JPH10320827A - Optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively utilize the peculiar functions of an optical disk device and to secure the storage capacity, in which operability that is comparable to a video tape recorder is obtained, by recording the desired user data by irradiating the laser beams having a wavelength less than a specific value by the optical system having the working distance less than a specific value and the numerical aperture more than a specific value. SOLUTION: Each focal distance and each interval are set so that the numerical aperture of an objective lens 17, which consists of a first lens 17A and a second lens 17B, becomes more than 0.7. An optical head secures an approximately 8 GB storage capacity by irradiating an optical disk 12 with the laser beams having the wavelength of less than 680 mm through the optical system having the numerical aperture of more than 0.7. At that time, a working distance WD is set to less than 560 μm and the mass-production of the heads are made possible. Thus, the video recording time and the operability comparable to a video tape recorder are obtained and the editing, which effectively uses the random access function of the optical disk device, is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device, and can be applied to, for example, an optical disk device for compressing and recording a video signal and an audio signal. The present invention has a working distance of 560 [μm].
By using an optical system having a numerical aperture NA of 0.7 or more and irradiating a laser beam having a wavelength λ of 680 [nm] or less to access the optical disk, the functions unique to the optical disk device are effectively utilized. A recording capacity that is as large as possible and that can obtain the same usability as a video tape recorder can be secured.

[0002]

2. Description of the Related Art Conventionally, a DVD (Digital Versatile Disc) has been proposed as an optical disk device for recording information at high density. In this DVD, a laser beam having a wavelength of 650 [nm] is irradiated onto an optical disc by an optical system having a numerical aperture of 0.6, so that data of 2.6 [MB] can be recorded on one side. One hour of video signal can be recorded.

[0003] This DVD is a CD (Compact D)
It is formed in the same shape and size as isc), so that a user who is accustomed to the simplicity and usability of the CD can accept the CD without discomfort.

Further, it is considered that the operation mode can be switched at a high speed by effectively utilizing the access function peculiar to the optical disk device, and further, it is considered that the operations such as trick play and editing can be easily performed. I have.

[0005]

By the way, 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. Must be recordable. In addition, in order to enable processing such as editing by effectively utilizing a random access function or the like which is a feature of an optical disk, it is necessary to record a video signal for about 3 hours. In this case, referring to the DVD system, 8
It is necessary to record data of about [GB].

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has a recording capacity that can effectively utilize the functions specific to an optical disk device and that can obtain the same usability as a video tape recorder. It is intended to propose an optical disk device that can be secured.

[0007]

According to the present invention, a working distance 560 is provided.
A desired user data is recorded by irradiating a laser beam having a wavelength λ of 680 [nm] or less with an optical system having a numerical aperture NA of 0.7 or more set to [μm] or less.

At this time, when the shortest pit length or the shortest mark length is 0.3 μm or less, or the linear recording density is 0.23 μm or less.
[Μm / bit] The following is recorded.

At this time, the track pitch is set to 0.6 [μ
m] is set as follows.

[0010] The data transfer rate of user data at the time of recording on the optical disk and at the time of reproducing from the optical disk is set to 11.08 [Mbps] or more.

At this time, redundant data is added and recorded with a redundancy of 23% or less.

When the thickness variation of the light transmitting layer is Δt, the numerical aperture NA and the wavelength λ are Δt ≦ ± 5.26 ×
(Λ / NA ⁴ ) [μm] is satisfied.

Further, the optical disk is stored and held in a predetermined cartridge, and the optical disk stored in the cartridge is rotated to access.

The meandering of the groove serving as the guide groove of the laser beam is changed stepwise in order, and the rotation speed of the optical disc is sequentially changed stepwise in accordance with the meandering cycle.

Further, based on the address information recorded on the track, one round of the track is divided into a plurality of sectors, and user data is recorded on a sector basis.

Further, user data is recorded in the groove and the land.

Further, when recording on an optical disk or reproducing from the optical disk and inputting the data to a buffer memory,
The data transfer speed of the user data is increased compared to the data transfer speed input to the buffer memory or the data transfer speed output from the buffer memory.

Further, user data is divided into blocks in predetermined blocks, an error correction code is added thereto, and recording / reproducing is performed on the optical disk in units of the blocks, and the unit of the block is set to 32 KB or more.

With an optical system having a numerical aperture NA of 0.7 or more,
By irradiating a laser beam having a wavelength λ of 680 [nm] or less to record desired user data, high-density recording can be performed with a spot size of about １ ／ compared to DVD. As a result, PRML (Partial-Response Max
The recording capacity can be set to about 8 [GB] by combining imum-likelihood, etc., or by reducing redundancy by adopting an efficient premastered address. At this time, if the working distance is set small, an optical system can be formed with a small-diameter lens even at a high numerical aperture of 0.7 or more, and the lens curvature, the eccentricity tolerance between lens surfaces, and the surface angle tolerance are practically used. It can be set to a sufficient range. In this case, if the working distance is set to 560 [μm] or less, a laser beam can be incident on the objective lens with a beam diameter of 4.5 [mm] or less, which is close to the current practical limit of DVD. .

At this time, the DVD has a minimum pit length of 0.4 [μ
m], this is simply converted to the shortest pit length or shortest mark length 0.3 [μm] by the numerical aperture. As a result, the shortest pit length or shortest mark length 0.3
[Μm] or less, the same margin as that of the DVD can be secured, and a capacity of 8 [GB] can be secured. When (1, 7) RLL modulation is applied to this, the linear density becomes 0.23 [μm / bit], and PRML is further increased.
By applying the above, a linear density of 0.23 [μm / bit] or less can be achieved. As a result, recording is performed at 0.23 [μm / bit] and the same margin as that of DVD is secured.
[GB] capacity can be secured.

When the track pitch is calculated from these relationships, the track pitch is set to 0.6 [μm] and the DV
By securing the same margin as D, a capacity of 8 [GB] can be secured.

Further, the data transfer rate is set to 11.08 [Mb
ps] or more, a sufficient time for seeking etc. is secured even when recording an audio signal multiplexed with a video signal compressed by MPEG2, which requires a rate of 6 [Mbps] or more for the image. Continuous video signal can be recorded and reproduced.

At this time, redundant data is added and redundancy 2
By recording at less than 3%, user data can be recorded efficiently.

When an optical disk is accessed by an optical system having a high numerical aperture, the skew margin of the optical disk is reduced, which can be compensated for by reducing the thickness of the light transmitting layer. At this time, Δt ≦ ± 5.26 × (λ / NA ⁴ ) [μ
m] so that the optical disc can be accessed stably. Further, in this case, dust having a size of 100 [μm] or more appears as a burst error due to the influence of dust and scratches on the disk surface. The effect can be reduced.

If the meandering of the groove is changed in a stepwise manner, and the rotation speed of the optical disk is changed in a stepwise manner in accordance with the meandering cycle, the so-called ZC is obtained.
By accessing the optical disk by means of LV (Zoned Constant Linear Velocity), it is possible to efficiently use the information recording surface of the optical disk to record desired data and to effectively avoid a decrease in access speed.

If one round of the track is divided into a plurality of sectors and user data is recorded in units of the sectors, the access speed can be improved by adopting the sector structure.

By recording data on both lands and grooves, an optical disk having a narrow track pitch can be easily manufactured, and a tracking error signal can be detected with a sufficient SN ratio.

The data transfer speed of user data when recording on an optical disk or reproducing from an optical disk and inputting the data to a buffer memory is determined by the data transfer speed input to the buffer memory or the data transfer speed output from the buffer memory. If the speed is made higher than the speed, it is possible to execute a process for replacing a defective sector, and to realize functions such as simultaneous recording / reproduction and after-recording.

Further, error correction processing can be performed with a block size of 32 KB or more to enhance error correction capability.

[0030]

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.

Here, 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 rotated by a spindle motor 3 at a constant angular velocity.

The optical head 4 irradiates the laser beam L to the disk master 2 while sequentially displacing the disk master 2 from the inner circumference to the outer circumference 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 thread 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 on the optical disc prepared from the master disc 2 at a linear recording density of about 0.21 [μm / bit]. Data of a capacity of 8 GB or more can be recorded on this optical disc.

[0035]

(Equation 1)

Here, the numeral 4.7 is the recording capacity [GB] of the DVD, which is 0.74 and 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 exposure to the laser beam L and the width of the land between adjacent grooves are substantially equal. 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. As a result, the optical head 4 can
The master disc 2 is exposed so that the optical disc created by the above-mentioned method can record land and groove.

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. 3, the description of the grooves and pits is simplified.

That is, in the mastering apparatus 1, in an optical disk having a diameter of 120 [mm] equal to that of a compact disk, an area having a radius of 24 [mm] to 58 [mm] is sequentially set on the disk master 2 so as to set an area for information recording. Form a track. 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 this switching stepwise from the inner circumference side to the outer circumference side in a stepwise manner, the information recording surface is concentrically divided to form 14 zones Z0 to Zn.

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 indicated by arrows A and B, showing the boundaries of the sector in an enlarged manner.
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, in the first half of the address area AR2, the displacement of the irradiation position of the laser beam is stopped, and the light amount of the laser beam is intermittently raised by the drive signal SD. 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 to 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 string, and the second half of the address area AR2. Address data of a sector by a land on the peripheral side is recorded in a pit row on a corresponding track center.

At this time, when the optical disk is prepared from the master disk 2, the drive circuit 5 has a wavelength of 650 [nm].
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 disk master 2 as a wobble signal WB. At this time, the wobble signal generation circuit 7 sequentially increases the frequency of the wobble signal WB and outputs it 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 the groove for 397 periods 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 to meander for 3573 periods.
The groove is formed so that the meandering of the groove is sequentially increased by 397 cycles per track as the zone moves to the outer peripheral zone. In this embodiment, one of the groove meanders is used.
25 bytes of data are stored in user area A
R1 is assigned to R1, and one cycle is formed by 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. 4 (FIGS. 4A and 4C).
1) and (C2)). The numbers shown in FIG. 4 are the number of bytes of each data.

The address signal generating 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. 4 (B), (C1) and (C2)). Here, the address signal generation circuit 6 forms each sector header by 62 bytes, and forms data to be recorded in the address area AR2 by 8 Kbytes. The sector mark SM is
Set to indicate the start of the sector header, 4 bytes are allocated. The timing data VFO for synchronization is
It is arranged to lock the 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 generation circuit 6 converts the sector header generated in this way 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.

Thus, the optical disk produced from the master disk 2 is preformatted such that the information recording surface is divided concentrically and the number of sectors increases sequentially 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. 4)
(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 guard of 52 bytes, and a buffer of 16 bytes are sequentially allocated.

Here, the gap is a land-groove switching region and a laser beam intensity switching region, 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. 5 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 surface for transmitting the laser beam and guiding the laser beam to the information recording surface is formed on the information recording surface with a thickness of about 0.1 [mm]. Thus, even if the optical disk according to this embodiment is irradiated with a laser beam from a high numerical aperture optical system via a light transmitting surface, the effect of skew is effectively avoided and desired data is stored on this information recording surface. 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 housed 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 able 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.

Thus, in the case of a phase-change type optical disk, the optical disk is formed so that the crystal structure of the information recording surface is locally changed by laser beam irradiation so that desired data can be recorded. 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 position irradiated with a laser beam so that desired data can be thermomagnetically recorded. Further, by detecting a polarization plane of return light, a magnetic Kerr effect is utilized. 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 disc, in each zone, the disc master 2 is rotationally driven under the condition of a constant angular velocity, and the frequency of the wobble signal is switched step by step, and a groove is formed by the wobble signal WB. Will be. 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.

Further, in this embodiment, two types of optical discs, one having an information recording surface formed on one side only and one having an information recording surface formed on both sides, are manufactured. The optical disc with the surface formed is
When an optical disk having a thin disk substrate is bonded, the thickness is 1.2 mm, and the thickness of each light transmitting layer is 0.1 mm.
[Mm].

FIG. 6 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 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.

When the optical disk 12 is a write-once optical disk, the laser beam irradiation position is locally destroyed to record desired data, and the recorded data can be reproduced according to the 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 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. 8 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 is formed to have a relatively large diameter, whereas the first lens 17A on the optical disk 12 is small. 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.

[0079]

(Equation 2)

[0080]

(Equation 3)

The equation (2) shows the relationship between the skew margin θ for stably accessing the optical disc and the optical system (Japanese Patent Laid-Open No. Hei 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.

In this way, 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.

[0084]

(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, as shown in FIG. 9, assuming that a laser beam having the same beam diameter is incident and the numerical aperture is increased, it is necessary to dispose the objective lens closer to the information recording surface of the optical disk. In FIG. 9, the working distance is shown assuming that the thickness of the light transmitting layer is 0. 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 lens surface of the first lens 17A on the optical disk 12 side is formed flat so that focus control can be reliably performed. Has been made.

