JP3210608B2 - Optical disk and optical disk device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc and an optical disc apparatus, for example, a phase-change optical disc,
It can be applied to this optical disk system. The present invention provides an information recording surface even when data is recorded at a higher density than before by preformatting address data using a pit row and forming a groove formed by a laser beam guide groove in a meandering manner. Can be used effectively to reliably detect the address recorded on the optical disk.

[0002]

2. Description of the Related Art Conventionally, in an optical disk apparatus for recording information at high density, desired data is recorded in sector units based on address data previously recorded on an optical disk by pre-pits.

That is, in this type of optical disc, sectors are formed by dividing an information recording surface at predetermined angular intervals. In each sector, address data is recorded at the beginning by pre-pits, and a subsequent area is allocated to a user area.

[0004] The optical disk device blocks user data that is sequentially input in units of 2048 bytes, and uses the address data recorded on the optical disk as a reference to store the data.
A block of 048 bytes is recorded in the user area of each sector.

[0005]

As an optical disk device of this type, a DVD (Digital Versatile Disc) is used.
e) is proposed. This DVD has a wavelength of 650 [n
m] is irradiated on the optical disk by an optical system having a numerical aperture of 0.6 so that 2.6 MB of data can be recorded on one side. In this DVD, a video signal of about one hour can be recorded on one side.

On the other hand, in a home video tape recorder, since the basic recording time is two hours, more capacity is required to ensure the same usability as the video tape recorder in the optical disk device. Must be recordable. Further, in order to effectively execute a process such as editing using a random access function or the like which is a feature of the optical disc, it is necessary to record a video signal for about 3 hours. In this case, with reference to a DVD system, it is necessary to set data of about 8 [GB] to be recordable.

In this case, it is conceivable to further improve the recording density of this type of optical disk by accessing the optical disk with an optical system having a high numerical aperture. In this case, it is conceivable to form an optical disc by setting the thickness of the light transmitting layer to about 0.1 [mm], for example, because the skew margin allowed for the optical disc apparatus is reduced.

However, the thickness of the light transmitting layer is set to 0.1 [mm].
If it is set to such a degree, it becomes difficult to correctly reproduce address data and user data due to the influence of dust and the like attached to the disk surface. In such a case, it is considered that the effect of dust and the like can be reduced for the user data by enhancing the error correction capability. However, as for the address data, if the error correction capability is enhanced, the capacity of the user area is reduced correspondingly, which makes it difficult to use the information recording surface efficiently.

The present invention has been made in view of the above points, and even when data is recorded at a higher density than before,
It is an object of the present invention to propose an optical disk and an optical disk device capable of reliably detecting an address recorded on an optical disk by effectively utilizing an information recording surface.

[0010]

According to the first aspect of the present invention, there is provided an optical disc which is applied to an optical disc.
A groove serving as a guide groove for a laser beam is formed on an information recording surface concentrically or spirally in a meandering manner, the information recording surface is divided at predetermined angular intervals, and a user data recording area and address data are radially formed. Are formed alternately in the recording area of the address data, and a pit string corresponding to the address data having at least the time information or the position information is formed in the recording area of the address data, and the track pitch by the groove is 0.64. [Μm] or less, the light transmitting layer is formed with a thickness of 10 to 177 [μm], and the meandering of the groove is formed according to a sinusoidal signal of a single frequency and converted into the rotation angle of the optical disk. The meandering cycle of
Within a predetermined range, a groove is formed so that the inner circumference side and the outer circumference side of the optical disk are equal, and the meandering of the groove converted into the rotation angle of the optical disk is the same phase between adjacent grooves within a predetermined range. A groove is formed so as to form a groove.

[0011]

The width of the groove is set to be substantially equal to the width of the land between adjacent grooves.

The pit train of each address data is formed by sequentially arranging a pit train based on time information or position information of a track by a groove and a pit train based on time information or position information of a track by a land between grooves.

If a groove is formed meandering and a pit row corresponding to the address data is formed, even if the address information cannot be read due to the influence of dust on the disk surface, the previously detected address data and the groove are used. Using the synchronization information, a correct address can be detected by the synchronization processing, and thereby the recording / reproducing position can be specified. In addition, the address data may have a very low error rate address quality, and the bit length can be shortened by the amount of the synchronization information allocated to the greave. This makes it possible to use the information recording surface efficiently and reliably detect the address recorded on the optical disk. Further, accurate recording / reproducing clock information, that is, angle information, based on the reference position information of the disk can be obtained from the frequency information due to the groove meandering. With this clock information, high-density recording and reproduction can be performed without redundancy. Further, the rotation of the optical disk can be controlled with high accuracy based on the meandering of the groove.

At this time, if the meandering period of the groove converted into the rotation angle of the optical disk is equal in the predetermined range on the inner circumferential side and the outer circumferential side, and the phase is the same between adjacent grooves. The crosstalk between the pit train and the groove can be reduced, and information can be recorded at a high density. For example, when only a reproduction signal having a lower S / N than that of the pit train can be obtained from the user data area, the accuracy is improved. By reproducing a high clock, the bit error rate can be improved.
Also, when increasing the recording capacity by zoning,
Crosstalk can be reduced.

If the width of a groove and the width of a land between adjacent grooves are set to be substantially equal, both tracks of the land and the groove can be used as recording / reproducing tracks, and the recording density can be improved. Can be.

In this case or the like, the pit train of each address data is sequentially arranged by a pit train based on time information or position information of a track by a groove and a pit train based on time information or position information of a track by a land between grooves. If formed, address data can be correctly reproduced from the pit train.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(1) First Embodiment (1-1) Configuration of First Embodiment FIG. 2 is a block diagram showing a mastering device according to a first embodiment of the present invention. In the manufacturing process of the optical disk according to this embodiment, the master disk 2 is exposed by the mastering device 1 and an optical disk is manufactured from the master disk 2.

In the mastering apparatus 1, the master disc 2 is formed by applying a resist on a surface of a glass substrate, for example, and is driven to rotate by a spindle motor 3 at a constant angular velocity.

The optical head 4 irradiates a laser beam L to the disk master 2 while being sequentially displaced from the inner circumference to the outer circumference of the disk master 2 in synchronization with the rotation of the disk master 2 by a predetermined thread mechanism. I do. Thus, the optical head 4 forms a spiral track on the outer peripheral side from the inner peripheral side of the master disc 2. At this time, the optical head 4 is controlled by a threat mechanism so as to be displaced by about 1.0 [μm] in a cycle of the disk master 2 making one rotation.
The track is formed by 5 [μm]. The track pitch in the case of this land-groove recording is a track pitch of 0.74 [μ
m] is 1.48 times.

Thus, the mastering apparatus 1 records desired data at a linear recording density of about 0.21 [μm / bit] on the optical disk prepared from the master disk 2, and obtains the following equation from the following equation. Data of a capacity of 8 GB or more can be recorded on this optical disc.

[0023]

(Equation 1)

Here, the numeral 4.7 is the recording capacity [GB] of the DVD, which is the numeral 0.74 and the numeral 0.267.
Is the track pitch [μm] and the linear recording density [μm / bit] of the DVD. Therefore, in equation (1),
This indicates the recording capacity by the same data processing as the DVD.

Further, at this time, when an optical disc is produced from the master disc 2, the groove formed by the exposure of the laser beam L is substantially equal to the land width between adjacent grooves. Then, the spot diameter of the laser beam L is set. Here, the spot shape and light amount of the laser beam are set so that the effective exposure range by the laser beam increases by about 120% with respect to the width of the groove as the final target.

