JP2003331420A - Optical disk control system and optical disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk on which control data intrinsic thereto are recorded without using a marking device and to provide a control system therefor. <P>SOLUTION: The optical disk is formed by adhering a layered substrate formed sequentially with recording films and spiral grooves on a light transmission substrate to a dummy substrate with the thickness and diameter the same as those of the layered substrate via an adhesive in a manner that the recording film is placed confronting to the dummy substrate. On the data area of the optical disk, a non-initializing area and an initializing area are sequentially formed by a prescribed length along a circumferential direction of the data area of the optical disk. The optical disk management system manages data intrinsic to data of the optical disk by detecting light reflected in a non- initializing area and an initializing area respectively as particular patterns on the basis of a variation in the reflectance when irradiating the data area with reproduction laser beam. The length of the initializing area and the non- initializing area are selected to be 10 μm to 100 μm being twice or more than the longest recording mark length of the recording mark. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk management system and an optical disk for managing recording / reproduction of a disk by using management data unique to the disk.

[0002]

2. Description of the Related Art Conventionally, an optical disc management system assigns a management number to each disc and manages a large number of discs using this management number as a key, and also records a large amount of software information (content information). In order to charge for reading the specified content information by playing the recorded disc, the management number and the content information to be played are linked to accurately specify the charged content information, In order to prevent the illegal copying of the disk, there is a disk system in which the authenticity of the disk is discriminated by the presence / absence of the management number.

[0003]

In the above-mentioned disk system, since a different management number must be given to each disk, from the viewpoint of the disk manufacturer, the number of man-hours and the cost for manufacturing the disk are reduced. There was an additional drawback. This will be described with an example.

For example, as a new high density optical disc,
DVD using a red laser beam with a wavelength of around 630 nm
(Digital Versatile Disc) has appeared. This DVD is a read-only disc, DVD-ROM
Has a merit that a minute information signal (signal track) is engraved on a disk substrate having a thickness of 0.6 mm, and has an advantage that it can be reproduced in a large amount. The DVD having such a shape has a BCA (burst cutting area) standard as one of the DVD standards.

BCA is a disc that corresponds to a different management number for each disc in a specific region (BCA region) of the disc substrate of the DVD after completion of the DVD by using a high-power laser beam such as a YAG laser. Burn out in a bar code pattern that is linear in the diameter direction. In this way, a different management number is assigned to each DVD. After that, when the DVD is reproduced, by irradiating the reproducing laser beam on the BCA code in the BCA area of the disc substrate, the amount of reflected light reflected from the BCA code largely changes in a bar code pattern (from a portion which is not burned out). The amount of reflected light (reflectance) is large, whereas the amount of reflected light (reflectance) from the burned-out part is small). Different control numbers can be detected.

However, in the system using the above-mentioned BCA standard, when the disc is manufactured, the BC is newly added.
Since it is necessary to purchase an A stamping machine, it has a drawback of increasing the production cost. It also has the drawback of increasing the number of steps for marking.

On the other hand, the above-mentioned BCA is a DVD
-ROM, but other DVDs (DVD-R, D
Recordable DV such as VD-RW, DVD-RAM)
It is also valid for D. However, in a recordable DVD, a recording condition test area (recording or reproduction laser light output is a default value) peculiar to a recordable DVD is located at a recording start radial position of the disc where the BCA marking machine is effective. Areas for testing whether there is, for example, PCA (power calibration area), RMA (recording management area), etc.)
However, if the BCA code described above is recorded in this test area, the recording condition test cannot be performed, and it is impossible to engrave the BCA code (that is, a different management number for each DVD). Further, even if such a recording condition test area is moved to another place, the cost disadvantage that the BCA stamping machine described above must be purchased and the drawback that the number of processes is increased can be solved. I haven't arrived.

Therefore, the present invention has been made in order to solve the above-mentioned drawbacks, and when initializing a phase change optical disk, management data specific to the disk is recorded when the data is recorded after the initialization. By providing an optical disc management system that manages recording / reproduction of the disc by using the management data, the management data peculiar to the disc can be recorded on the disc without using the marking machine. The purpose is to give.