Further, the objective lens 17 is
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
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. 6), the spindle motor 33 drives the optical disk 12 to rotate under the control of the system control circuit 34. At this time, in the normal operation mode, the spindle motor 33
The write / read clock R / generated by the L circuit 35
By rotating the optical disc 12 so that WCK has a constant frequency, the optical disc 12 is rotationally driven by a so-called ZCLV (Zone Constant Liner Velocity) technique as shown in FIG. Here, this ZC
The zoning by the LV corresponds to the zoning described with reference to FIG.

That is, the spindle motor 33 sequentially drives the optical disc 1 in accordance with the laser beam irradiation position.
2 is switched (FIG. 10 (A)), thereby improving the recording density of the optical disc device 10 by preventing the linear velocity and the linear recording density from changing significantly between the inner peripheral side and the outer peripheral side (FIG. 10A). (B) and (C)), and a reduction in access speed is effectively avoided.

On the other hand, in a special operation mode such as post-recording, the spindle motor 33 controls the optical disk 12 at a predetermined rotation speed under the control of the system control circuit 34.
Is driven to rotate.

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 from the optical head 11 a reproduction signal RF whose signal level changes in accordance with the amount of return light, 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 the error detection code assigned to each address data ID, and selectively selects the 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 divider 35B. Here, the frequency divider 35B
In, the frequency division ratio is switched according to the setting of the system control circuit to output a predetermined clock CK.

Thus, 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 frequency-divided by the frequency divider 35B, so that a highly accurate clock CK can be generated.

In the PLL circuit 35, the frequency divider 35
B is set by the system control circuit 34 so as to correspond to the zoning explained with reference to FIG. Thus, the PLL circuit 35 increases the frequency of the oscillation output of the voltage-controlled oscillation circuit 36D with respect to the frequency of the wobble signal WB in a stepwise manner as the laser beam irradiation position is displaced toward the outer peripheral side of the optical disc 12. The oscillation output is written to the write / read clock R / W CK
Output as

In the optical disk apparatus 10, in the normal operation mode, the optical disk 12 is rotated by the spindle motor 33 so that the write / read clock R / W CK has a constant frequency. By recording desired data on the basis of WCK, the linear recording density is not largely changed between the inner peripheral side and the outer peripheral side, and the recording density can be increased accordingly.

The cluster counter 38 counts the write / read clock R / W CK on the basis of 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 processing, 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 divider 35B according to the frequency division ratio data stored in the memory 42 in accordance with the laser beam irradiation position based on the address data ID. .

Thus, in the normal operation mode, the system control circuit 34 operates in the zone Z described with reference to FIG.
0, Z1,..., Zn-1, and Zn, the rotation speed of the optical disk is gradually reduced stepwise from the inner peripheral side toward the outer peripheral zone so as to correspond to the inner peripheral zone and the outer peripheral zone. Each sector is set to the same recording density with the zone on the side.

On the other hand, in special operation modes such as post-recording, user data DU1 and DU of two channels
In the case where the recording / reproducing process is alternately repeated for No. 2 or when the user data DU1 and DU2 of two channels are alternately reproduced from the optical disc 12 and output simultaneously and in parallel, the system control circuit 34 The operation of the spindle servo circuit is controlled so that the rotation speed of the optical disk 12 is not switched even if the zone is switched for reproduction.

Thus, when the recording / reproducing process is alternately repeated, the system control circuit 34 performs
Even if the zone is switched, the user data DU is reproduced at the rotation speed of the optical disk 12 at the time of the immediately preceding recording. Also, user data DU1 and DU2 of two channels
Are alternately reproduced from the optical disk 12 and output simultaneously and in parallel, for one piece of user data, the optical disk
2 is played back from the optical disk 12 while being rotated.
In these cases, the system control circuit 34 determines that the recording side channel and the other reproduction side channel have Z
By applying the CLV method, the optical disc 12 is driven to rotate at a rotation speed twice as high as the rotation speed set for each corresponding zone to record and reproduce user data.

In this type of optical disk device, when the rotation speed of the optical disk is switched,
It takes time to settle. As a result, in the optical disk device 10, the time required for switching the rotation speed of the optical disk 12 is omitted, and recording / reproduction is performed only by the waiting time required for locking the PLL circuit, which is much shorter than the rotation speed switching. Operation is switched.

At this time, the system control circuit 34 sets the rotation speed of the optical disc 12 to about twice the rotation speed in the normal operation mode in the control of the ZCLV applied to the recording channel and the other reproduction channel. . As a result, the system control circuit 34 intermittently records and reproduces the user data DU on the optical disc 12 at a high speed and intermittently when processing the two-channel user data, thereby performing seek and other processing. You have enough time to make sure.

FIG. 11 is a flowchart showing a process of setting the rotation speed of the optical disk in the system control circuit 34. When the user selects the operation mode, the system control circuit 34 proceeds from step SP1 to step SP1.
The process proceeds to step 2, where it is determined whether or not the operation mode selected by the user is the above-described operation mode such as after-recording. If a negative result is obtained here, the process proceeds to step SP3. Here, the system control circuit 34 sets the operation mode of the spindle servo circuit to the operation mode based on ZCLV, and then proceeds to step SP4 and ends this processing procedure.

On the other hand, if the operation mode selected by the user is the above-mentioned operation mode such as after-recording, a positive result is obtained in step SP2, and the system control circuit 34 proceeds to step SP5. Here, for example, when recording and reproducing two channels, respectively, the system control circuit 34 performs
When reproducing two channels, the switching of the rotation speed is stopped for any one of the channels (that is, the operation mode is set to CAV). Subsequently, the system control circuit 34 proceeds to step SP6, and for the remaining channels, the ZCL at the above-described rotation speed.
After the operation mode based on V is set to the spindle control, the process proceeds to step SP4, and this processing procedure ends.

The system control circuit 34 controls the writing and reading in accordance with the cluster start pulse output from the cluster counter 38 while controlling the rotation speed of the optical disk 12 in this manner, so that the address set in each sector is controlled. One cluster of data is assigned to four consecutive sectors based on the area AR2. 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. Switching control is performed between and.
Thus, the optical disk device 10 can perform so-called land / groove recording.

FIG. 1 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 converting the video signal and the audio signal from analog to digital,
Data is compressed according to a format prescribed by MPEG (Moving Picture Experts Group). Further encoder 5
1 packetizes the data-compressed video signal and audio signal, and adds a packet header, control data, and the like to each packet. The encoder 51 sequentially multiplexes the data-compressed video signal and the audio signal by sequentially outputting these packets,
The user data DU is generated by the time-division multiplexed bit stream.

In this series of processing, the encoder 51
Can simultaneously and simultaneously process two-channel video and audio signals and output two-channel user data DU1 and DU2 corresponding to the two-channel video and audio signals simultaneously and in parallel. Under the control of the system control circuit 34, these two channels are simultaneously processed in parallel if necessary.

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 in 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 decoder 52, like the encoder 51, is configured to be able to execute such decoding processing simultaneously and in parallel on up to two channels of video and audio signals SOUT1 and SOUT2.
The operation is switched under the control of the system control circuit 34 to execute the two-channel simultaneous parallel processing as necessary.

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. 12, 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.

As shown in FIG. 13, 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. 14, and allocates this one cluster to four consecutive sectors.

Thus, the recording / reproducing circuit 53 sets the redundancy to 23% or less when adding the redundant data such as the frame synchronization signal, the error correction code, and the frame address to the user data. Set and record user data efficiently. As described above, in the DVD, the redundancy is set to 23 [%]. In this embodiment, even if the redundancy is set to be equal to that of the DVD, a sufficient recording capacity can be secured. Incidentally, even if the redundancy is set to 23% or more, the error correction capability is unnecessarily enhanced.

The ECC data block is set to 32 [K
B), it is possible to secure a sufficient inter-code interval in the error correction processing, and thereby to enhance the error correction capability. Further, the recording and reproduction processing is executed in units of ECC data blocks, so that the recording and reproduction processing as well as the post-recording and other processing can be executed by simple processing as a whole.

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. Further, at the time of this output, by operating based on the write / read clock R / WCK, in a normal operation mode, the data is output at a data transfer rate of 11.08 [Mbps] in terms of user data DU. As a result, the data is output intermittently at a higher transfer rate than the user data DU input from the encoder 51. Thereby, the recording / reproducing circuit 53
The optical head 11 can be sought using the remaining time for recording the user data DU intermittently, and continuous user data can be discretely recorded by the seek.

Further, in a special operation mode such as post-recording or the like, the user data DU is converted to about 20 [Mbp].
s], and outputs data modulated by the data transfer rate.
This allows the user data DU1 and DU2 of two channels to be recorded alternately as needed. In this way, by repeating the recording and reproducing operation in units of clusters, the optical disk device 10 reproduces data recorded on the optical disk 12, edits and records the reproduced data, and further performs post-recording and the like. Processing can be performed.

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 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.

At this time, the recording / reproducing circuit 53
(Patial-Response Maximum-Likelihood) is applied to decode the reproduced data to generate decoded data. Further, the recording / reproducing circuit 53 performs a deinterleave process on the decoded data, performs an error correction process, and
Output to 2.

Thus, in DVD, (1, 1,
7) The RLL-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 ], Desired data can be recorded and reproduced. On the other hand, if the intersymbol interference is positively utilized by PRML, the line recording density of 0.23 [μ
m] A similar margin can be secured as follows.

At this time, in the normal operation mode, the recording / reproducing circuit 53 outputs the user data DU in the same manner as during recording.
The data is intermittently reproduced from the optical disk 12 in clusters at a data transfer rate of 11.08 [Mbps], and the reproduced user data DU is continuously output to the decoder 52 via the memory 54. . On the other hand, in a special operation mode such as post-recording, the user data DU corresponding to the rotation speed of the optical disc 12 is recorded.
The data is intermittently reproduced from the optical disk 12 in units of clusters at a data transfer rate of about 20 [Mbps], and the reproduced user data DU is stored in the memory 5.
4 to the decoder 52 continuously.

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. 12) 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 output. Is analyzed and notified to the system control circuit 34.

The memory 54 is composed of a large-capacity buffer memory for temporarily storing and holding user data.
A write pointer in a memory control circuit (not shown),
By the address control by the read pointer, the recording area is sequentially and cyclically switched, and the user data DU is continuously input / output between the encoder 51 and the decoder 52.
The user data DU is intermittently input / output to / from the optical disk 12 via the recording / reproducing circuit 53 in cluster units.

At this time, the memory 54 stores the two-channel user data D in the special operation mode such as post-recording.
When U1 and DU2 are simultaneously processed in parallel, as shown in FIG.
1 and DU2, input / output pointers P1H and P2H for the optical disk 12 and input / output pointers P1O and P2O for the encoder 51 and the decoder 52 are set, and the encoder 51 and the decoder 52 are controlled by address control using these pointers. , These two channels of user data DU1 and DU2 are input and output simultaneously in parallel and continuously, and with respect to the optical disk 12, the user data DU1 and DU2 are input and output alternately in cluster units. I do.

FIG. 15 shows the setting of pointers in the case of after-recording, and the input / output pointers P1H and P2H for the optical disk 12 are read and write pointers RPw and RPw for the optical disk 12, respectively.
WPr, and pointers P1O and P2O for input / output to the encoder 51 and the decoder 52 are a pointer WPw for input from the encoder 51 and a decoder 52, respectively.
2 shows a pointer RPr for output to.

As described above, if the capacity of the memory 54 is set to about 10 [Mbit], the data transfer rate to the encoder 51 and the decoder 52 becomes 8 [Mbps],
Assuming that the time required for the seek is about 200 [msec], the user data of two channels is alternately recorded and reproduced on the optical disc 12 at intervals of about 2 seconds without interrupting the video signal and the audio signal by the user data. It can be recorded and reproduced.

At the time of 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. Thereby, the optical disk device 10
In this example, a mark row having a maximum run length of 8T and a minimum run length of 2T is formed by the shortest recording marks 4/3 bits, and user data is recorded at a linear recording density of 0.21 [μm / bit].

When the optical disk 12 is of the phase change type or the write-once type during writing, the laser drive circuit 57 intermittently sets the light amount of the laser beam based on the output data of the recording / reproducing circuit 53 under the control of the system control circuit. And the user data DU is recorded on the optical disk 12. As a result, in the optical disc device 10, a mark row or pit row having a maximum run length of 8T and a minimum run length of 2T is formed by the shortest recording mark or the shortest recording pit of 4/3 bits, and the linear recording density is 0.21 [μm / bi.
t], and the shortest mark length or shortest pit length 0.3
[Μm] User data is recorded as follows.

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

The modulation coil drive 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.
As a result, the modulation coil drive circuit 56 applies a modulation magnetic field to the laser beam irradiation position where the light amount rises intermittently, and applies the thermomagnetic recording method to obtain the shortest recording mark 4 /.
A mark having a maximum run length of 8T and a minimum run length of 2T is formed by 3 bits, and a linear recording density of 0.21 [μm /
bit] and the shortest mark length of 0.3 [μm] or less.

