JP2007048413A - Reproducing device, reproducing method, recording device, recording method, optical disk manufacturig method, and optical disk recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to determine that a disk, which is manufactured by physically transferring the forms of pits and lands formed on a substrate of an optical disk recording medium, is a pirated disk. <P>SOLUTION: This is an optical disk recording medium to which subdata are recorded by means of marks formed on a reflection film by the irradiation with laser beams by recording power. In this case, the marks are recorded according to the sizes and depths of the marks, which increase a reproduction signal level at a mark-forming part and decrease a reproduction signal level at a mark-forming part of a pirate disk. By this, the polarities of the reproduction signals at the mark-forming parts of a legitimate disk and pirated disk become different from each other. Further, the subdata of the optical disk recording medium are detected, and whether the values of the subdata thus detected are reproduced in adequate polarities is determined, and then whether the optical disk recording medium is a legitimate disk or a pirated disk is determined based on the result of the determination. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention is formed by laminating a substrate and at least a reflective film and a cover layer on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate, and a laser by recording power. An optical disc recording medium on which sub-data is recorded by marks formed on the reflective film by light irradiation, wherein a reproduction signal level at the mark forming portion is increased, and the shape of the substrate of the optical disc recording medium is increased. The present invention relates to a playback apparatus and a playback method for playing back an optical disk recording medium configured so that a playback signal level at a mark formation portion is lowered in an optical disk recording medium that is physically transferred.
Further, the sub-recording medium is formed on a substrate and an optical disk recording medium formed by laminating at least a reflective film and a cover layer on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate. The present invention relates to a recording apparatus and method for recording data, an optical disc manufacturing method for manufacturing the optical disc recording medium, and an optical disc recording medium.

  As an optical disk, in particular, a read-only ROM disk is widely used around the world as a package medium because a large number of replica substrates can be manufactured in a short time by plastic injection molding from a single stamper. For example, CDs (Compact Discs), DVDs (Digital Versatile Discs), and the like are widely used as ROM disks for recording information such as music and video.

Conventionally, so-called pirated discs have been created by illegally copying the recorded data based on ROM discs sold as package media in this way, and copyright infringement has been a problem.
In general, a pirated disc is produced by producing a stamper by producing a stamper by a mastering process based on a signal reproduced from a regular disc. Alternatively, it is created by copying a signal reproduced from a regular disc to a recordable disc.

  Various techniques have been proposed to prevent the production of pirated discs. One of them is a technology for adding different identification information for each disc, for example. In this way, by adding different identification information to each disk, it is possible to construct a system in which the playback device reads the identification information and transmits it to an external server device via a network. If such a system is used, for example, when a pirated disk is created and sold, a large amount of the same identification information is detected by the server device, so that the presence of the pirated disk can be detected. Furthermore, it may be possible to specify a pirated dealer by specifying the playback apparatus that has transmitted the detected identification information.

However, it is useful for copyright protection that identification information unique to each disc is recorded so that it cannot be easily copied by a commercially available drive device.
Therefore, for example, in Patent Document 1 below, the identification information is recorded by forming a mark on the reflective film of the disk to give a slight change in reflectance. That is, in the disc described in Patent Document 1, main data (content data, management information, etc.) is recorded by a combination of pits and lands, and a minute reflection with respect to a reflective film on a predetermined pit or land. By forming a mark that gives a rate change, sub data (identification information) other than the main data is recorded.

The mark recording on the reflective film is performed by laser irradiation with a recording power higher than the laser power during reproduction. At this time, the change in reflectance due to the mark is made minute so as not to affect the reproduction of the main data recorded by the combination of pits and lands. That is, this prevents the sub data from being reproduced in the normal reproduction operation for the main data.
For the reproduction of the sub data itself, a separate reproduction system is provided, and a large number of such subtle reflectance change portions in the reproduction signal of the main data are sampled to obtain these integral values, for example. It can be carried out.
In this case, the position where the mark as the sub data is to be formed is determined by the predetermined algorithm on the sub data recording apparatus side and the reproducing apparatus side. Thereby, since the position where a mark should be recorded can be specified by the same algorithm as that used at the time of recording in a regular reproducing apparatus, identification information as sub data can be reproduced appropriately.

Japanese Patent No. 3454410

By the way, the pirated disc is assumed to be created from the reproduction signal of the regular ROM disc. However, as another method, a stamper is created by transferring the physical shape of the substrate of the ROM disc as it is. Conceivable.
Specifically, the shape of the pits and lands formed on the substrate is exposed by peeling the disc cover layer and the reflective film from the substrate. Then, by physically transferring the concavo-convex shape thus exposed, the content recorded on the disk is duplicated.

  In the disc described in Patent Document 1, identification information for each disc is recorded by a mark formed on the reflective film. According to this, the physical transfer method that requires the cover layer and the reflective film to be peeled off from the substrate as described above cannot transfer even the mark (identification information) formed on the reflective film. Therefore, it is considered that the production of pirated discs can be prevented.

However, the recording of the mark on the reflective film as described above is performed by irradiation with a relatively high output laser. Such high-power laser irradiation may cause, for example, thermal expansion or the like due to an increase in the medium temperature at a mark recording portion, which may deform the substrate.
In other words, there is a possibility that a mark that should be formed only on the reflective film is physically transferred to the substrate, and further, this substrate is physically transferred so that the main data and the sub data are duplicated. There is a possibility of being.

This will be described with reference to FIG.
First, FIG. 23A shows a cross-sectional structure of the disk 100 in which marks are formed on the reflective film as described above.
As shown in the figure, the disk 100 includes at least a substrate 101, a reflective film 102, and a cover layer 103. The cross-sectional shape of the unevenness formed between the substrate 101 and the reflective film 102 is a portion where main data is recorded by a combination of pits and lands.
As described above, a mark as sub-data is recorded on the reflection film on a predetermined pit or land (X in the figure). In the example shown in the figure, an example is shown in which marks are recorded on a reflective film on a predetermined land.

As described above, at the time of recording a mark as sub-data, the reflective film 102 is irradiated with a relatively high-power laser, so that the mark formation portion X is deformed due to thermal expansion accompanying the temperature rise. May occur.
Along with this deformation, a concave recess is transferred to the surface of the substrate 101 that contacts the reflective film 102. That is, in this case, when the cover layer 103 and the reflective film 102 are peeled and the substrate 101 is exposed, the surface of the substrate 101 is formed only on the reflective film 102 as shown in FIG. The concave shape corresponding to the power mark is transferred.

The transferred concave portion becomes a portion where the reflectance slightly decreases with respect to other land portions. In other words, a replica substrate created by transferring the concave shape of the substrate 101 as it is is a reproduction of the mark as sub data as it is.
Then, if the reflective film and the cover layer are laminated in the same manner as the normal manufacturing process for such a replica substrate, a pirated disc in which the main data and the sub data recorded on the regular disc are copied exactly is manufactured. Can be made.

Therefore, in the present invention, in view of the above problems, first, the reproducing apparatus is configured as follows.
That is, it is formed by laminating a substrate and at least a reflective film and a cover layer on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate, and laser light by recording power is recorded. An optical disk recording medium in which sub-data is recorded by marks formed on the reflective film by irradiation, the reproduction signal level at the mark forming portion is increased, and the shape of the substrate of the optical disk recording medium is physically changed As a reproducing apparatus for reproducing an optical disk recording medium that is configured so that the reproduction signal level at the mark forming portion is reduced in the optical disk recording medium generated by the automatic transfer, first, with respect to the optical disk recording medium, A reproduction signal generator for detecting the reflected light of the laser beam by the irradiated reproduction power and generating the reproduction signal. Equipped with a.
Further, a sub data detection unit is provided for detecting the value of the sub data based on a result of detecting the value of the reproduction signal generated by the reproduction signal generation unit at a predetermined sampling point.
Further, based on the result of determining whether or not the value of the sub data detected by the sub data detecting means has been obtained with an appropriate polarity, it is determined whether or not the optical disc recording medium is a regular version disc. Judgment means is provided.

In the present invention, the recording apparatus is configured as follows.
That is, the recording apparatus of the present invention is an optical disc on which main data is recorded by a combination of a pit and a land formed on a substrate and at least a reflective film and a cover layer on the substrate. A recording apparatus for recording sub-data by forming a mark on the reflective film by irradiating a laser beam with a recording power on the land having a predetermined length as a target,
A mark in which the reproduction signal level at the mark formation portion increases and the reproduction signal level at the mark formation portion decreases in an optical disk recording medium generated by physically transferring the shape of the substrate of the optical disk recording medium. A recording means is provided for recording the sub data by irradiating the laser beam with the recording power so that the mark is formed according to the size and the mark depth.

