JPH11126376A - High-density optical disk and optical disk reproducing device and manufacture of master optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk efficiently recorded with address information attached to sectors of the optical disk of a narrow track pitch. SOLUTION: At least one region of the optical disk 100 having at least one region along a radiation direction and having plural tracks within at least one regions includes the address regions arranged radially on the plural tracks. The data common between the tracks adjacent to each other among the plural tracks is recorded in the same radial positions on the adjacent tracks and the data different between the adjacent tracks is recorded in the radial different positions on the adjacent tracks.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk for reproducing and recording data by using a laser beam, an optical disk apparatus for reading and recording a signal using the optical disk, and a method for manufacturing an optical disk master.

[0002]

2. Description of the Related Art In recent years, optical disks have been put to practical use as media for storing large-capacity data files such as music and videos, and the capacity has been increased for more applications.

At present, the recording density of an optical disk device is 0.4
up to about μm / bit, 1.2μm in track direction
To the extent.

Various methods have been proposed to achieve higher densities. One of them is a disk super-resolution system in which a reproduction film of an optical disk has a super-resolution reproduction function (Japanese Patent Laid-Open No. 4-271039, US Pat. No. 5,168,482). The super-resolution playback function uses a playback film that has the function of generating a playback signal in a certain temperature range of the playback film heated by the light beam focused on the optical disk medium. It reproduces a high-resolution image having a resolution higher than that of the above. According to the disk super-resolution method, it is possible to reproduce a signal with a resolution higher than the resolution of the light beam determined by the wavelength of the light source and the aperture of the condenser lens. Therefore, a high-density optical disk device can be realized. Specifically, according to the disk super-resolution method, the recording density can be increased to about 0.2 μm / bit in the linear density direction and to about 0.6 μm in the track direction.

In realizing an optical disk by the disk super-resolution method, it is necessary to preformat addresses (sectors and track numbers recorded in a sector identification area) by providing irregularities on the disk. However, since the uneven recording mark has no super-resolution effect, if an address is recorded at a narrow track pitch of about 0.6 μm, an error occurs due to crosstalk from an adjacent track, and the address cannot be reproduced. In order to avoid this problem, an optical disk recorded so that the address position is not adjacent between adjacent tracks (Japanese Patent Laid-Open No. 6-894
No. 73 (US Pat. No. 5,422,874).

[0006] Such an optical disk in which addresses are recorded in advance with irregularities is manufactured by manufacturing a master and duplicating the master by injection or the like.

This master is usually manufactured through the following steps. A photoresist film is formed on a circular glass substrate, and a light beam such as an argon laser or a krypton laser is focused on the photoresist film while rotating the glass substrate precisely. Portions (grooves and uneven pits) of the photoresist film exposed by the condensed light are exposed. Thereafter, the photoresist film is developed to obtain a photoresist film having a predetermined pattern (grooves and uneven pits). Using the obtained photoresist film as a mask, the glass substrate is etched to form grooves and irregularities on the surface of the glass substrate. After the resist is removed and the surface of the glass substrate is made conductive, the glass substrate that has been made conductive is finally subjected to electrodeposition of nickel or the like, thereby producing a master disk of the optical disk.

In recent years, an electron beam has been used instead of a light beam when producing a high-density master.

[0009]

The optical disk disclosed in JP-A-6-89473 (US Pat. No. 5,422,874) has a radial address area between adjacent tracks in order to realize a narrow track pitch. They are located in different locations. For this reason, the address area needs to be twice as long as the data length of the address area actually used, which sacrifices the capacity of the optical disk.

JP-A-6-89473 (US Pat. No. 5,42
No. 2,874), an optical disk having a data recording portion formed by grooves or between grooves, such as the optical disk disclosed in
It was very difficult to make the master. That is,
The concavo-convex portion of the address area needs to have a width of 0.3 to 0.4 μm in order to improve its reproduction characteristics. On the other hand, the groove, which is a data recording portion, has a groove width of about 0.6 to 0.7 μm, which is about the track pitch, in order to maintain the reproduction characteristics between the groove and the groove.
Need to be However, in the conventional optical disk master method, since the master is usually manufactured using one light beam or electron beam, the line width that can be exposed is constant, and the width can be largely changed between the address portion and the groove portion. It was very difficult.