[0009]

In order to solve the above problems, the present invention provides an optical disk management system and an optical disk having the following configurations (1) and (2). (1) An adhesive is applied to a laminated substrate in which a spiral groove having a predetermined track pitch and a recording film are sequentially formed on a light transmissive substrate, and a dummy substrate having the same thickness and diameter as the laminated substrate. An uninitialized area and an initialized area are sequentially formed at least with a predetermined length along the circumferential direction of the data area of the optical disk that is bonded so that the recording film faces the dummy substrate. When the data area is irradiated with a reproducing laser beam, the optical disk-specific management is performed by detecting the reflected light reflected from each of the uninitialized area and the initialized area as a specific pattern based on reflectance variation. In the optical disc management system, the length of the initialized area and the uninitialized area is at least twice as long as the longest recording mark length of the recording mark. Optical disc management system, which is a M～100myuemu. (2) An adhesive is applied to a laminated substrate in which spiral grooves having a predetermined track pitch and a recording film are sequentially formed on a light transmissive substrate, and a dummy substrate having the same thickness and diameter as the laminated substrate. An uninitialized area and an initialized area are sequentially formed at least with a predetermined length along the circumferential direction of the data area of the optical disc formed by laminating the recording film so as to face the dummy substrate. An optical disc, wherein the lengths of the uninitialized region and the initialized region are 10 μm to 100 μm, which is at least twice the length of the longest recording mark of the recording mark.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The optical disc management system and optical disc of the present invention will be described below.

FIG. 1 is a diagram for explaining an optical disc recording / reproducing apparatus used in the optical disc management system of the present invention, and FIGS. 2 and 3 are diagrams for explaining a state after initialization of the optical disc of the present invention, respectively. FIG. 4 is a reproduction output waveform diagram when the optical disc of the present invention is in a non-recorded state after initialization, FIG. 5 is a reproduction output waveform diagram of the optical disc of the present invention at the time of initial recording, and FIG. 6 is an optical disc of the present invention. FIG. 7 is a signal output waveform diagram in which a reflectance signal is extracted, FIG. 7 is an envelope detection output waveform diagram, FIG. 8 is a diagram showing a main part of a signal processing circuit, and FIG. 9 is a diagram illustrating an example of initialization of the optical disc of the present invention. Is.

The present inventors have studied the above-mentioned BCA code, which is a method of giving different management numbers to each disc, and whether it can be applied to a recordable disc more easily. The invention can be disclosed.

First, in order to explain the optical disc of the present invention, as an example, PD, CD-RW, DVD-RAM,
A method of manufacturing a recordable optical disc used for a series of phase change recording media such as a DVD-RW will be described. In this description, the effectiveness of the present invention will also be described. These recordable optical discs are manufactured by taking the same steps as those of the read-only optical disc, which is a DVD-ROM, up to the intermediate steps. (Optical Disc Manufacturing Method) (1) First, a glass plate coated with a thin resist on its entire surface is irradiated with a cutting laser beam from a cutting machine to form a spiral groove with a predetermined track pitch. Record formation. (2) Next, a spiral groove is deposited on the glass plate as a change in shape through a developing process. (3) Next, a thin nickel conductive film is formed on the resist-coated glass master plate, nickel plating is performed in a wet nickel plating bath, and the finished nickel plate is cut into a predetermined size to be molded. Obtain a metal master. (4) Next, a mold for optical disk molding is mounted on the injection molding machine, the metal master described above is mounted in the mold, and polycarbonate resin or the like is injection molded to obtain a disk substrate. The disk substrate usually has a diameter of 120 mm, and is a CD-RW
If so, the thickness is 1.2 mm, DVD-RAM, DVD
With -RW, the thickness is 0.6 mm. A spiral groove is formed on the surface of the molded substrate. (5) Next, there is a step of applying a recording film on the molded disc substrate. The disk substrate is placed in a vacuum film forming apparatus to apply a recording film. CD-RW, DVD-RA
In M, DVD-RW, etc., a dielectric film containing zinc sulfide as a component is formed as a first layer in contact with the disk substrate in a vacuum film forming apparatus. Then, a recording film containing antimony, tellurium or the like as a second layer is formed on the first layer. (6) Next, a dielectric film containing zinc sulfide or the like is again formed as a third layer on the recording film. Then, a metal reflective film such as aluminum is formed as a fourth layer on the third layer. In this manner, the dielectric film, the recording film, the dielectric film, and the metal reflection film are sequentially laminated on the disk substrate to complete the disk. (7) After that, for the purpose of increasing the sensitivity of the recording film and improving the performance of repeated recording, in addition to these four layers, the first layer and the second layer
A new layer may be provided between the layers or between the second layer and the third layer, or between the third layer and the fourth layer, and may have a five-layer structure or a six-layer structure as a whole. Furthermore, in the case of a dual layer recording DVD-RAM for the next generation high density recording optical disc, the fourth
In some cases, the metal reflection film of the layer is not used, or instead, a semiconductor such as silicon carbide having good thermal conductivity and high permeability is formed in the fourth layer. (8) After the recording film is formed, in the case of a single plate type optical disc such as a CD, a protective film made of an ultraviolet curable resin is applied on the recording film to a thickness of about 5 μm, and the ultraviolet rays are irradiated. The cured resin is cured to form a protective film. Then, a label layer is formed on the protective film. The label layer prints, for example, characters such as "CD-RW" as the content information of the disc and the manufacturer name. Also, DV
In the case of a bonding type such as D, a disk substrate (also called a dummy disk) having the same diameter and the same thickness as the disk disk on which the recording film is formed is prepared and used as an adhesive on the recording film, for example. Apply UV curable resin, stack dummy boards, and stick them together using a spinner (2P
Law). (9) After the bonding, the surface of the disk adhesive is irradiated with ultraviolet rays in order to cure the ultraviolet curable resin which is the adhesive. After that, a label is printed on the non-reproduction surface side (dummy board side) of the disc. Furthermore, blue laser light (wavelength 400n
m) is a next-generation high-density disc typified by an optical disc for recording / reproducing, and if the high-density disc has a numerical aperture of about 0.8 of the objective lens of the optical head, for example, the above-mentioned injection molding A disc is obtained by forming and forming each functional film on the formed disc substrate (substrate thickness 1.2 mm) in the reverse order of the above. That is, on the injection-molded disk substrate, the above-mentioned fourth layer, the reflection film, is first formed, then the third layer, the dielectric layer, the second layer, the recording film, and finally the first layer. It is created by sequentially forming a dielectric layer which is a layer. Then, for example, an ultraviolet curable resin is applied by a spinner to a thickness of about 0.1 mm on the dielectric layer which is the first layer formed at the end and is cured by ultraviolet rays to be a read / write surface for recording and reproduction. Is. In this case, the label area of the disc is on the surface of the previously injection-molded substrate on which the spiral recording groove is not formed.