First, as a premise, the present invention is formed by laminating a substrate and at least a reflective film and a cover layer on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate. Further, the present invention relates to an optical disk recording medium on which sub data is recorded by marks formed on the reflection film by irradiation of laser light with recording power. As a result of experiments on such an optical disk recording medium, as will be described later, the reproduction signal level at the mark forming portion is increased, and the optical disk recording generated by physically transferring the shape of the substrate of the optical disk recording medium It was confirmed that it was possible to manufacture an optical disc recording medium having such a characteristic that the reproduction signal level at the mark formation portion was lowered. That is, with such an optical disc recording medium, it is possible to reverse the polarities of the sub data obtained for the regular version and the pirated version.
Therefore, the reproducing apparatus of the present invention is configured to determine whether or not the value of the sub data is obtained with the proper polarity as described above. That is, if the polarity is appropriate, it can be determined that the disc is a regular version. If the polarity is not appropriate, it can be determined that the disc is a pirated disc.
Here, the characteristic that the reproduction signal level rises with the regular version disc and the reproduction signal level declines with the pirated version disc as described above is obtained when the mark is recorded on the land side. It has been derived that whether or not the characteristics are obtained is related to the size and depth of the mark to be formed. Therefore, as in the recording apparatus of the present invention, for a land having a predetermined length, a mark in which the reproduction signal level is increased in the mark formation part in the regular version and the reproduction signal level is lowered in the mark formation part in the pirated version. The sub-data is recorded by irradiating the laser beam so that the mark is formed according to the size and the mark depth, so that the polarity of the reproduction signal obtained from the regular version disc and the pirated disc is reversed. An optical disc recording medium can be manufactured.
The “optical disk recording medium produced by physically transferring the shape of the substrate” as used in the present invention means that a reflective film is formed on a replica substrate produced based on a stamper produced by physically transferring the shape of the substrate. It refers to the one produced by film formation. The same applies to a substrate formed by re-depositing a reflective film on a substrate from which the reflective film has been peeled off.

As described above, according to the present invention, it is possible to provide an optical disc recording medium in which the reproduction signal level increases in the mark formation part in the regular version and the reproduction signal level decreases in the mark formation part in the pirated version. Thus, it is possible to provide an optical disk recording medium in which the polarity of the value of the sub data reproduced by the regular version disk and the pirated version disk is reversed.
In particular, according to the reproducing apparatus (reproducing method) of the present invention, it is configured to determine whether or not the value of the sub data detected from such an optical disc recording medium is obtained with an appropriate polarity. Thus, it can be determined whether or not the optical disk recording medium is a regular disk.

Hereinafter, the best mode for carrying out the invention (hereinafter referred to as an embodiment) will be described.
The description will be given in the following order.

<1. Optical disc recording medium>
<2. Sub data recording device>
<3. Playback device>
<4. Optical Disc Recording Medium, Recording Device, and Reproducing Device as Embodiment>

<1. Optical disc recording medium>

First, FIG. 1 shows a cross-sectional structure diagram of a disk 100 as an optical disk recording medium of the embodiment.
The disc 100 according to the embodiment is a read-only ROM disc, and specifically adopts a disc structure and format compliant with a disc called a Blu-ray Disc (Blu-Ray Disc).
The disk 100 includes a substrate 101, a reflective film 102 laminated on the substrate 101, and a cover layer 103 as shown in the figure. The substrate 101 is a plastic substrate made of polycarbonate or the like, for example, and the surface of the substrate 101 that is in contact with the reflective film 102 is provided with an uneven sectional shape. The concave cross section is a pit, and the convex cross section is a land. In the disc 100, information can be recorded by a combination of these pits and lands, specifically, the lengths of the pits and lands.

A reflective film 102 is laminated on the substrate 101 on which the pits and lands are formed. A cover layer 103 made of polycarbonate or the like is further laminated on the reflective film 102.
The reflective film 102 is laminated on the substrate 101 to give a concavo-convex cross-sectional shape corresponding to the shape of the pits and lands as described above. The reflective film 102 is, for example, a metal film, and when the laser light condensed by the objective lens is irradiated through the cover layer 103 as shown in the figure, the reflected light corresponding to the unevenness is obtained. It is supposed to be. On the side of the sub data recording apparatus 50 and the reproducing apparatus 1 described later, information recorded by a combination of pits and lands can be detected based on the reflected light from the reflection film 102 of the irradiated laser light.

FIG. 2 is a diagram for explaining the manufacturing process of the disk 100.
In manufacturing the disk 100, first, the formatting step S11 in the figure is executed. This formatting step S11 is performed using, for example, a computer.
In the formatting step S11, a conversion operation is performed on the content data (user data) to be recorded on the disc 100 so that a format data string according to a predetermined standard is obtained. That is, in the case of the embodiment, the conversion operation is performed so as to obtain a data string according to the Blu-ray disc standard as described later in FIG. In practice, addition of error detection code and error correction code to user data, interleaving processing, and the like are also performed.

In the variable length modulation step S12, variable length modulation processing is performed on the data string generated in the formatting step S11. In the case of the embodiment, RLL (1, 7) PP (Parity preserve / prohibit, RLL: Run Length Limited) modulation processing and NRZI (Non Return to Zero Inverse) modulation processing are performed. The “0” “1” pattern of the data string obtained by the variable length modulation step S12 becomes a pattern of pits and lands actually formed on the disc 100.
Data obtained by formatting user variable data and performing variable-length modulation processing in this way is referred to as main data here.

Subsequently, the master generation step S13 is performed. The master production step S13 is performed using a mastering device.
In the master production step S13, first, a photoresist is applied to the glass master. Then, by irradiating the laser beam according to the main data generated in the variable length modulation step S12 in a state where the glass master coated with the photoresist is rotationally driven in this manner, a pattern of unevenness along the recording track Form. In other words, pits and lands are formed.
Next, the resist on which the pits and lands are formed is developed and fixed on the glass master, and the surface of the master is electroplated to generate the metal master D14 shown in the figure.

The disc forming step S15 is performed using the metal master D14 thus generated.
In the disk forming step S15, a stamper is first created based on the metal master D14. And this stamper is arrange | positioned in a shaping | molding die, and the board | substrate 101 is formed with transparent resins, such as a polycarbonate and an acryl, using an injection molding machine. On this substrate 101, pit and land patterns corresponding to the main data generated in the previous modulation step S12 are formed along the recording track.
A reflective film 102 is first laminated on the substrate 101 by vapor deposition or the like, and a cover layer 103 is further laminated on the reflective film 102. As a result, a disk (main data recording disk) D16 on which only main data is recorded is formed.

Subsequently, the sub data recording step S17 is executed.
Here, in the embodiment, sub data is recorded in addition to the main data recorded by the pit and land pattern as described above.
In this case, the sub-data records serial number information that is unique to each disk 100 (disk D16) as actual data that is the data content portion. In other words, as a result of each of the discs 100 generated in the sub data recording step S17, unique identification information (identification number) is added to the disc 100.
Further, in addition to the identification information as the actual data, in this case, an error correction code is also added as the sub data. By attaching this error correction code, it becomes possible to perform an error correction process on the identification information during reproduction.

The sub-data is recorded by forming a mark by laser irradiation with recording power on the reflective film 102 at a specific position in a specific section of the main data by pits and lands as described later. It will be.
Such a sub data recording step S17 is performed by a sub data recording apparatus 50 described later with reference to FIG.

  In this case, only the identification information and the error correction code are included as the sub data, but other data can be added.

FIG. 3 shows the data structure of main data recorded on the disc 100 manufactured by the above manufacturing process.
First, as shown in the drawing, one recording unit called RUB is defined. One RUB is composed of 16 address units (“sector” in the figure) and two linking frames. The linking frame is provided as a buffer area between the RUBs.
One address unit in this case forms one address unit.
Each address unit is composed of 31 frames as shown in the figure. One frame is composed of 1932 channel bits of data.
In the Blu-ray disc exemplified in the embodiment, the main data is in accordance with the RLL (1, 7) PP modulation rule, and the continuous number of codes “0” and “1” (that is, the pit length and the land) The length) is limited to a length of 2T (channel bits) to 8T.
In the sync positioned at the head of each frame, a 9T continuous code that does not follow this modulation rule is inserted and used to detect a frame synchronization signal during reproduction.