FIG. 16 is a chart showing the control of the system control circuit 34 during normal recording and reproduction. In the following description, writing and reading to and from the optical disk 12 are indicated by reference numerals R and W in the drawings. During recording, the system control circuit 34 sequentially inputs 1
The channel video signal and audio signal SIN (FIG. 16A) are converted into user data DU by the encoder 51 and sequentially input to the memory 54. Further, while the optical head 11 seeks to a target sector and keeps it still, the data amount of a predetermined recording unit is accumulated in the memory 54, and when the free space of the memory 54 becomes equal to or less than a predetermined value, the cluster is set as a unit. The user data DU stored in the memory 54 is recorded on the optical disc 12 (see FIG. 1).
6 (B) and (C1)).

When the amount of user data held in the memory 54 becomes equal to or smaller than a predetermined value by the recording process on the optical disc 12, the system control circuit 34
Suspend the recording for 2. The system control circuit 34
The optical head 11 is kept in a still state with respect to the succeeding sector, and waits until the data amount of the recording unit is accumulated in the memory 54 again. When the data amount of the recording unit is accumulated in the memory 54, It is recorded on the optical disk 12 again (FIG. 16
(B) and (C2)).

Thus, the system control circuit 34 intermittently compresses the user data DU via the memory 54 on the time axis and records continuous user data DU to continuous sectors. The system control circuit 34
Is determined based on the file management data recorded in the lead-in area of the optical disc 12, and if a continuous area cannot be secured on the optical disc 12, the user data DU is recorded discretely. D
When U is recorded on the optical disk 12, not only the still but also the seek process is executed, and the rotation speed of the optical disk 12 is switched as needed.

On the other hand, if the user selects the reproduction process, the system control circuit 34 instructs the optical head 11 to seek to the target sector and then starts reproduction. The stored user data DU is stored in the memory 54, and the user data DU stored in the memory 54 is sequentially output to the decoder 52. In this state, when the data amount of the user data DU stored in the memory 54 becomes a predetermined recording and reproducing unit and the free space of the memory 54 becomes equal to or less than a predetermined value, the system control circuit 34
The optical head 11 is held still with respect to the subsequent sector, and the reproduction of the user data DU from the optical disk 12 is interrupted.

In this state, when the amount of data held in the memory 54 falls below a predetermined value, the system control circuit 34
An instruction to start reproduction of the optical disk 12 is issued. As a result, the system control circuit 34 intermittently reproduces the user data DU from the optical disc 12 and outputs continuous video and audio signals SOUT without interruption.

FIG. 17 is a schematic diagram showing a case where the user selects the chase playback mode. This chasing playback is set, for example, when recording the video signal and the audio signal specified by the user and the user instructs the playback of the program being recorded from the recording start position while maintaining the recording mode. .

When the user selects this operation mode while the one-channel video signal and the audio signal are being recorded on the optical disk 12 as described with reference to FIG.
2 is switched to twice the normal rotation speed. In synchronization with this, the write / read clock R / WC
The frequency division ratio of the frequency divider 35B is set so that K is usually twice the frequency (FIG. 6). Thereby, the system control circuit 3
4 increases the data transfer speed to the optical disk 12 almost twice as much as before, and records the user data DU intermittently on the optical disk 12. In this case, it is also possible to operate at twice the speed from the beginning.

In addition to switching the data transfer speed in this way, the system control circuit 34 uses the idle time during the recording of the user data DU by setting the four pointers described above with reference to FIG. The reproduced user data is reproduced (FIG. 17A)
(B) and (C)). That is, the system control circuit 34
When the user data DU stored in the memory 54 is recorded on the optical disk 12 and the amount of user data for recording stored in the memory 54 falls below a predetermined value, the optical disk 1
2 is interrupted, and the optical head 11 is moved to the recording start position.
Is sought (FIG. 17 (D1)).

Subsequently, the system control circuit 34 starts reproducing the user data DU from this recording start position (FIG. 1).
7 (D2)), the user data DU reproduced from the optical disk 12 is sequentially stored in the memory 54, and the user data DU stored in the memory 54 is output to the decoder 52. At this time, a predetermined amount of user data DU is stored in the memory 54, and when the amount of recording-side user data held in the memory 54 becomes equal to or less than a predetermined value, the decoder 52
The reproduction from the optical disk 12 is interrupted while the output of the user data DU to the.

Further, the system control circuit 34 makes the optical head 11 seek (FIG. 17D3),
While the user data DU is being reproduced, the memory 54
The user data DU stored in the sector is recorded subsequently to the interrupted sector (FIG. 17 (D4)).

When the amount of user data on the recording side stored in the memory 54 exceeds a predetermined value and the amount of user data reproduced from the optical disk 12 and held in the memory 54 becomes equal to or less than a predetermined value, the system control circuit 34 sets The recording process is interrupted, the optical head 11 is sought again, and the subsequent user data is reproduced.

Thus, the system control circuit 34 continuously reproduces and outputs the video and audio signals recorded on the optical disc 12 while recording the continuous video and audio signals on the optical disc 12.

In recording and reproducing the two-channel user data in this manner, the system control circuit 34
As shown in FIG. 18, when the zone to be recorded is switched from, for example, Zm to Zm + 1, the rotation speed of the optical disc 12 is maintained at twice the normal rotation speed. The optical disc 12 corresponds to the rotation speed of each zone at a normal rotation speed serving as a reference.
Are switched (FIGS. 18A and 18B).
This allows the system control circuit 34 to write and read clock R
/ WCK is maintained at a constant frequency, and accordingly, the linear velocity at the laser beam irradiation position is also maintained substantially constant (FIGS. 18C and 18D).

On the other hand, at the time of reproduction, switching of the rotation speed of the optical disk 12 is interrupted, and the optical disk 12 is reproduced while maintaining the rotation speed at the time of the immediately preceding recording. In this case, in the recording / reproducing circuit 53, a reproduction clock is obtained by a frequency corresponding to the rotation speed of the optical disk 12, and the reproduction clock is used by the reproduction clock.
The obtained reproduction data is processed. Since the reproduced clock corresponds to the write / read clock R / W CK generated by the PLL circuit 35, in this case, the read / write clock R / W CK is used.
Will change in accordance with the laser beam irradiation position.

As a result, the system control circuit 34 reduces the frequency of switching the rotation speed of the optical disk 12, thereby improving the access speed.

FIG. 19 is a schematic diagram showing a case where the user selects the multi-channel mode. Here, the multi-channel is a process of simultaneously recording or reproducing two-channel video and audio signals. In this case, the system control circuit 34 sets the rotation speed of the optical disc 12 to twice the normal rotation speed, and records or reproduces two-channel video and audio signals.

When the user selects the multi-channel recording mode, the system control circuit 34 processes the two-channel video and audio signals by the encoder 51 and generates two-channel continuous user data DU1 and DU2. , This user data DU1,
DU2 is sequentially input to the memory 54 (FIGS. 19A and 19B).

Further, the system control circuit 34 seeks the optical head 11 at a predetermined recording start position and waits by setting the four pointers described above with reference to FIG. 15 (FIGS. 19C and 19D). When any user data DU1 or DU2 is stored in the memory 54 by a predetermined amount, recording of the user data DU1 or DU2 on the optical disc 12 is started (FIG. 19 (D)).
2)). As a result, when the data amount of the user data whose recording has started in the memory 54 becomes equal to or less than a predetermined value, the recording on the optical disk 12 is interrupted. Further, the system control circuit 34 causes the optical head 11 to seek to the recording start position of another channel and waits (see FIG.
3)) and the user data DU held in the memory 54 for the other channels is similarly recorded (FIG. 19 (D)
4)).

The system control circuit 34 alternately repeats this series of processing, thereby recording successive two channels of user data on the optical disc 12 alternately while inputting them to the memory 54. At this time, the system control circuit 3
Reference numeral 4 preliminarily grasps the recording times of the two video signals and audio signals in accordance with the user's input and the like, secures a continuous area in each channel in advance, and causes the optical head 11 to seek.

On the other hand, if the user selects the multi-channel reproduction mode, the system control circuit 34 seeks the optical head 11 and controls access to the optical disk 12 as in the case of recording. The user data of two channels is intermittently reproduced from the optical disk 12 and stored in the memory 54, and the user data of two channels stored in the memory 54 is continuously decoded by the decoder 52 and output.

In this multi-channel reproduction mode, the system control circuit 34 maintains the rotation speed of the optical disc 12 at the rotation speed of the other channel for one of the channels. The access speed is improved by reducing the switching frequency.

FIG. 20 is a schematic diagram showing a case where the user has selected a post-recording mode. In this case, in the optical disk device 10, as shown in FIG. 21, the sequentially reproduced video signal and audio signal (FIG. 20A) are monitored by an external monitor or speaker, and an audio signal or the like input by a microphone or the like. Are mixed with the reproduced video signal and audio signal, and are sequentially input (FIG. 20B).

The system control circuit 34 controls the optical disk 12
The data transfer speed and the rotation speed of the optical disk 12 are set to twice those of the normal mode. In this state, the optical head 11 seeks to the reproduction start position of the program selected by the user (FIGS. 20 (C) and (D1)), and reproduction of the user data DU is started from this position. Further, the reproduced user data is stored in the memory 54, and the stored user data is output via the decoder 52 (FIG. 20).
(D2)). When a predetermined amount of user data is stored in the memory 54 in this state, the system control circuit 34 suspends the reproduction, and seeks the optical head 11 to the position at which the reproduction is started (FIG. 20 (D3)). Here, since the reproduced user data is processed by the external device and sequentially stored in the memory 54, the user data stored in the memory 54 is overwritten, for example, in a corresponding portion of the optical disc 12 (FIG. 20 ( D4)). As a result, when the recording-side user data amount or the reproducing-side user data amount stored in the memory 54 becomes equal to or less than a predetermined value, the user data is reproduced from the position where the reproduction was interrupted, and these controls are repeated.

Thus, the system control circuit 34 intermittently reproduces the user data DU from the optical disc 12,
The user data processed by the external device is intermittently re-recorded at the reproduction position of the user data DU. The system control circuit 34 also maintains the rotation speed of the optical disc 12 at the rotation speed of the recording side channel for the reproduction side channel in the post-recording mode, thereby reducing the frequency of switching the rotation speed of the optical disc 12 to reduce the access speed. To improve.

FIG. 22 is a schematic diagram showing a case where the user selects the pointer reproduction mode. In this case, the system control circuit 34 determines based on the file management data recorded in the lead-in area of the optical disc 12, and
Each program recorded on the optical disk 12 is sequentially searched and reproduced for a predetermined period. Therefore, the system control circuit 34
According to the file management data, the optical head 1
1 is sought to find the beginning (FIG. 22 (B)), and the reproduction of the optical disk 12 is started from the position where the beginning was found (FIG. 2).
2 (A1), (B)). Further, the reproduced user data is output via the memory 54 (FIG. 22C).

When a sufficient amount of user data is accumulated in the memory 54 after a predetermined time has elapsed, the system control circuit 34 seeks the optical head 11 to find the next program (FIG. 22 (A2)). Then, after waiting for the amount of user data in the memory 54 to be reduced to a predetermined value or less, the optical disc 12 is reproduced from the cue point (FIG. 22A
3)). The system control circuit 34 repeats these processes to sequentially locate and reproduce each program recorded on the optical disc 12.

FIG. 23 is a schematic diagram showing access to the optical disc 12 when recording and reproducing continuous data under the control of the system control circuit 34. The system control circuit 34 switches the target from the inner zone to the outer zone based on the address data ID detected by the address detection circuit 37, records successive data sequentially, and records the successive data. Reproduce.

At this time, when the system control circuit 34 controls the sled motor 36 to switch the access target from the inner zone to the outer zone Zm, the symbol G1
After starting access from the innermost groove as shown by, the entire operation is controlled so that the track by this groove is accessed to the outermost circumference of this zone Zm as shown by reference numeral G2. Subsequently, the system control circuit 34 instructs a track jump, as indicated by the symbol J, switches the access target to the track with the innermost land of the zone Zm, and switches from the track with the innermost land to the track (the symbol L1). ), The whole operation is controlled so that the track by this land is accessed to the outermost periphery of this zone Zm (reference numeral L2).

As a result, the system control circuit 34
When the optical disc 12 is driven by the LV, the user data DU is continuously recorded in a range where the rotation speed is maintained at a constant value. Record the DU. Thereby, in the optical disk device 10,
To the extent possible, the frequency of switching the rotation speed of the optical disk 12 is reduced, and the access speed is improved accordingly.

At this time, the system control circuit 34 first records the user data DU sequentially from the inner peripheral side to the outer peripheral side of the track by the groove in the range maintained at the constant rotational speed, and when this recording is completed, By sequentially recording user data on tracks by lands, the seek frequency of the optical head 11 is also reduced, thereby improving the access speed.

When the access to one zone is completed in this way, the system control circuit 34 switches the access target to the next outer zone, and the subsequent user data D from the track by the groove of this outer zone.
Start recording U. Thereby, the system control circuit 34
Controls the overall operation of each zone so that access is started from the track by the groove.