The recording type optical disk produced by the above procedures (1) to (9) is next initialized with a recording film.

In the initialization of the recording film, if the recording film is still formed, the recording film is in an amorphous state (amorphous state) and good recording cannot be performed. Therefore, good recording can be performed by irradiating the entire surface of the recording film with a high-output initialization laser beam and performing initialization for crystallizing the recording film in an amorphous state by heat of the laser beam. . In the initialized data recording area, when the area is irradiated with a reproducing laser beam, the reflectance is generally improved as compared with the uninitialized area. Since this reflectance increases as the laser beam with a larger output is emitted at the time of initialization, the recording conditions for recording information change significantly depending on this initialization condition (the size of the output laser beam for initialization). To do. By performing such initialization of the recording film, the recording type optical disk has a recording function for the first time. In the present invention, this initialization step is described as being performed before label printing, but it may be performed after label printing.

Information can be recorded for the first time on the initialized recordable optical disk. Recording of information is performed by a recorder (not shown), and when a recording laser beam is irradiated onto the initialized recording film of the recording type optical disc to record information, the recording film in a crystalline state is in an amorphous state. A place (mark) that is fixed by and has a lower reflectance than the surrounding (space) in a crystalline state is formed, and becomes information called a mark. On the other hand, when the recording laser beam is not irradiated, there is no change in the recording film, the same reflectance as that at the time of initialization is maintained, and it becomes information called space. When rewriting the information on the recording film on which the mark is formed, the overwrite recording condition is applied. This overwrite recording condition means that the recording film once undergoes various processes after reaching the crystallization temperature, and is rewritten into a mark or a space under the output conditions of the recording laser beam at the time of recording. Has been.

In the process of initializing the recording film, it suffices to simply apply heat with a laser beam.
It is characterized in that the recording characteristics of the recordable optical disc greatly change depending on how the heat is applied. The present invention was made by paying attention to the fact that the recording characteristics of the disc change depending on the initialization conditions of the recording film.

As described above, satisfactory information cannot be recorded unless the recording film of the phase-change recording disc, which is the above-mentioned recording-type optical disc, is initialized. A recorder (not shown) for recording data on such a phase change recording disk is designed so that the intensity of the recording laser beam at the time of recording and the irradiation time of the laser beam are adjusted so that a satisfactory recording state can be obtained on the phase change recording disk. And are predetermined. The predetermined laser beam recording conditions are the conditions in the laser recording sequence stored in the storage circuit (memory) built into the recorder, and the optimum recording conditions for each disc are stored in advance. It is the condition when recording is performed by following the recording sequence of the laser recorded inside.

