tracking switching area, the zone can be specified based on a specific relationship.

Therefore, according to the present embodiment, the format is set by giving a specific relationship between the tracking switching area and the dummy area corresponding to each zone divided by the difference in the number of sectors in each track. Therefore, by recognizing the specific relationship, the zone where the current track exists can be specified, the search operation can be performed before the linear velocity is stabilized, and the high-speed access operation in the CLV format can be performed. At this time, as a method of giving a specific relationship between the tracking switching area and the dummy area, the dummy area is divided and arranged before and after the tracking switching area, and the length of the dummy area arranged after the tracking switching area is divided. Is changed corresponding to the zone, and a specific relationship that is simple and easily recognizable is obtained by utilizing the ratio of the length of the tracking switching area to the length of the dummy area after the tracking switching area.

[0050]

According to the optical disk formatting method of the first aspect of the present invention, the tracking switching area is formatted so as to be aligned on the same radial line on the optical disk by using the variable length dummy area. It is possible to construct an L / G format capable of recording and reproducing information while switching between land track tracking and groove track tracking for each track as a format close to the CLV format. The switching between the tracking to the land track and the tracking to the groove track can be smoothly performed in the tracking switching area arranged in the same manner.

According to a second aspect of the present invention, in the optical disk formatting method according to the first aspect, in a track in which the length of the dummy area has reached the sector length, formatting is performed by increasing the number of sectors on the track. Therefore, in realizing the first aspect of the present invention, there is no dummy area longer than the sector length, and a reduction in the number of sectors due to the use of the dummy area, that is, a reduction in the recording capacity can be minimized. .

According to a third aspect of the present invention, in the optical disk formatting method according to the second aspect, in each zone divided by a difference in the number of sectors in each track on the optical disk, a sector is provided for each track. The format is such that the length and the length of the dummy area, the sector length and the length of the tracking switching area, or the ratio of the length of the dummy area and the length of the tracking switching area are each uniquely determined, so the approximate positions are divided. For example, by determining these ratios, the current track can be specified, a search operation can be performed before the linear velocity is stabilized, and a high-speed access operation in the CLV format can be performed. In particular, the length of the track switching area becomes 2πP. Because the length is an integral multiple of the basic length, the ratio to the length of the tracking switching area is also Becomes different integers track, certain of the current track can be performed with higher accuracy.

According to the fourth aspect of the present invention, in the optical disk formatting method according to the third aspect, a tracking switching area is provided corresponding to each zone divided by a difference in the number of sectors in each track on the optical disk. Since the format is provided with a specific relationship with the dummy area, the zone where the current track exists can be identified by recognizing the specific relationship, and the search operation before linear velocity stabilization becomes possible. , CLV format.

According to a fifth aspect of the present invention, in the method of formatting an optical disk according to the fourth aspect, the dummy area is set to have a specific relationship between the tracking switching area and the dummy area. By dividing the dummy area before and after and changing the length of the dummy area arranged after the tracking switching area in accordance with the zone, the ratio of the length of the tracking switching area to the length of the dummy area after this tracking switching area is changed. , A specific relationship that is simple and easily recognizable.

According to the optical disc of the sixth aspect of the present invention, since the tracking switching area is formatted so as to be aligned on the same radius line using the variable length dummy area, the tracking of the land track can be performed for each track. The format of the L / G system that can record and reproduce information while switching between tracking of groove tracks is C
It is possible to construct a format close to the LV format, and in particular, it is possible to smoothly switch between tracking to a land track and tracking to a groove track in tracking switching areas aligned on the same radius line.

According to the seventh aspect of the present invention, in the optical disk according to the sixth aspect, in a track in which the length of the dummy area has reached the sector length, the number of sectors on the track is increased and the format is increased. In realizing the invention of claim 6, since there is no dummy area longer than the sector length, a decrease in the number of sectors due to the use of the dummy area, that is, a decrease in the recording capacity can be minimized.