<2. Sub data recording device>

Next, FIG. 4 shows a configuration of the sub data recording device 50 for recording the above sub data on the disk D16.
As described above, as sub data, identification information unique to each disk 100 is recorded as the data content. Accordingly, the operation of the sub data recording device 50 is to record sub data with a different pattern for each disc 100 to be loaded.
Further, the sub data has a predetermined section for recording the sub data on the disk D16, and is further predetermined as a position for inserting each mark in the section. The sub data recording device 50 is configured to record a mark at such a predetermined specific position.

First, the disk D16 is rotationally driven by the spindle motor 51 in accordance with a predetermined rotational driving method while being placed on a turntable (not shown). The optical pickup OP shown in the figure reads the recording signal (main data) from the disk D16 that is driven to rotate in this way.
This optical pickup OP is based on a laser diode LD as a laser light source as shown, an objective lens 52 for condensing and irradiating a laser beam onto the recording surface of the disk 100, and the laser light irradiation from the disk D16. A photodetector PD for detecting reflected light is provided.

  Reflected light information detected by the photodetector PD in the optical pickup OP is converted into an electric signal by the IV conversion circuit 53 and then supplied to the matrix circuit 54. The matrix circuit 54 generates a reproduction signal RF, a tracking error signal TE, and a focus error signal FE based on the reflected light information from the IV conversion circuit 53.

The servo circuit 55 controls the tracking drive signal TD and the focus drive signal FD output from the biaxial drive circuit 56 based on the tracking error signal TE and the focus error signal FE from the matrix circuit 54. These tracking drive signal TD and focus drive signal FD are supplied to a biaxial mechanism (not shown) that holds the objective lens 52 in the optical pickup OP, and based on these signals, the objective lens 52 moves in the tracking direction, It is driven in the focus direction.
In the tracking servo / focus servo system using the servo circuit 55, the 2-axis drive circuit 56, and the 2-axis mechanism, the servo circuit 55 performs control based on the tracking error signal TE and the focus error signal FE, thereby irradiating the disk D16. Control is performed so that the beam spot of the laser beam traces the pit row (recording track) formed on the disk D16 and is maintained in an appropriate focus state.

  The reproduction signal RF generated by the matrix circuit 54 is supplied to a binarization circuit 57 where it is converted into binarized data of “0” and “1”. The binarized data is supplied to a synchronization detection circuit 58 and a PLL (Phase Locked Loop) circuit 59.

  The PLL circuit 59 generates a clock CLK synchronized with the supplied binarized data, and supplies this as an operation clock for each necessary unit. In particular, the clock CLK is also supplied as an operation clock for the binarization circuit 57 and a synchronization detection circuit 58, an address detection circuit 60, and a sub data generation circuit 61 which will be described below.

The synchronization detection circuit 58 detects the sync pattern inserted for each frame shown in FIG. 3 from the supplied binary data. More specifically, the frame synchronization detection is performed by detecting the 9T section that is the sync pattern in this case.
The frame synchronization signal is supplied to necessary units such as the address detection circuit 60.

  The address detection circuit 60 detects address information based on the frame synchronization signal and the supplied binary data. The detected address information is supplied to a controller (not shown) that performs overall control of the sub data recording device 50 and used for a seek operation or the like. This address information is also supplied to the recording pulse generation circuit 63 in the sub data generation circuit 61.

The sub data generation circuit 61 includes a recording pulse generation circuit 63 and a RAM (Randam Access Memory) 62 as shown in the figure. This sub data generation circuit 61 is based on the sub data to be input, the address information supplied from the address detection circuit 60 and the clock CLK supplied from the PLL circuit 59, and the sub data to be recorded on the disk D16. A recording pulse signal Wrp for recording data in the form described later with reference to FIG. 5 is generated.
The operation of the sub data generation circuit 61 will be described later.

The laser power control unit 64 controls the laser power of the laser diode LD in the optical pickup OP based on the recording pulse signal Wrp output from the sub data generation circuit 61. Specifically, the laser power control unit 64 in this case performs control so that the laser output by the reproduction power is obtained when the recording pulse signal Wrp is at the L level. Further, when the recording pulse signal Wrp is at the H level, control is performed so that the recording power is obtained.
When laser irradiation is performed with recording power under the control of the laser power control unit 64, a mark is formed on the reflective film 102 in the laser irradiation portion. Thus, the sub data is recorded on the disk D16 by the mark formed on the reflective film 102.

FIG. 5 is a diagram for explaining a recording mode of sub data to be realized by the operation of the sub data generating circuit 61 described above.
FIG. 5 shows an example in which “0” is recorded as a 1-bit code constituting sub data and “1” is recorded.
First, as a method for expressing a code, an odd number (odd) and an even number (even) adjacent to each other for a predetermined length of land existing in the main data are considered as one set. For each of the odd-numbered and even-numbered pairs adjacent to these predetermined length lands, the code is “0” when the odd-numbered mark is recorded, and “1” when the even-numbered mark is recorded. Define.
The example of FIG. 5 shows an example in which marks are recorded on a land of 5T as a predetermined length land.

In this case, one address unit, which is one address unit, is assigned as a section to be assigned to recording of 1-bit code constituting the sub data.
That is, as shown in this figure, marks are recorded in a form expressing the same code for each pair of adjacent odd-numbered and even-numbered predetermined-length lands in one address unit.
Specifically, when the code “0” is recorded, as shown in the figure, marks are recorded only on odd-numbered lands of a predetermined length in one address unit.
When the code “1” is recorded, the mark is recorded only for the even-numbered land of the predetermined length in one address unit.

Although details will be described later, at the time of reproduction, the reproduction signal RF is sampled for every adjacent odd-numbered and even-numbered pairs of predetermined length lands in one address unit, and the value of the reproduction signal RF sampled at the odd-numbered unit is used. The value of the reproduction signal RF sampled at the even number is subtracted (“odd-even”).
Here, in the same way as in the prior art, considering the example in which the reproduction signal level of the recorded mark is lower than the reproduction signal level in the unrecorded portion, the code “0” in which the mark is recorded only in odd numbers When such an “odd-even” operation is performed, a negative value is ideally obtained for each adjacent predetermined length land. That is, by integrating the value of “odd-even” calculated for each adjacent predetermined length land in this way, a negative value can be obtained reliably and detected.
On the contrary, in the case of the code “1” in which the mark is recorded only in the even number, the value of “odd-even” calculated for each adjacent predetermined length land is ideally a positive value. Therefore, by integrating this, a positive value can be reliably obtained and detected.

In the disc 100 according to the present embodiment, the reproduction signal level at the mark forming portion is increased as will be described later, so that only the odd-numbered recording is actually performed. In this case, a positive value is detected, and a negative value is detected when mark recording is performed only in the even number.
Here, for convenience of explanation, recording is performed by the sub-data recording apparatus 50 by the same method as the conventional one, and the following explanation is continued on the assumption that the reproduction signal level decreases in the mark recording portion.

  Here, as described above, the same recording pattern is repeatedly recorded over a specific section, and at the time of reproduction, one value is determined based on the plurality of the same recording patterns. The change in reflectance is very small and can be a foot. As described above, since the reflectance change accompanying the mark recording can be made minute, the recorded mark can be prevented from affecting the binarization processing of the main data.

For other codes constituting the sub data, marks are recorded by the same method as described above.
That is, in this case, the sub data is recorded over the same number of address units as the codes constituting the sub data.
The section for recording the sub data in this way (hereinafter also referred to as a sub data recording target section) is determined in advance between the sub data recording apparatus 50 and the reproducing apparatus. Therefore, the sub data recording apparatus 50 is configured to execute the above-described mark recording over a plurality of address units as sub data recording target sections determined in advance.

Here, in the above recording method, it should be noted that when the mark to be recorded on the predetermined land is recorded on the edge portion, the binarization of the main data is not properly performed. This means that there is a positive possibility. That is, when a mark is recorded on the edge portion of a land having a predetermined length in this way, the reflectance tends to decrease correspondingly in the mark recording portion, so that an incorrect land length (or pit length) is obtained in the binarization process. May be detected.
Therefore, the mark is recorded in the center of the land to be recorded. According to this, since the edge portion can be obtained as usual, this point is also made so as not to affect the binarization processing.

  The recording pulse generation circuit 63 in the sub data generation circuit 61 shown in FIG. 4 generates the recording pulse signal Wrp at the timing as shown in FIG. . That is, in response to the code “0”, the recording pulse signal Wrp that is at the H level only in the center portion of the odd-numbered predetermined length land is generated. In correspondence with the code “1”, the recording pulse signal Wrp which becomes the H level only in the central portion of the even-numbered predetermined length land is generated.