Further, the optical head 4 is configured such that the optical system is movable in the radial direction of the master disc 2.

The drive circuit 5 drives the optical head 4 according to the drive signal SD. At this time, the drive circuit 5 switches the driving conditions of the optical head 4 in accordance with the laser beam irradiation position at a timing synchronized with the rotation of the disk master 2, thereby zoning the disk master 2 as shown in FIG. I do. In FIG. 1, the description of the grooves and pits is simplified.

That is, in this mastering apparatus 1, a radius of 24 [m] is used for an optical disc having a diameter of 120 [mm].
Tracks are sequentially formed on the master disc 2 such that an area of m] to 58 [mm] is set on the information recording surface. At this time, the drive circuit 5 switches the drive conditions of the optical head 4 such that the information recording surface is divided into radial areas to form a sector structure. Further, by changing the timing of the switching stepwise from the inner side to the outer side in order,
The information recording surface is divided concentrically into 14 zones Z0 to Z
forming n.

Thus, the drive circuit 5 forms nine sectors on one track in the innermost zone Z0,
As it is sequentially displaced to the outer peripheral zone Z1,.
The number of sectors on the track is increased by one.

Each sector starts with an address area AR as shown by enlarging the sector boundary by arrows A and B.
2 and the remaining area AR1 is allocated to the user area. The drive circuit 5 controls the user area AR1 under the control of a system control circuit (not shown).
In, the laser beam irradiation position is displaced by the drive signal SD, whereby the user area AR1 is formed to meander a groove.

In the address area AR2, the displacement of the irradiation position of the laser beam is stopped in the first half of the address area AR2, and the light amount of the laser beam is intermittently raised by the drive signal SD, whereby the track center by the groove is formed. A pit row is formed on the top. Also, in the latter half of the address area AR2, the laser beam irradiation position is displaced onto the track center by the land on the inner peripheral side, and the light amount of the laser beam is intermittently started by the drive signal SD. A pit row is formed.

Thus, the drive circuit 5 records the address data of the sector by the following groove on the corresponding track center in the first half of the address area AR2 in the form of a pit row, and the second half of the address area AR2. The address data of the sector by the land on the peripheral side is recorded on a corresponding track center by a pit row.

At this time, the drive circuit 5 has a wavelength of 650 [nm] when producing an optical disk from the master disk 2.
The light amount at the time of laser beam irradiation is set such that the depth of the pits and grooves becomes 1/6 to 1/5 wavelength with respect to the laser beam. The grooves are formed so that the amplitude is 15 to 30 [nm].

The wobble signal generation circuit 7 outputs a sine wave signal of a predetermined frequency synchronized with the rotation of the master disc 2 as a wobble signal WB. At this time, the wobble signal generating circuit 7 sequentially increases the frequency of the wobble signal WB and outputs the frequency in accordance with the zoning described above with reference to FIG. Thereby, the wobble signal generation circuit 7
The laser beam irradiation position is displaced by the wobble signal WB to meander 397 cycles per sector.

Thus, in the address area (header area) AR2, a length corresponding to five periods of the groove is allocated, and in the track of the innermost zone Z0,
The groove is formed so as to meander 3573 cycles, and the groove is formed so that the meandering of the groove is sequentially increased by 397 cycles per track as moving to the zone on the outer peripheral side. In this embodiment, 25 bytes of data are allocated to the user area AR1 for one cycle of the groove meandering, and one cycle is formed with a length of about 42 [μm].

The address signal generation circuit 6 generates and outputs an address signal SA whose value sequentially changes according to the displacement of the optical head 4 under the control of the system control circuit. That is, the address signal generation circuit 6 receives a timing signal (comprising an FG signal or the like) synchronized with the rotation of the master disk 2 from the spindle motor 3 or the like, and counts this timing signal by a predetermined counter. Thereby, the address signal generation circuit 6 generates the address data ID of the laser beam irradiation position as shown in FIG. 3 (FIGS. 3A and 3C).
1) and (C2)). The numbers shown in FIG. 3 are the number of bytes of each data.

The address signal generation circuit 6 adds the sector mark SM, the synchronization timing data VFO, the address mark AM, and the postamble PA to the address data ID, and the first half and the second half of the address area AR2, respectively. Is generated (FIGS. 3 (B), (C1) and (C2)). Here, the address signal generation circuit 6 forms each sector header with 62 bytes, thereby forming data to be recorded in the address area AR2 with 8 Kbytes. The sector mark SM is set to indicate the start of the sector header,
Four bytes are allocated. The synchronization timing data VFO is arranged for locking a PLL circuit in the optical disk device, and 26 bytes and 16 bytes are allocated from the head side, respectively.

The address mark AM is a synchronizing signal of the address, and one byte is allocated. The address data ID is 6 bytes, of which 2 bytes are an error detection code. The address data ID is such that the same data is repeatedly recorded twice, thereby improving the reliability. The postamble PA is arranged to set the polarity of the signal, and is assigned one byte.

The address signal generating circuit 6 converts the sector header thus generated into a serial data string, and modulates this serial data string in a predetermined format. Further, the address signal generation circuit 6 outputs the modulated signal as an address signal SA. At this time, the address signal generation circuit 6 outputs the address signal SA at a timing corresponding to the scanning of the laser beam L.

The synthesizing circuit 8 outputs the wobble signal WB
And the address signal SA to generate a drive signal SD including a displacement signal for displacing the optical system of the optical head 4 and a light amount control signal for controlling the light amount of the laser beam. Output to the drive circuit 5.

As a result, the optical disk produced from the disk master 2 is preformatted so that the information recording surface is divided concentrically and the number of sectors increases gradually from the inner peripheral zone toward the outer peripheral zone. It is formed.
Further, at the head of each sector, an address area AR2 is formed. The address of the sector by the following groove and the address of the sector by the following land are recorded in this address area AR2, and desired data is recorded in the following user area AR1. Will be.

For this user area AR1 (FIG. 3
(B)) In this embodiment, with a gap of 0.5 byte and 8 bytes, a guard of 24 bytes, 25 bytes,
Byte VFO, 2 bytes of synchronization byte, 9672 bytes of user data, 1 byte of postamble (P
A), a 48-byte guard, and a 16-byte buffer are sequentially allocated.

Here, the gap is a land-groove switching area and a laser beam intensity switching area, and the guard suppresses the fluidity of the recording material due to overwriting when a phase change medium is used as the recording medium. It is arranged to improve the overwrite cycle of the recording area. The synchronization byte is placed for locking the PLL circuit in the optical disc device, the postamble is placed for polarity setting, and the buffer is
This is a redundant area of a recording area for absorbing jitter due to eccentricity or the like.

FIG. 4 is a perspective view showing an optical disk produced from the master disk 2, and a sectional view showing a section of a groove. This optical disc is formed entirely with a thickness of 1.2 mm. In the case of a phase-change optical disc, an aluminum film, a ZnS—SiO ₂ film, a GeSbTe film, a ZnS—S film are formed on a disc substrate.
An iO ₂ film is sequentially formed to form an information recording surface. In a magneto-optical disk, an aluminum film, a SiN film, a TbFeCo film, and a SiN film are sequentially formed on a disk substrate to form an information recording surface. In the case of a write-once type, aluminum or gold sputtering is performed on the disk substrate. An information recording surface is created by sequentially forming a film and a predetermined organic dye film.