Here, a method of using two light beams having different spot diameters of the light beam in order to change the width of the address portion and the groove portion is also known. However, when a master is manufactured using these two light beams, two
It was necessary to align the light beams of the book with an accuracy of 0.1 μm or less, and it was very difficult to manufacture a master. Furthermore, the width of the groove on the manufactured master is 1.
It could only be increased up to about five times.

[0012]

The optical disk of the present invention comprises:
Dividing concentrically into one or more regions, having a plurality of tracks in the region, the plurality of tracks being further divided into a plurality of regions along a radiation direction, and being radially arranged along the tracks Address has an address area formed on the track, and the data arrangement of this address area is such that data common to adjacent tracks differs in the same radial position between adjacent tracks and between adjacent tracks. An optical disc composed of a first track and a second track in which data is recorded at different radial positions between adjacent tracks, thereby solving the above-mentioned problem.

[0013] The data portion of the first track may be formed by a groove, and the second track data recording portion may be formed by a groove.

The optical disc reproducing apparatus of the present invention for reproducing an optical disc in which the polarity of a signal for guiding the first and second tracks is inverted between the first track and the second track is provided. And an arrangement detector for detecting position information of the address data of the address area associated with the second track and the second track, and a determiner for determining the polarity of a signal for tracking and guiding from the arrangement detector. An optical disk device characterized by the above feature, whereby the above problem is solved.

The optical disk device has an address error detector corresponding to the first and second tracks, and the optical disk device transmits information of the error detection of the address to a data portion of the first track and the second track. May be used as information for determining the tracking polarity.

An optical disk according to the present invention has at least one area along a radiation direction, and
An optical disc having a plurality of tracks in one area, wherein the at least one area includes an address area radially arranged on the plurality of tracks, and in the address area, Data common to tracks adjacent to each other is recorded at the same radial position on the adjacent track, and different data between adjacent tracks corresponds to different radial patterns on the adjacent track. The optical disk is recorded at a position where the optical disk is positioned, thereby achieving the above object.

The plurality of tracks include a plurality of first tracks and a plurality of second tracks, and the plurality of first tracks
Each of the plurality of tracks and each of the plurality of second tracks are alternately repeated, and the address area includes data common to the plurality of first tracks and the plurality of second tracks. The data at the same radial position, the plurality of first tracks and the plurality of second tracks.
And different data between different tracks, and data at different radial positions.

The at least one area further has a data recording area different from the address area. In the data recording area, the first track is formed by a groove, and the second track is formed by the groove. The first track may be formed between the grooves.

In the address area arranged on the second track, the first track of the address area where different data is recorded between the first track and the second track is , A groove.

A reproducing apparatus according to the present invention has at least one area along a radiation direction, and reproduces data recorded on an optical disk having a plurality of tracks in the at least one area, In the optical disc, the at least one area includes an address area radially arranged on the plurality of tracks, and in the address area, the address area is common to tracks adjacent to each other among the plurality of tracks. Data is recorded at the same radial position on the adjacent track, and different data between the adjacent tracks is recorded at different radial positions on the adjacent track. The polarity of tracking changes at least partially between the adjacent tracks, and A detecting unit for detecting a recording position of data recorded in the data area, and a determining unit for determining a tracking polarity of a track being reproduced among the plurality of tracks based on an output from the detecting unit. A playback device, which achieves the above object.

The detection section is an error detection section for detecting error information of data recorded in an address area corresponding to each of the adjacent tracks, and the recording position of the data is determined by the error information of the data. It may be detected based on the detection.

According to the present invention, there is provided a method of manufacturing a master of an optical disk, comprising: (a) providing a substrate having a photoresist film formed on a surface thereof; and (b) rotating the substrate relative to a beam. (C) irradiating the photoresist film on the substrate with the beam;
Forming a first trajectory on the photoresist film; and (d) forming a second trajectory on the photoresist film by further irradiating the beam so as to partially overlap the first trajectory. And (e) fabricating a master of an optical disc using the photoresist film, thereby achieving the object described above.

In the step (d) of the method for producing a master of the optical disk, the second trajectory may be formed by irradiating the beam with the beam deflected in a radial direction of the substrate.

[0024] The step (d) of the method for producing a master of the optical disk may include forming a second trajectory larger than a half width of the beam in a photoresist film.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the embodiments, the same components are denoted by the same reference numerals.

