KR100729330B1 - Optical disc - Google Patents

Abstract

A plurality of grooves G and a plurality of lands L are alternately formed, and the address data recording region has a pair of wobbling portions 31a and 31b having the same phase on both sidewalls of the groove G. FIG. ) Is formed. As a result, a push-pull signal having a large amplitude is obtained, which is advantageous for increasing the data recording density.

Optical disc, groove, land, address data recording area, phase, amplitude, wobbling portion, push-pull signal, data recording density

Description

Optical Disc {OPTICAL DISC}

The present invention relates to an optical disc. The term "optical disk" as used herein refers to a disk capable of recording and / or reproducing data by using optical means. In addition to a read-only negotiated optical disk such as a CD-ROM, an optical magnetic recording method and an image may be used. It is a broad concept that also includes a disc of a type that can write data by a change method or an organic dye change method.

The optical disk is increasing in density, and as an example of the magneto-optical disk, AS-MO (Advanced Storaged Magneto Optical Disk) is a standard of the magneto-optical disk. The magneto-optical disk of this standard has a storage capacity of about 6 GB on one side of a diameter of 120 mm. As shown in FIG. 7, this magneto-optical disk has tracks formed by alternately forming grooves G and lands L in the radial direction (arrow Ra direction). In each track, an area for forming a plurality of fine clock marks 70 at regular intervals in the circumferential direction of the magneto-optical disk is formed, and each track is divided into a plurality of segments by this area. The plurality of segments include an address segment 8 and a data segment 9, and one frame is composed of one address segment 8 and 38 data segments 9. The data segment 9 is an area in which the user records data by the magneto-optical recording method, whereas the address segment 8 is an area in which address data such as a track address is recorded.

As shown in FIG. 8, the recording area of the magneto-optical disk is divided into a plurality of bands B (zones), and a plurality of frames are arranged in each band B in the radial direction and the circumferential direction. In the circumferential direction, as shown in FIG. 9, it arranges from frame 1 to the frame n, and if it is one round, it becomes frame 1. Within each band B, the numbers (frame addresses) of the plurality of frames arranged in the radial direction are the same. Address data recorded in the address segment 8 shown in FIG. 7 includes a frame address, a band address, and a track address.

As a writing method of the address data in the address segment 8, a so-called wobble method is employed in which the wobble part 80 is formed on one sidewall of the groove G. In addition, in the figure, the shape of the wobbling part 80 is shown typically. This also applies to the other accompanying drawings of FIGS. 1 to 6 described later. Among the address data, for example, two tracks in one address segment 8 for the purpose of accurate reading of track addresses such as tracks N, (N + 1), or (N + 2) of the groove G are performed. The wobbling portions 80a and 80b are arranged in the disk circumferential direction. These two wobbling portions 80a and 80b are formed in a staggered manner formed separately on each of the pair of side walls of the groove G. In such a staggered system, even when one of the two wobbling portions 80a and 80b becomes difficult to detect when the magneto-optical disk is tilted, the other side can be detected, thus ensuring the reading of the address data. It is planned.

The push-pull method is used to read the above address data. Briefly explaining this push-pull method, first, as shown in FIG. 10, when the laser light focused by the objective lens 60 is irradiated onto the uneven surface on which the land L and the groove G are formed, and the light is reflected, Positive and negative reflected diffracted light R1 is generated. As a result, in addition to the direct reflection light R0, these reflection diffracted light R1 is also incident on the objective lens 60. Such returned light is received by the two-segment detector 61 having two light receiving areas 61a and 61b, and further corresponds to the amount of received light in the two light receiving areas 61a and 61b output from the detector 61. The difference between one signal SG1, SG2 is taken. This signal is a push-pull signal, and based on this signal, the wobble amount of the part to which the laser beam was irradiated among the wobble parts can be determined.