Further, a light transmitting layer having a thickness of about 0.1 [mm] is formed on the information recording layer to transmit the laser beam and guide the laser beam to the information recording surface. Thus, the optical disk according to this embodiment can effectively avoid the influence of skew and store desired data on this information recording surface even when a laser beam is irradiated from a high numerical aperture optical system via a light transmission layer. Recording and reproduction can be performed reliably.

This optical disk has a diameter of 120 [m
m] and a radius of 24 [mm] to 58 [mm]
Area is allocated to the recording area.

Further, the optical disk is stored and stored in a predetermined cartridge formed so as to be able to identify the type of the optical disk, and is formed so as to be loaded together with the cartridge into the optical disk device, thereby providing an optical system having a high numerical aperture. In this case, the influence of dust and the like can be effectively avoided even when the access is made.

As described above, the optical disk is formed so that the crystal structure of the information recording surface is locally changed by laser beam irradiation to record desired data in the phase change type optical disk. It is formed so that data recorded by detecting a change can be reproduced.

In a magneto-optical disk, a magnetic field is applied to a laser beam irradiation position so that desired data can be thermomagnetically recorded, and the polarization plane of return light is detected to utilize the magnetic Kerr effect. It is formed so that the recorded data can be reproduced. In the case of a write-once type,
The information recording surface is locally destroyed by laser beam irradiation so that desired data can be recorded, and the recorded data can be reproduced by detecting a change in the amount of return light.

In these cases, in the optical disk, the disk master 2 is driven to rotate under the condition of a constant angular velocity, and
The frequency of the wobble signal is switched step by step,
A groove is formed by the wobble signal WB. As a result, the optical disk is zoned so that the meandering period of the groove converted into the rotation angle of the optical disk is formed in each zone.

FIG. 5 is a block diagram mainly showing a wobble signal processing system in an optical disk apparatus for accessing the optical disk manufactured as described above. In the optical disk device 10, the optical head 11 irradiates the optical disk 12 with a laser beam and receives the return light.

That is, as shown in FIG.
, The semiconductor laser 13 generates a predetermined driving signal SL
And emits a laser beam having a wavelength of 650 [nm]. At this time, the semiconductor laser 13 emits a laser beam with a constant light amount during reproduction. On the other hand, at the time of recording, a laser beam is emitted by intermittently increasing the amount of light, and in this embodiment, pits or marks are formed on the information recording device of the optical disk 12 by the rise of the amount of laser beam. It can be formed.

The subsequent collimator lens 14 converts the laser beam emitted from the semiconductor laser 13 into a parallel beam, and the subsequent shaping lens 15 corrects the astigmatism of the laser beam, transmits the laser beam through the beam splitter 16 and outputs the objective beam. The light exits to the lens 17.

The objective lens 17 focuses the laser beam on the information recording surface of the optical disk 12 and receives the return light. Thus, in the optical disk device 10, when the optical disk 12 is a read-only optical disk, data recorded on the optical disk 12 can be reproduced according to a change in the amount of the return light. When the optical disk 12 is a phase-change type optical disk, desired data can be recorded by locally changing the crystal structure at the laser beam irradiation position, and the recorded data can be reproduced according to the change in the amount of return light. It has been done.

Further, when the optical disc 12 is a write-once optical disc, the laser beam irradiation position is locally destroyed to record desired data, and the recorded data can be reproduced according to a change in the amount of return light. ing. On the other hand, when the optical disk 12 is a magneto-optical disk, the modulation coil 18 arranged close to the objective lens 17 is driven by a predetermined drive circuit 19 to apply a predetermined modulation magnetic field to the laser beam irradiation position. Desired data is recorded by applying the thermomagnetic recording technique, and the recorded data can be reproduced by detecting a change in the polarization plane of the return light.

Accordingly, the beam splitter 16 transmits the laser beam incident from the shaping lens 15 and emits it to the objective lens 17, while reflecting the return light incident from the objective lens 17 to separate the optical path, and The light is emitted to the splitter 20.

The beam splitter 20 transmits and reflects this return light, and separates the return light into two light beams and emits them.

The lens 21 receives the return light reflected by the beam splitter 20, and converts the return light into a convergent light beam. The cylindrical lens 22 gives astigmatism to the return light emitted from the lens 21. The light detector 23 is
The return light emitted from the cylindrical lens 22 is received.

Here, the photodetector 23 divides the light receiving surface into a predetermined shape, and can output the light receiving result of each divided light receiving surface. Thus, the photodetector 23 performs a current-to-voltage conversion of the light-receiving result of each light-receiving surface by a current-to-voltage conversion circuit (not shown), and then performs addition and subtraction processing by a matrix circuit, so that the signal level changes according to the amount of return light. A signal RF, a push-pull signal PP whose signal level changes according to the displacement of the laser beam irradiation position with respect to the groove or the pit row, and a focus error signal FE whose signal level changes according to the defocus amount are detected. .

On the other hand, the half-wave plate 25 receives the return light transmitted through the beam splitter 20 and changes the polarization plane of the return light to separate the return light in the polarization beam splitter 27 described later. Light is emitted by a suitable polarization plane. The lens 26 converts return light emitted from the half-wave plate 25 into a convergent light beam. Polarizing beam splitter 27
Receives the return light, reflects a predetermined polarization component and transmits the remainder, and thereby separates the return light into two light beams whose light amount changes complementarily according to the polarization plane.

The photodetectors 28 and 29 respectively receive the two light beams separated by the polarization beam splitter 27 and output a light reception result whose signal level changes according to the amount of received light. The differential amplifier 30 receives the light reception results of the two photodetectors 28 and 29 via the current-voltage conversion circuit and obtains the differential amplification results, so that the signal level is changed according to the polarization plane of the return light. The changing reproduction signal MO is output.

Thus, the optical head 11 can record desired data on various optical disks 12 and reproduce the recorded data.

FIG. 7 shows the objective lens 1 of the optical head 11.
FIG. 7 is a cross-sectional view illustrating a peripheral configuration of a seventh embodiment. This objective lens 17
Is composed of a first lens 17A and a second lens 17B. Here, the first lens 17A and the second lens 1
7B is formed of an aspherical plastic lens or a glass mold lens, is integrally held by a predetermined holding member 17C, and is movable vertically and horizontally on the drawing by a drive actuator 17D. Thereby, in the optical disc device 10, the first lens 17A and the second
The tracking control and the focus control can be performed by integrally moving the lens 17B.

In the first lens 17A and the second lens 17B, the second lens 17B on the laser beam incident side has a relatively large diameter, whereas the first lens 17A on the optical disk 12 has a small diameter. Formed by caliber,
The focal lengths and intervals are set so that the numerical aperture of the objective lens 17 as a whole is 0.78.

Thus, the objective lens 17 can satisfy the following relational expression. Where λ is
The wavelength of the laser beam, NA is the numerical aperture of the objective lens 17, t is the thickness of the light transmitting layer of the optical disk 12, and Δt is the variation of t. Θ is a skew margin of the optical disc 12.