Since the recording conditions in such a recording apparatus are determined on the assumption that the disc has already been initialized, if the disc is not initialized, it is sufficient on the recording film of the disc. The state is not recorded. That is, the output power of the initialization laser beam used for initialization is higher than the output power of the recording laser beam used for recording. For this,
If there is an uninitialized area on the disc, the uninitialized area will be initialized even if the optical disc is rewritten many times with a recording laser beam (when repeatedly recorded). It shows that the position and length information of places that are not open are kept for a long time.

Similarly, the initialization laser beam is irradiated in excess of the irradiation intensity at the time of normal initialization to perform excessive initialization (initialization with a power of 1.5 to 2 times the proper power). Even if the data is recorded on the disc after the step (a), the reflectance cannot be sufficiently reduced so that the data can be recorded well, and the recording cannot be performed satisfactorily. This state is characterized in that this state is maintained even after the data is rewritten many times on the disc. Therefore, in order to perform good recording on the entire surface of the disk (for example, data recording area), the initialization conditions (output intensity of the initialization laser beam, irradiation power) must be uniform on the entire surface of the disk. . Here, the outputs of various laser beams are compared as follows.

Excessive initialization laser beam output> Ordinary initialization laser beam output> Recording laser beam output> Reproducing laser beam output The optical disc management system of the present invention uses the initializing conditions (initializing laser beam We actively use the phenomenon that if the irradiation intensity is different, this difference in the initialization condition will remain without disappearing even if the information is rewritten on the disc many times.
It is used for recording the above-mentioned optical disc management number (ID code).

As a first embodiment of the optical disk management system of the present invention, information of a management number peculiar to the disk is recorded as a unique pattern based on fluctuations in reflectance during one round of the disk. For example, the position on the disc that has not been initialized and its length, or the position on the disc that has been excessively initialized (initialized with 1.5 to 2 times the power as appropriate). If the disc and its length are made different for each disc, it is possible to make a management number peculiar to the disc by using the position and the length as information.

However, even if the initialization is performed excessively, if the initialization laser irradiation light intensity is so large that the recording spiral groove (groove) is deformed, the tracking guides adjacent to both sides of the recording spiral groove are formed. Since the groove for use is deformed and satisfactory tracking cannot be obtained at the time of recording information, excessive initialization must be performed within a range in which the shape of the groove is not deformed. If you try to record information on a disc if there is a location that has not been initialized or a location that has been over-initialized in this way, the location that has not been initialized will be the location that is being initialized. The reflectance is low compared to. As a result, the fluctuation of the reflectance during one round of the disk has a peculiar pattern. By detecting this peculiar pattern, it becomes possible to read the information of the disc management number.

More specifically, during recording, the output fluctuation of the push-pull signal for obtaining the tracking error detection signal (that is, the output fluctuation of the push-pull signal obtained from the disc on which the information of the disc management number is not recorded). It is possible to read the information of the disc management number by detecting (for example, envelope detection) that the size is significantly larger or smaller than that. Therefore, even when recording for the first time on an unrecorded disc, the management number can be read from the tracking signal.

A second embodiment of the optical disk management system of the present invention is an extension of the above-mentioned first embodiment, and initialization conditions (irradiation intensity of initialization laser beam) are used.
By using the phenomenon that the recording condition of the disc changes depending on the disc, the scanning position of the initialization laser beam partially overlaps (that is, it is initialized once and then further initialized), and the information of the management number unique to the disc Is recorded as a peculiar pattern based on the reflectance fluctuation during one round of the disc. For example, generally, the spot shape of the initialization laser beam on the disk is a strip shape extending in the diameter direction of the disk. It is widely adopted because it is possible to initialize several tracks at a time by using a laser beam extending in a strip shape in the diameter direction while rotating the disk, and it is possible to improve the efficiency of initialization.

When a laser beam for initialization having such a shape is used, if a strip-shaped end is set to overlap when the next disk rotation period comes, a track is initialized twice. Since it has been performed (that is, initialized once and then further initialized) and the initialization state is different from other tracks, when recording information on the disc,
The track that has been initialized twice shows a peculiar phenomenon such that the output signal at the time of disc reproduction becomes larger or smaller than the other tracks. At this time, by adjusting the laser beam for initialization to the rotational speed of the disk, or by making a minute fluctuation in a specific cycle in the diameter direction of the disk according to the linear velocity at the time of initialization of the disk,
After recording the information on the disc and playing the recorded information,
It can be seen that the output of the reproduction signal is amplitude-modulated in the fluctuation cycle of the initialization laser beam when the disk is initialized.
By extracting the amplitude-modulated reproduction output fluctuation by envelope detection, it is possible to use the disc management information. Also in this case, the output fluctuation of the reproduced signal does not change even after the information on the disc is rewritten many times, and therefore it is optimum as the management information.