When an optical disk is accessed by an optical head having a high numerical aperture as in this embodiment, the recording and reproducing characteristics are degraded by dust and the like attached to the disk surface. According to the results of the experiment, as shown in FIG. 24, when the numerical aperture is 0.8, a burst error occurs even with small-diameter dust (due to dust of 100 [μm] or more). It was found that even if dust or the like adhered, the bit error rate was reduced. For this reason, in this embodiment, the optical disk 12 is stored and held in a cartridge.

FIG. 25 is an exploded perspective view showing a cartridge for storing the optical disk 12. As shown in FIG. In this embodiment, the optical disk 12 is stored in the cartridge 60 so as not to be easily taken out and held.
To load. FIG. 25 shows a state where the shutter is removed.

That is, the optical disk 12 has the sheet material 61
And 62 are arranged on both sides and housed in the upper case 63 and the lower case 64. Here, the sheet materials 61 and 62 are
The nonwoven fabric is formed by punching into a substantially disk shape, and this nonwoven fabric is formed of fibers having fine irregularities on the surface. Thereby, in the cartridge 60, the optical disk 12
Is rotated, dust on the surface of the optical disk 12 is removed from the sheet material 6.
1 and 62, and both sides of the optical disk 12 are cleaned by the sheet materials 61 and 62.

Further, the sheet members 61 and 62 are formed to have a diameter larger than that of the optical disk 12, and the periphery (indicated by hatching in the drawing) is adhered to the periphery of the optical disk 12 by an adhesive. Thereby, the sheet materials 61 and 6
Numeral 2 is formed in a bag shape for accommodating the optical disk 12 therein, and protects the optical disk 12 so that dust or the like entering the cartridge 60 does not easily adhere to the optical disk 12.

Further, the sheet members 61 and 62 are formed with notches near the center of rotation of the optical disk 12 and extending outward from the vicinity of the center of rotation, and the notches 61A and 62A near the center of rotation are used in the optical disk device 10. The optical disk 12 is formed so that it can be chucked, and the optical disk 12 can be accessed by notches 61B and 62B extending from the vicinity of the center of rotation.

Here, as shown in FIG. 26, the notches 61A and 62A near the center of rotation are formed to the minimum necessary size for chucking the optical disk 12. Notches 61B, 6 extending from near the center of rotation
2B is formed to the minimum necessary size for the optical head 11 to access. Specifically, in this embodiment,
When the optical disk device 10 accesses the optical disk 12 with a small working distance, even if the optical head 11 seeks, the first lens 17 of the optical head 11 can be used.
A is formed in a shape such that the component parts such as the modulation coil 18 do not come into contact with A.

As a result, the sheet members 61 and 62 cover the surface of the optical disk 12 except for the vicinity of the rotation center of the optical disk 12 and the range that impairs the incidence of the laser beam.
The optical disk 12 is not exposed as much as possible. When the information recording surface is formed only on one side of the optical disc 12, only one of the sheet materials 61 and 62 is formed with a notch near the center of rotation.

The upper case 63 and the lower case 64 are formed by injection-molding a resin. The upper case 63 and the lower case 64 correspond to the notches 61B and 62B of the sheet members 61 and 62, respectively. Openings 63A and 64A extending in the outer peripheral direction of the optical disk 12 are formed. Here, an opening is formed in the vicinity of the rotation center so as to chuck the optical disk 12 and in the outer peripheral direction of the optical disk 12 from the vicinity of the rotation center in order to dispose the optical head 11 close to the rotation center.

For this reason, the optical disc 12
In the outer circumferential direction, the opening is formed wider than the notches 62B, 62B of the sheet materials 61, 62. When the optical disc 12 has an information recording surface on only one side, an opening is formed only in the vicinity of the center of rotation in either the upper case 63 or the lower case 64.

Further, in the lower case 64, pressing members 65-1 and 65-2 are arranged near the opening 64A, on the side where the information recording surface of the optical disk 12 enters the opening 64A. The member 62 is pressed, and the sheet member 61 is pressed by the pressing member 65-2 to press the sheet members 61 and 62 against the optical disc 12. Here, the pressing members 65-1 and 65-2 are formed by bending a metal plate material into a spring shape. Thereby, the optical disk 12
Are designed to increase the cleaning effect of the sheet materials 61 and 62.

Further, as shown in FIG.
In the lower case 64, corners opposite to the openings 63A and 64A are assigned to the identification areas 63B and 64B of the optical disc 12, and the identification areas 63B and 64B have rectangular shapes according to the optical disc 12 held therein. A recess 66 is formed. Thereby, in the cartridge 60, the optical disk 1
The two types can be easily and reliably identified. When the optical disk 12 to be housed inside is a so-called double-sided disk having information recording surfaces on both sides, the upper case 63 and the lower case 64 are each provided with an identification area 63.
In the case where the optical disc 12 has an information recording surface on only one side while the optical discs B and 64B are formed, an identification area is formed only for one of the upper case 63 and the lower case 64.

Further, the upper case 63 and the lower case 64
Access restriction setting areas 63C and 64C are formed in the remaining corners, and a slide switch 67 is arranged in these setting areas 63C and 64C. Here, this slide switch 6
Reference numeral 7 is formed so as to slide as shown by the arrows to form through holes in the setting areas 63C and 64C and to close the through holes. Thus, in the cartridge 60, the slide switch 67 can be operated to set a write-protected state for each surface of the optical disk 12. When the optical disc 12 has an information recording surface on only one side, an access restriction setting area is formed only for one of the upper case 63 and the lower case 64.

The cartridge 60 is formed by arranging the shutter 68 with the optical disk 12 stored in the upper case 63 and the lower case 64 in this manner. Here, the shutter 68 is formed by bending a metal plate material,
Alternatively, it is formed by injection molding a resin, and is formed in a U-shaped cross section. The shutter 68 is arranged so as to close the openings 63A and 64A of the upper case 63 and the lower case 64, and slides by the loading mechanism of the optical disc device 10 to expose the openings 63A and 64A.

In correspondence with the shutter 68, the upper case 63 and the lower case 64 are provided with buffer members 63D and 64D so as to surround the openings 63A and 64A. Here, as shown in FIG. 28, the buffer members 63D and 64D are formed by punching a felt sheet material, for example, a felt sheet material into a shape surrounding the openings 63A and 64A.
These are attached to the upper case 63 and the lower case 64, respectively, and are arranged. Thus, when the openings 63A and 64A are closed by the shutter 68, the cartridge 60 is provided with cushioning members 63D and 64D so that dust and the like do not enter through the gap between the shutter 68 and the upper case 63 and the lower case 64. It is made to block.

Further, the upper case 63 and the lower case 64
As shown by arrows A and B (FIG. 27), openings 63A, 6
A movable restriction mechanism for restricting the slide of the shutter 68 is disposed at the corner on the 4A side. Here, the buttons 70A and 70B are arranged on both sides of the movable restriction mechanism so as not to protrude from the grooves formed on both sides of the cartridge 60. Further, the movable restricting mechanism includes a shutter 68 covering the openings 63A and 64A,
Buttons 71A and 71B are arranged on the side surface of the cartridge 60.

FIG. 29 is a plan view showing one of the movable restriction mechanisms indicated by reference numeral A in FIG. In this movement restriction mechanism, the button 70A is formed such that a part of the rotating member 72A protrudes from the side surface. Here, the rotating member 7
2A is formed by injection molding a resin,
It is rotatably held around a rotation shaft 73A arranged at the corner of the zero. Furthermore, the pivot member 72A is formed with a large shape on the base side of the button 70A so that only the button 70A protrudes from the window formed on the side surface of the cartridge 60.
Through A, it is connected to the first stopper 75A.

The first stopper 75A is formed by injection-molding an elastic resin, and is rotatably supported by a rotating shaft 76A. The first stopper 75A is formed so that two arms extend from the vicinity of the rotation shaft 76A, and one of the arms is connected to the upper case 63 or the lower case 6.
4 is hooked on the projection 77A formed on the
7A and the elastic force of the arm hooked on the projection 77A presses the entirety in the direction of turning to the button 70A side as shown by the arrow C. The first stopper 75A
The other arm is connected to the rotating member 72A via the connecting member 74A.
Is linked to As a result, the first stopper 75A
As shown by arrow D, the rotating member 72A is pressed so that the button 70A protrudes from the window of the cartridge 60. The rotating member 72A pushes the first side of the button 70A against the window of the cartridge 60 by pressing the button 70A. The rotation of the stopper 75A is limited.

Further, the first stopper 75A is configured such that one arm is bent substantially at a right angle from the connection portion of the connecting member 74A and extends substantially in parallel with the side surface. It bends to the shutter side.
The first stopper 75A regulates the movement of the second stopper 79A at the tip of the arm bent on the side surface on the shutter side.

That is, the second stopper 79A is
The same resin as the stopper 75A is formed by injection molding, and is rotatably supported on a predetermined rotating shaft 80A. Second
The stopper 79A is 2
One arm is formed to extend, and one of the arms is formed with a button 71A. Furthermore, the tip of the other arm of the second stopper 79A is hooked on the projection 81A.
Here, the protrusion 81A is formed on the back side of the arm of the first stopper 75A so as to protrude from the case 63 or 64. As a result, the second stopper 79A is
The whole is pressed by the elastic force of the arm hooked on 7A so as to rotate toward the button 71A as shown by the arrow E.

Further, the second stopper 79A is formed such that the tip of the arm on the button 71A side extends to the root of the shutter 68, and the tip of the arm engages with the projection of the shutter 68. Shutter 6
In the state of being engaged with the projection of No. 8, the first part
The stopper 75A is formed such that the tip of the arm of the stopper 75A abuts.

As a result, the movement of the second stopper 79A is regulated by the first stopper 75A so that the button 71A is displaced inside the cartridge 60 and the engagement with the shutter 68 is not released. .

Thus, in the cartridge 60, the one movement restricting mechanism prevents the opening from being exposed by sliding the shutter 68 due to a user's erroneous operation or the like, thereby effectively preventing the entry of dust and the like.

In this way, as shown in FIG. 30, in this movable restriction mechanism, a button 70A protruding from the side surface of the cartridge 60 is pressed by a predetermined pressing member 82A to thereby connect the connecting member as shown by an arrow F. 74
The first stopper 75A is rotated via A, and the tip of the arm of the first stopper 75A is further away from the back of the second stopper 79A, whereby the first stopper 75A is disposed on the second stopper 79A. The button 71A is held in a displaceable state.

Further, as shown in FIG. 31, by pressing the button 71A disposed on the second stopper 79A in this state, the shutter 68 and the second stopper 7
9A is disengaged, and then, as shown in FIG.
The shutter 68 is movable on the assumption that the movement is not restricted by the other movable restriction mechanism. Thereby, in the cartridge 60, the shutter 70 can be slid by sequentially pressing the buttons 70A and 71B in one of the movable restriction mechanisms, so that the opening is not exposed by a simple erroneous operation by the user. I have.

FIGS. 33 to 35 are plan views showing the other movable restriction mechanism. The other movable limiting mechanism is formed symmetrically with the one movable limiting mechanism described with reference to FIGS. 29 to 32, as shown by substituting the corresponding reference numerals. Thus, when a so-called double-sided disc is stored, the cartridge 60 is turned over and loaded into the optical disc apparatus 10 so that it can be easily loaded as in the case of a single-sided optical disc. However, a single-sided disk and a double-sided disk can be loaded by a common loading mechanism.

The other movable restricting mechanism operates in the same manner as the one movable restricting mechanism until the button 70B on the side is pressed to release the restriction on the rotation of the second stopper 79B. 35, the button 71B is pressed by the shutter 68 to slide the shutter 68, as shown in FIG.

As a result, in the cartridge 60, entry of dust and the like due to erroneous operation of the shutter 68 is effectively prevented by the triple safety mechanism.

FIG. 36 is a perspective view showing the relationship between the movement limiting mechanism and the loading mechanism of the optical disk device 10. In the optical disk device 10, a predetermined tray 85
The optical disk 12 is loaded by pulling the cartridge 60 into the disk. The tray 85 has protrusions 82A and 82B formed of pressing members disposed on the inner side surface.
When the cartridge 60 slides up to a predetermined position,
The projections 82A and 82B allow the buttons 70A and 70
Press B.

Further, in the optical disk device 10, two rollers 83 and 84 are arranged behind the tray 85. Here, the two rollers 83 and 84 are attached to the tip of an arm supported by a predetermined rotation shaft, and are urged toward the tray 85 as shown by an arrow G. When the cartridge 60 slides to a predetermined position, the two rollers 83 and 84 push the button 70.
With A and 70B pressed, the roller 83 contacts the button 71A and the end of the shutter 68, and the roller 84 contacts the button 71B and the shutter 68.

When the cartridge 60 further slides, one roller 83 presses the button 71A to slide the shutter 68, and the other roller 84 presses the button 71B and the shutter 68. The shutter 68 is slid to expose the opening as shown by the arrow H. In the optical disk device 10, when the shutter 68 is completely opened in this way, the optical head 11 approaches the optical disk 12 from below the cartridge 60 in the drawing, and thereafter processing such as focus search is performed.

On the other hand, when the cartridge 60 is ejected, in the optical disk device 10, during loading, the shutter 68 is pressed by the button 71B and the other roller 84 which is rotated by being pressed by the shutter 68. Return to the state. Roller 8
Even with only 3, the shutter 68 can be returned to the original state by a spring provided inside the cartridge.