[0066]

(Equation 2)

[0067]

(Equation 3)

Equation (2) shows the relationship between the optical system and the skew margin θ at which the optical disk can be stably accessed (Japanese Patent Laid-Open Publication No. 3-225650). Has a skew margin θ of about 0.6 degrees on the market. In a DVD, the skew margin θ is set to 0.4 degrees. Thereby, in this embodiment, the thickness of the light transmission layer of the optical disc 12 is set to 0.1 [m
m] and the numerical aperture NA of the optical system is set to a large value, so that the optical disk 12 can be accessed sufficiently stably for practical use.

The equation (3) shows the variation of the thickness t of the light transmitting layer which can be tolerated in the optical system.
Is a value calculated on the basis of a compact disc, Δt is ± 100 [μm] for a compact disc,
For DVD, it is ± 30 [μm]. Thereby, in the optical disk device 10, even if the thickness t of the light transmitting layer varies, the optical disk 12 can be accessed stably.

Thus, the optical head 11 irradiates the optical disk 12 with a laser beam having a wavelength of 650 [nm] via an optical system having a numerical aperture of 0.78 so that the following relational expression is satisfied. It has been done.

[0071]

(Equation 4)

Here, the numeral 4.7 is the recording capacity [GB] of the DVD, and the numerals 0.65 and 0.6 are the wavelength of the laser beam in the DVD and the numerical aperture of the optical system, respectively. Thereby, in the optical head 11,
Approximately 8 data processed using the same format as DVD
The recording capacity of [GB] can be ensured.

In the objective lens 17 thus formed, the first lens 17A is held so as to protrude toward the optical disk 12, and is thereby held at the working distance WD required by the numerical aperture. I have. In this embodiment, the characteristics and arrangement of the first lens 17A and the second lens 17B are selected.
The working distance WD is set to about 560 [μm], whereby the optical head 11
The eccentricity tolerance between the lens surfaces, the surface angle tolerance, and the curvature of the lens can be set within the range that can be mass-produced practically, and the overall shape can be reduced in size. Has been made to be able to effectively avoid.

That is, in the optical head, when the numerical aperture is increased, when the laser beam having the same beam diameter is incident, it is necessary to dispose the objective lens closer to the information recording surface of the optical disk. Thus, if an optical head is to be arranged with a sufficient distance from the optical disk, the beam diameter of the laser beam must be significantly increased as compared with the conventional case. On the other hand, the practical upper limit of the laser beam diameter is about 4.5 [mm], which is almost the same as that of a DVD.

On the other hand, when the optical head is arranged close to the optical disk to reduce the diameter of the laser beam and the size of the optical system, the production accuracy of the objective lens is correspondingly reduced. However, there is a possibility that the arrangement accuracy becomes higher and the optical head collides with the optical disk. Accordingly, in this embodiment, the working distance WD
Is set to about 560 [μm] to satisfy these conditions.

Further, the optical disk 12 of the first lens 17A
The side lens surface is formed flat so that focus control can be reliably performed, and even if the optical disk 12 is skewed, it does not collide with the surface of the light transmitting layer.

Further, the objective lens 17 is connected to the optical disk 12
The diameter of the lens on the optical disk 12 side is formed small enough to guide the laser beam to the optical disk 12.

The modulation coil 18 is connected to the first lens 17A.
And the side surface on the optical disk 12 side is substantially flat with the lens surface of the first lens 17A. Thereby, the modulation coil 18 is connected to the first lens 1.
The optical disk 12 does not protrude from the lens surface of the optical disk 7A.
The modulation magnetic field can be efficiently applied to the laser beam irradiation position.

Further, the temperature rise of the modulation coil 18 is reduced by the heat radiating plate 17E disposed on the side of the second lens 17B so as to surround the first lens 17A. It is made to be able to stay in a sufficient range.

In the optical disk device 10 (FIG. 5), the spindle motor 33 drives the optical disk 12 to rotate under the control of the system control circuit 34. At this time, the spindle motor 33 drives the optical disc 12 to rotate so that the write / read clock R / WCK generated by the PLL circuit 35 has a constant frequency, and thereby drives the optical disc 12 by a so-called ZCLV (Zone Constant Liner Velocity) technique. Drive rotationally. Here, this ZC
The zoning by the LV corresponds to the zoning described with reference to FIG.

The sled motor 36 moves the optical head 11 in the radial direction of the optical disk 12 under the control of the system control circuit 34, so that the optical disk device 10 can seek.

The address detection circuit 37 receives the reproduction signal RF whose signal level changes in accordance with the amount of return light from the optical head 11, and binarizes the reproduction signal RF. 2 more
The address data ID is detected from the coded signal based on the synchronization signal assigned to the sector header and output to the system control circuit 34, and the detected timing is notified to the cluster counter 38. As a result, the optical disk device 10 uses the system control circuit 34 to store the address data ID preformatted on the optical disk 12.
The laser beam irradiation position can be specified on the basis of the data, and the cluster counter 38 can confirm the timing of the sector.

Further, when outputting the address data ID, the address detection circuit 37 performs an error detection process using an error detection code assigned to each address data ID, and selectively selects an address data ID determined to be correct. Output.

The wobble signal detection circuit 39 supplies the push-pull signal PP output from the optical head 11 to the band-pass filter 39A, where the wobble signal WB is extracted. Further, the wobble signal detection circuit 39 binarizes the wobble signal WB with reference to the 0 level in the subsequent comparison circuit (COM) 39B, thereby extracting edge information of the wobble signal WB.

The wobbling cycle detection circuit 40 receives the binarized binary signal S1 and receives the binary signal S1.
By determining the timing of the corresponding edge with reference to the timing of each edge of No. 1, it is determined whether or not the wobble signal WB changes at the correct cycle. Further, the wobbling cycle detection circuit 40 selectively outputs edge information determined as a correct cycle to the PLL circuit 35. Thus, the wobbling cycle detection circuit 40 prevents the clock CK from being displaced by dust or the like attached to the optical disc 12.

The PLL circuit 35 supplies the binary signal output from the wobbling cycle detection circuit 40 to the phase comparison circuit (PC) 35A, where it compares the phase with the clock CK output from the frequency division circuit 35B. Here the frequency divider 3
5B, by the setting of the system control circuit 34,
A predetermined clock CK is output by switching the frequency division ratio.

As a result, in the PLL circuit 35, the low-frequency component of the phase comparison result output from the phase comparison circuit 35A is extracted by the low-pass filter (LPF) 35C, and the voltage-controlled oscillation circuit ( VCO) 36D is controlled. Further, the oscillation output of the voltage control type oscillation circuit 36D is divided by a frequency dividing circuit 35B.
, So that a highly accurate clock CK can be generated.

In the PLL circuit 35, the frequency dividing circuit 3
5B is set according to the setting of the system control circuit 34 so as to correspond to the zoning explained with reference to FIG. As a result, the PLL circuit 35 sequentially and stepwisely shifts the laser beam irradiation position toward the outer peripheral side of the optical disc 12.
The frequency of the oscillation output of the voltage-controlled oscillation circuit 36D is increased with respect to the frequency of the wobble signal WB,
This oscillation output is used to write and read clock R / W C
Output as K.

In the optical disk device 10, the write / read clock R is
By rotating the optical disc 12 so that / W CK has a constant frequency, and by recording desired data with reference to the write / read clock R / W CK, line recording is performed on the inner and outer peripheral sides. The density is not largely changed, and the recording density can be increased accordingly.