The configuration and operation for realizing the recording technique described above will be described with reference to FIGS.
First, as described above, the recording of the sub data is performed in a predetermined sub data recording target section on the disc D16. Then, in the sub-data recording target section determined in this way, as described above, when recording marks only on the odd-numbered or even-numbered lands in each address unit, such sub-data recording is performed. It is necessary to grasp the contents of the main data in each address unit in the target section.
Therefore, in the sub data generation circuit 61 shown in FIG. 4, the contents of the main data for each address unit in the recording target section are stored in the RAM 62 in advance.

FIG. 6 shows a data structure in the RAM 62.
First, the illustrated address indicates address information of each address unit in the sub data recording target section. For each address, the contents of main data recorded in each address unit are stored.
For confirmation, the sub data recording device 50 is a device managed by the manufacturer of the disk D16 (disk 100). Therefore, the contents of main data recorded on the disk D16, which is a ROM disk, can be grasped in advance. For this reason, the contents of the main data actually recorded on the disk D16 can be stored in advance in the RAM 62 in correspondence with addresses as described above.

  Further, in the RAM 62, the value of the sub data to be recorded at the address is stored corresponding to the address. Each value of the sub data is stored in the RAM 62 by the recording pulse generation circuit 63. The recording pulse generation circuit 63 stores each value of the sub data supplied from the outside in the RAM 62 in order from the head address in the sub data recording target section.

In this way, the recording pulse generation circuit 63 can specify a land portion of a predetermined length in the main data and further specify the odd number and even number thereof according to the data content stored in the RAM 62.
At the same time, by referring to the value of the sub-data stored in correspondence with the address as described above, it is possible to specify the odd-numbered and even-numbered land of the specified predetermined length land to be inserted.
Specifically, when the value stored in association with the address is “0”, as shown in FIG. 5, the odd-numbered predetermined-length land in the address unit of the address. In this case, a mark should be inserted, and if it is “1”, it can be recognized as an even-numbered one.
Further, in this case, the mark should be inserted into the central portion of the recording target land as described above. Therefore, after specifying the recording target land as described above, the recording pulse signal Wrp which becomes the H level at the timing when the mark is recorded in the central portion of the land is generated.

As a specific example of generation of such a recording pulse signal Wrp, first, ALL0 data based on the number of channel bits for one address unit is prepared. Then, a data string in which the code “1” is inserted at the timing specified as described above may be generated for the ALL0 data. That is, as a data string for one address unit, a data string in which only a bit position where a mark is to be inserted is set to “1” and all other bits are set to “0” is generated.
Based on such a data string, the recording pulse generation circuit 63 supplies the recording pulse signal Wrp which becomes H level only at the timing of the appropriate mark recording position as shown in FIG. can do.

Next, the sub data recording operation performed by the sub data recording device 50 will be described in more detail with reference to the flowchart of FIG.
First, in step S101, the disk D16 is loaded. In step S102, sub data is input. The sub data input to the sub data recording device 50 is supplied to the sub data generation circuit 61 as shown in FIG.
As described above, the sub data input here is data including identification information and an error correction code unique to each disk D16 (disk 100).
Here, sub data is input after the disc 100 is loaded, but these may be mixed.

In step S103, each value of the sub data is stored for each address.
That is, in the operation of step S103, each value of the sub data inputted by the recording pulse generation circuit 63 in the sub data generation circuit 61 is stored for each address in the RAM 62 having the structure shown in FIG. Corresponds to the action.

In step S104, the address value N is set to the initial value N0.
Step S104 is an operation for setting the value of the internal counter to the initial value N0 when the recording pulse generation circuit 63 performs an operation of generating a data string for each address as described below.

  In step S105, an operation for determining the value of the sub data to be recorded at the N address is performed. That is, as the operation of step S105, the recording pulse generation circuit 63 sets “0” as the value associated with the corresponding address based on the counter value among the sub-data values stored in the RAM 62 corresponding to the addresses. Determine “1”.

When it is determined that the value of the sub data is “1”, the recording pulse generation circuit 63 inserts “1” at the position of the even-numbered central portion of the predetermined length land in the main data in the N address. The generated data string is generated (step S106).
In other words, as a result, the data string by the number of channel bits for one address unit is “1” only at the timing of the center of the even-numbered predetermined length land as described above, and all other codes are “0”. A data string is generated.
On the other hand, when it is determined that the value of the sub data is “0”, the recording pulse generation circuit 63 sets “1” at the position of the odd-numbered central portion of the predetermined length land in the main data in the N address. Is generated (step S107). In other words, as a result, the data string by the number of channel bits for one address unit becomes “1” only at the timing of the center of the odd-numbered predetermined length land as described above, and all other codes are “0”. A data string is generated.
As can be understood from the above description, such a data string is generated by the recording pulse generation circuit 63 based on the contents of the main data stored in the RAM 62 corresponding to each address. This can be done by specifying a long land and a bit position that is the center of the land.

When the data string for one address unit is generated in this way, the recording pulse generation circuit 63 determines whether or not the address is completed (S108). That is, it is determined whether or not the generation of the data string has been completed for all the address units in the sub data recording target section. The operation in step S108 is performed by determining whether or not the value of the counter that has been set to the initial value N0 in the previous step S104 by the recording pulse generation circuit 63 has reached a predetermined value.
If a negative result is obtained because the counter value has not reached the predetermined value, the address value N is incremented by 1 (step S109), and then the process returns to the previous step S105. As a result, the operation for generating the data string is performed for all address units in the sub-data recording target section.

If it is determined in step S108 that the counter value has reached the predetermined value and the address ends, sub-data recording starts in step S110.
In response to the start of recording of the sub data, first, an operation of seeking to the head address of the sub data recording target section on the disc 100 is performed (step S111). The seek operation in step S111 can be performed by, for example, a controller that performs overall control of the sub data recording device 50 controlling each necessary unit based on predetermined address information of the sub data recording target section.

Then, in response to the seek operation to the head address of the sub-data recording target section as described above, the sub-data generation circuit 63 generates the data string generated for each address unit by the operations of the previous steps S106 and S107. Is generated and output to the laser power controller 64 (step S112). The recording pulse signal Wrp based on this data string is generated based on the timing of the clock CLK so as to be synchronized with the main data to be reproduced.
The output of the recording pulse signal Wrp is triggered by the fact that the address information supplied from the address detection circuit 14 is supplied with the information on the start address of the recording target section.

  As described above, as the recording pulse signal Wrp generated based on the data string by the recording pulse generation circuit 63, a signal that becomes H level at an appropriate timing as shown in FIG. 5 is obtained. Accordingly, the laser power control unit 64 controls the laser output of the laser diode LD from the reproduction power to the recording power based on the recording pulse signal Wrp, so that the disc D16 corresponds to the value of the input sub data. Marks can be recorded at appropriate positions.

  Although the sub data is input from the outside, a circuit is provided for generating a new serial number every time the disk D16 is loaded, and the sub data based on the identification information input from this circuit is stored in the RAM 62. It can also be.

Although the description is omitted, the contents of the main data to be recorded are the same. For the disc D16 having the same title, the main data stored in the RAM 62 can be recorded with the same contents and the sub data can be recorded. However, when the sub data is recorded on the disc D16 having a different title, the content of the main data stored in the RAM 62 may be updated in accordance with the content of the main data recorded on the disc D16.

<3. Playback device>

Next, with respect to the configuration of the reproducing apparatus 1 that reproduces the disc 100 on which the sub data is recorded by the marks formed on the reflective film 102 as described above, the following block diagram of FIG. The description will be given with reference.
In FIG. 8, only the part related to the reproduction of sub data is mainly extracted and shown, and the configuration of the demodulation system in the latter stage of the binarization process is omitted as the configuration of the reproduction system of the main data.
In the following description, it is assumed that there are no inversion circuit 15 and determination circuit 16 surrounded by a broken line in the figure.

In the reproducing apparatus 1, the disk 100 is rotationally driven by the spindle motor 2 in accordance with a predetermined rotational driving method while being placed on a turntable (not shown). Also in this case, the optical pickup OP shown in the figure reads the recording signal (main data) from the disk 100 that is driven to rotate.
Although not shown in the figure, also in the optical pickup OP in this case, a laser diode serving as a laser light source, an objective lens for condensing and irradiating the laser light onto the recording surface of the disk 100, and the objective lens in the tracking direction and focus There are provided a biaxial mechanism for displacing in the direction, a photodetector for detecting reflected light based on the laser light irradiation from the disk 100, and the like.
For confirmation, the laser light applied to the disk 100 in the reproducing apparatus 1 is based on the reproducing power.