Specific examples of the first and second embodiments of the optical disc management system of the present invention described above are as follows.
That is, as shown in FIG. 2, on each track (spiral groove) g on the data area De of the optical disc D1, the uninitialized area a, the proper initialized area b, and the excessive initialized area c are alternately arranged in the radial direction. Are formed with the same length. Since the optical disc D1 shown in FIG. 2 is a CLV (constant linear velocity) type disc, the uninitialized region a, the proper initialized region b, and the excessive initialized region c are on the same line (at the same position) in the radial direction. Absent. Further, as shown in FIG. 3, on the data area De of the optical disc D2, an uninitialized area a, an appropriate initialized area b,
Excessive initialization regions c are formed alternately in the radial direction and have the same length. The optical disc D2 shown in FIG.
Since it is an AV (constant angular velocity) type disk, the uninitialized area a, the proper initialized area b, and the excessive initialized area c are on the same line (same position) in the radial direction. In this way, over the entire surface of the optical disc D, a specific pattern using the uninitialized region a, the proper initialized region b, and the excessive initialized region c is formed according to the disc-specific management number. As a result, the reproduced waveform based on the reflected light obtained by irradiating the initialized optical discs D1 and D2 with the normal recording laser beam or the reproducing laser beam is shown in FIG.
As shown in FIG. In FIG. 4, a waveform portion a1 indicates a reproduction signal output based on the reflected light obtained by irradiating the uninitialized area a of the disks D1 and D2 with a normal recording laser beam or a reproducing laser beam. Similarly, the waveform portions b1 and c1 show the reproduced signal output based on the reflected light in the proper initializing region b and the excessive initializing region c, respectively.

Further, FIG. 5 shows that the initial recording of data is performed on the unrecorded area a, the proper initialization area b, and the excessive initialization area c of the optical discs D1 and D2 by using a normal recording laser beam after the initialization. The reproduced signal output based on the reflected light at the time of performing is shown. In FIG. 5, the waveform portion a2 is the optical disc D.
Data is recorded by irradiating a normal recording laser beam on the unrecorded areas a of D1 and D2, and the reproduced signal output based on the reflected light obtained by this is shown. Similarly, the waveform portions b2 and c2 are respectively the proper initialization region b,
The reproduction signal output based on the reflected light from the excessive initialization area c is shown.

Further, as a third embodiment of the optical disk management system of the present invention, by varying the output of the initialization laser beam, the information of the management number peculiar to the disk is caused by the unevenness of the initialization state during one round of the disk. It is recorded as a peculiar pattern based on the reflectance variation of the reflectance that occurs.

Furthermore, as a fourth embodiment of the optical disk management system of the present invention, the rotation speed of the disk may be changed at the time of initialization without changing the output of the initialization laser beam. By stopping the rotation of the disk for a moment, the information of the management number peculiar to the disk is recorded as a peculiar pattern based on the reflectance fluctuation of the reflectance caused by the unevenness of the initialization state during one round of the disk. The series of operations has a feature that the management information in the disc can be read by recording the information signal on the disc by changing the disc initialization condition in the disc rotation direction.

The following are specific examples of the third and fourth embodiments of the optical disc management system of the present invention described above.
That is, as shown in FIG. 9, the output of the initialization laser beam is periodically and continuously varied and initialized on each track (spiral groove) g on the data area De of the optical disc D3.
In this way, the conditions at the time of initialization are changed. Figure 9
The shaded area in the middle indicates the area that is difficult to initialize.

Furthermore, as a fifth embodiment of the optical disc management system of the present invention, there is the following. That is, the recorded data information has a place where it can be recorded in two places inside the spiral groove and outside the groove like a DVD-RAM, which is called a land-groove recording method. Then, there are two types of methods such as a groove recording method for recording record information in a spiral groove as represented by CD-RW or DVD-RW. The method described below is a method capable of producing a particularly good effect in the groove recording method.