The pattern of the magneto-optical disk having the address segment 8 and the data segment 9 is exposed by moving the laser beam focused by the objective lens in a radial direction while rotating the glass disk coated with the photoresist. It is also formed by performing the phenomenon. At the time of exposure, one laser beam is divided into two beams, and when exposing a portion corresponding to the wobbling portion 80, control is performed to wobble only one of these two beams. In this way, one side wall is wobbled and the side wall opposite to it can form the groove G which is non-wobbled.

However, the above conventional technologies have the following problems.

First, in the AS-MO standard magneto-optical disk, if the track pitch is 0.6 µm, and the pitch is about this level, the wobbling portion 80 is appropriately formed on one sidewall of the groove G by using the two laser beams described above. can do. By the way, for the purpose of further increasing the data recording density, for example, in order to narrow the track pitch to about 0.3 占 퐉, the wobbling portion 80 of the groove G is appropriately formed by the method using the two laser beams. It becomes difficult to do it. This is because, if the center spacing of these beam spots is made small, the degree of overlap thereof becomes large, which is substantially the same as one beam spot.

Second, in the AS-MO standard magneto-optical disk, a red laser having a wavelength of about 650 nm is used. On the other hand, in order to further increase the density of the magneto-optical disk, it is desired to reduce the beam spot by using a blue laser having a shorter wavelength (for example, about 405 nm). By the way, when the blue laser is used, since the sensitivity of the detector is lowered than when the red laser is used, the detection of the wobbling portion 80 may be inaccurate. In particular, in the optical detection system of the magneto-optical disk device, since the optical detector is divided into the magneto-optical signal detection and the servo signal detection, the amount of light used for the detection of the wobbling portion 80 is reduced, and the detection is inaccurate. Easy to be In addition, in order to increase the S / N of the magneto-optical signal, it is necessary to reduce the amount of light for the servo and increase the amount of light for the detection of the magneto-optical signal. Therefore, the tendency becomes stronger.

It is an object of the present invention to provide an optical disk which can solve or alleviate the above problems.

An optical disk provided by the present invention is an optical disk in which a plurality of grooves and a plurality of lands are alternately formed in a disk radial direction, and in the plurality of grooves, an address data recording area by wobble is formed. The address data recording area is characterized in that a pair of wobbling portions of the same phase are formed on both sidewalls of the groove.

Preferably, the plurality of grooves have a configuration in which a pair of wobbling portions of the same phase are formed for each groove adjacent to the disc radial direction, and a portion sandwiched by these pairs of wobbling portions is formed in each of the lands. .

Preferably, the address data recording area formed in the plurality of grooves includes a first recording area indicating individual addresses of the grooves, and a second recording area indicating addresses of other grooves adjacent to the grooves, The grooves have a configuration in which a first recording area of one groove and a second recording area of another groove adjacent thereto face each other with the land interposed therebetween, and these wobbling portions have the same phase. have.

Preferably, the first and second recording regions of the plurality of grooves are formed in an arrangement shifted in the disc circumferential direction between grooves adjacent to the disc radial direction, and the first and second interposed between the lands. The portions facing the recording areas are configured not to be adjacent to each other in the disc radial direction.

Preferably, the plurality of grooves are configured such that the first to third grooves are arranged repeatedly in the disc radial direction and have a non-track address area in which recording of track address data is avoided. The first groove has a configuration in which a region representing the track address of the first groove, the non-track address region, and a region representing the track address of the third groove adjacent to the first groove are formed in this order in the disc circumferential direction. The second groove has a configuration in which an area indicating a track address of an adjacent first groove, an area indicating a track address of the second groove, and the non-track address area are formed in the disk circumferential direction in this order. The third groove may include a track ad of the non-track address area and an adjacent second groove. This area represents the switch, and the area indicating the track address of the third groove has a configuration formed in this order on a disk in the circumferential direction.

Preferably, each non-track address area is provided with an additional wobbling portion representing data different from the track address.

Preferably, the information indicated by the additional wobbling portion is information common to grooves adjacent to each other.