The reflected light information detected by the photodetector in the optical pickup OP is converted into an electrical signal by the IV conversion circuit 3 and then supplied to the matrix circuit 4. The matrix circuit 4 generates a reproduction signal RF based on the reflected light information from the IV conversion circuit 3.
Although not shown, the signals generated by the matrix circuit 4 include a tracking error signal TE and a focus error signal FE. These are supplied to a servo circuit (not shown) and used for tracking servo and focus servo control operations, respectively.

The reproduction signal RF generated by the matrix circuit 4 is supplied to the binarization circuit 5 and branched and supplied to an A / D converter 11 described later.
The binarization circuit 5 converts the supplied reproduction signal RF into binarized data “0” and “1”. Then, the binarized data is supplied to the PLL circuit 8, the synchronization detection circuit 9, and the address detection circuit 10.
The binarized data is also supplied to a detection pulse generation circuit 12a in the detection pulse generation unit 12 described later.

The PLL circuit 8 generates a clock CLK synchronized with the supplied binarized data, and supplies this as an operation clock for each necessary unit. In particular, the clock CLK in this case is also supplied to the detection pulse generation circuit 12a (not shown).
The synchronization detection circuit 9 detects the sync portion inserted for each frame shown in FIG. 3 from the supplied binary data. More specifically, the frame synchronization detection is performed by detecting the 9T section that is the sync pattern in this case.
The frame synchronization signal is supplied to each necessary unit including the address detection circuit 10.

  The address detection circuit 10 detects address information from the supplied binary data based on the frame synchronization signal. The detected address information is supplied to a controller (not shown) that performs overall control of the playback apparatus 1 and used for a seek operation or the like. The address information is also supplied to the detection pulse generation circuit 12a in the detection pulse generation unit 12.

  For confirmation, the optical pickup OP, the IV conversion circuit 3, the matrix circuit 4, the binarization circuit 5, the PLL circuit 8, the synchronization detection circuit 9, and the address detection circuit 10 described so far are as follows. This portion is also used when reproducing main data recorded on the disc 100. In other words, these units share the structure of the main data reproduction system when reproducing the sub data.

The detection pulse generator 12 detects a detection point corresponding to a mark recording method determined in common with the previous sub data recording device 50 when reproducing the identification information as sub data. A signal Dp is generated.
In the detection pulse generation unit 12, a detection pulse generation circuit 12a and a RAM 12b are provided. The detection pulse generation circuit 12a generates the detection pulse Dp based on the information stored in the RAM 12b. Then, the generated detection pulse signal Dp is supplied to the A / D converter 11.

A reproduction signal RF from the matrix circuit 4 is supplied to the A / D converter 11. The A / D converter 11 samples the supplied reproduction signal RF at a timing indicated by the detection pulse signal Dp and supplies the value to the sub data detection circuit 13.
The sub data detection circuit 13 performs a predetermined calculation on the value supplied from the A / D converter 11 to detect each value of the sub data. In other words, for example, in this case, each value of the sub data is detected based on the result of the calculation corresponding to “odd-even” described above.
The sub-data value detection operation performed by the detection pulse generator 12, the A / D converter 11, and the sub-data detection circuit 13 will be described later.

The value of the sub data detected by the sub data detection circuit 13 is supplied to an ECC (Error Correcting Code) circuit 14. Note that, as described above, in this description, it is assumed that there are no inversion circuit 15 and determination circuit 16 in the broken line.
In this case, the sub data includes identification information and an error correction code. The ECC circuit 14 reproduces the identification information by performing error correction processing based on the error correction code in the sub data.

The reproduced identification information is supplied to the host computer 6 shown.
The host computer 6 sends commands to a controller (not shown) that performs overall control of the playback apparatus 1 to instruct various operations. For example, a command for instructing reproduction of main data recorded on the disc 100 is transmitted. In response to this, the main data reproduced from the disc 100 is binarized by the binarization circuit 5 and then demodulated (RLL1-7PP demodulation), error correction processing, etc. by a demodulation system not shown. It is supplied to the host computer 6.
The host computer 6 is provided with a network interface 7 for performing data communication via a required network. As a result, the host computer 6 can perform data communication with an external device, particularly, the management server 70 shown in the figure via a predetermined network such as the Internet.
The operation of this embodiment by the host computer 6 and the management server 70 will be described later.

The sub data value detection operation performed in the playback apparatus 50 having the above configuration will be described with reference to FIG.
FIG. 9 shows a mark recording state when “0” is assigned to each address unit on the disk 100 as a 1-bit value of sub data and when “1” is assigned. Yes. For the sake of illustration, this figure shows a case where pits and lands as main data are formed in the same pattern.

First, as described above, the sub data is recorded so that 1-bit information is allocated to each address unit in a predetermined sub data recording target section on the disc 100.
In this case, as a method for expressing a code, “0” is defined when a mark is recorded on an odd-numbered land of a predetermined length, and “1” is defined when a mark is recorded on an even-numbered land. That is, as shown in the figure, when the code is “0”, the mark is recorded only in the odd-numbered lands of a predetermined length in the address unit. When the code is “1”, marks are recorded only in even-numbered lands of a predetermined length in the address unit.

Here, in the description so far, the portion where the mark is recorded is treated as a portion where the reflectance slightly decreases. According to this, the level of the waveform of the reproduction signal RF slightly decreases in the portion where the mark is recorded as shown in the figure.
In the reproduction of the sub data, an operation for determining each value based on such a slight change in reflectance at the mark recording portion is performed.

  As described above, each mark is recorded on the center portion of the predetermined land when the sub data is recorded. Since the mark is recorded at the center of the land in this way, as can be understood with reference to the waveform of the reproduction signal RF shown in this figure, the level of the land where the mark is recorded decreases only at the center. Thus, the waveform of the edge portion is obtained as usual. As a result, the binarization of the main data can be prevented from being affected as described above.

Here, according to the above description, when the code is “0”, the value of the reproduction signal RF slightly decreases only in the odd-numbered predetermined length land. When the code is “1”, the value of the reproduction signal RF slightly decreases only in the even-numbered predetermined length land.
Therefore, in this case, in determining each value of the sub-data assigned to each address unit, the value of the reproduction signal RF decreases in either the odd-numbered or even-numbered direction for the predetermined length land in the address unit. What is necessary is just to detect whether it is.

A decrease in the value of the reproduction signal RF in the mark recording portion can be detected by, for example, obtaining a difference from the value of the reproduction signal RF in the mark unrecorded portion.
At this time, as described above, when the code is “0”, only the odd number is recorded, and when the code is “1”, the mark is recorded only in the even number. In other words, when the code is “0” It can be seen that the even number is always an unrecorded portion, and when it is “1”, the odd number is always an unrecorded portion.
From this, the odd-numbered (odd) and even-numbered (even) adjacent to each other are subjected to the calculation based on “odd-even”, and the value of the reproduction signal RF is reduced by either “odd” or “even”. Can be checked).
Specifically, if “odd-even” is a negative value, it is found that the value of the reproduction signal RF at the odd number is lowered, and therefore the mark is recorded at the odd number. On the contrary, if “odd-even” is a positive value, the even-numbered value is decreased, and it can be seen that the even-numbered mark is recorded.

However, in practice, a noise component is superimposed on the reproduction signal RF. As described above, the decrease in the value of the reproduction signal RF in the mark recording portion is very small, and there is a possibility of being buried in such a noise component. Therefore, it is difficult to reliably determine the value if the detection by the “odd-even” is performed only for even-numbered pairs of adjacent lands having a predetermined length.
For this reason, as a sub-data reproduction operation, the “odd-even” value calculated for each odd-numbered and even-numbered pair adjacent to each other as described above is integrated and assigned to the address unit based on this integrated value. The 1-bit value thus determined is determined. By doing in this way, the value of subdata can be detected more reliably.

  By the way, in order to calculate “odd-even” as described above, it is necessary to sample the value of the reproduction signal RF obtained at the central portion of odd and even, that is, both odd-numbered and even-numbered predetermined length lands. is there. As a signal for instructing the sampling timing for calculating the “odd-even”, the detection pulse generator 12 shown in FIG. 8 generates a detection pulse signal Dp in the drawing.