(Embodiment 1) FIG. 1A shows the configuration of an optical disc 100 according to Embodiment 1 of the present invention.

The optical disc 100 includes a first zone 101 and a second zone 102 obtained by dividing the optical disc 100 by concentric circles, a sector 103 obtained by dividing the first zone 101 into 12 along the radiation direction, and a second zone 102. Is divided into 16 along the radiation direction, an address number area 105-1 of the sector 104 recorded by uneven pits, and a data recording area 106 for recording data of the sector 104.

The optical disk 100 is not limited to being divided into the first and second zones 101 and 102, but may be divided into three or more zones.

First and second zones 101 and 10
No. 2 is divided into sectors so that the linear density of the tracks on the disk 100 is substantially constant. In the embodiment described in the present invention, the first zone 101 includes 12 sectors 103 and the second zone 102 includes 16 sectors. However, the condition for division is not limited to this, and the division may be made according to other appropriate conditions.

In this embodiment and each of the following embodiments, only the outer sector is referred to in describing the invention. However, the present invention can be applied to the inner sector 103 in the same manner.

FIG. 1B shows an address number area 105-.
1 and the configuration of the data recording area 106.

The address number area 105-1 includes an address mark area 107 in which an address mark for identifying the start of an address number is recorded, a sector number area 108 in which a sector number indicating a sector number is recorded,
A first track number area 109 in which a track number of a groove (groove) track 111 is recorded, and a second track number area 110 in which a track number of a land (land) track 112 sandwiched between the grooves 111 is recorded. including.

In the optical disc 100 according to the first embodiment,
The address mark and the sector number of the same sector are recorded at the same position in the radial direction of the optical disc 100 between adjacent tracks, that is, the address mark is recorded in the address mark area 107, and the sector number is recorded in the sector number area. Data recorded in the address mark area 107 and the sector number area 108 is assigned a common value in adjacent tracks.

Track numbers that can take different values between adjacent tracks are divided into track numbers during groove tracking and track numbers during land tracking, and the first and second tracks are not adjacent to each other between adjacent tracks. 2 track number areas 109 and 1
Recorded at 10.

The data recording area 106 includes a spiral groove (groove) track 111 for tracking guide and an inter-land (land) track 112 sandwiched between the grooves 111. The recording data is recorded on the groove track 111 and the land track 112.

In the present embodiment, the width of the groove 111 is set to 0.7 μm.
m, the width of land (land) between the grooves 111 is 0.7 μm
It is. Even with such a very narrow track pitch, in the data recording area 106, crosstalk from adjacent tracks is greatly reduced by the disk super-resolution method. Therefore, data can be read and written at a low error rate.

In the sector number area 108 and the track number areas 109 and 110 of the address number area 105-1, the data is bi-phase modulated in which "1" is represented by "10" and "0" is represented by "01". Has been recorded. In the address mark area 107, a code 111000 that does not appear in biphase modulation is recorded as an address mark.

Since the data in the address number area 105-1 is recorded using the unevenness of the disk, the super-resolution effect of the disk cannot be obtained. Furthermore, crosstalk may occur, and the data recorded in the address mark area 107 and the sector number area 108 may not be reproduced.

However, according to the above-described data arrangement, even if crosstalk occurs as a result of not being able to obtain the super-resolution effect, reproduction of the address marks and sector numbers recorded in the address mark area 107 and the sector number area 108 is performed. Is possible. This is because the signal that interferes with the crosstalk is the same as the signal of the track to be read, and is not affected by the crosstalk. Therefore,
No reading error occurs due to crosstalk.

Further, the address mark and the sector number are stored in the groove track 111 or the land track 1.
Regardless of whether the data is 12 data, they are recorded on the optical disc 100 adjacent to each other. Therefore, the data length of the address number area 105-1 is shortened by the length of the data area of the address mark area 107 and the sector number area 108 as compared with the case where all the address information for each track are recorded so as not to be adjacent to each other. can do. That is, the capacity of the optical disk can be used effectively.

The track numbers of tracks adjacent to each other recorded in the track number areas 109 and 110 are determined so as not to be adjacent to each other on the optical disc 100 according to the track number of the groove track 111 or the track number of the land track 112. Are alternately recorded in the track number areas 109 and 110. Therefore,
The track pitch of the track on which the track number is recorded is doubled, and crosstalk from a neighboring track is greatly reduced.