First, at the stage of the initialization step, one track or several tracks of the spiral groove (groove) is not initialized or is excessively initialized. Or 1
It may be possible not to intermittently initialize the area within the track or to initialize it excessively. Then, when information is recorded in this state, a recording mark that is more satisfactory cannot be formed as compared with a groove that is normally initialized, but some recording is possible. However, marks are hard to be formed in a place outside the groove (specifically, in a land) where recording is not sufficiently performed, so that the reflectance remains low or high. In such a track, even if rewriting is performed many times, the land portion is not sufficiently recorded, so that the land portion has a low reflectance or a high reflectance. When such a track is reproduced, a reproduction output different from that of other tracks is obtained. For example, when an uninitialized track is played, a relatively large playback output and a signal in which the playback output of the mark and space are inverted are obtained, and the initialized location is a relatively small signal output, Normal reproduction of marks and spaces can be obtained.

In the case of excessive initialization, marks are not normally formed during recording, so that a smaller signal output can be obtained. Therefore, if envelope detection is performed on the playback output, envelope detection output corresponding to changes in the initialization conditions will be obtained.If the cycle or time of the initialization presence / absence region is used as information, the envelope detection output will be It becomes possible to retrieve the information. It is also possible to use it as an information signal by detecting not the envelope detection but the DC component as the reflectance component of the output from the optical head. Further, the same effect can be obtained by changing the laser beam output at the time of initialization within the track, regardless of whether or not the initialization change region is present.

The fluctuation of the initialization condition is preferably set to a cycle of, for example, 10 kHz or more so as not to affect the tracking performance of the recorder when recording information on the disc by the disc recorder. It is desirable that the length is at least twice as long as the longest recording mark length of the recording mark, for example, 10 μm or more so as not to interfere with the reproduction mark information.

The signal output obtained from the optical head is obtained by the detection method as shown in FIGS. 6 and 7, and the desired signal processing is performed by introducing the output to the comparison circuit having the configuration shown in FIG. You can do it. The information obtained by this signal processing (detecting the envelope detection signal output at the three levels a4, b4, c4) can be used as key information for reproducing the optical discs D1, D2. I can.
For example, a disc for which this key information cannot be obtained is discriminated as an illegally duplicated disc, and the disc is managed so that it cannot be recorded or reproduced.

That is, the reproduced signal output waveform has a stepped shape as shown in FIG. In FIG. 6, a waveform portion a3 represents a reproduction signal output (reflectance signal) based on the reflected light obtained by irradiating the unrecorded area a of the optical discs D1 and D2 with a normal recording laser beam or a reproducing laser beam. ing. Similarly, the waveform portions b3 and c3 show the reproduced signal output based on the reflected light of the proper initializing region b and the excessive initializing region c, respectively.

FIG. 7 shows an envelope detection signal output waveform obtained by envelope detection of the reproduction signal output waveform shown in FIG. The reproduction signal output based on the reflected light when the first data recording is performed after the initialization by using a normal recording laser beam is shown in the excessive initialization area c. In FIG. 7, the waveform portion a4 indicates the envelope detection signal output obtained by performing the envelope detection of the above-mentioned waveform portion a3. Similarly, the corrugated portions b4 and c4 are respectively corrugated portions b3 and c3.
The envelope detection signal output obtained by performing the envelope detection of is shown.

The comparison circuit 10 having the structure shown in FIG.
Is the reflectance signal (waveform portions a3, b3, c3 (FIG. 6))
Is a circuit for carrying out envelope detection to read out key information a5, b5, c5, input terminal 10a to which reflectance signals a3, b3, c3 are supplied, envelope detection circuit 10b, signal DC output or envelope detection. Envelope detection output a4 of circuit 10b
Switch 10c and switch 10c for selecting b4 and c4
10d and the reference voltage E are supplied to output the key information c5, and the output of the switch 10c and the voltage obtained by dividing the reference voltage by the resistors R1 to R3 are supplied to output the key information b5 and a5, respectively. Comparator 10e, 1
It is composed of 0f.

Various information can be recorded in the disc by changing the intensity of the initialization laser beam when the disc is initialized and the irradiation position on the disc, and the information is the information of the disc. Does not disappear even if it is rewritten, so that it becomes possible to use the management number for each disc or the key information for decrypting the information in the disc. Also, since this information can be dealt with in the disk initialization device, there is no need to purchase a new information recording device, no additional process for recording the information, and high quality at low cost. It is possible to assign different management numbers to the optical disc.

Next, specific examples of the optical disk of the present invention will be described. (Example 1) A guide groove was previously formed (track pitch 0.74 μm, groove depth 30 nm).
A 0.6 mm thick polycarbonate disk substrate is spun at 60 rpm while planetary rotation is performed.
Vacuum deposition was performed in which the first dielectric layer (dielectric film), the recording layer (recording film), the second dielectric layer (dielectric film), and the reflective layer (reflective film) were laminated in this order.