The cluster counter 38 counts the write / read clock R / W CK based on the detection result of the address detection circuit 37, thereby providing high accuracy based on the write / read clock R / W CK. Specify the laser beam irradiation position. Further, the cluster counter 38 calculates, based on the count result,
A cluster start pulse is output to the system control circuit 34. Here, the cluster is a unit for recording and reproducing data on and from the optical disk 12, and the cluster start pulse is a pulse for instructing the start timing of the cluster.

In this process, the cluster counter 38
In the case where the sector detection timing is not detected by the address detection circuit 37 due to, for example, dust on the disk surface, the cluster start pulse is interpolated by the synchronization process based on the count result of the write / read clock R / WCK. .

The system control circuit 34 is constituted by a computer for controlling the operation of the entire optical disk device 10 and, based on the sequentially input address data ID,
By controlling the operation of the thread motor 36 and the like and switching the overall operation mode, the overall operation is controlled in accordance with the laser beam irradiation position and further by control from an external device.

In this series of processing, the system control circuit 34 switches the frequency division ratio of the frequency dividing circuit 35B according to the frequency division ratio data stored in the memory 42 according to the laser beam irradiation position based on the address data ID. .

As a result, the system control circuit 34
Zones Z0, Z1,..., Zn-1,
In order to correspond to Zn, the rotation speed of the optical disk is gradually reduced from the inner circumference side to the outer circumference zone so that each sector has the same recording density in the inner circumference zone and the outer circumference zone. Set to.

At this time, by controlling the writing and reading in accordance with the cluster start pulse output from the cluster counter 38, the data of one cluster is stored in four consecutive sectors based on the address area AR2 set in each sector. Assign. Thus, the system control circuit 34 sequentially increases the number of clusters assigned to each zone from the inner zone to the outer zone.

Further, the system control circuit 34 instructs a tracking servo circuit (not shown) to switch the movable direction of the objective lens 17 with respect to the polarity of the tracking error signal, thereby scanning the laser beam with the groove and the land between the grooves. Switching control is performed between and.
Thus, the optical disk device 10 can perform so-called land / groove recording.

FIG. 8 is a block diagram showing a recording / reproducing system of the optical disk device 10. This optical disk device 10
In, the disc discriminator 50 identifies the type of the optical disc 12 from, for example, a recess formed in the cartridge,
The identification signal is output to the system control circuit 34. Thus, the optical disk device 10 can switch the operation of the recording / reproducing system according to the type of the loaded optical disk 12, and can access various optical disks.

Here, the encoder 51 inputs an input signal SIN composed of a video signal and an audio signal from an external device at the time of recording, editing, and the like, and after performing an analog-to-digital conversion process on the video signal and the audio signal,
User data DU is generated by data compression according to a format prescribed by MPEG (Moving Picture Experts Group).

On the other hand, the decoder 52 expands the user data DU output from the recording / reproducing circuit 53 at the time of reproduction and editing, according to a format prescribed in MPEG, and reproduces the digital video signal at the time of reproduction and editing. , A digital audio signal, and converts the digital video signal and the digital audio signal into an analog signal SOUT and outputs it.

The recording / reproducing circuit 53 stores the user data DU output from the encoder 51 in the memory 54 at the time of recording and editing, and processes the user data DU in a predetermined block unit to record it on the optical disk 12.

That is, as shown in FIG. 9, the recording / reproducing circuit 53 sequentially divides the user data DU into 2048-byte units, and adds 16-byte address data and an error detection code to each block. The recording / reproducing circuit 53 forms a sector data block using the 2048 bytes + 16 bytes. The address data is the address data of this sector data block. Note that the sector based on the user data DU is different from the sector based on the preformat described above with reference to FIG. The error detection code is an error detection code of the address data.

Further, as shown in FIG. 10, the recording / reproducing circuit 53 forms an ECC data block (182 bytes × 208 bytes) by 16 sector data blocks. In other words, the recording / reproducing circuit 53
16 sector data blocks of byte + 16 bytes are sequentially arranged in raster scanning order in units of 172 bytes,
In this lateral direction, an error correction code (PI) consisting of an inner code is generated. Further, an error correction code (PO) consisting of an outer code is generated in the vertical direction.

The recording / reproducing circuit 53 interleaves the ECC blocks to form a frame structure shown in FIG. That is, the recording / reproducing circuit 53 allocates a 2-byte frame synchronization signal (FS) to each of the 91 bytes of the ECC data block of 182 bytes × 208 bytes.
6 frames are formed. Thereby, the recording / reproducing circuit 53
Forms data of one cluster by the frame structure shown in FIG. 11, and allocates this one cluster to four consecutive sectors.

At this time, the recording / reproducing circuit 53 assigns predetermined fixed value data as necessary, and processes continuous data by the sector structure described above with reference to FIG.
Further, the recording / reproducing circuit 53 modulates (1, 7) RLL the data string having such an arrangement, and then performs arithmetic processing between successive bits and outputs the result. At the time of this output, the data is output at a data transfer rate of 11.08 [Mbps] in terms of the user data DU, so that the encoder 51
It outputs intermittently at a higher transfer rate than the data transfer rate of the input user data DU. As a result, the recording / reproducing circuit 53 is able to intermittently record the user data DU and make use of the remaining free time to perform a seek operation. Even when detracking due to vibration or the like, the continuous user data is not interrupted. It can be recorded.

At the time of this data recording, the recording / reproducing circuit 53
Is the write / read clock R described above with reference to FIG.
The output of data modulated on the basis of / W CK is started, and under the control of the system control circuit 34, the output of data modulated on the basis of the timing detected by the cluster counter 38 is started.

Further, at the time of reproduction, the recording / reproducing circuit 53 amplifies the reproduction signals RF and MO input from the optical head 11 and then binarizes them to generate a binarized signal. Further, a clock is reproduced from the reproduction signals RF and MO based on the binarized signal. Thus, the reproduced clock corresponds to the write / read clock R / WCK. Further, the reproduced data is detected by sequentially latching the binarized signal based on the reproduced clock.

The recording / reproducing circuit 53 is a PRML (Partial-R
The reproduction data is subjected to an arithmetic processing at the time of recording and an arithmetic processing in consideration of the transfer characteristics of the recording / reproducing system by applying the technique of "esponse maximum-likelihood", and then decoded to generate decoded data. Further, the recording / reproducing circuit 53
After deinterleaving the decoded data, the data is subjected to error correction and output to the decoder 52.

Thus, in DVD, (1,
7) The PLL-modulated data is converted to a minimum pit length of 0.4 [μ
m], and if a recording / reproducing system is formed with the same margin as that of a DVD simply by conversion based on the numerical aperture, the shortest pit length is 0.3 [μm] and the linear recording density is 0.23 [μm / Bit], desired data can be recorded and reproduced. On the other hand, if PRML actively uses intersymbol interference, the line recording density of 0.2
A similar margin can be ensured with 3 [μm / bit] or less.

At this time, the recording / reproducing circuit 53 converts the data to 11.08 [Mb
ps], data is intermittently reproduced from the optical disk 12 in cluster units, and the reproduced user data DU is continuously output to the decoder 52.

In this series of processing during reproduction,
When the optical disk 12 is a magneto-optical disk, the recording / reproducing circuit 53 selectively processes the reproduced signal MO whose signal level changes according to the polarization plane under the control of the system control circuit 34 to reproduce the user data DU. . If the optical disc 12 is a read-only optical disc, a write-once type, or a phase change type, the user data DU is reproduced by selectively processing a reproduction signal RF whose signal level changes according to a change in the amount of return light. Further, even when the optical disk 12 is a magneto-optical disk, when reproducing the lead-in area on the inner peripheral side, the reproduction signal RF is selectively processed to reproduce the user data DU.