When a single-sided disk is stored in the cartridge 60, the upper case 63 and the lower case 64 are so controlled as to restrict the shutter 68 from sliding in one direction.
Is formed, whereby erroneous mounting can be effectively avoided.

FIG. 37 shows the identification area 63B or 64B,
FIG. 3 is a schematic diagram illustrating a relationship with the optical disc device 10. In the optical disk device 10, a plurality of switches 87A to 87 arranged corresponding to the concave portions 66 of the identification area 64B.
D forms a disc discriminator 50.

That is, these switches 87A to 87D
Performs an on / off operation in accordance with the presence or absence of the concave portion 66 in the identification area 64B, and outputs a quaternary determination signal obtained by the on / off operation to the system control circuit 34.

[0211] The system control circuit 34
When 0 is inserted into the tray 85, a predetermined driving mechanism is driven to load the cartridge 60, and the type of the optical disk 12 stored in the cartridge 60 is determined based on the determination signal of the disk discriminator 50. I do. Further, the system control circuit 34 loads the corresponding reference laser light amount held in the memory 42 based on the determination result, and sets the driving conditions of the laser drive circuit 57 based on the reference laser light amount. Here, the memory 42 stores various optical discs 1 in addition to the frequency division ratio of the frequency divider 35B described above.
2 is maintained.

Thus, at the time of writing, the system control circuit 34 irradiates the optical disk 12 with the laser beam L at a reference light amount corresponding to the type of the optical disk 12, and obtains the final writing laser beam from the irradiation result of the laser beam L. The light amount is set, and when the optical disk 12 is a magneto-optical disk, the modulation coil driving circuit 56 is driven to apply a modulation magnetic field to the laser beam irradiation position.

FIG. 37 shows the identification area 63B or 64B,
FIG. 3 is a schematic diagram illustrating a relationship with the optical disc device 10. In the optical disk device 10, a plurality of switches 87A to 87 arranged corresponding to the concave portions 66 of the identification area 64B.
D forms a disc discriminator 50.

That is, these switches 87A to 87D
Performs an on / off operation in accordance with the presence or absence of the concave portion 66 in the identification area 64B, and outputs a quaternary determination signal obtained by the on / off operation to the system control circuit 34.

The system control circuit 34 controls the cartridge 6
When 0 is inserted into the tray 85, a predetermined driving mechanism is driven to load the cartridge 60. When the cartridge 60 is loaded, the type of the optical disk 12 stored in the cartridge 60 is determined based on the determination signal of the disk discriminator 50. I do. Further, the system control circuit 34 loads the corresponding reference laser light amount held in the memory 42 based on the determination result, and sets the driving conditions of the laser drive circuit 57 based on the reference laser light amount. Here the memory 42
Holds the reference laser light amount of various optical disks 12 in addition to the frequency division ratio of the frequency divider 35B described above.

At the time of writing, the system control circuit 34 irradiates the optical disk 12 with the laser beam L at a reference light amount corresponding to the type of the optical disk 12, and obtains a final writing laser beam from the irradiation result of the laser beam L. The light amount is set, and when the optical disk 12 is a magneto-optical disk, the modulation coil driving circuit 56 is driven to apply a modulation magnetic field to the laser beam irradiation position.

(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 so as to spiral from the inner circumference toward the outer circumference. By irradiating the laser beam L, 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, 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 with reference to the groove. At this time, the data is formed so that data of a capacity of 8 GB or more can be recorded by land / groove recording with a linear recording density of about 0.21 [μm / bit] based on the groove. As a result, the mastering apparatus 1 can record data having a capacity of 8 GB or more on the optical disc created from the master disc 2 by effectively utilizing the information recording surface.

At this time, in the mastering device 1, in the address signal generation circuit 6, the address data ID whose value sequentially changes in accordance with the rotation of the disk master 2 (FIG.
(A)) is formed, and synchronization data and the like are added to the address data ID to form data to be allocated to the address area AR2. Further, after the data is modulated, it is combined with the wobble signal WB in the combining circuit 8 and then 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.

As a result, in the optical disk formed by the master disk 2, a sector structure is formed.
Access can be made in units of each sector based on the address data, and the access speed is improved accordingly. At this time, even if 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.

When the sector structure is formed in this manner, in the mastering device 1, the disk master 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 used efficiently by accessing the optical disk by applying the LV method, and the access speed can be improved.

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 data is recorded at a high density by land / groove recording. Even in this case, the address data can be reliably reproduced by effectively avoiding crosstalk from the adjacent track.

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

In this optical disk (FIG. 5), 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. Accordingly, even when a laser beam is irradiated from an optical system having a high numerical aperture through a light transmitting layer, the relationship is set so as to satisfy the relational expressions of the expressions (2) and (3), and the influence of the skew is made effective. The information is formed so that desired data can be reliably recorded and reproduced on this information recording surface.

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

That is, the optical disk 12 is irradiated with a laser beam from the optical head 11 in the optical disk device 10 (FIGS. 7 and 8), the return light is received by the optical head 11, and a signal is output according to the amount of the return light. The reproduction signal RF whose level changes, the reproduction signal MO whose signal level changes according to the polarization plane of the return light, the push-pull signal PP whose signal level changes according to the displacement of the laser beam irradiation position with respect to the groove or pit row, A focus error signal FE whose signal level changes according to the focus amount is detected.

At this time, the working distance WD is 5
By irradiating a laser beam having a wavelength of 650 [nm] through an objective lens 17 having a numerical aperture of 0.78 set to 60 [μm], the spot size is reduced to about 比較 as compared with that of a DVD. Density can be recorded. This allows efficient PRM in channel coding
By applying L, and by adopting an efficient premastered address and reducing the redundancy, the recording capacity can be set to about 8 [GB].

At this time, the working distance is 5
By setting it to 60 [μm], the curvature of the lens, the eccentricity tolerance between the lens surfaces, and the surface angle tolerance can be set to practically sufficient ranges, and the optical system can be formed by a small-diameter lens. 4.5 which is close to DVD which is considered to be a practical limit
A laser beam can be incident on the objective lens with a beam diameter of [mm] or less. This makes it possible to produce the optical head 11 with sufficient accuracy, and also prevents collision of the objective lens 17 with the optical head.

The wobble signal WB is extracted in the wobble signal detection circuit 39 from the push-pull signal PP thus detected, and the wobble signal WB is extracted.
Is binarized to extract edge information. Further P
In the LL circuit 35, 2 having the edge information
The value signal S1 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 the 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, write / read clock R / W
The CK is counted by the cluster counter 38 based on the frame synchronization timing detected from the address area AR2 by the address detection circuit 37, and the write / read timing in the recording / reproduction circuit 53 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 manner, the PLL circuit 35 switches the frequency division ratio of the frequency divider 35B according to the laser beam irradiation position.
Thus, the optical disc 12 is driven to rotate by the ZCLV.

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. 6), by controlling the recording / 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.

When the optical disk 12 is a magneto-optical disk, the write / read clock R /
In a state where the light amount of the laser beam is intermittently raised at the timing synchronized with WCK, the modulation coil driving circuit 56 applies a modulation magnetic field to the laser beam irradiation position in accordance with the data of the ECC block that has been subjected to the modulation processing. By applying the method of thermomagnetic recording, the maximum run length 8T and the minimum run length 2T marks are sequentially formed by the shortest recording mark 4/3 bits, and the user data DU is recorded by the linear recording density 0.21 [μm / bit]. Then, a video signal and an audio signal for 3 hours are continuously recorded.

As a result, when the redundancy is 23% or less,
Video and audio signals are recorded efficiently.

Also, by recording video and audio signals sequentially on the optical disk in units of 32 [KB] ECC data blocks, a sufficient inter-code interval in error correction processing is ensured, and the bit error rate is improved. You. Further, by performing recording / reproduction in units of ECC data blocks, a special reproduction mode in which recording / reproduction processing is alternately switched, and data processing in the case of discretely recording data with a seek interposed therebetween are simplified. You.

In these cases, when the optical disk 12 is a phase change type or a write-once type, the (1, 7) R is synchronized with the write / read clock R / WCK.
In accordance with the LL-modulated ECC block data, the laser drive circuit 57 intermittently switches the light amount of the laser beam, thereby forming a similar pit row and a linear recording density of 0.21 [μm / bit]. User data DU is recorded with a minimum mark length or a minimum pit length of 0.3 [μm] or less, and a video signal and an audio signal for 3 hours are continuously recorded.

As a result, in the optical disk device 10, the same usability as that of the video tape recorder is ensured for the recording time.

Further, the information is recorded on the optical disk by land-groove recording, whereby the video signal and the audio signal are recorded efficiently by effectively utilizing the information recording surface.
Also, recorded with a track pitch of 0.5 [μm],
Video signals and audio signals for three hours are recorded on one 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.

When accessing the optical disk 12 in this way, the optical disk device 10 uses the large-capacity memory 5
4, user data is input and output between the encoder 51 and the decoder 52, and the optical disk 12
User data is intermittently recorded at a data transfer rate of 11.08 [Mbps], which is higher than the data transfer rate between the encoder 51 and the decoder 52.
It will be played again. This allows user data to be recorded discretely in units of clusters, ensuring a sufficient seek time.
Continuous video and audio signals can be recorded and reproduced without interruption. In addition, each program recorded on the optical disk 12 can be searched for and reproduced by pointer reproduction.

When the user selects the chase reproduction, multi-channel mode, or post-recording mode for simultaneously processing two-channel video and audio signals, the rotation speed of the optical disk 12 is switched to twice the normal rotation speed. Can be Thus, the optical disk device 1
In the case of 0, a sufficient vacant time is secured between accesses to the optical disk 12 for intermittently recording and reproducing the continuous video signal and audio signal on the optical disk 12 via the memory 54. In the optical disk device 10, the idle time is allocated to recording and reproduction of another channel and to the seek of the optical head 11, whereby video signals and audio signals of two channels are simultaneously processed.

In accessing the optical disk 12 in this manner, in the optical disk device 10, an optical disk having a light transmitting layer thickness of 0.1 [mm] is accessed by an optical system having a high numerical aperture. As a result, the signal levels of the reproduction signals RF and MO also change due to small dust or the like deposited on the surface of the optical disk 12, and the error rate may be degraded as compared with the related art.

For this reason, the optical disk 12 (FIG. 25) is stored in the cartridge 60 so as not to be easily taken out, and is loaded into the optical disk device 10 by the cartridge 60, thereby preventing dust and the like from adhering.

At this time, the optical disk 12 is housed in the bag-shaped sheet materials 61 and 62 and housed in the cartridge 60, and the pressing members 65 press the sheet materials 61 and 62. The gaps between the shutter 68 and the upper case 63 and the lower case 64 are closed by the buffer members 63D and 64D, thereby effectively preventing dust and the like from adhering.

The cartridge 60 (see FIGS. 29 to 3)
3) After pressing the buttons 70A and 70B arranged on the side surface to release the regulation of the movement of the second stoppers 79A and 79B by the first stoppers 75A and 75B, the button 71A or 71B is pressed to 2 stoppers 79A
Or, it is formed so as not to slide unless the engagement between the shutter 79B and the shutter 68 is released, so that the openings 63A and 64A are not exposed by the user's erroneous operation, and the intrusion of dust and the like due to such erroneous operation is effectively avoided. Is done.

Thus, the cartridge 60
When the optical disk 12 is placed on the tray 85 (FIG. 36), the drive mechanism is driven by the system control circuit 34 to slide on the tray 85, and the projections 82A, 82B formed on the tray 85 are moved. Presses the buttons 70A and 70B of the cartridge 60. Thereafter, the cartridge 60 is pressed by the roller 83 with the button 71A.
Is pressed, and the shutter 68 is pressed, whereby the shutter 68 slides to open the openings 63A and 64A.
A is exposed, and the optical head 11 enters the openings 63A and 64A to complete the loading of the optical disk 12.

In this state, the optical disk device 10 (FIG.
7) Optical disk 12 accessed by optical head 11
The disc discriminator 50 detects the presence or absence of the concave portion 66 in the identification area 63B or 64B formed in the cartridge 60 corresponding to the information recording surface, and thereby determines the type of the information recording surface. The cartridge 60
By setting the switch 67, it is detected whether or not this information recording surface is set to be write-protected.

Thus, in the optical disk device 10, when the optical disk 12 is a magneto-optical disk, the operations of the modulation coil drive circuit 56 and the laser drive circuit 57 are started, and the user data DU is thermomagnetically recorded on the optical disk 12. The optical disk 12 is a phase change optical disk,
In the case of a write-once optical disc, the operation of the laser drive circuit 57 is started, and the user data DU is recorded by a mark row or a pit row.

At this time, in the optical disk device 10, the optical disk 12 is irradiated with the laser beam L by the reference laser light amount corresponding to the type of each optical disk held in the memory 42, and based on the irradiation result of the laser beam L,
The optimal light quantity is set. Thus, the optical disk device 10 can record desired data on various optical disks 12.