Preferably, the further wobbled portions are formed in each of the grooves adjacent to the disc radial direction, and these pair of further wobbled portions face each other with lands therebetween and are also in phase.

Preferably, in the first to third grooves, instruction data indicating which track address is the data of the track address of the groove among the data of the track address read from the groove is recorded.

Preferably, the recording of the indication data is made by a pair of wobbling portions formed in the same phase on both sidewalls of the grooves.

Preferably, the instruction data is recorded at the head of one frame area including each of the first to third grooves.

Preferably, the plurality of grooves and lands comprise a plurality of segments partitioned by formation regions of a plurality of clock marks formed at regular intervals in the disc circumferential direction at least on the same track.

Preferably, the plurality of segments include a plurality of data segments including an address segment and a user use area, and an address data recording area by the wobble is formed in the plurality of address segments.

Preferably, a part where the address data recording area is not formed is formed in a part of the plurality of address segments, and this part is configured to be able to write data as part of the user use area.

Other features and advantages of the present invention will become more apparent from the following description of the embodiments of the invention.

1A is a plan view of an essential part, schematically showing an example of a pattern of a recording surface of an optical disc according to the present invention;

1B is an explanatory diagram showing an example of a signal obtained when the beam spot is irradiated to a land of the optical disk;

2 is a plan view of an essential part, schematically showing another example of the pattern of the recording surface of the optical disk according to the present invention;

3 is a plan view of an essential part, schematically showing another example of the pattern of the recording surface of the optical disc according to the present invention;

4 is a plan view of an essential part, schematically showing another example of the pattern of the recording surface of the optical disc according to the present invention;

5 is a plan view of an essential part, schematically showing another example of the pattern of the recording surface of the optical disk according to the present invention;

6A is an essential part plan view showing another example of a pattern of grooves and lands;

6B is an explanatory diagram showing an example of a signal obtained by the pattern shown in FIG. 6A.

7 is a plan view of an essential part showing an example of the prior art;

8 is an explanatory diagram of a band of a magneto-optical disk;

9 illustrates an arrangement of a plurality of frames.

10 is an explanatory diagram of a push pull method.

Best Mode for Carrying Out the Invention Preferred embodiments of the present invention will now be described in detail with reference to the drawings.

Fig. 1A shows the pattern of the recording surface of the magneto-optical disk to which the present invention is applied. The magneto-optical disk D of the present embodiment employs a so-called land groove recording method in which a plurality of grooves G and land L arranged in the radial direction (arrow Ra direction) are tracks for recording. Of course, unlike this embodiment, it is also possible to have a configuration in which only one of the grooves G and the land L is used as the track for recording.

The segments formed on the tracks of the grooves G include first to third address segments 10A to 10C and a plurality of data segments 11, which are arranged in the disc circumferential direction with the formation region of the fine clock mark 20 interposed therebetween. It is. The magneto-optical disk D of the present embodiment is characterized by a structure relating to the first to third address segments 10A to 10C, and other configurations are similar to those of the conventionally known magneto-optical disk. Therefore, the following description will focus on the structures of the first to third address segments 10A to 10C.

In this magneto-optical disk D, address data recording areas by so-called both wobbles are formed in the first to third address segments 10A to 1OC.

More specifically, in the Nth groove G, wobbling portions 31a and 31b are formed on both sidewalls of the first address segment 10A. These wobble parts 31a and 31b are in the same phase in which the wobble directions are arranged in the same manner, and the address data represented by each of the wobble parts 31a and 31b are the same. This address data is data modulated in a suitable manner. This address data includes a frame address, a band address, and a track address. The track address indicated by the wobbling portions 31a and 31b is N. This track address N is repeatedly recorded twice in one address segment 10A. Since the frame address and the band address are common data as long as they are tracks of the same frame and the same band, since errors in reading can be reduced, the track addresses are repeated twice to avoid error detection. The same holds true for other wobbling portions formed in the first to third address segments 10A to 10C.