Here, as described above with reference to FIG. 9, the detection pulse signal Dp for calculating “odd-even” as described above is an H level only at the center of a predetermined length land obtained in the main data. It is sufficient to generate the following signal.
In the generation of such a detection pulse signal Dp, the main data recorded in the sub data recording target section on the disc 100 is generated in the same manner as the generation of the recording pulse signal Wrp in the case of the previous sub data recording device 50. The corresponding timing may be generated from the contents of.

  However, since the reproducing apparatus 1 is not used on the disc manufacturing side as in the case of the sub data recording apparatus 50, the contents recorded on the disk 100 cannot be stored in the apparatus in advance. . Therefore, the reproducing apparatus 1 reads the main data of the sub-data recording target section from the loaded disc 100, stores it in the apparatus, and uses it to generate the detection pulse signal Dp.

As a memory for storing the main data of the sub-data recording target section read out in this way, the reproducing apparatus 1 is provided with the RAM 12b in the detection pulse generation unit 12 shown in FIG. As shown in FIG. 10, the data structure stores main data read corresponding to each address.
In the detection pulse generation circuit 12a in the detection pulse generation unit 12, the same applies as in the case of the previous generation of the recording pulse signal Wrp based on the contents of the main data in the recording target section stored in the RAM 12b. A data string is generated that becomes “1” only at the timing and becomes “0” for all others. Then, a detection pulse signal Dp based on the data string generated in this way is generated and supplied to the A / D converter 11. The A / D converter 11 samples the value of the reproduction signal RF at the timing indicated by the detection pulse signal Dp, thereby sampling the value of the reproduction signal RF at an appropriate timing as shown in FIG. Can do.

Next, a more detailed operation at the time of sub data reproduction performed in the reproducing apparatus 1 will be described with reference to the flowchart of FIG.
First, when the disc 100 is loaded in step S201, in step S202, the operation of storing main data for each address is performed for the sub data recording target section on the disc 100.
Here, when the disc 100 is loaded, for example, in response to an instruction from the host computer 6 shown in FIG. 8, a seek is made to the head address of the sub-data recording target section determined in advance with the sub-data recording apparatus 50. Then, an operation of reading main data recorded in the recording target section is executed. For the main data read out in this way, the detection pulse generation circuit 12a shown in FIG. 8 converts the binarized data supplied from the binarization circuit 5 to each address based on the address information supplied from the address detection circuit 10. And stored in the RAM 12b.

In step S203, the address value N is set to the initial value N0.
In step S203, when the detection pulse generation circuit 12a performs an operation of generating a data string indicating the sampling timing of the reproduction signal RF for each address unit as described below, the value of the internal counter is set to the initial value. This is an operation to set to N0.

In step S204, a data string in which “1” is inserted at the central position of the predetermined length land in the main data in the N address is generated.
The operation in step S204 is performed with reference to the content of main data stored in the RAM 12b by the detection pulse generation circuit 12a. In other words, the detection pulse generation circuit 12a has only “1” for the position of the central portion of the predetermined length land in the main data stored in the RAM 12b in association with the N address, and “0” for all the others. To generate a data string. For example, in this case, since a mark is recorded on a 5T land, only the third bit position in this 5T section is “1”, and all other data strings are “0”. Should be generated.
By such an operation, a data string indicating a sampling point in the address unit of N addresses is generated.

When the data string indicating the sampling points for one address unit is generated in this way, the detection pulse generation circuit 12a determines whether or not the address has ended (S205). That is, it is determined whether or not the generation of the data string has been completed for all the address units in the sub data recording target section. The operation in step S205 is performed by the detection pulse generation circuit 12a determining whether or not the counter value set as the initial value N0 in the previous step S203 has reached a predetermined value set in advance.
If a negative result is obtained that the counter value has not reached the predetermined value, the address value N is incremented by 1 (step S206), and then the process returns to step S204. As a result, the operation for generating the data string is performed for all address units in the sub-data recording target section.

If it is determined in step S207 that the counter value has reached the predetermined value and the address has ended, reproduction of sub data is started in step S208.
In response to the start of reproduction of the sub data, an operation of seeking to the head address of the sub data recording target section on the disc 100 is performed (step S209). The seek operation in step S209 is realized, for example, when the host computer 6 shown in FIG. 8 gives an instruction to the controller (not shown) described above based on the address information of the sub-data recording target section determined in advance. Is done.

Then, in response to the seek operation to the head address of the sub-data recording target section as described above, the detection pulse generation circuit 12a is based on the data string generated for each address unit by the operation of the previous step S204. A detection pulse signal Dp is generated and output to the A / D converter 11 (step S209). The generation of the detection pulse signal Dp based on the generated data string is performed based on the timing of the clock CLK so as to be synchronized with the main data to be reproduced.
The output of the detection pulse signal Dp is triggered by the fact that the information of the start address of the recording target section is supplied as the address information supplied from the address detection circuit 14.

In the subsequent step S210, an operation of detecting the value of the sub data by a calculation based on “odd-even” for the value sampled based on the detection pulse signal Dp is performed.
The operation in step S210 is performed by the A / D converter 11 and the sub data detection circuit 13.
That is, the A / D converter 11 samples the value of the reproduction signal RF supplied from the matrix circuit 4 at a timing indicated by the detection pulse signal Dp supplied from the detection pulse generation circuit 12a. Then, the value is output to the sub data detection circuit 13.
The sub-data detection circuit 13 subtracts the even-numbered value from the odd-numbered value for the value supplied from the A / D converter 11 so that “odd-even” described in FIG. Perform the operation. Then, the value of “odd-even” calculated in this way is integrated for each address unit, and the value of the sub data is detected based on the integrated value.

Each value of the sub data detected in this way is supplied to the ECC circuit 14, and error correction processing based on the error correction code in the sub data is performed to reproduce the identification information. The reproduced identification information is supplied to the host computer 6 and used as copyright management information.
The operation using the identification information supplied to the host computer 6 as this embodiment will be described later.

<4. Optical Disc Recording Medium, Recording Device, and Reproducing Device as Embodiment>

As described above, the sub-data can be recorded and reproduced by the marks formed on the reflective film 102 of the disk 100.
Here, as described above, the marks formed on the reflective film 102 are recorded so as not to affect the reproduction of the main data recorded by the combination of pits and lands. The sub data is not reproduced only by doing. Accordingly, there is an advantage that the sub data recorded by such a mark on the reflective film 102 is not copied to a pirated disk that copies the reproduction signal of the disk 100.

However, such a mark is recorded by irradiating the reflective film 102 with a relatively high output laser beam. In such a portion irradiated with high-power laser, the medium temperature rises, and in some cases, there is a possibility that the substrate 101 located under the reflective film 102 is deformed due to thermal expansion or the like.
This state is shown in FIG. 23A. In the mark recording portion indicated by X in the drawing, when the temperature rises, for example, when thermal expansion or the like occurs, a concave depression is generated in the substrate 101. Become.

Here, when the substrate 101 is exposed by peeling the cover layer 103 and the reflective film 102 from such a disc 100, the mark recording portion as sub-data is formed on the surface thereof as shown in FIG. The corresponding depression is left.
In the concave portion left in accordance with the mark recording portion, the reflectance slightly decreases due to diffraction. That is, when such a shape of the substrate 101 is physically transferred, it becomes possible to manufacture a pirated disk in which the sub data is reproduced as it is. As a pirated disk by physical transfer, mass production becomes possible by creating a stamper on the basis of the substrate 101 having a concave recess and creating a replica substrate on the basis of this stamper.

Therefore, as one method for dealing with such a pirated disk by physical transfer, the polarity of the value of the detected sub data is reversed between the regular disk 100 and the pirated disk by physical transfer. Can be considered.
In other words, by utilizing such a difference in polarity and determining whether or not the value of the secondary data can be obtained with the assumed polarity, it is possible to determine whether the disc is a regular version disc or a pirated disc. To do.

For this purpose, it is conceivable to obtain the characteristic that the reproduction signal level at the mark forming portion is increased as the regular version of the disc 100. Has succeeded in developing the disc 100 in which the reproduction signal level increases.
The characteristics are shown in FIG.

In FIG. 12, Amplitude on the vertical axis indicates a value obtained by integrating the value obtained by subtracting the unrecorded portion from the recorded portion of the mark as the value of the reproduction signal RF. That is, the larger the value, the higher the value of the reproduction signal RF in the mark recording portion. Pw (mW) on the horizontal axis indicates the laser power during recording.
In this figure, the characteristic indicated by the solid line indicates the characteristic of the regular version disc 100 on which the mark recording is performed by the sub data recording device 50, and the characteristic indicated by the broken line indicates a pirated disc in which physical transfer is performed on the regular version disc 100. The characteristics of are shown.