In the above description, the address mark and the sector number can take a common value between adjacent tracks, but the types of data that can take a common value are not limited to these. Even for data other than address marks and sector numbers, the optical disk of the present invention separates and records data that is common and non-common between adjacent tracks, thereby making it more efficient and having a much lower error rate than before. Can constitute the address number area 105-1.

In the above description, the track number recorded in the first track number area 109 represents the track number of the groove track 111, and the track number recorded in the second track number area 110 is the land track. It is assumed that the track number 112 is indicated. However, the first track number area 109 is the track number of the land track, and the second track number area 110 is the groove.
It may represent a track number.

In the embodiment described below,
The order of the area where the track number of the groove (groove) track is recorded and the area where the track number of the land track is recorded are not limited to the illustrated example.

(Embodiment 2) In Embodiment 1, the second
When the track number area 110 is tracked, the address pits in the second track number area 110 (FIG. 1B) behave like partial grooves, despite tracking the land. As a result, a large disturbance is added to the tracking error signal.

In order to avoid off-tracking due to this disturbance, it was necessary to hold the tracking servo when reading the second track number portion in the optical disc of the first embodiment.

The optical disk according to the second embodiment of the present invention has a track number area 110 (FIG. 1) for land tracking included in the address number area 105 (FIG. 1B).
Except for the configuration of (b)), the configuration is the same as that of the optical disc described in the first embodiment. Therefore, description of the configuration other than the configuration of the track number area is omitted.

FIG. 2 shows the configuration of the address number area 105-2 of the optical disk in the present embodiment.

The track number area 114 indicating the track number of the land track 112 includes a plurality of pits indicating the land track number on the land track. Further, a groove 116 is formed on a track in the track number area 114 where a plurality of pits are not formed.

Normally, in an optical disk, land tracking is performed by using the edge of an adjacent groove. Therefore, providing the groove 116 enables stable tracking of the land. That is, disturbance during tracking can be greatly reduced. As a result, the tracking hold required when reproducing the optical disc of the first embodiment becomes unnecessary. By providing the groove 116, tracking can be performed stably even when the groove track 116 in the first track number area 109 and the data recording area is reproduced.

(Embodiment 3) FIG. 3A shows the configuration of an optical disc 200 according to Embodiment 3 of the present invention.

The optical disc 200 includes a first zone 201 and a second zone 202 obtained by dividing the optical disc 200 into concentric circles, a sector 203 obtained by dividing the first zone 201 into twelve along the radiation direction, and a second zone 201. 202
204 divided into 16 sectors along the radiation direction, an address number area 205 of the sector 204 recorded by uneven pits, a data recording area 206 for recording data of the sector 204, and tracking of lands and grooves. The address number area 207 where the switching occurs, the track number of the groove track in the address number area 205 or 207 and the CRC (Cyclic
Redundancy Check) A groove address area 208 in which an error code is recorded, a track number of a land track in the address number area 205 or 207, and a CRC.
And a land address area 209 in which an error code is recorded. The CRC error code is information used to detect an error that occurs when reading information recorded on an optical disc.

The optical disk 200 is not limited to being divided into the first and second zones 201 and 202, but may be divided into three or more zones.

First and second zones 201 and 20
2 is divided into sectors so that the linear density of tracks on the disk 200 is constant. However, the condition for division is not limited to this, and the division may be made according to other appropriate conditions.

The optical disc 100 of the first embodiment (FIG. 1)
In this case, since the groove of the data recording portion is spiral, the groove and the land are not connected. Therefore, the Nth
In order to continuously reproduce the groove portion of the track and the land portion of the (N + 1) th track, it is necessary to move the reproduction light spot from the groove portion to the land portion, that is, to jump the track.

The optical disk 200 according to the present embodiment has the structure shown in FIG.
As shown in (1), the groove portion is switched to a land portion at a part of the circumference of the disk. This optical disk 20
According to the structure of 0, continuous reproduction between the groove portion and the land portion of the track can be realized without jumping the track. For example, when the reproduction of the groove portion of the N-th track is completed, the reproduction can be automatically shifted to the reproduction of the land portion of the (N + 1) -th track without a track jump.