Specifically, it is as follows. (1) First, 6 × 10 in the vacuum chamber^-FiveExhausted up to Pa
1.6x10 after being aware ^-1Ar gas of Pa was introduced. (2) Next, SiO₂ZnS containing 20 mol% of
The film thickness is 71 on the substrate by the high frequency magnetron sputtering method.
nm first dielectric layer was formed. (3) Subsequently, 4 elements consisting of Sb, Te, Ag and In
A single target is sputtered with a DC power supply and the film thickness is 20 nm.
Recording layer was formed. The composition of the obtained recording layer was Ag._{twenty one}
In₆Sb₆₃Te₂₉Was (at%). (4) A second layer made of the same material as the first dielectric layer
A dielectric layer, which is a layer, is formed to a thickness of 17 nm, and Al-T is formed on the dielectric layer.
Direct sputtering of a two-element single target consisting of i
And the composition Al_98.2T1_1.8(At%) thickness 150 nm
The reflective layer of was formed. (5) From the vacuum chamber
After taking it out, an acrylic UV-curing resin was placed on this reflective layer.
Spin coating of grease (Sumitomo Chemical XR11) and UV irradiation
Harden by spraying to form a protective resin layer with a thickness of 6 μm
An optical recording medium of the invention was obtained. Use screen printing method
And apply a slow-acting UV-curing resin on the protective film,
The formed discs are stuck together, pressed and cured to allow double-sided
A disk was made.

Initialization was performed on the optical disk thus manufactured by using an initialization device as shown in FIG. Initialization device A
Has a disc rotating device 1 for rotating the optical discs D1 to D3, and the device 1 sends information about the number of revolutions to the initialization control device 2. The initialization laser beam irradiation device 3 incorporates the initialization laser beam L,
The light intensity information of the laser beam L and the radius information of the optical disc D irradiated by the laser beam L are sent to the initialization condition control device 2. The shape of the initialization laser beam L is a spot shape in which the beam width in the track direction is narrower than that in the radial direction (beam shape = tangential direction 1 μm × radial direction 20).
irradiating a wide beam laser beam
The recording film was heated above the crystallization temperature to carry out the initialization process.

The optical discs D1 to D3 were rotated at a linear velocity of 2 m / s, and the entire surface of the disc was initialized from the inner circumference to the outer circumference at a feed rate of 10 μm per revolution. The initialization laser beam output was set to the optimum power of 120 mW. At this time, the innermost peripheral portion of the disk D is not initialized but is left in an amorphous state as it was at the time of film formation, and the initialization laser beam L is modulated based on the information from the initialization condition controller 2 to control the number. Was recorded. The recording of the management number peculiar to the disk is performed at a linear velocity of 1 m / s, with the output of the initialization laser beam L set to an excessive 160 mW, and due to the fluctuation of the initialization conditions,
10 to 50 kHz (20 μm in length) so that the disk recorder does not affect the tracking state during disk playback.
~ 100 μm) on-off the initialization laser beam
Thus, a region in which radial crystallized portions and amorphous portions were mixed was formed in the radial direction.

The optical discs D1 to D3 have a wavelength of 639n.
Recording and reproduction were performed using an optical disk drive tester (DDU1000) manufactured by Pulstec Co., Ltd. equipped with a laser diode of m and an objective lens having a numerical aperture NA = 0.60. Recording was performed from the disk substrate side into a guide groove (the groove is convex when viewed from the incident direction of the laser beam). In the management number area, the recording layer is transferred to the crystallized state at a portion irradiated with the initialization laser beam L, and the reflectance is high, and the unirradiated portion remains in an amorphous state and has a low reflectance.
Since there is a reflectance variation, the reproduction output (a1) of the uninitialized area at the time of unrecording as shown in FIG. 4 and Table 1 is 0.14 V as the reproduction signal output variation, and the reproduction output of the proper initialization area ( b1) is 1.05 V, and the reproduction output (c
1) was 1.35V. The output fluctuation amount is the reproduction output (a1) of the uninitialized area and the reproduction output (b) of the proper initialization area.
1) or divided by the reproduction output (c1) of the excessive initialization region, and the value was about 0.10 to about 0.13.

[0046]

[Table 1]

When a recording operation was performed on the disc in such a state, as shown in FIG. 5 and Table 2, the reproduction output (a2) of the uninitialized area was 0.17 V, and the reproduction output of the proper initialized area. (B2) is 1.17V, and the reproduction output (c2) in the excessive initialization area is 1.31V. At this time, as for the output fluctuation amount, the reproduction output of the uninitialized area (a2) is the reproduction output of the proper initialization area (b2) or the reproduction output of the excessive initialization area (c).
Divided by 2), from about 0.13 to about 0.15
Became the value of.