Wobble parts 33a 'and 33b' are formed on both sidewalls of the third address segment 10C in the Nth groove G. As shown in FIG. These wobble parts 33a 'and 33b' are also wobbled in the same phase, and the track address indicated by them is an address (N-1) one address earlier than the Nth groove G in which they are formed.

In this way, in the Nth groove G, the wobbling portions 31a and 31b indicate the original track address of the groove G, while the wobbling portions 33a 'and 33b' indicate the track addresses of the adjacent groove G. It is. The second address segment 10B of the same groove G is an area in which address data is not recorded.

In the (N + 1) th groove G, wobbling portions 31a ', 31b', 32a, 32b are formed on both sidewalls of the first and second address segments 10A, 10B. The wobbling portions 31a 'and 31b' are wobbles of the same phase as the above-described wobbling portions 31a and 31b of the Nth groove G, and the track addresses indicated by them are N. FIG. The wobbling portions 32a and 32b are wobbled in the same phase with each other, and the track address indicated by them is (N + 1). The third address segment 10C of the same groove G is an area in which address data is not recorded.

In the (N + 2) th groove G, wobbling portions 32a ', 32b', 33a, 33b are formed on both sidewalls of the second and third address segments 10B, 10C. The wobbling portions 32a 'and 32b' are wobbled in the same phase as the wobbling portions 32a and 32b, and the track addresses indicated by them are (N + 1). The wobbling portions 33a and 33b are also wobbled in the same phase with each other, and the track address indicated by them is (N + 2). The first address segment 10A of the same groove G is an area in which address data is not recorded.

The address segments of the (N + 3) th and subsequent grooves G are basically the same as the address segments of the three grooves G of the Nth, (N + 1) th, and (N + 2) th described above. The configuration is repeated. That is, on both sidewalls of the first address segment 10A of the (N + 3) th groove G, wobble portions 31c and 31d of the same phase indicating that the address data is (N + 3) are formed. On both sidewalls of the third address segment 10C of the same groove G, the wobbling portions 33a 'and 33b' having the same phase as the wobbling portions 33a and 33b of the (N + 2) th groove G are formed. . On both sidewalls of the first address segment 10A of the (N + 4) th groove G, the wobbling portions 31c 'and 31d are in phase with the wobbling portions 31c and 31d indicating that the address data is (N + 3). ') Is formed, and wobbling portions 32c and 32d indicating that the address data is (N + 4) are formed on both sidewalls of the second address segment 10B of the same groove G.

Next, the operation of the magneto-optical disk D will be described.

First, in the case where the address data is read through the beam spot on the groove G, two track addresses are read. More specifically, for example, for the Nth groove G, the track address is read from the wobbling parts 31a and 31b, and the track address is from the wobbling parts 33a 'and 33b'. N-1) is read. For reading the address data of the groove G, the control circuit of the magneto-optical disk device is set so that the track address having the larger value is selected as the original track address of the groove G. As a result, for example, for the Nth groove G, the track address of N having the larger value among N and (N-1) is appropriately selected. Similarly, for the groove G other than the N-th, these track addresses can be appropriately read.

Further, for example, when the address data is read out by shining a beam spot on the first address segment 10A of the Nth groove G, the reflected light from the two wobbling portions 31a and 31b is obtained. Since these two wobbling portions 31a and 31b are wobbled in the same phase with each other, for example, the total wobble amount is doubled as compared with the case where only one of these two is formed. For this reason, the wobble detection signal (push-pull signal) detected by the push-pull method described with reference to FIG. 10 has an amplitude of about twice, and the wobble detection accuracy, that is, the accuracy of reading the address data is increased. In such a magneto-optical disk D, since both address segments indicated by the address data have a configuration in which two wobbling portions of the same phase are formed, the same operation as described above can be obtained even when the address of any groove G is read.