The recording conditions set for obtaining the experimental results shown in FIG. 12 will be described.
First, mark recording was performed on a 5T land as a land having a predetermined length of the disk 100. Further, as the material of the reflective film 102 of the disk 100, an AgSn alloy was adopted and a film thickness of 40 nm was formed.
The conditions set in the sub data recording device 50 for manufacturing the disc 100 are as follows.
Numerical aperture NA = 0.85, laser wavelength λ = 405 nm, recording linear velocity = 4.9 m / s, mark recording pulse = 30 ns
Further, the structure of the disk 100 (main data recording disk D16) conforms to the Blu-ray disk exemplified in the embodiment, the track pitch Tp is 320 nm, the length of 1T is 78 nm, and the pit width is Tp / 3. The pit depth is λ / 5.
The pirated disc used in the experiment was molded based on a stamper obtained by separating the reflective film 102 from the disc 100 on which mark recording was performed under the above conditions, extracting the substrate 101, and physically transferring from the substrate 101. The substrate 101 is formed by forming a reflective film 102.

First, it can be seen that in the disc 100 as the regular version in which the present experiment indicated by the solid line is performed, the value of Amplitude on the vertical axis increases at a value larger than 0 level in the range of laser power of 12 mW to 25 mW. That is, it can be understood from these characteristics that the reproduction signal level in the mark recording portion is increased.
On the other hand, in the pirated disk indicated by the broken line, it can be seen that the Amplitude value decreases at a value smaller than 0 level with respect to the same change in laser power, and the reproduction signal level decreases.
From this, it can be seen that the polarity of the reproduction signal RF at the mark recording portion is different from that of the pirated disc physically transferred from the disc 100 as the present embodiment. That is, the polarity of the reproduction signal RF can be made different in the mark recording portion between the regular version disc 100 and the pirated disc created based on this.

  As a result of the experiment, when mark recording was performed for the pit portion, the reproduction signal level only decreased with increasing laser power. That is, when mark recording is performed for the pit portion, the polarity of the reproduction signal RF is not reversed between the regular version and the pirated version.

For reference, FIG. 13 shows the shape of the substrate 101 when mark recording is performed on the disc 100 under the setting of the conditions of the sub data recording apparatus 50 described in FIG. ) Shows a schematic diagram of the results observed.
FIG. 13A shows the observation result of the plane of the substrate 101, and FIG. 13B shows the result of observing the cross-sectional shape of the substrate 101 at the cut surface indicated by the solid line X in FIG. . Moreover, broken lines a to e shown in FIG. 13B indicate positions of the broken lines a to e shown in FIG.
As can be seen with reference to these drawings, it can be confirmed that the depth of the mark recording portion M is deeper than the depth (for example, cd) of the normal land portion. Also from this, it can be understood that the substrate 101 is deformed by the concave shape along with the mark recording. Further, the mark width of the mark recording portion M can be viewed as the width of the portion whose depth is deeper than the normal land portion in FIG. 13B. In this case, the mark width is a broken line as shown in the figure. It can be confirmed that the width is slightly wider than the width of one track indicated by a to b.

  Here, in the disc 100 of the present embodiment, the reproduction signal level of the mark recording portion increases as in the previous experimental results of FIG. 12, and in the pirated disc based on this disc 100, the reproduction signal level of the mark recording portion is The decreasing principle will be described with reference to FIGS.

First, referring to FIG. 14, the characteristics of the reproduction signal level at the mark recording portion when the mark recording is performed on the land having a predetermined length on the disc on which the main data is recorded by the combination of the pit and the land are calculated by simulation. The results are shown.
In FIG. 14, the value of the reproduction signal RF in the unrecorded portion of the mark is calculated from the value of the reproduction signal RF in the mark recording portion when the mark depth is on the vertical axis and the mark reflectance is on the horizontal axis. It shows the change characteristics of the subtracted difference signal (same as Amplitude shown in FIG. 12).
The optical conditions set for obtaining the calculation result of FIG. 14 will be described with reference to FIG. 15. First, the track pitch Tp is 320 nm, the pit width is Tp / 3 (320/3 nm), and the pit depth is λ. / 5. Further, the mark M is assumed to be a square with a mark width Mw = mark length Ml as shown in the figure, and is formed on a land portion of 6T. In this case, the length of 1T is 78 nm, and the length of 6T is 468 nm. Although not shown, the laser wavelength λ in this case is 405 nm and the numerical aperture NA is 0.85.
The mark amplitude reflectance Rm was Rm = Am exp (4 × pi × i × N × d), and Rim-intensity was 100%. Further, the calculation unit cell is 22T × 3 tracks.
As can be seen from comparison with the optical conditions described with reference to FIG. 12, the conditions of the laser wavelength λ, numerical aperture NA, track pitch Tp, pit width, and pit depth in this case are as follows. It was set to be equivalent to (D16).

14 (a), (b), and (c), the mark width Mw is Mw = 0.5 Tp, Mw = 1.0 Tp, and Mw = 1.5 Tp, respectively, under the optical conditions described above. It shows the characteristics of the differential signal when In this case, according to the description of FIG. 15, since the mark width Mw = the mark length Ml, these figures show the differential signal characteristics when the size of the mark M is changed.
14A to 14C, first, if the mark M is not formed, the mark depth is “0” and the mark reflectance is “1”. Thus, at the intersection of the mark depth “0” where the mark M is not formed and the mark reflectance “1”, the value of the difference signal based on “recorded portion−unrecorded portion” is “0” as shown in each figure. "

Here, as a factor that increases the reproduction signal level, it is considered that the reflectance at the mark recording portion increases. Alternatively, the reproduction signal level may increase without increasing the mark reflectivity.
As a result of conducting a mark recording experiment on the reflective film 102 having various compositions in International Publication No. WO01 / 008145, the present applicant previously found that the reflectance increased in the mark recording portion and the reflectance in the mark recording portion. I have confirmed that there are cases where I do not.
As an example, the composition of the reflective film 102 in which the reflectance increases at the mark recording portion includes Ag _95.5 Cr _4.5 (subscript indicates the ratio of each element), and the composition in which the mark reflectance does not increase. _Includes Ag _95.0 Si _{5.0 and the} like.

  Here, first, consider the case where the reproduction signal level rises without increasing the reflectance in the latter mark recording portion.

When attention is paid to FIG. 14 on the premise that the reflectance does not increase in the mark recording portion in this way, in each case, the mark depth indicated by the colored portion in the drawing reaches a certain mark depth starting from the mark depth “0”. It can be seen that a portion where the reproduction signal level increases without increasing the mark reflectivity is obtained.
In this case, however, it can be seen that when the mark width Mw = 0.5 Tp, as shown in the figure, the mark reflectivity does not increase and a portion where the reproduction signal level increases is hardly obtained. On the other hand, as the mark width Mw is expanded to 1.0 Tp and 1.5 Tp, it can be seen that the portion where the reproduction signal level increases without increasing the mark reflectivity tends to be expanded.
According to such characteristics, in this case, if the mark width Mw (that is, the mark size) is too small, a portion where the reproduction signal level rises without increasing the mark reflectivity cannot be obtained. It can be seen that the playback signal level may not be raised.
Therefore, it can be seen that the size of the mark is one element in order to increase the reproduction signal level in the mark recording portion.

  In particular, as can be seen with reference to FIG. 14B, when the mark depth exceeds a certain range, the reproduction signal level changes to a negative value, and the reproduction signal level decreases at the mark recording portion. I understand that. According to this, it can be understood that even the mark depth is an element that increases the reproduction signal level.

As another simulation result, FIG. 16 shows the difference signal characteristics when the mark depth is changed under the same optical condition setting as described in FIG. (B) Similar to (c), mark widths Mw = 0.5 Tp, 1.0 Tp, and 1.5 Tp are shown. The difference signal in FIG. 16 indicates the difference from the reproduction signal level when the mark depth d = 0, and indicates the reproduction signal level itself obtained when the mark depth is used.
According to this simulation result, when Mw = 0.5 Tp shown in FIG. 16A, the difference signal slightly rises from 0 level and the reproduction signal level rises slightly when the mark depth is 2 nm. Recognize. As the mark depth is further increased, the difference signal turns to a negative value, and the reproduction signal level decreases.
Further, when the mark width Mw = Tp, the difference signal becomes larger than 0 level when the mark depth is expanded to 2 nm and 4 nm, and when it is further deepened, the reproduction signal level is lowered.
It can also be seen that when the mark width Mw = 1.5 Tp, the level of the differential signal increases as the mark depth increases, and the reproduction signal level tends to increase as the mark depth increases.