Referring to FIG. 3B and FIG. 3C,
The data arrangement of the optical disc 200 having the structure shown in FIG. 4 will be described.

FIG. 3B shows an address number area 207 of the sector 204 where the groove and the land are switched.

The address number area 207 includes an address mark area, a sector number area, a groove address area 208, and a land address area 209. The address mark area and the sector number area are recorded at the same position in the radial direction of the optical disc 200 between adjacent tracks, similarly to the arrangement of the address mark area and the sector number area described in the first embodiment.

The groove address area 208 and the land address area 209 include a track number and a CRC error code. Since the track number and the CRC error code can take different values between adjacent tracks, the groove address area 208 and the land address area 209
Are arranged on the optical disc 200 such that adjacent tracks are not adjacent to each other. As described in the first embodiment, this arrangement can avoid crosstalk.

These address data are stored in the groove address area 208 before the data recording area 206 of the groove track, and in the data recording area 206 of the land track.
Are recorded in the land address area 204 respectively. That is, for a groove track in the data recording area 206 following the address number area 207, the track number and the CRC error code are recorded in the groove address area 208 of the address number area 207. At this time, the land address area 209 is blank. For a land track in the data recording area 206 following the address number area 207, a track number and a CRC error code are recorded in a land address area 209 in the address number area 207. At this time, the groove address area 208 is blank.

The address number area 205 shown in FIG. 3C is an address number area of the sector 204 in which the groove and the land are not switched. Similarly to the address data included in the address number area 205, the address data of the groove track 206 is recorded in the groove address area 208, and the address data of the land track 206 is recorded in the land address area 209.

Hereinafter, the case where the groove portion is switched to the land portion or the position where the land portion is switched to the groove portion on the optical disc 200 of the present embodiment will be described.

The continuous reproduction between the groove portion and the land portion without the track jump means that the tracking polarity (position) changes from the land to the groove or from the groove to the land with the address number area 207 as a boundary. I do. This change in tracking polarity (position) can occur in one or more adjacent tracks. If it is detected that the tracking polarity (position) changes, it is possible to specify whether the data recording area 206 after the address number area 207 is a groove or a land.

The recording position of the track number and CRC error code is determined according to the tracking position of the data recording area following the address number area 207.

By recording the optical disk track number and the CRC error code in the address number area 207 as described above, the tracking position of the data recording area 206 can be determined from the error information read from the address number area 207.

Hereinafter, a method for determining the tracking position will be described with reference to FIG.

FIG. 5 is a block diagram showing the configuration of the tracking position determiner 350 of the apparatus for reproducing an optical disk in this embodiment. Tracking position determiner 350
Is included in a reproducing apparatus for reproducing an optical disk.

The tracking position determiner 350 is an address demodulator 301 for demodulating the groove address area 208 and the land address area 209 shown in FIG.
And 302, and error determiners 303 and 30 for performing a CRC error determination of the address demodulators 301 and 302.
4 and AND gates 305 to 307.

Address demodulators 301 and 302 demodulate the read address data. Error determiner 3
03 and 304 output 1 when an address demodulation error has not occurred, and output 0 when an address demodulation error has occurred. Error determiners 303 and 304
Makes an error determination using the CRC error code as described above. This determination is for determining whether or not the CRC error code is recorded in the area of the track currently being reproduced and in which area of the track the CRC error code is recorded. Therefore, the error determiner 303
And 304 are used to detect the recording position of the CRC error code. AND gates 305 to 307
A determination result is received from the error determiners 303 and 304, and a signal indicating whether the read address data is address data for performing groove tracking, address data for performing land tracking, or a reproduction error is output. Based on this output, a tracking position determining unit (not shown) of the optical disk reproducing device determines the tracking polarity (position) of the track being reproduced.

The case where the N-th and (N + 1) -th tracks of the address number area 205 (FIG. 3C) are reproduced using the address demodulators 301 and 302 will be described.

In the N-th track of the address number area 205 (FIG. 3C), the groove address area 208
A track number and a CRC error code are recorded in FIG. In this case, the output of the error determiner 303 becomes 1, the output of the error determiner 304 becomes 0, and AND
The gate 305 outputs a signal indicating groove tracking. As a result, the playback device that has been playing back the groove portion determines that the subsequent playback position is still a groove portion based on the signal indicating the groove tracking output from the tracking position determination device 350.