At this time, in the optical head 11 (FIG. 8), the modulation coil 18 disposed on the objective lens 17 side applies a modulation magnetic field to the optical disk in which the thickness of the light transmission layer is set to 0.1 [mm]. When the optical disk 12 is accessed by an optical system having a high numerical aperture,
Various data can be recorded not only for the phase-change optical disk and the write-once optical disk, but also for the magneto-optical disk, so that the application range of the optical disk device 10 is greatly expanded.

(1-3) Effects of the First Embodiment According to the above configuration, the working distance 560
Objective lens 17 with a numerical aperture of 0.78 set to [μm]
By irradiating a laser beam having a wavelength of 650 [nm] through the interface and recording user data based on a video signal and an audio signal, data processing conditions are selected.
[GB] data can be recorded, so that the function unique to the optical disk device can be effectively used.
In addition, the same usability as a video tape recorder can be obtained. Further, an accident such as collision with an optical disk can be effectively avoided, and the optical head 11 can be manufactured with sufficient accuracy.

The linear recording density is 0.21 [μm / bit].
The shortest recording mark length and the shortest pit length 0.3
[Μm] By recording user data below, and by recording user data by land / groove recording with a track pitch of 0.5 [μm], 8 [GB] data can be recorded. Accordingly, the function unique to the optical disk device can be effectively used, and the same usability as a video tape recorder can be obtained.

Further, by setting the user data transfer speed between the optical disk and the buffer memory to 11.08 [Mbps] and increasing the speed compared with the user data transfer speed between the decoder, encoder and the buffer memory, it is possible to seek data. In this case, a continuous video signal can be recorded and reproduced with a sufficient time.

Furthermore, by recording user data with a redundancy lower than the DVD redundancy of 23%, user data can be efficiently recorded.

The variation in the thickness of the light transmitting layer is Δt, the numerical aperture NA and the wavelength λ are Δt ≦ ± 5.26 × (λ / NA
⁴ ) By satisfying the relationship of [μm],
Video signals and audio signals can be recorded at high density and reliably recorded and reproduced.

Further, by accessing the optical disk 12 stored in the cartridge 60, it is possible to reduce the influence of dust, thereby effectively preventing deterioration of the recording / reproducing characteristics due to dust and the like.

Further, by changing the rotation speed of the optical disk in a stepwise manner and accessing the optical disk by the ZCLV, by arranging a plurality of sectors in one round of the track and recording the address at the head of each sector, A video signal can be recorded by efficiently using the information recording surface of the optical disk, and a reduction in access speed can be effectively avoided.

Furthermore, the recording density can be improved by efficiently using the information recording surface of the optical disk by land-groove recording.

Furthermore, the user data transfer speed between the optical disk and the buffer memory is twice as high as the user data transfer speed between the decoder, the encoder and the buffer memory, so that the optical disk can be accessed intermittently. By effectively utilizing the remaining free time, it is possible to execute simultaneous parallel processing of a plurality of channels and the like, thereby improving the usability of the optical disc apparatus.

Further, user data is recorded / reproduced in ECC data block units, and ECC data blocks are
By setting B or more, a sufficient inter-code interval in the error correction processing can be ensured, and a sufficient error correction capability can be ensured. Further, by recording and reproducing the data on the optical disk in units of the ECC data block, it is possible to execute the simultaneous parallel processing of two channels or the like by the simple processing as a whole.

(2) Second Embodiment FIG. 38 is a block diagram showing a mastering device according to a second embodiment of the present invention. In the manufacturing process of the optical disc according to this embodiment, the mastering device 10
Exposure of the master disc 2 by 1
More optical disks are manufactured. In this embodiment, the same components as those in the first embodiment are denoted by the corresponding reference numerals, and the duplicate description will be omitted.

In this embodiment, the mastering device 101 forms tracks by grooves at a track pitch of 1.0 [μm] in a helical manner. Also, when an optical disk was created from this master disk 2,
The laser beam L is applied so that the widths of the groove and the land become substantially equal. Further, the groove is meandered by the wobble data ADIP generated by the wobble data generation circuit 106.

Thus, in this embodiment, addresses are pre-formatted by meandering grooves instead of pit strings. Further, even if the address is preformatted by the meandering of the groove, highly accurate position information can be obtained, and the same recording capacity as in the first embodiment is secured from these facts.

That is, the wobble data generation circuit 106
Receives a timing signal (comprising an FG signal or the like) synchronized with the rotation of the disk master 2 from the spindle motor 3 or the like, and counts this timing signal by a predetermined counter, whereby the disk master 2 rotates, for example, 1/16. Frame number sy whose value changes cyclically in a cycle
A track number track no whose value changes each time the irradiation position of the laser beam L is displaced by one track corresponding to the change of ncno and frame number sync no.

Thus, the wobble data generation circuit 10
6 is frame number sync no and track number track no
To generate address data. Here, the wobble data generation circuit 106 generates the frame number sync no and the track number track no using 4 bits and 20 bits, respectively.

Further, wobble data generation circuit 106
Calculates a predetermined operation by adding an 8-bit reserve bit rev to the frame number sync no and the track number track no, and using an information word M (x) based on the frame number sync no, the track number track no and the reserve bit rev. Executes the processing and sets the error detection code CRCC (Cyclic Redundancy C
heck Code). As a result, the wobble data generation circuit 106 sequentially generates address data blocks in the format shown in FIG. The wobble data generation circuit 106 stores each address data block in 48
Create with bits.

At this time, the wobble data generation circuit 106
Is set by inverting the logic level of the error detection code CRCC and by operating the reserve bit rev.
The wobble data ADIP is generated so that bit inversion always occurs once in one address data block.
If necessary, 4 bits are allocated to the data layer of the recording layer. Here, the optical disk created by the master disk 2 has a plurality of information recording layers, and the data of the recording layers
The information recording layer is specified by the layer. When setting the data layer of the recording layer, the data layer of the recording layer is also used as the information word M (x) as the error detection code CRCC.
Used to calculate

The wobble data generating circuit 106 sequentially generates address data frames in synchronization with the rotation of the disk master 2 and converts the generated address data frames into serial data synchronized with the rotation of the disk master 2. The serial data is sequentially output to the wobble signal generation circuit 107 as wobble data ADIP.

The wobble signal generation circuit 107 generates a wobble signal WB from the wobble data ADIP and the like. In the wobble signal generation circuit 107, the generation circuit 107A generates a reference signal having a frequency of 115.2 [kHz]. In this mastering device 101,
The spindle motor 3 is spindle-controlled using this reference signal, thereby generating a wobble signal WB synchronized with the rotation of the master disc 2. The frequency dividing circuit 107B divides the frequency of the reference signal having a frequency of 115.2 [kHz] by １ ／ to generate a reference clock having a frequency of 14.4 [kHz].

As shown in FIG. 40, the bi-phase mark modulation circuit 107C outputs a first reference clock synchronized with the phase of the reference clock having a frequency of 14.4 [kHz] according to the logic level of the wobble data ADIP. And a second reference clock whose frequency is set to に 対 し て with respect to the first reference clock, thereby bi-phase mark modulating the wobble data ADIP to generate a channel signal ch. .

At this time, the biphase mark modulation circuit 10
7C assigns a predetermined synchronization pattern to the head of each address data frame and generates a channel signal ch. (FIGS. 40 (A) to (E)). This synchronization pattern is a unique pattern that is not generated by bi-phase mark modulation, is assigned a pattern with DSV of 0, and has a polarity such that the signal level of the channel signal ch switches at the boundary with the address data frame. Is set. In this embodiment, while the channel run length of the channel signal ch is 1 or 2,
The synchronization pattern is 3T, 1 using a maximum run length of 3,
T, 1T, and 3T patterns are assigned.

The signal level of channel signal ch is inverted at a timing corresponding to the bit boundary of wobble data ADIP. When the logic level of wobble data ADIP is 0, a second reference clock is allocated and a constant Held at the logic level. Wobble data A
When the logical level of the DIP is 1, the first reference clock is assigned and the signal level is inverted at the timing corresponding to the center of the bit.

The frequency dividing circuit 107D has a frequency of 115.2.
[KHz] reference signal is frequency-divided by 、, and the frequency is set to 4 times the frequency of the phase modulation clock.
A phase modulation reference clock of 7.6 [kHz] is generated.

The phase modulation circuit 107E operates at the frequency 5
From a 7.6 [kHz] reference clock, a first carrier signal whose phase is synchronized with the reference clock and a second carrier signal whose phase is shifted by 180 degrees with respect to the reference clock are generated. The first and second carrier signals are selectively output according to the signal level of the channel signal ch (FIG. 40 (F)). Thereby, the phase modulation circuit 10
7E phase-modulates the channel signal ch and outputs the modulated signal as a wobble signal WB.

As a result, as shown in FIG. 41, the wobble signal generation circuit 107 modulates the wobble data ADIP by biphase mark modulation (FIGS. 41A and 41B), and then interpolates a single synchronization pattern. A phase modulation signal with one carrier frequency is generated, and this phase modulation signal is output as a wobble signal WB (FIG. 41 (C)).

In this embodiment, the laser beam irradiation position is meandered according to the wobble signal WB, and an optical disk similar to that of the first embodiment is produced from the disk master 2.

FIG. 42, which is shown in comparison with FIG. 6, 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 110, the wobble data ADIP is detected from the push-pull signal PP obtained from the optical head 11 to detect the laser beam irradiation position.

That is, the frame address detection circuit 137
Is a push-pull signal PP output from the optical head 11
Then, a wobble signal is extracted by a built-in band pass filter. Further, the frame address detection circuit 137
Detects the phase change of the wobble signal and executes predetermined signal processing to obtain wobble data ADIP.
, And outputs the demodulated wobble data ADIP to the system control circuit 34 and the cluster counter 38. As a result, the optical disk device 110 can roughly specify the laser beam irradiation position based on the wobble data ADIP in the system control circuit 34, and can confirm the frame synchronization timing in the cluster counter 38. ing.

Further, frame address detecting circuit 137
When outputting the wobble data ADIP, the wobble data ADIP is subjected to error detection processing using the error detection code CRCC assigned to each address data frame, and an error detection code and a reserved bit are determined for the wobble data ADIP determined to be correct. Remove and output.

The PLL circuit 135 supplies the binary signal output from the wobbling cycle detection circuit 40 to the phase comparison circuit (PC) 135A, where it compares the phase with the clock CK output from the frequency division circuit 135B. Here, FIG.
As shown in FIG. 43, in the frequency dividing circuit 135B, the binary signal S1 (FIG.
(A)), the clock CK whose frequency is doubled (FIG.
3 (B)). On the other hand, in the wobble signal WB, the mastering device 1
Since the data is generated by performing phase modulation in 01, each edge holds correct phase information.

As a result, in the PLL circuit 135, the phase of the binary signal S1 is compared with that of the clock CK at a frequency twice as high as that of the binary signal S1, and a low-pass filter (LP
F) The low frequency component of the phase comparison result is extracted by 135C, and the voltage controlled oscillator (VC
O) Control the oscillation frequency of 136D. Further, the oscillation output of the voltage control type oscillation circuit 136D is divided by a frequency dividing circuit 135B.
, So that a highly accurate clock CK can be generated.

In PLL circuit 135, frequency dividing circuit 13
5B is set by the setting of the system control circuit 134 so that the frequency division ratio sequentially increases as the laser beam irradiation position is displaced toward the outer peripheral side of the optical disk 12. Accordingly, the PLL circuit 135 sequentially increases the frequency of the oscillation output of the voltage control type oscillation circuit 136D with respect to the frequency of the wobble signal WB as the laser beam irradiation position is displaced to the outer peripheral side of the optical disc 12. The oscillation output is written to a write / read clock R
Output as / WCK.

This write / read clock R / W C
By rotating the optical disk 12 so that K has a constant frequency, the write / read clock R /
By recording desired data on the basis of WCK, in the optical disk device 110, the optical disk 112 is driven to rotate by ZCLV as in the first embodiment.

Further, the cluster counter outputs a cluster start pulse to the system control circuit based on the count result of the write / read clock R / WCK. Here, the cluster start pulse is a pulse that indicates the start timing of this cluster.

Thus, as shown in FIG. 44, in this embodiment, the information recording surface of the optical disk 12 is concentrically divided into a plurality of zones Z0, Z1,..., Zn-1, and Zn. The rotation speed of the optical disk is gradually reduced from the zone No. to the zone on the outer circumference side so as to set the same recording density in the zone on the inner circumference side and the zone on the outer circumference side.

At this time, by executing write / read control in accordance with the cluster start pulse output from the cluster counter 38, each zone is radially divided, and one cluster of data is allocated to each divided area. As a result, the system control circuit 134 sequentially increases the number of clusters in each zone from the inner zone to the outer zone.

In the optical disk device 110, the radius 24
The area of [mm] to 58 [mm] is divided into 81 zones of 840 tracks each. In the innermost zone, 1
The tracks are radially split to form 964 frames. Further, in the outer zone, each track is divided so that the number of frames is sequentially increased by 16 frames. The optical disk device 110 allocates and records one cluster of data to the continuous 420 frames thus formed.