According to the eighth aspect of the present invention, in the optical disk according to the sixth or seventh aspect, in each zone divided by a difference in the number of sectors in each track, a sector length and a dummy area are provided for each track. , The length of the sector and the length of the tracking switching area, or the ratio of the length of the dummy area and the length of the tracking switching area are each uniquely determined. By determining the ratio, the current track can be specified, the search operation can be performed before the linear velocity is stabilized, and the high-speed access operation in the CLV format can be performed. The ratio to the length of the track king switching area is also different for each track. Ri, certain of the current track can be performed with higher accuracy.

According to the ninth aspect of the present invention, in the optical disk according to the eighth aspect, a zone is provided between the tracking switching area and the dummy area corresponding to each zone divided by the difference in the number of sectors in each track. Recognizing the specific relationship, the zone in which the current track exists can be specified by recognizing the specific relationship, the search operation can be performed before the linear velocity is stabilized, and the high-speed access in the CLV format can be performed. Operation becomes possible.

According to the tenth aspect, the ninth aspect is provided.
In the optical disc described above, as a method of giving a specific relationship between the tracking switching area and the dummy area, the dummy area is divided and arranged before and after the tracking switching area, and the dummy area is arranged after the tracking switching area. By changing the length in accordance with the zone, a specific relationship that is simple and easily recognizable is obtained by utilizing the ratio of the length of the tracking switching area to the length of the dummy area after the tracking switching area.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a formatting method according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a formatted optical disk.

FIG. 3 is a schematic diagram for explaining a more practical formatting method.

FIG. 4 is a schematic diagram for explaining a formatting method according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram showing how a phase difference between sectors on adjacent tracks changes in a general CLV format.

[Explanation of symbols]

 1 Optical disc LD, GD Dummy area LG, GL Tracking switching area

Claims (10)

[Claims] 1. An optical disc having a land track and a groove track formed in a spiral shape, a track king switching area for switching each track of the land track and the groove track to track the land track and the groove track. And a plurality of sectors each having a sector length of the CLV method and a dummy area having a variable length. By changing the length of the dummy area, the tracking switching area is aligned on the same radius line on the optical disc and formatted. Formatting method for optical discs. 2. The optical disk formatting method according to claim 1, wherein in a track in which the length of the dummy area has reached the sector length, formatting is performed by increasing the number of sectors on the track. 3. When the track pitch between the land track and the groove track is P, the sector length on the track is set to an integral multiple of a basic length of 2πP, and the track king switching area is set. 3. The method according to claim 2, wherein the length of the dummy area is set to an integral multiple of the basic length of 2πP. 4. A format in which a specific relationship is provided between the track switching area and the dummy area in accordance with a zone divided by a difference in the number of sectors in each track. 3. The method for formatting an optical disc according to item 3. 5. A specific relationship by dividing the dummy area before and after the tracking switching area, and changing the length of the dummy area arranged after the tracking switching area in accordance with the zone. 5. The method for formatting an optical disc according to claim 4, wherein the format is provided. 6. An optical disk having a land track and a groove track formed in a spiral shape, wherein each track of the land track and the groove track switches tracking between the land track and the groove track. A switching area, a plurality of sectors having a CLV sector length, and a dummy area having a variable length. The tracking switching area is formatted and aligned on the same radius line on the optical disc by changing the length of the dummy area. Optical disc. 7. The optical disk according to claim 6, wherein in the track in which the length of the dummy area has reached the sector length, the number of sectors on the track is increased. 8. When the track pitch between the land track and the groove track is P, the sector length on the track is set to an integral multiple of a basic length of 2πP, and the track king switching area is set. 8. The optical disk according to claim 7, wherein the length of the dummy area is set to be an integral multiple of the basic length of 2πP. 9. The recording medium according to claim 8, wherein the track switching area and the dummy area are formatted so as to have a specific relationship in correspondence with zones divided by the number of sectors in each track. optical disk. 10. A specific relationship, wherein the dummy area is divided and arranged before and after the tracking switching area, and the length of the dummy area arranged after the tracking switching area is changed corresponding to the zone. 10. The optical disk according to claim 9, wherein the optical disk is provided.