The address reading circuit 55 generates address data to be added to each sector data block (FIG. 9) at the time of recording and outputs the address data to the recording / reproducing circuit 53. At the time of reproduction, the address data detected by the recording / reproducing circuit 53 is read. Is analyzed and notified to the system control circuit 34.

When writing, when the optical disk 12 is a magneto-optical disk, the laser drive circuit 57 controls the write / read clock R / W under the control of the system control circuit 34.
The semiconductor laser of the optical head 11 is driven at a timing synchronized with CK, whereby the light amount of the laser beam is intermittently started.

The laser drive circuit 57 intermittently sets the light amount of the laser beam by the output data of the recording / reproducing circuit 53 under the control of the system control circuit 34 when the optical disk 12 is of the phase change type or the write-once type during writing. Raise
Thus, the user data DU is recorded on the optical disc 12.

On the other hand, at the time of reading, the laser drive circuit 57 holds the light amount of the laser beam at a constant low level.

The modulation coil driving circuit 56
When 2 is a magneto-optical disk, the recording operation is started under the control of the system control circuit 34, and the modulation coil of the optical head 11 is driven by the output data of the recording / reproducing circuit 53.
Accordingly, the modulation coil driving circuit 56 applies a modulation magnetic field to the laser beam irradiation position where the light amount rises intermittently, and records the user data DU by thermomagnetic recording.

(1-2) Operation of First Embodiment In the above configuration, in the mastering apparatus 1 (FIG. 2), the master disc 2 is driven to rotate under the condition of a constant angular velocity to move from the inner circumference to the outer circumference. By irradiating the laser beam L spirally toward the groove, grooves are formed at intervals of about 1.0 [μm], and the grooves are formed to meander according to the wobble signal WB.

Further, at this time, in the mastering device 1,
A groove formed by exposure to a laser beam L;
So that the spacing between adjacent grooves is almost equal
The spot shape and light amount of the laser beam L are set, whereby the optical disc is formed so that land / groove recording can be performed on the basis of the group. At this time, the data is formed so that data having a capacity of 8 [GB] or more can be recorded by land-groove recording at a linear recording density of about 0.21 [μm / bit] based on the group.

Further, the disk master 2 is driven to rotate under the condition of a constant angular velocity, and the laser beam irradiation position is shifted by the wobble signal WB whose frequency sequentially increases, thereby zoning.
It is formed so that the meandering period of the groove is constant on the inner peripheral side and the outer peripheral side in terms of the rotation angle of the optical disk.

At this time, in the mastering device 1, in the address signal generating circuit 6, an address data ID (FIG. 3A) whose value sequentially changes each time the master disk 2 is rotated is formed, and the synchronization data is added to the address data ID. Are added to form data to be assigned to the address area AR2 (FIG. 1). After this data is further modulated,
After being combined with the wobble signal WB in the combining circuit 8, it is output to the drive circuit 5. As a result, in the mastering device 1, the meandering of the groove is interrupted at a predetermined angular interval, and address data is recorded on the master disk 2 by a pit string. Is formed.

Thus, in the optical disk formed by the master disk 2, when accessing each sector based on the address data, even if the address data cannot be reproduced correctly due to dust or the like, the groove meandering is used as a reference. By the interpolation processing, each sector can be correctly accessed. Therefore, in the address data, even when information is recorded at a high density, the redundancy can be set low, and the address recorded on the optical disk can be reliably detected by effectively utilizing the information recording surface. it can.

When the sector structure is formed in this manner, in the mastering apparatus 1, the master disk 2 is concentrically zoned by switching the frequency of the wobble signal WB, and is shifted from the inner circumferential zone to the outer circumferential zone. A pit row is formed such that the number of sectors increases sequentially. This allows zone C to correspond to this zoning.
The information recording surface can be efficiently used by accessing the optical disk by applying the LV method.

Further, at this time, the address area AR2 is divided into the front and rear areas, and the address data of the sector by the following groove and the sector by the following land are respectively assigned, so that the data is recorded at a high density by the land-groove recording. Even in this case, the address data can be reliably reproduced by effectively avoiding crosstalk from the adjacent track.

At this time, the error detection code is assigned to two bits of the address data ID, and the address data can be surely reproduced by repeatedly assigning the same address data ID to one area. .

Thus, in the manufacturing process of the optical disk according to the present embodiment, the optical disk is created from the master disk 2 by the mastering device 1 through a predetermined process through the sector structure formed on the master disk 2.

In this optical disc (FIG. 4), a light transmitting layer which transmits a laser beam and guides the laser beam to the information recording surface is formed with a thickness of about 0.1 [mm] on the information recording surface. Thus, even when a laser beam is irradiated from an optical system having a high numerical aperture through a light transmission layer, the effect of skew can be effectively avoided and desired data can be reliably recorded and reproduced on this information recording surface. It is formed.

In the optical disk 12, processing such as spindle control is performed in the optical disk device on the basis of the groove wobble generated in this manner. At this time, the PLL circuit 35 performs the processing with the accuracy based on the groove wobble. A high clock CK is generated, and the timing of the sector is detected by the cluster counter 38 (FIG. 6).

That is, in the optical disk device 10 (FIGS. 5 and 6), the optical disk 12 has a wavelength of 650 [nm] via the objective lens 17 having a numerical aperture of 0.78 and a working distance WD set to 560 [μm]. A laser beam is irradiated, the return light is received by the optical head 11, and a reproduction signal RF whose signal level changes according to the amount of return light and a reproduction signal MO whose signal level changes according to the polarization plane of the return light. , A push-pull signal PP whose signal level changes according to the displacement of the laser beam irradiation position with respect to the groove or the pit row, and a focus error signal FE whose signal level changes according to the defocus amount.

From the push-pull signal PP, the wobble signal WB
Is extracted, and the wobble signal WB is binarized to extract edge information. In the subsequent PLL circuit 35, the binary signal S1 having the edge information is phase-synchronized with the output signal CK of the frequency divider 35B, and a write / read clock R / W CK is generated.

At this time, since the wobble signal WB is generated by a carrier signal of a single frequency, in the edge information obtained by binarization, each edge information has correct phase information. As a result, a highly accurate write / read clock R / W CK is generated in phase synchronization with the edge information.

Further, the read / write clock R / W
The CK is counted by the cluster counter 38 based on the frame synchronization timing detected from the address area AR2 in the address detection circuit 37, and thereby the write / read timing in the recording / reproduction circuit 53 (FIG. 11) is set. . At this time, by setting this timing with reference to the clock R / W CK having high accuracy, the optical disk device 10 can determine the laser beam irradiation position with high accuracy and set the writing timing and the like. . Therefore, when recording user data on the optical disc 12 at high density, the user data can be recorded using the information recording surface of the optical disc 12 at high density.

At this time, even when it is difficult for the address detection circuit 37 to correctly detect the frame synchronization timing due to the influence of dust or the like, the clock R / W CK output from the PLL circuit 35 is counted by the cluster counter 38, Correct timing can be detected, so that even when desired data is recorded and reproduced at a high density by an optical system having a high numerical aperture, such data can be reliably recorded and reproduced.

When the wobble signal WB is processed in this way, the frequency division ratio of the frequency dividing circuit 35B is switched in the PLL circuit 35 in accordance with the laser beam irradiation position, whereby the optical disk 12 is rotationally driven by the ZCLV. You.