If the detection accuracy of the address data can be improved by the above principle, it is not necessary to increase the amount of light for servo in the optical detection system of the magneto-optical disk device. Therefore, it is also possible to increase the amount of light for detecting the magneto-optical signal for reading data from the data segment 11, thereby increasing the S / N of the magneto-optical signal. As described above, when a blue laser is used instead of a red laser as the laser light used for writing and reading data, the sensitivity of the photodetector tends to be lowered, but as described above, the magneto-optical disk of the present embodiment. Since D can increase the detection sensitivity of the address data, it is suitable for the next-generation magneto-optical disk device using a blue laser.

In manufacturing the magneto-optical disk D, it is necessary to form two wobbling portions on both sidewalls of one address segment, but since these two wobbling portions are in phase, they are formed by a method using one laser beam. can do. Therefore, it is also suitable for increasing the data recording density by making the track pitch small.

In this magneto-optical disk D, as described below, the address data for each land L can also be appropriately read.

When the beam spot Bs shown in FIG. 1A is moved along the land L in the direction of the arrow Na, the wobbling portions 31b ', 32b, 32a', and 33a formed in two grooves G between the lands L are disposed. Are read sequentially. In this case, since the wobbling parts 32b and 32a 'which properly indicate the track address of the land L are in phase and they are read out simultaneously, the detection signal has a large amplitude as indicated by the symbol Sb in Fig. 1B. . On the other hand, each of the wobbling portions 31b 'and 33a exists on only one side of the land L, and no wobbling portion is formed at the portion facing the land L with the land L therebetween. Therefore, these detection signals have a small amplitude of about half of the signal indicated by the symbol Sb, as indicated by the symbols Sa and Sc of FIG. 1B. From this, when processing the detection signals represented by these codes Sa to Sc, if signal detection processing is performed using threshold values for cutting the signals of the codes Sa and Sc, only the signal represented by the code Sb is appropriately extracted. Based on this, data of the track address of the land L can be appropriately read. In this magneto-optical disk D, a part sandwiched by two in-phase wobbling portions which properly indicate an address of the land L is formed in any of the plurality of lands L. As shown in FIG. Therefore, the address can be appropriately read for any land L.

2 to 5 show another example of the present invention. In these figures, the same or similar elements as in the above embodiment are given the same reference numerals as in the above embodiment.

The two address segments 10A and 10B shown in FIG. 2 are the first and second address segments 10A and 10B in the (N + 1) th and (N + 2) th grooves G shown in FIG. 1A. ). However, the wobbling portion is not formed at all in the first address segment 10A in the (N + 2) th groove G shown in FIG. 1A, but the address segment 10A (10A 'of the present embodiment corresponding to this) is not provided. The wobbling portions 310a 'and 310b' and the wobbling portions 311a 'and 311b' are formed on both sidewalls of the side wall).

The two wobbling portions 31a 'and 31b' of the first address segment 10A in the (N + 1) th groove G have a wobbling portion 310a indicating respective data of preamble, sink, frame address, and band address. , 310b). The wobbling parts 31a 'and 31b' also include wobble parts 311a and 311b indicating the preamble and resync again. Among the wobbling portions 31a 'and 31b', other portions than those described above are portions representing the data of the CRC for performing the track address and the data error check. The wobbling portions 310a 'and 310b' represent data having the same contents as the wobbling portions 310a and 310b, and are in the same phase as those of the wobbling portions 310a and 310b. The wobbling parts 311a 'and 311b' show data having the same contents as the wobbling parts 311a and 311b, and are in the same phase as those of the wobbling parts 311a and 311b.

According to this configuration, since the preamble or the like is also added to the first address segment 10A (10A ') in the (N + 2) th groove G, compared with the case of the embodiment shown in FIG. The leading position of becomes clearer. As described above, in the present invention, a configuration in which data other than the track address and the CRC is recorded for the address segment in which the track address does not need to be recorded. In the configuration shown in FIG. 1A, there are some wobbled parts in the second and third address segments 10B and 10C, but the common data other than the track address and the CRC is also displayed for these address segments. It goes without saying that a wobbling portion may be formed.