In the (N + 1) th track of the address number area 205 (FIG. 3C), a track number and a CRC error code are recorded in the land address area 209 (FIG. 3C). In this case, the output of the error determiner 303 is 0
Then, the output of the error determiner 304 becomes 1, and the AND gate 306 outputs a signal indicating land tracking. As a result, the playback device that was playing back the land
Based on the signal indicating the land tracking output from the tracking position determiner 350, the subsequent reproduction position is still determined to be a land portion.

If the address section 205 has a defect and both of the error determiners 303 and 304 have an error,
The output of the AND gate 307 becomes 1, and a signal indicating an address reproduction error is output. In the case of an address playback error, the playback device determines the tracking position using the previously played sector number and the sector number of the current tracking position zone, and determines whether the subsequent playback position is a groove portion or a land portion. I do.

Next, the address demodulators 301 and 3
The case where the N-th and (N + 1) -th tracks of the address number area 207 (FIG. 3B) are reproduced using 02 will be described.

The address number area 207 (FIG. 3)
The (N) th track in (b)) is the address number area 2
Before and after 07 (FIG. 3B), the groove track is switched to the land track.

Address number area 207 area (FIG. 3)
In the N-th track of (b)), a track number and a CRC error code are recorded in the land address area 209 (FIG. 3B). In this case, the error determiner 30
The output of 3 becomes 0, the output of error determiner 304 becomes 1, and a signal indicating land tracking is output by AND gate 306. As a result, the playback device that has been playing back the groove portion determines that the subsequent playback position is the land portion based on the signal indicating the land tracking output from the tracking position determination device 350.

Address number area 207 (FIG. 3)
In the (N + 1) th track of (b)), the track number and the CRC are stored in the groove address area 208 (FIG. 3B).
Error code is recorded. In this case, the output of the error determiner 303 is 1 and the output of the error determiner 304 is 0.
And a signal indicating groove tracking is output by the AND gate 305. As a result, the reproducing apparatus reproducing the land portion determines that the subsequent reproducing position is the groove portion based on the signal indicating the groove tracking output from the tracking position determining device 350.

As described above, by changing the format of the address recording area depending on whether the next position to be reproduced is a groove or a land, the groove is moved from the groove to the land or from the land to the land. Even if the tracking position changes to the groove portion, the tracking position to be reproduced next can be easily detected.

(Embodiment 4) In this embodiment, a method for producing a master of an optical disk described in Embodiments 1 to 3 of the present invention will be described. The optical disc 100 of the present invention (FIG. 1)
(A)) Address number area 105-1 (FIG. 1 (b))
It is most desirable from the viewpoint of reproduction characteristics that the pit width of the concave and convex portions is approximately 0.3 to 0.4 μm, and the groove width of the tracking guide groove of the data recording portion is 0.7 μm, which is the same as the track pitch. Hereinafter, a method of manufacturing a master of the optical disc 400 of the present invention having the above pit width and groove width will be described with reference to FIGS. 6 (a), 6 (b) and 6 (c).

FIG. 6A shows an optical disk master 400 manufactured by the optical disk master manufacturing method of the present embodiment.
Is shown.

The optical disc master 400 has a groove section 401 as a data recording area, a common data section 402 of an address including an address mark and a sector number, and a first non-common data section 403 including a track number of a groove.
And a second non-common data portion 404 including a track number of a land, and a groove deformed portion 406 in which a part of the groove is deformed.
And a land portion 405 that is a data recording area. Each groove portion 401 and each land portion 405 are track 4
07.

Referring to FIGS. 6B and 6C, FIG.
A method for producing a master having the pattern (a) will be described.
In FIGS. 6B and 6C, it is assumed that the master is manufactured from the left to the right in the figure and the tracks in FIG. 6A are manufactured from the top to the bottom of the figure.

For the sake of simplicity, the present embodiment will be described starting from a state in which a photoresist film is formed on a circular glass substrate. As a method of forming a photoresist film on a circular glass substrate, a known method may be used. The term "cutting" used below refers to forming a mark portion or a groove portion on a photoresist film formed on a circular glass substrate when a master of an optical disk is manufactured.

FIG. 6B shows a state where the substrate is cut by a light beam in the first rotation. The cut portions are indicated by halftone dots. The groove 401 is partially cut by irradiating the light beam with the light beam displaced from the center line of the track 407 by p.