At this time, since the meandering period of the groove is constant in each region in terms of the rotation angle,
Synchronization of the PLL circuit 35 is quickly formed in each zone, and the access speed can be improved accordingly.
In addition, since the groove meandering is formed at a constant period in terms of the rotation speed of the optical disk 12, the influence from the adjacent track can be effectively avoided.

Thus, in the optical disk device 10 (FIG. 8), by controlling such recording and reproducing timing, at the time of recording, the video signal and the audio signal are data-compressed by the encoder 51 in a format prescribed by MPEG. The data is converted into user data DU, and the user data DU is subjected to modulation processing in a predetermined ECC block unit. Further, when the optical disk 12 is a magneto-optical disk, the modulation coil driving circuit 56 irradiates the laser beam with the light amount of the laser beam intermittently raised from the optical head 11 at the timing synchronized with the write / read clock R / WCK. A modulation magnetic field is applied to the position according to the data of the ECC block that has been subjected to the modulation processing, whereby the user data DU is thermomagnetically recorded.

When the optical disk 12 is of the phase change type or of the write-once type, the write / read clock R / W C
At the timing synchronized with K, the laser drive circuit 57 intermittently switches the light amount of the laser beam according to the data of the ECC block, whereby the user data DU is recorded on the optical disc 12.

At this time, in this optical disk device 10, 1
The user data DU of the ECC block is sequentially allocated to four sectors and recorded. At this time, the timing of the start of recording can be accurately detected by a highly accurate clock. Can be reliably recorded in the corresponding sector even when recording is performed on the optical disc 12 at a high density by an optical system having a high numerical aperture.

On the other hand, during reproduction, the optical disk device 10
In, the corresponding sector is detected in the same manner as during recording. A reproduction signal RF obtained from the optical head 11
Alternatively, after the MO is binarized, a reproduced clock is generated,
Reproduction data is sequentially obtained based on the reproduction clock, and the reproduction data is decoded and output. At this time, the reproduction signal MO obtained from the magneto-optical disk 12 is obtained with a smaller S / N ratio than the reproduction signal RF obtained from the pit train. However, in this embodiment, since the address area AR2 based on the pit row is formed radially in each zone, crosstalk with respect to the reproduced signal MO from this pit row is effectively avoided.

(1-3) Effects of the First Embodiment According to the above configuration, the groove is meandered by a single frequency, and the meandering of the groove is interrupted at a predetermined angular interval, so that the address data by the pit train is obtained. By recording the desired data in each sector due to the pit row, etc., even if the address data cannot be correctly reproduced due to dust or the like, the interpolation processing based on the meandering of the groove is performed by interpolation processing.
Each sector can be accessed correctly. Therefore, in the address data, even when information is recorded at a high density, the redundancy can be set low, and the address recorded on the optical disk can be reliably detected by effectively utilizing the information recording surface. it can.

By generating the read / write clock R / W CK based on the meandering of the groove, a clock with high accuracy can be generated.

Further, by adding an error detection code to the address data ID to be recorded by the pit string and recording the same data repeatedly, when the data is recorded at a high density by that amount, each address data can be detected without fail. can do.

Further, by setting the zoning so that the number of sectors increases toward the outer periphery, and by performing land / groove recording, desired data is recorded at a high density by effectively utilizing the information recording surface. be able to.

Since the address area is divided and the sector address by the land and the sector address by the groove are separately recorded, crosstalk due to the pit train can be effectively avoided.

(2) Second Embodiment FIG. 12 is a plan view showing an optical disc according to a second embodiment of the present invention in comparison with FIG. In the manufacturing process of the optical disk according to this embodiment, as in the first embodiment, a groove is formed, and the formation of the groove is interrupted at a predetermined angular interval to record address data using a pit string. At this time, in this embodiment, in the first half and the second half of the address area AR2, the address data of the sector by the following groove and the address data of the sector by the following land are recorded, respectively, and this pit row is tracked by the land. Place on the center.

According to the structure shown in FIG.
The same effect as that of the embodiment can be obtained.

(3) Third Embodiment FIG. 13 is a plan view showing an optical disc according to a third embodiment of the present invention in comparison with FIG. In the manufacturing process of the optical disk according to this embodiment, as in the first embodiment, a groove is formed, and the formation of the groove is interrupted at a predetermined angular interval to record address data using a pit string. At this time, in this embodiment, the address data of the sector by the following groove and the address data of the sector by the subsequent land are respectively recorded in the first half and the second half of the address area AR2. A pit row is formed on the boundary between the land and the groove, respectively.

According to the structure shown in FIG.
The same effect as that of the embodiment can be obtained.

(4) Fourth Embodiment FIG. 14 is a plan view showing an optical disc according to a fourth embodiment of the present invention in comparison with FIG. In the manufacturing process of the optical disc according to this embodiment, the grooves are formed sequentially so as to follow the groove on the outer circumference side when tracing the groove once, and further to follow the groove on the outer circumference when tracing this land once. Further, the formation of the groove is interrupted at a predetermined angular interval, and the address data based on the pit string is recorded. At this time, in this embodiment, the address area AR
In the first half and the second half of 2, address data of a sector by a subsequent groove and address data of a sector by a subsequent land are arranged on the corresponding track centers.

According to the configuration shown in FIG. 14, the same effect as that of the first embodiment can be obtained by applying the present invention to the case where land and groove are alternately connected to perform land / groove recording.

(5) Fifth Embodiment FIG. 15 is a plan view showing an optical disc according to a fifth embodiment of the present invention in comparison with FIG. In the manufacturing process of the optical disk according to this embodiment, the grooves are sequentially formed so as to follow the land on the outer circumference when the groove is traced once, and further follow the groove on the outer circumference when the land is traced once. Further, the formation of the groove is interrupted at a predetermined angular interval, and the address data based on the pit string is recorded. At this time, in this embodiment, address data is recorded in the first half and the second half of the address area AR2. At this time, each pit row is allocated to the boundary between the groove and the land, and is arranged so as to be offset between the first half and the second half.

According to the configuration shown in FIG. 15, the same effect as that of the first embodiment can be obtained by applying the present invention to the case where land and groove are alternately connected to perform land / groove recording.

(6) Sixth Embodiment FIG. 16 is a plan view showing an optical disc according to a sixth embodiment of the present invention in comparison with FIG. In the manufacturing process of the optical disk according to this embodiment, the grooves are sequentially formed so as to follow the land on the outer circumference when the groove is traced once, and further follow the groove on the outer circumference when the land is traced once. Further, the formation of the groove is interrupted at a predetermined angular interval, and the address data based on the pit string is recorded. At this time, in this embodiment, in the address area AR2, the address data of the pit row is arranged on the track center of each pit and land without being offset in the circumferential direction.

According to the configuration shown in FIG. 16, by arranging pit rows on the track center without offset in the circumferential direction and recording address data, the ratio occupied by address area AR2 can be reduced. it can. Thus, in addition to the effect according to the fifth embodiment, desired data can be recorded at a higher density. Further, by forming the pit train on the on-track, a reproduced signal of the pit train can be obtained with a high SN ratio, and the reliability can be improved accordingly. Further, since there is no need to switch the timing of address detection by the pit train depending on the track, the overall configuration can be simplified accordingly.