[0048]

[Table 2]

(Embodiment 2) The optical disc D manufactured in the same manner as in Embodiment 1 was initialized under the optimum conditions described above, and then excess power was superposed on the initialized portion to record the management number information. The optical discs D1 to D3 were rotated at a linear velocity of 2 m / s, and the entire surface of the disc was initialized from the inner circumference to the outer circumference at a feed speed of 10 μm per revolution by the initialization condition device 2 equivalent to that of the first embodiment. The initialization laser beam output was set to 120 mW which is the optimum power. Then, in the control number area, the rotation speed is 1 m / s, and the initialization laser beam output is set to an excess of 160 mW in the proper initialization portion,
The initialization laser beam was turned on-off at 50 kHz, and the radial crystallized portion having a high reflectance and the radial crystallized portion having a low reflectance were mixedly formed. The portion of the recording layer that has been excessively irradiated with the initialization laser beam L has a high crystallinity, and the reflectance is higher. On the other hand, the portion of the recording layer that has been irradiated with appropriate power has the crystallinity of the crystalline state. And the reflectance is low. It was possible to read the control number information as the reflectance fluctuation.

When recording is performed in this area using a predetermined strategy, satisfactory recording cannot be performed in a portion where the initialization laser beam L is excessively irradiated, and good recording is obtained in a portion where a proper power is irradiated. It was possible. Even after the recording, the portion irradiated with the excessive power had a high reflectance, and the reflectance fluctuated. Therefore, it was possible to read the management number information from the variation of the amplitude amount of the reproduced signal.

[0051]

As described above, according to the present invention, there is provided an optical disc management system capable of imparting disc-specific management data to a disc without using a marking machine as in the conventional disc system. be able to.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an optical disc recording / reproducing apparatus used in an optical disc management system of the present invention.

FIG. 2 is a diagram for explaining a state after initialization of the optical disc of the present invention.

FIG. 3 is a diagram for explaining a state after initialization of the optical disc of the present invention.

FIG. 4 is a reproduction output waveform diagram in a non-recorded state after initialization of the optical disc of the present invention.

FIG. 5 is a reproduction output waveform diagram at the time of initial recording of the optical disc of the present invention.

FIG. 6 is a signal output waveform diagram in which a reflectance signal is extracted from the optical disc of the present invention.

FIG. 7 is an envelope detection output waveform diagram.

FIG. 8 is a diagram showing a main part of a signal processing circuit.

FIG. 9 is a diagram illustrating an example of initialization of the optical disc of the present invention.

[Explanation of symbols]

1 disk rotation device 2 Initialization condition controller 3 Initialization laser light irradiation device a to c specific pattern D1 to D3 phase change type optical disks, optical disks De data recording area L initialization laser beam

Continued front page    F-term (reference) 5D029 PA03 RA23 RA47                 5D090 AA01 BB05 CC01 CC04 CC11                       CC14 CC18 EE01 FF09 FF24                       GG16 GG32 GG38 JJ11

Claims (2)

[Claims] 1. A laminated substrate in which a spiral groove having a predetermined track pitch and a recording film are sequentially formed on a light transmissive substrate, and a dummy substrate having the same thickness and diameter as the laminated substrate are bonded together. An uninitialized area and an initialized area are sequentially formed at least with a predetermined length along the circumferential direction of the data area of the optical disk formed by bonding the recording film to the dummy substrate so as to face the dummy substrate via a chemical. When the data area is irradiated with a reproducing laser beam, the reflected light reflected from each of the uninitialized area and the initialized area is detected as a specific pattern based on the reflectance variation, thereby managing the optical disk uniquely. In the optical disc management system, the length of the initialized area and the uninitialized area is not less than twice the longest recording mark length of the recording mark. 10 μm
An optical disc management system characterized in that 2. A laminated substrate, in which a spiral groove having a predetermined track pitch and a recording film are sequentially formed on a light transmissive substrate, and a dummy substrate having the same thickness and diameter as the laminated substrate are bonded together. An uninitialized area and an initialized area are sequentially formed at least with a predetermined length along the circumferential direction of the data area of the optical disk formed by bonding the recording film to the dummy substrate so as to face the dummy substrate via a chemical. The length of the uninitialized area and the initialized area is 10 μm, which is at least twice the longest recording mark length of the recording mark.
An optical disc having a thickness of up to 100 μm.