Next, the displacement P of the light beam is set to zero, and the common data section 402 and the first non-common data section 403 are cut.

Then, the light beam is irradiated again with the light beam displaced by P from the center line of the track 407 to cut the groove 401. The cutting of the groove deforming portion 406 can be realized by increasing the displacement amount P of the irradiation position of the light beam.

By changing the displacement amount P by the first rotation of the substrate as described above, a part of the bit and the groove is cut.

FIG. 6C shows a state where the substrate is cut by a light beam in the second rotation of the substrate. The cut part is painted black. In the second rotation of the substrate, the groove portion 401 partially cut by the first rotation of the substrate is further cut.

In the second rotation of the substrate, the light beam irradiation position is shifted from the center line of the track next to the track cut by the first rotation of the substrate by the displacement amount Q in the direction of the groove 401 where cutting is desired. ing. At this time, the groove portion 401 is cut so as to partially overlap the cutting portion at the time of the first rotation of the substrate.

Next, the displacement Q of the light beam is set to zero, and the common data section 402 and the second non-common data section 404 are cut. The cutting of the groove deforming portion 406
This can be realized by setting the above-described displacement amount Q smaller. Also in this case, the groove deforming portion 406 is cut so as to partially overlap the light beam locus at the time of the first rotation of the substrate.

When the cutting is completed, a master optical disc can be manufactured using the photoresist film on which the light beam locus is formed. The steps up to the final production of the master are the same as those of the conventionally known method, and a description thereof will be omitted.

According to the above-described cutting method, one light beam or electron beam is deflected (shifted) in the radial direction at an arbitrary position on the substrate, and the light at the time of the first rotation and the light of the second rotation are rotated. By partially overlapping the beam trajectory, a mark portion or groove portion 401 having an arbitrary position and an arbitrary shape can be cut.

For example, a mark portion (common data portion 402 and non-common data portion 4) larger than the half width of the light beam
03, 404) or a desired portion of the groove portion 401 can be cut to produce a master optical disc.

For example, it is possible to easily produce an original master of an optical disk having different widths in the address uneven portion and the groove portion.

It is difficult to form groove deformed portions 406 having different groove widths in a part of the groove 401 even by using a conventional master manufacturing apparatus using two light beams. However, according to the method of manufacturing an optical disk master described in the present embodiment, the groove deforming portion 406 can be easily manufactured only by changing the traveling position of the light beam. This is because it is relatively easy to control the traveling position of one light beam at 0.1 μm or less. By using the above method, it is not necessary to use an expensive master manufacturing apparatus having two beams.

In this embodiment, the case where the cutting is performed without changing the intensity of the light beam has been described. However, the width of the mark portion and the groove portion 401 can be more flexibly changed by changing the intensity of the light beam as needed. More specifically, the width of the groove can be increased to about three times the width of the mark.

In the above description, the light beam is applied to the rotating glass substrate. However, this is one example in which cutting is performed by the relative movement of the light beam and the glass substrate, and is not limited to the case where the glass substrate rotates. For example, the irradiation may be performed while the light beam is rotated while the glass substrate is fixed.

In the above description, the light beam is applied to the rotating glass substrate. However, it is not limited to a light beam as long as the photoresist film can be exposed, such as an electron beam.

[0100]

According to the optical disc of the present invention, data common to adjacent tracks among a plurality of tracks is recorded at the same radial position on adjacent tracks, and different data is recorded between adjacent tracks. Are recorded at different radial positions on adjacent tracks. Thereby, the recording density efficiency is improved. Further, an error due to crosstalk can be avoided, and a high-density disk having an address area with high efficiency and a low error rate can be realized.

According to the present invention, the tracking position of the track being reproduced can be detected based on the predetermined information recorded on the track. Therefore, according to the present invention, when reproducing an optical disk having a structure in which the groove part is switched to the land part in a part of the circumference of the disk,
Even if the tracking polarity (position) changes from the groove portion to the land portion or from the land portion to the groove portion, the tracking position to be reproduced next can be easily detected.

According to the method of manufacturing a master of an optical disk of the present invention, the groove of the master of the optical disk is manufactured by performing the substrate rotation process twice, so that a light beam of one width can be used to form the address unevenness and the width of the groove. Can be easily produced.