Thus, in this embodiment, the optical disk device 110 accesses the optical disk 112 by land-groove recording and ZCLV, and records video signals and audio signals in various operation modes, as in the first embodiment. It has been made reproducible.

At this time, in this embodiment, the same ECC data block (FIG. 13) as in the first embodiment is formed, and a frame structure shown in FIG. 45 is formed for this ECC data block. That is, the optical disk device 110
Assigns a 2-byte frame synchronization signal (FS) to each 91 bytes of an ECC data block of 182 bytes × 208 bytes, thereby forming 416 frames with one ECC data block. Furthermore, this 41
A link frame of 2 × 2 frames is allocated to six frames. Thus, the recording / reproducing circuit 53 forms one cluster of data by the frame structure shown in FIG. The frame shown in FIG. 45 corresponds to the frame described above with reference to FIG.

[0294] Of these frames, the link frame is used as a buffer between adjacent clusters when data is recorded on the optical disk 112 in cluster units. That is, as shown in FIG.
In the case of 0, after 56 bytes of data and three link frames are sequentially recorded on the optical disk 112, subsequently, frames of ECC blocks are sequentially recorded. Top 5 of these
The 6 bytes and the 91 bytes following the frame synchronization signal are interposed, and the flow of the recording material due to overwriting is suppressed by using the phase change medium as the recording medium to improve the overwriting cycle of the recording area. To adjust the light intensity of the laser beam (pre guard /
APC) (APC: Automatic Power Control). Then, with the frame synchronization signal (FS) in between,
An area (Slice / PLL) for slice level adjustment and PLL synchronization during reproduction is allocated. Note that the laser beam light amount adjustment is also used for slice level adjustment during reproduction and for PLL synchronization. A 4-byte synchronization pattern (Sync) and a reserved area (Resarved) are set at the head and tail.

[0295] On the other hand, at the end of the frame by the ECC block, following the frame synchronization signal (FS), 1
A postamble of 90 bytes, a post guard and buffer of 90 bytes (Post guard / buffer), a post guard and buffer of 91 bytes with a frame synchronization signal interposed therebetween are allocated,
Between these, clusters to be recorded subsequently overlap each other. The postamble adjusts the mark length of the data and sets the signal polarity to a predetermined value.The postguard uses the phase change medium as the recording medium, and the fluidity of the recording material due to overwriting. This is an area for suppressing the write cycle and improving the overwrite cycle of the recording area. The buffer is an area for absorbing recording jitter due to eccentricity of the disk, recording sensitivity, and the like.

According to the above configuration, the same effect as in the first embodiment can be obtained even if wobble data composed of address data is recorded by meandering grooves instead of pit strings.

Since the pit row is omitted, the video signal and the audio signal can be recorded more efficiently and more efficiently by using the information recording surface of the optical disc than in the first embodiment.

(3) Third Embodiment FIG. 47 is a block diagram showing a mastering device according to a third 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 this mastering device, the same components as those of the mastering device described above with reference to FIGS. 1 and 38 are denoted by the corresponding reference numerals, and redundant description will be omitted.

In mastering device 161, wobble signal generation circuit 167 generates wobble data AD.
A wobble signal WB is generated from IP. In the wobble signal generation circuit 167, the generation circuit 167A
A predetermined reference signal is generated and output. The mastering device 161 controls the spindle motor 3 by using one of the reference signals generated by the generation circuit 167A, thereby generating a wobble signal WB synchronized with the rotation of the master disk 2.

The phase modulation circuit 167B wobbles the first reference clock φ1 synchronized with the phase of the reference signal and the second reference clock φ2 which is 180 ° out of phase with the first reference clock φ1. By allocating according to the logical level of the data ADIP, the wobble data ADIP is phase-modulated to generate a channel signal ch.

At this time, as shown in FIG. 48, the phase modulation circuit 167B forms an even-numbered channel in the first half and the second half of each bit at the timing tc corresponding to the center of each bit of the wobble data ADIP. (In this case, each has two channels), and the first and second reference clocks φ1 and φ2 are allocated so that the period of logic 1 and the period of logic 0 are equal in the first half and the second half, respectively.

That is, when the wobble data ADIP is logic 1, the phase modulation circuit 167B allocates the first reference clock for one cycle, and then allocates the second reference clock for one cycle. A channel signal ch is generated as shown in FIG.
(A) to (D)).

On the contrary, the wobble data AD
When IP is logic 0, the second reference clock is assigned for one cycle, and then the first reference clock is assigned for one cycle, thereby generating a channel signal ch so that 1001 channels are consecutively arranged.

The frequency modulation circuit 167C frequency-modulates the channel signal ch and outputs the modulated signal as a wobble signal WB. At this time, the frequency modulation circuit 167
C generates a wobble signal WB by frequency-modulating the channel signal ch without interposing a synchronization pattern,
The redundancy is reduced accordingly. Further, the frequency modulation circuit 167
C is the frequency n- for the logic 1 and 0 of the channel signal ch, where n is the center frequency of the frequency modulation.
The wobble signal WB is generated by assigning d and n + d sine wave signals. Further, at this time, sine wave signals of frequencies n−d and n + d are respectively assigned to the channel signals ch in units of 0.5 waves, whereby timings ts and tc corresponding to the bit center and the bit boundary of the wobble data ADIP are obtained. To generate a wobble signal WB so as to cross 0.

That is, an even-numbered channel is formed in the first half and the second half of each bit at the timing tc corresponding to the center of each bit of the wobble data ADIP. If the first and second reference clocks φ1 and φ2 are assigned so that the period of logic 0 is equal, the number of channels of logic 1 and the logic 0 in the first half and second half of the channel signal ch are respectively determined. The number of channels is kept the same.

If a sine wave signal of frequencies n−d and n + d is assigned to the channel signal ch in units of 0.5 wave, the sine wave signal within the period corresponding to the first half and the second half of each bit of the wobble data ADIP can be obtained. In the above, the wobble signal WB can be generated by canceling the phase shift with respect to the carrier signal of the frequency n. Therefore, the wobble signal WB can be generated such that zero crossing occurs at timings ts and tc corresponding to the bit center and the bit boundary of the wobble data ADIP.

Further, at this time, sine wave signals of frequencies n−d and n + d are assigned in 0.5 wave units, so that the timing at which the signal level of the wobble signal WB rises from 0 level or the signal level of the wobble signal WB becomes 0 level All of the falling timings are held at the timings ts and tc corresponding to the bit center and the bit boundary of the wobble data ADIP, and hold the correct phase information of the carrier signal.

Therefore, as shown in FIG. 49, if the wobble signal WB is binarized based on the 0 level, the rising edge or the falling edge coincides with the edge timing of the channel signal ch. The binarized signal S1 can be generated (FIG. 49A)
(D)). Therefore, it is possible to generate the clock CK and the wobble clock WCK with reference to the timing of the edge having the correct phase information, and to generate a highly accurate clock without frequency and phase fluctuations (FIG. 49).
(E) and (F)). As shown by the arrows, at the remaining edges, the phase differences + φ and −φ with respect to the clock CK generated in this way are the channel signals ch.
, The wobble data ADIP can be decoded on the basis of the phase differences + φ and −φ.

Thus, the wobble signal generation circuit 167
In, the groove is meandered by the wobble signal WB so that a highly accurate clock can be generated.

In this embodiment, various optical disks are manufactured from the disk master 2 in the same manner as in the first embodiment. Thus, in this optical disc, the timing at which the signal level of the wobble signal WB rises from the 0 level or the timing at which the signal level of the wobble signal WB falls from the 0 level all hold the correct phase information of the carrier signal. From that
The cycle in which the groove crosses the track center from the inner circumference to the outer circumference or the cycle in which the groove crosses the track center from the outer circumference to the inner circumference is formed to be constant, and the crossing timing coincides with the zero cross timing of the carrier signal. Will do.

FIG. 50 is a block diagram showing an optical disk device according to the third embodiment. In the optical disk device 170, the same components as those of the optical disk devices 10 and 110 described above with reference to FIGS. 6 and 42 are denoted by the same reference numerals, or the description thereof will be omitted, and the redundant description will be omitted.

In the optical disk device 170, the wobble signal processing circuit 173 extracts the wobble signal WB from the push-pull signal PP, and
B to process wobble clock WCK and clock C
K, a write / read clock R / W CK is generated. Further, the wobble signal processing circuit 173 detects the wobble data ADIP from the wobble signal WB and notifies the system control circuit 134 of the detected wobble data ADIP.

FIG. 51 shows the wobble signal processing circuit 1
It is a block diagram which shows 73. The wobble signal processing circuit 173 amplifies the push-pull signal PP by the amplification circuit 182 having a predetermined gain, and then extracts the wobble signal WB via a band-pass filter (not shown). As shown in FIG. 52, the comparison circuit (COM) 183 binarizes the wobble signal WB based on the 0 level to generate a binarized signal S2, thereby detecting edge information from the wobble signal WB (FIG. 52). (A) to (D)). Thus, in the binary signal S2, either the rising edge or the falling edge has the correct phase information, and the phase information of the remaining edge has the information of the wobble data ADIP. Will be.

A phase comparison circuit (PC) 184 is constituted by an exclusive OR circuit, compares the phase of the wobble clock WCK output from the frequency divider 185 with the phase of the wobble signal WB, and outputs a phase comparison result SCOM. (FIG. 52 (D)-(G)). Low-pass filter (LP
F) 186 limits the band of the phase comparison result and outputs the low frequency component to a voltage controlled oscillator (VCO) 187. The voltage controlled oscillation circuit 187 outputs a write / read clock R / W CK based on the output signal of the low-pass filter 186. At this time, the voltage-controlled oscillation circuit 187 generates the write / read clock R / WCK at a frequency four times the frequency of the wobble signal WB. The frequency divider 185 sequentially divides the frequency of the write / read clock R / W CK to generate a clock CK and a wobble clock WCK.

Thus, the phase comparator 184, the frequency divider 185, the low-pass filter 186, and the voltage-controlled oscillator 187 constitute a PLL circuit, and the timing at which the wobble signal WB rises at zero crossing (has correct phase information). Clock R synchronized in phase with
/ W CK, CK, and WCK are generated. In this case, the wobble clock WCK is generated by shifting the phase of the correct edge of the binary signal S2 by π / 2.

That is, in this embodiment, in this optical disk, the timing at which the signal level of the wobble signal WB rises from the 0 level or the timing at which the signal level of the wobble signal WB falls from the 0 level are all correct for the carrier signal. Since the phase information is held, when the wobble clock WCK is thus phase-synchronized with the binary signal S2, the phase comparison result SC obtained through the low-pass filter 186 is obtained.
The oscillation frequency is controlled so that the average value of OM becomes a constant value.

In this case, for example, the wobble clock WCK
(H) of FIG. 52, the average value of the phase comparison result SCOM decreases accordingly (FIG. 52 (H)).
(I)), the oscillation frequency is controlled so as to decrease. As a result, the PLL circuit generates various clocks based on the rise of the wobble signal WB having correct phase information.

By the way, in the binary signal S2 generated in this manner, the period during which the logic level rises, the period in which the logic level rises, and the period in which the logic level falls after the rise of the logic level until the rise again. The difference from the current period changes at the timing of the falling edge during this period T. That is, this difference
This means that the wobble signal WB has the phase information of the timing at which it crosses and falls.

The wobble signal processing circuit 73 reproduces the wobble data ADIP by effectively utilizing this relationship. That is, as shown in FIG. 53, the counter (CNT)
189, the count value is cleared on the basis of the rising edge of the binarized signal S2, and the write / read clock R / W CK is up-counted during the period when the logical level of the binarized signal S2 is rising. Conversely 2
During the period in which the logic level of the digitized signal S2 falls, the write / read clock R / WCK is down-counted (FIGS. 53A to 53F). Accordingly, the counter 189 determines the leading phase and the lagging phase of the wobble signal WB with respect to the wobble clock WCK in units of a half cycle of the wobble data ADIP as the count value CNT.
Is detected by

Flip-flop (FF) 190 counts this count value C for half a cycle of wobble data ADIP.
Delay NT. The subtraction circuit 191 subtracts the output data of the counter 189 from the output data of the flip-flop 190. As a result, the subtraction circuit 91 detects a change in the timing at which the wobble signal WB crosses zero before and after the bit boundary and the bit center of the wobble data ADIP, and this timing advances with respect to the wobble clock WCK. In this case, the subtraction result of the negative value L2 is output at twice the count value CNT. Conversely, when the timing changes so as to be delayed with respect to the wobble clock WCK, the count value CNT is doubled and a subtraction result of the positive value H2 is output, and the phase does not change. Outputs the result of subtraction of the value 0 (FIG. 53 (G)).

Thus, the bit boundary,
If the timing at which the wobble signal WB crosses 0 does not change before and after the bit center as a reference, it is possible to determine a bit boundary between the two before and after according to the modulation rule of the phase modulation. When the subtraction value is positive and negative before and after this bit boundary, the wobble data A
In DIP, logic 1 and 0 can be determined. Incidentally, the subtraction value sandwiching one from the bit boundary is a value having no meaning. In this embodiment, since the bit inversion is always performed once in one address data block, the bit boundary can be reliably detected during a predetermined period.