In the configuration shown in Fig. 3, only the first and second address segments 10A and 10B are formed in the address segment of the groove G. In such a configuration, no segment corresponding to the third address segment 10C of the embodiment shown in FIG. 1A is formed. The first address segment 10A is divided into a region near the left side s1 and a region near the right side s2 in FIG. 3, and N, (N + 1), and (N +) on both sides or one side of these two regions s1, s2. 2) or the wobbling portion 30 of the address data including the track address such as (N + 3) is appropriately formed. In contrast, in the second address segment 10B, only the area s3 near the left side of FIG. 3 becomes an area representing address data, and the wobbling portion 30 is appropriately formed. In addition, each wobbling unit 30 does not repeat the same track address twice, but only once. In this respect, the wobbling unit 30 has a configuration different from that of the embodiment shown in Fig. 1A.

In the case of reading data by irradiating a laser beam onto the magneto-optical disk, the laser beam is irradiated onto the transparent substrate of the magneto-optical disk to reach the recording surface with the light transmitted through the transparent substrate, There is a method of irradiating a laser beam to the recording surface from the transparent protective film side having a small thickness. According to the so-called double wobble system of the present invention, the influence of the tilt is less likely to be affected by the tilt than the so-called wobble system of the prior art. However, when the latter method is employed, the influence of the tilt of the magneto-optical disk during data reading is further affected. It becomes possible to make it hard to receive. Therefore, even if the track address is not stored twice, it is possible to read the track address appropriately. The configuration shown in Fig. 3 is suitable for the case of employing such a scheme.

In the embodiment shown in Fig. 3, the same track address is not repeated twice on one track, and the address segment is composed of only the first and second address segments 10A and 10B so that the total number thereof is small. The data area can be reduced. For this reason, the user data area can be enlarged. In particular, the area s4 near the right side of the second address segment 10B can be used as the magnetic recording data area similarly to the data segment 11. Therefore, it is suitable for increasing the format efficiency and increasing the data storage capacity.

In FIG. 3, for example, the region s2 near the right side of the first address segment 10A indicated by the reference numeral n1 and the region s3 near the left side of the second address segment 10B indicated by the reference numeral n2 have a configuration in which no wobbling portion is formed. It is. In the present invention, similarly to the contents described with reference to FIG. 2, a wobbling portion indicating a preamble or other data can be formed in such a portion. More specifically, as shown in FIG. 4, for example, the wobbling portions 300a 'and 300b' correspond to the address segments 10A and 10B indicated by the reference numerals n1 'and n2', respectively. Is formed. The wobbling portion 300a 'has the same phase as the wobbling portion 300a indicating the data of the preamble and resync again included in the wobbling portion 30 of the adjacent address segment 10A indicated by the reference numeral n3. In addition, the wobbling unit 300b 'is a wobbling unit 300b indicating data of preamble, sink, frame address, and band address included in the wobbling unit 30 of the adjacent address segment 10B indicated by the code n4. It is in phase with. Even in such a configuration, as in the case shown in Fig. 2, it is easy to recognize the head of the frame when reading data.