According to the method for producing a master of an optical disk of the present invention, the groove deformed portion can be easily produced only by changing the traveling position of the light beam.

According to the method for producing an optical disk master of the present invention, sagging of the slope of the groove can be reduced and the width range can be varied as compared with the method of forming a wide groove by only controlling the power of one beam. It is.

[Brief description of the drawings]

FIG. 1 is an optical disc 10 according to a first embodiment of the present invention.
FIG. 3 is a diagram showing a configuration of 0 and its address number area 105-1.

FIG. 2 is a diagram showing a configuration of an address number area 105-2 of an optical disc according to Embodiment 2 of the present invention.

FIG. 3 is an optical disc 20 according to a third embodiment of the present invention.
FIG. 3 is a diagram showing a configuration of 0 and address number areas 205 and 207.

FIG. 4 is a diagram showing an optical disc 200 having a structure in which a groove part is switched to a land part in a part of one circumference of the disc according to the third embodiment of the present invention.

FIG. 5 is a block diagram showing a tracking position determiner 350 according to Embodiment 3 of the present invention.

FIG. 6 is a diagram showing a part of a master manufactured according to a fourth embodiment of the present invention and a master manufacturing procedure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 100 Optical disk 101 1st zone 102 2nd zone 103 Sector which divided the 1st zone into 12 104 Sector which divided the 2nd zone into 16 105-1 Address number area 106 Data recording area 107 Address mark area 108 Sector number area 109 First track number area 110 Second track number area 111 Groove

Claims (9)

[Claims] 1. An optical disc having at least one area along a radiation direction and having a plurality of tracks in the at least one area, wherein the at least one area is formed radially on the plurality of tracks. In the address area, data common to tracks adjacent to each other among the plurality of tracks is recorded at the same radial position on the adjacent track. An optical disc in which different data between tracks is recorded at different radial positions on the adjacent track. 2. The plurality of tracks include a plurality of first tracks and a plurality of second tracks, and each of the plurality of first tracks and each of the plurality of second tracks alternate. The address area is data common to the plurality of first tracks and the plurality of second tracks and located at the same radial position, and the plurality of 2. The optical disc according to claim 1, wherein the optical disc includes different data between one track and the plurality of second tracks, the data being located at different radial positions. 3. The at least one area further has a data recording area different from the address area. In the data recording area, the first track is formed by a groove, and the second track is formed by a groove. 3. The optical disc according to claim 2, wherein the optical disc is formed between the grooves of the first track. 4. The first area of the address area where different data is recorded between the first track and the second track among the address areas arranged on the second track. 4. The optical disc according to claim 3, wherein the track is constituted by a groove. 5. A reproducing apparatus for reproducing data recorded on an optical disk having at least one area along a radiation direction and having a plurality of tracks in the at least one area, wherein the optical disk comprises: One area includes an address area radially arranged on the plurality of tracks, and in the address area, data common to tracks adjacent to each other among the plurality of tracks is stored in the adjacent track. Different data between the adjacent tracks are recorded at different radial positions on the adjacent track, and the polarity of tracking between the adjacent tracks is at least The playback device has a part that is changed in the address area of the adjacent track. A reproducing unit that detects a recording position of the read data, and a determining unit that determines a tracking polarity of a track being reproduced among the plurality of tracks based on an output from the detecting unit. 6. The error detecting section for detecting error information of data recorded in an address area corresponding to each of the adjacent tracks, wherein the recording position of the data is an error of the data. The reproduction device according to claim 5, wherein the reproduction device is detected based on the detection of the information. 7. A method of producing a master of an optical disk, comprising: (a) providing a substrate having a photoresist film formed on a surface thereof; and (b) positioning the substrate relative to a beam. (C) forming a first trajectory on the photoresist film by irradiating the photoresist film on the substrate with the beam; and (d) forming a part on the first trajectory. Forming a second trajectory on the photoresist film by further irradiating the beam so that the beams overlap each other, and (e) fabricating a master disk of the optical disk using the photoresist film. And a method for producing an optical disc master. 8. The master of the optical disc according to claim 7, wherein the step (d) includes forming the second trajectory by irradiating the beam with the beam deflected in a radial direction of the substrate. Production method. 9. The method according to claim 7, wherein the step (d) includes forming a second trajectory larger than a half width of the beam on a photoresist film.