(7) Seventh Embodiment FIG. 17 is a plan view showing an optical disc according to a seventh embodiment of the present invention in comparison with FIG. In the manufacturing process of the optical disc according to this embodiment, tracks similar to those of the optical disc according to the first embodiment are formed, and the ZC
An address pit is formed in an AV shape. In the formation of the address pits, in the seventh embodiment,
The address data of the pit row is arranged on the track center of each pit and land without offset in the circumferential direction.

According to the structure shown in FIG. 17, when address pits are formed in a ZCAV shape, pit rows are arranged on the track center without offset in the circumferential direction, and address data is recorded. In addition to the effects of the first embodiment, the recording density can be further improved, and highly reliable address data can be detected with a simple configuration.

(8) Other Embodiments In the above-described embodiment, a case has been described in which 8 Kbytes of data are recorded in one address area AR2 using a pit string. However, the present invention is not limited to this. For example, data of 2K bytes, 4K bytes, or the like may be allocated.

In the above-described embodiment, the case where the same address data ID is repeatedly recorded twice has been described. However, the present invention is not limited to this, and it is not limited to this.
It may be repeated more than once or may be omitted.

Further, in the above-described embodiment, the case where the groove is meandered by the wobble signal without modulating the wobble signal has been described. However, the present invention is not limited to this, and various information can be obtained by the meandering of the groove. May be recorded together.

[0158]

Further, in the above-described embodiment, the case where the entire groove is meandered by the wobble signal has been described. However, the present invention is not limited to this. In the case where only one edge of the groove is meandered, and both edges are different wobble signals. It can be widely applied to meandering by a signal.

In the above embodiment, the case where desired data is recorded by land / groove recording has been described. However, the present invention is not limited to this, and can be widely applied to the case of groove / groove recording. In this case,
The depth of the grooves and pits is set to about 1/8 of the laser wavelength.

Further, in the above-described embodiment, the track pitch is 0.5 [μ] in land / groove recording.
m], the present invention is not limited to this. The present invention can be widely applied to the case where grooves are formed with a narrow track pitch. That is, the track pitch is set to 0.64 [μm] or less according to the setting of the track pitch and the linear recording density, and the redundancy of data to be recorded, and 8 [G
B] can be secured.

In the above embodiment, the case where the thickness of the light transmitting layer is set to 0.1 [mm] has been described. However, the present invention is not limited to this, and the thickness of the light transmitting layer is set to 177 mm.
[Μm] or less, and a capacity of 8 [GB] can be secured. Incidentally, it is necessary to ensure that the thickness of the light transmitting layer is 10 [μm].

In the above embodiment, the case where user data is recorded at a linear recording density of 0.21 [μm / bit] has been described. However, the present invention is not limited to this. μm / bit], and a capacity of 8 as in the above embodiment.
[GB] can be secured. When this is converted into a bit length and a mark length, the shortest bit length and the shortest mark length are within an allowable range of 0.3 [μm].

In the above embodiment, the wavelength 6
Although the case where desired data is recorded and reproduced by irradiating a laser beam of 50 [nm] with an optical system having a numerical aperture of 0.78 has been described, the present invention is not limited to this, and a desired numerical value is obtained by using an optical system having a high numerical aperture. It can be widely applied when recording data at high density. Considering the thickness of the light transmitting layer, the achievable working distance, and the like, a capacity of 8 GB can be ensured when the numerical aperture is 0.78 or more and the working distance is 560 μm or less.

In the above-described embodiment, the case where the present invention is applied to a recordable optical disk has been described. However, the present invention is not limited to this and can be applied to a read-only optical disk.

[0166]

As described above, according to the present invention, the meandering of the groove is interrupted at a predetermined angular interval to record the address data by the pit train, so that the desired data is recorded in each sector by the pit train. In this case, even when the address data cannot be correctly reproduced due to dust or the like, each sector can be correctly accessed by the interpolation processing based on the meandering of the groove. Therefore, in the address data, even when information is recorded at a high density, the redundancy can be set low, and the address recorded on the optical disk can be reliably detected by effectively utilizing the information recording surface. it can.

[Brief description of the drawings]

FIG. 1 is a plan view for describing zoning by a mastering device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a mastering device applied to the zoning of FIG. 1;

FIG. 3 is a schematic diagram illustrating a configuration of a sector by zoning in FIG. 1;

FIG. 4 is a perspective view showing an optical disc generated by the mastering device of FIG. 1;

FIG. 5 is a block diagram illustrating an optical disk device that accesses an optical disk manufactured by applying the mastering device of FIG. 1;

FIG. 6 is a schematic diagram illustrating an optical head of the optical disk device of FIG. 5;

FIG. 7 is a cross-sectional view showing a configuration around an objective lens of the optical head of FIG. 6;

FIG. 8 is a block diagram showing a data processing system of the optical disk device of FIG.

FIG. 9 is a table provided for explaining a sector structure in the optical disc device of FIG. 8;

FIG. 10 is a table showing ECC blocks in the optical disk device of FIG. 8;

FIG. 11 is a table for explaining a frame structure in the optical disc device of FIG. 8;

FIG. 12 is a plan view for explaining sectors by a mastering device according to a second embodiment of the present invention.

FIG. 13 is a plan view for explaining a sector by a mastering device according to a third embodiment of the present invention.

FIG. 14 is a plan view for explaining a sector by a mastering device according to a fourth embodiment of the present invention.

FIG. 15 is a plan view for explaining sectors by a mastering device according to a fifth embodiment of the present invention.

FIG. 16 is a plan view for explaining sectors by a mastering device according to a sixth embodiment of the present invention.

FIG. 17 is a plan view for explaining a sector by a mastering device according to a seventh embodiment of the present invention.

[Explanation of symbols]

1 ... mastering device, 2 ... master disk, 5 ...
Drive circuit, 6 ... Address signal generation circuit, 7 ... Wobble signal generation circuit, 10 ... Optical disk drive, 11 ...
Optical head, 12 optical disk, 35 PLL circuit,
37: an address detection circuit, 39: a wobble signal processing circuit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B ^7/ 00-7/24

Claims (2)

(57) [Claims] 1. A method of recording desired data on the information recording surface by a land-groove recording method using a laser beam applied to the information recording surface through a light transmitting layer having a thickness of 10 to 177 [μm], or An optical disc adapted to reproduce data recorded on the information recording surface, wherein the information recording surface is radially divided by a predetermined angular interval, and a recording region of user data and a recording of address data are arranged in a circumferential direction. In the user data recording area, the track pitch by the groove is 0.64 [μm] or less, and the width of the groove is substantially equal to the width of the land. The meandering groove is formed in a spiral shape, and the track by the groove and the track by the land are formed side by side in a spiral shape. In the data recording area, the formation of the groove is stopped, the address data recording area is divided into a laser beam scanning start area and a scan end side area, and in the user data recording area, The meandering of the groove converted into the rotation angle of the optical disc is within a predetermined range, so that the adjacent grooves have the same phase, so that the meandering of the groove is formed according to a sine wave signal of a single frequency, In an area on the scanning start side of the laser beam, only for the track by the groove or the land, a pit row is formed on the track center and address data is recorded. In an area on the scanning end side of the laser beam, the land or A pit row is formed on the track center only for the track by the groove, and the address data is An optical disc characterized by having recorded thereon. 2. The optical disk according to claim 1, wherein the address data is formed by data for synchronization of a PLL circuit, a sector mark, an address mark, time information or position information, and an error detection code.