In the configuration shown in FIG. 5, the wobbling portions 30 are formed in a constant arrangement in the area s6 near the right side of the first address segment 10A and the area s7, s8 near the left and right sides of the second address segment 10B. have. These wobble parts 30 have the same phase relationship as opposed to each other as in the previous embodiment. A pattern in a plan view as shown in Fig. 6A is formed in the area s5 (head region) near the left side of the first address segment 10A. According to the pattern shown in Fig. 6A, each of the lands L (N), L (N + 1), and L (N + 2) in the N, (N + 1), and (N + 2) th beam spots is formed. The push-pull signal obtained by passing becomes a waveform as shown to (a)-(c) of FIG. 6B. This is because, in the portion shown in Fig. 6A, the amplitude of the push-pull signal is larger than the other portion in the wobbled phase. Here, in the push-pull signals shown in Figs. 6B (a) to (c), when a portion having a large amplitude is set to "1" and a small portion is set to "0", in land L (N), (1, A signal of 0) obtains a signal of (0, 1) in the land L (N + 1), and a signal of (0, 0) in the land L (N + 2). By these signals, three types of lands L (N), L (N + 1), and L (N + 2) can be distinguished. Therefore, based on such data, it is possible to determine which address is to be adopted among the track addresses read from the land L. FIG.

Specifically, in the configuration shown in Fig. 5, three track addresses of N, (N + 1) and (N-1) are read in this order when passing the beam spot through the portion of the land L (N). When the signal is detected, it is determined in advance that the track address to be read first is adopted. In this way, the addresses of (N + 1) and (N-1) read second and third times will not be adopted incorrectly. Similarly, based on the signal, it is possible to adopt an address read second for land L (N + 1) and an address read third for land L (N + 2). As described above, since the amplitude of the push-pull signal is small in the portion where the wobbling portion is formed only on one side of the land L, it is prevented from being mistakenly detected as an appropriate track address, but in addition to the above-described method, It is possible to more reliably prevent the possibility of falsely detecting the track address.

This invention is not limited to the content of the above-mentioned embodiment. The specific structure of each part of the optical disk according to the present invention can be modified in various designs.

In the present invention, the specific number of address segments formed in one track or frame is not limited to two or three. For example, there is only one address segment, and a wobbling portion indicating a plurality of types of track addresses such as N, (N + 1), or (N + 2) is arranged in the circumferential direction of the disc. It may be formed so as to.

The optical disk according to the present invention is not limited to the magneto-optical disk, as can be understood from the definition at the outset. The present invention can be applied to various optical disks as long as wobble is used for recording address data.

Claims (14)

delete delete delete A plurality of grooves and a plurality of lands are alternately formed in the disk radial direction, and the plurality of grooves are provided with an address data recording area formed by wobble. The address data recording area has a configuration in which a pair of wobbling portions of the same phase are formed on both sidewalls of the groove, The grooves have a configuration in which a pair of wobbling portions of the same phase are formed in each groove adjacent to the disk radial direction, Each of the lands is sandwiched by grooves adjacent to the disk radial direction and provided with a pair of wobbling portions of the same phase as the wobbling portion of the groove adjacent to the disk radial direction. The address data recording area formed in the plurality of grooves includes a first recording area indicating individual addresses of the grooves, and a second recording area indicating addresses of other grooves adjacent to the grooves, The grooves have a configuration in which a first recording area of one groove and a second recording area of another groove adjacent thereto face each other with the land interposed therebetween, and these wobbling portions have the same phase. , The first and second recording areas of the plurality of grooves are formed in an arrangement shifted in the disc circumferential direction between grooves adjacent to the disc radial direction, The portions of the first and second recording regions facing each other with the land interposed therebetween are configured not to be adjacent to each other in the disc radial direction. The method of claim 4, wherein The grooves have a structure in which the first to third grooves are arranged repeatedly in the radial direction of the disc and have a non-track address area in which recording of track address data is avoided. In the first groove, an area indicating the track address of the first groove, the non-track address area, and an area indicating the track address of the third groove adjacent to the first groove are formed in this order in the disc circumferential direction. Have a configuration, The second groove has a configuration in which an area indicating a track address of an adjacent first groove, an area indicating a track address of the second groove, and the non-track address area are formed in this order in the disc circumferential direction, The third groove is a light in which the non-track address area, the area indicating the track address of the adjacent second groove, and the area indicating the track address of the third groove are formed in this order in the disc circumferential direction. disk. delete delete delete delete delete delete delete delete delete

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