In accordance with this detection principle, the decoder 192
Detects a bit boundary from the output data Δφ of the subtraction circuit 191. Further, the wobble data ADIP is decoded and output by judging the subtraction value Δφ every cycle based on the detected bit boundary. (FIG. 53
(G) and (H)).

According to the configuration of the third embodiment, the same effect as in the first embodiment can be obtained even if the wobble signal is meandered by phase modulation. Further, at this time, the timing ts corresponding to all the bit centers and bit boundaries of the wobble data ADIP
If the signal is averaged within one bit of the wobble data ADIP so as to cross 0 at tc and tc, a wobble signal can be generated so that the phase error becomes 0, thereby making it possible to average the frequency fluctuation and phase. A highly accurate clock with little fluctuation can be generated, and when recording user data at a correspondingly high density, the user data can be accurately recorded and the information recording surface can be used effectively.

(4) Other Embodiments In the above-described embodiment, the case of land / groove recording has been described. However, the present invention is not limited to this, and can be widely applied to land / groove recording. be able to.

In the above embodiment, the case where one groove is formed in a spiral shape has been described. However, the present invention is not limited to this, and one track is formed in a spiral shape by alternately switching between lands and grooves. The present invention can be widely applied to the case of forming on a substrate.

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.

Further, in the above-described embodiment, a case has been described where a single optical disk device accesses a magneto-optical disk, a phase-change optical disk, and a write-once optical disk, but the present invention is not limited to this. Any one type of optical disk may be configured to be accessible, and conversely, in addition to these optical disks, a DV
D, a compact disk, or the like may be configured to be accessible.

In the above-described embodiment, the track pitch is 0.5 μm 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 0.6 [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 [GB]
Capacity 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 modulating magnetic field is applied from the laser beam irradiation side to enable efficient thermomagnetic recording,
As a result, a capacity of 8 [GB] can be secured. By the way, the thickness of the light transmitting layer is important for protecting the information recording surface.
It is necessary to secure 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, and the linear recording density is 0.23 [μm / bit]. μm / bit], the same capacity as in the above-described embodiment can be secured. When this is converted into a bit length and a mark length, the shortest bit length and the shortest mark length 0.3 [μ
m] is an acceptable range. Incidentally, the present invention relates to 8-1
Modulation schemes such as 6 conversion can be widely applied.
According to -16 modulation, the maximum run length is 3T and the minimum run length is 1T. The shortest pit length and shortest mark length are as follows.
This is 3/2 bits.

In the above embodiment, the wavelength 6
Although the case where a laser beam of 50 [nm] is irradiated by an optical system having a numerical aperture of 0.78 to record and reproduce a video signal and the like has been described, the present invention is not limited to this, and the video signal is not limited to an optical system having a high numerical aperture. And the like can be widely applied when recording at high density. In consideration of the thickness of the light transmitting layer, the achievable working distance, and the like, when the numerical aperture is 0.7 or more, the working distance is 560 [μm] or less, and the wavelength of the laser beam is 680 [nm] or less, The same capacity as in the embodiment can be secured.

In the above 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.

[0333]

According to the above arrangement, the numerical aperture NA 0 .0 set to a working distance of 560 [μm] or less.
By accessing the optical disk by irradiating a laser beam having a wavelength λ of 680 [nm] or less with an optical system of 7 or more, it is possible to record 8 [GB] of user data. It is possible to secure a recording capacity that can effectively utilize the function and that can obtain the same usability as a video tape recorder.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an optical disc device according to a first embodiment of the present invention.

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

FIG. 3 is a plan view for describing zoning by the mastering device in FIG. 2;

FIG. 4 is a schematic diagram illustrating a configuration of a sector by zoning in FIG. 3;

FIG. 5 is a perspective view showing an optical disc generated by the mastering device of FIG. 3;

FIG. 6 is a block diagram mainly showing a drive system of the optical disk device of FIG. 1;

FIG. 7 is a schematic diagram illustrating an optical head of the optical disk device of FIG. 1;

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

FIG. 9 is a characteristic curve diagram showing a relationship between a working distance and a beam diameter.

FIG. 10 is a characteristic curve diagram for explaining the driving of the optical disk by the optical disk device of FIG. 6;

11 is a flowchart showing a processing procedure of a system control circuit in the optical disc device of FIG.

FIG. 12 is a table provided for explaining a sector structure in the optical disk device of FIG. 1;

FIG. 13 is a table showing ECC blocks in the optical disk device of FIG. 1;

FIG. 14 is a table provided for describing a frame structure in the optical disc device of FIG. 1;

FIG. 15 is a schematic diagram illustrating flows of a video signal and an audio signal of two channels in the optical disc device of FIG. 1;

FIG. 16 is a schematic diagram for explaining an operation in a normal recording / reproducing operation of the optical disk device in FIG. 1;

FIG. 17 is a schematic diagram for explaining the operation of the optical disc apparatus of FIG. 1 in chasing reproduction.

FIG. 18 is a characteristic curve diagram for explaining the driving of the optical disc when processing the two-channel video signal and the audio signal in the optical disc apparatus of FIG. 1;

FIG. 19 is a schematic diagram for describing an operation in a multi-channel mode of the optical disc device in FIG. 1;

FIG. 20 is a schematic diagram for explaining the operation of the optical disc apparatus of FIG. 1 in after-recording.

FIG. 21 is a block diagram illustrating a relationship with an external device during post-recording.

FIG. 22 is a schematic diagram used to explain an operation in reproducing a pointer of the optical disc device in FIG. 1;

FIG. 23 is a plan view for explaining access of the optical disc in each zone.

FIG. 24 is a characteristic curve diagram showing a relationship between dust and a burst error.

FIG. 25 is an exploded perspective view showing a cartridge of the optical disk applied to the optical disk device of FIG. 1, omitting a shutter.

26 is a plan view showing a relationship between an opening and a sheet-like member in the cartridge of FIG. 25.

FIG. 27 is a perspective view showing a relationship between the cartridge of FIG. 25 and a shutter and the like.

FIG. 28 is a plan view showing a relationship among a shutter, an opening, and a buffer member in the cartridge of FIG. 25.

FIG. 29 is a plan view for describing one movable restriction mechanism of the cartridge of FIG. 25;

FIG. 30 is a plan view showing a state where one button 70A is pressed in comparison with FIG. 29;

FIG. 31 is a plan view showing a state where another button 71A is pressed in comparison with FIG. 30;

FIG. 32 is a plan view showing a state where the shutter is moved in comparison with FIG. 31;

FIG. 33 is a plan view for explaining another movement restricting mechanism of the cartridge of FIG. 25;

34 is a plan view showing a state where one button 70B is pressed in comparison with FIG. 33. FIG.

FIG. 35 is a plan view showing a state where the shutter is moved in comparison with FIG. 34;

FIG. 36 is a perspective view showing a loading mechanism of the optical disc device.

FIG. 37 is a block diagram for explaining identification of an optical disk in the optical disk device.

FIG. 38 is a block diagram showing a mastering device according to a second embodiment of the present invention.

FIG. 39 is a table provided for describing wobble data by the mastering device of FIG. 38;

40 is a signal waveform chart for describing generation of a wobble signal by the mastering device of FIG. 38.

FIG. 41 is a signal waveform diagram showing a wobble signal generated by the mastering device of FIG. 38.

FIG. 42 is a block diagram showing an optical disk device for accessing an optical disk manufactured by applying the mastering device of FIG. 38;

FIG. 43 is a signal waveform diagram for describing generation of a clock by the optical disc device of FIG. 42;

FIG. 44 is a plan view for explaining driving of the optical disk by the optical disk device of FIG. 42K;

FIG. 45 is a chart provided for describing a frame structure in the optical disc device in FIG. 42K;

FIG. 46 is a chart provided for describing a cluster in the optical disc device of FIG. 42K;

FIG. 47 is a block diagram showing a mastering device according to a third embodiment of the present invention.

FIG. 48 is a table provided for explaining wobble data by the mastering device of FIG. 47;

FIG. 49 is a signal waveform diagram for describing processing of a wobble signal by the mastering device of FIG. 47;

50 is a block diagram showing an optical disk device for accessing an optical disk manufactured by applying the mastering device of FIG. 47.

FIG. 51 is a block diagram showing a wobble signal processing circuit of the optical disc device of FIG. 50;

52 is a signal waveform diagram for describing the operation of the wobble signal processing circuit in FIG. 51.

FIG. 53 is a signal waveform diagram showing a continuation of FIG. 52.

[Explanation of symbols]

1, 101, 161 mastering device, 2 disk master, 5 drive circuit, 6 address signal generation circuit, 7, 107, 167 wobble signal generation circuit,
10, 110, 170 ... optical disk device, 11 ... optical head, 12, 112, 172 ... optical disk, 17 ...
... Objective lens, 35, 135 ... PLL circuit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shinji Katsuramoto 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Toshio Watanabe 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo No. Sony Corporation (72) Inventor Hidenori Mori 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Inventor Masanobu Yamamoto 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Maki Saito 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation

Claims (15)

[Claims] An optical disk having an information recording surface formed on a substrate surface has a numerical aperture NA of 0.7 or more which is disposed on the information recording surface side and has a working distance of 560 [μm] or less. Of the wavelength λ is 68
An optical disk device for recording and / or reproducing desired user data by irradiating a laser beam of 0 [nm] or less. 2. The shortest pit length or the shortest mark length 0.3 [μ
[m] The optical disk device according to claim 1, wherein the user data is recorded and / or reproduced in the following manner. 3. The optical disk apparatus according to claim 1, wherein said user data is subjected to (1, 7) RLL modulation and recorded and / or reproduced at a linear recording density of 0.23 [μm / bit] or less. . 4. The optical disk device according to claim 1, wherein a track pitch of the optical disk is set to 0.6 [μm] or less. 5. A method for continuously inputting the user data to a buffer memory, intermittently recording the user data on the optical disk via the buffer memory, and controlling a data transfer rate of the user data when recording on the optical disk. 2. The optical disk device according to claim 1, wherein the optical disk drive is set to 11.08 [Mbps] or more. 6. A method for sequentially outputting the user data from a buffer memory, inputting the user data reproduced from the optical disk intermittently to the buffer memory, and outputting the user data when reproducing from the optical disk. 2. The optical disk device according to claim 1, wherein the data transfer speed is set to 11.08 [Mbps] or more. 7. The optical disk device according to claim 1, wherein redundant data is added to said user data and recorded on said optical disk with a redundancy of 23% or less. 8. The optical disk, wherein the light transmitting layer is set to have a thickness of 10 to 177 [μm], and the optical disk device sets the numerical aperture NA when a variation in the thickness of the light transmitting layer is Δt. 2. The optical disk device according to claim 1, wherein the wavelength and the wavelength λ are set so as to satisfy the following relational expression. Δt ≦ ± 5.26 × (λ / NA ⁴ ) [μm] 9. The optical disk, wherein the optical disk is stored and held in a predetermined cartridge, and wherein the optical disk device accesses the optical disk by rotating and driving the optical disk stored in the cartridge. 2. The optical disc device according to 1. 10. The optical disc, wherein a groove serving as a guide groove for the laser beam is formed in a meandering, helical or concentric manner, and the meandering cycle is sequentially from the inner circumference to the outer circumference of the optical disc. The optical disc device, wherein the optical disc device drives the optical disc by sequentially changing the rotation speed of the optical disc in a stepwise manner in accordance with the meandering cycle at the laser beam irradiation position. Item 2. The optical disk device according to item 1. 11. The optical disc, wherein a track serving as a guide groove for the laser beam is formed spirally or concentrically to form a track, and the optical disc device is configured to perform a recording operation based on address information recorded on the track. 2. The optical disk apparatus according to claim 1, wherein one round of the track is divided into a plurality of sectors, and the optical disk is accessed in units of the sectors. 12. The optical disk, wherein a groove for guiding the laser beam is formed in a spiral or concentric manner. The optical disk device is configured such that the user data is provided in a land and a land between adjacent grooves. 2. The method according to claim 1, wherein
An optical disk device according to claim 1. 13. A method for successively inputting the user data to a buffer memory, intermittently recording the user data on the optical disk via the buffer memory, and controlling a data transfer rate of the user data when recording on the optical disk. 2. The optical disk device according to claim 1, wherein the speed is higher than a data transfer speed input to the buffer memory. 14. A continuous output of the user data from a buffer memory, input of the user data reproduced from the optical disk intermittently into the buffer memory, and reproduction of the user data from the optical disk and input to the buffer memory. 2. The optical disk device according to claim 1, wherein a data transfer speed of the user data is higher than a data transfer speed output from the buffer memory. 15. The user data is divided into blocks in predetermined block units, an error correction code is added in units of each block, and the user data is recorded and reproduced on the optical disk in units of blocks. 2. The optical disk device according to claim 1, wherein the unit is set to 32 KB or more.