  Therefore, it can be understood from the simulation result that the mark width Mw (mark size) and the mark depth are the determining factors as to whether or not the reproduction signal level in the mark recording portion is increased.

Since these figures are simulation results only, the mark width Mw is fixed and only the mark depth is changed. However, in practice, the laser power is increased to increase the mark depth. If so, the mark width Mw is also enlarged accordingly.
Therefore, in actual recording, both the mark depth and the mark width Mw are enlarged as the laser power increases.
In consideration of this, the characteristic of FIG. 14 is that the difference signal as shown in the transition of FIG. 14 (a) → (b) → (c) is actually obtained by expanding the mark depth. It can be understood that the change in characteristics occurs simultaneously.

  Here, as can be understood from the above simulation results, under the assumption that the reflectance does not increase at the mark recording part, the playback signal level at the mark recording part is increased by setting the mark depth and mark width. However, if the factors that increase the playback signal level in the mark recording part are the mark depth and the mark width, as described above, the pirated disc that has been physically transferred as described above is used as it is. If the dent of the substrate 101 is reproduced, the same mark depth and mark width conditions are satisfied even in the pirated disc, and as a result, the reproduction signal level at the mark recording portion may be similarly increased. it can.

However, as shown in the previous FIG. 12, it has been confirmed that the pirated disc that has undergone physical transfer has a characteristic that the reproduction signal level is lowered as the disc 100 of the embodiment.
In this way, in the pirated disc, the reproduction signal level at the mark recording portion is lowered due to the following principle.

Here, in FIG. 14 and FIG. 16, it is assumed that a groove as the mark M is formed on the substrate 101 itself, but actually, the reflective film 102 is laminated on the substrate 101.
When the reflective film 102 is irradiated with laser light with recording power, the reflective surface that is the target of the reproducing optical system is not actually the surface of the reflective film 102, for example, in the following FIG. It is known that it is between the substrate 101 and the reflectance 102 as indicated by the broken line. Here, the reflection surface that is the target of the reproducing optical system is called an optical reflection surface, and the depth is called an optical depth.

When the mark is recorded, the optical depth of the regular version disc 100 is as shown in FIG. That is, in the regular version, due to a change in the optical constant such as oxidation of the reflective film 102 accompanying the mark formation, the optical depth is not the same as the depth faithful to the concave depression given to the substrate 101, but a shallower position. Become.
On the other hand, in the case of a pirated disk, the reflective film 102 with the changed optical constant is once peeled off, and then the reflective film 102 is formed again on the substrate 101 (replica substrate) obtained by physical transfer. As shown in FIG. 17 (c), the optical depth is faithful to the hollow shape of the substrate 101, so that the position is deeper than the optical depth of the regular version.

In this way, the optical depth of the pirated disc becomes deeper, so that the polarity of the reproduction signal level is reversed between the regular version disc and the pirated disc.
This will be described with reference to FIG. FIG. 18 shows the differential signal characteristics similar to those of FIG. 14B (when the mark width Mw = Tp).
In this figure, if the depth of the mark recorded on the regular version disc is pSK in the figure, if the pirated disc has a greater optical depth as described above, The mark depth on the pirated disc can be, for example, a position shown as pKZ in the figure.
In other words, since the optical depth of the pirated disc is made deeper in this way, the value of the difference signal on the regular version disc is on the positive polarity side. As shown in the figure, the difference signal = “0” is exceeded and the signal is turned to the negative polarity side, so that the polarity of the reproduction signal is reversed between the pirated disk and the regular disk.

Here, according to such a principle, even if the optical depth of the pirated disc becomes deeper, for example, if the mark depth recorded on the disc 100 is not sufficient, the reproduction signal level is a negative value. It turns out that there is a possibility of not turning to.
For example, in FIG. 18, if the mark depth of the mark recorded on the disk 100 is considerably shallower than the position of pSK in the figure, the position of pKZ in the figure is located outside the line of differential signal = 0. It is not unthinkable that the reproduction signal level becomes a positive value similar to that of the regular disc.
Therefore, according to this, it can be said that the mark depth in this case is also an element that determines whether or not the reproduction signal level is lowered in the pirated disc.

In this way, the reproduction signal level at the mark recording portion increases in the disc 100 (regular edition disc) on which mark recording is actually performed, and the reproduction signal level at the mark recording portion decreases in the pirated disc. It can be seen that the size and depth of the marks recorded on the disc 100 are the determining factors.
For this reason, with respect to the disc 100 (main data recording disc D16), the reproduction signal level at the mark recording portion of the regular version disc increases in this way, and the reproduction signal level at the mark recording portion of the pirated disc has such an increase. By recording (forming) the mark with the reduced mark size and mark depth, the polarity of the reproduction signal RF obtained in the mark recording portion can be reversed between the regular disc 100 and the pirated disc. .
The optical conditions set for the disc 100 and the sub data recording device 50 described above are such that the reproduction signal level of the mark recording portion increases in the regular version, and the reproduction signal level in the mark recording portion decreases in the pirated version. The mark size and the mark depth are satisfied.
This makes it possible to reverse the polarity of the reproduction signal level obtained at the mark recording portion between the regular version disc 100 and the pirated disc as shown in the experimental results shown in FIG. Then, from the difference in the polarity of the reproduction signal RF between the regular version and the pirated version, it is possible to determine the regular version disk and the pirated version disk.

Here, description has been made on the premise that the reproduction signal level is increased without increasing the reflectance in the mark recording portion. However, as described above, the reflectance in the mark recording portion is increased. As a result, the playback signal level may increase.
As described above, even when the reproduction signal level rises due to an increase in the mark reflectivity, the reproduction signal level in the mark recording part increases in the regular version disk as described above, and in the mark recording part in the pirated disk. By recording (forming) the mark with the mark size and mark depth at which the reproduction signal level decreases, the polarity of the reproduction signal RF obtained in the mark recording portion is reversed between the regular disc 100 and the pirated disc. can do.

FIG. 19 shows the simulation result of the differential signal characteristic (when the mark width Mw = Tp) as in FIG. 18, but the level of the reproduction signal RF is also increased by increasing the mark reflectivity as described above. In the case of rising, the mark depth and the reflectance of the mark recorded on the regular version disk are values indicated by, for example, pSK in the figure. That is, the point pSK in this case indicates that the substrate 101 is deformed by the formation of the mark to give a certain mark depth, and the reflectance increases at the mark recording portion and the reproduction signal RF increases. ing.
Then, considering the case where a pirated disc is generated based on a regular disc on which marks having the mark depth and mark reflectivity specified by the point pSK are recorded, the mark depth is first described. According to the description of FIG. 17, the pirated disc has an optical depth that is faithful to the hollow shape of the substrate 101, so that even in this case, the pirated version is more optical than the regular version. The depth is deeper.
As for the reflectance, since the reflective film 102 is newly formed in the pirated edition, the reflectance at the mark portion returns to “1”.
From these facts, the mark depth and mark reflectivity of the pirated disk manufactured from the regular disk in this case can be values as indicated by pKZ in FIG. 19, for example. In other words, like this change from pSK to pKZ, the value of the difference signal exceeds “0” and turns to the negative polarity side, and even in this case, reproduction is performed on the pirated disc and the regular disc. The polarity of the signal RF is reversed.

Then, the transition of the mark unrecorded → the mark recorded → the pirated disc in FIG. 19 and the transition of the difference signal characteristic according to the mark size shown in FIGS. 14 (a) → (b) → (c) As described above, even in this case, depending on the depth and size of the mark formed on the regular disc, the optical depth is increased in the pirated disc as described above, and the reflectance of the mark portion is increased. Even if becomes “1”, it can be understood that there is a possibility that the difference signal = “0” is not exceeded and the negative signal side is not turned.
That is, even in this case, the depth and size of the mark formed on the regular version disc may be a factor that determines whether or not the polarity of the reproduction signal RF is reversed between the pirated version disc and the regular version disc. Understandable.

  For this reason, even in the case where the mark reflectivity is increased and the reproduction signal level is increased in the regular version disc, the disk 100 is also similar to the case where the reproduction signal level is increased without increasing the previous reflectivity. With respect to (main data recording disk D16), the mark size and mark depth at which the reproduction signal level at the mark recording portion increases in the regular version disk and the reproduction signal level at the mark recording portion decreases in the pirated disk as described above. Thus, by recording (forming) the mark, it is possible to reverse the polarity of the reproduction signal RF obtained in the mark recording portion between the regular disc 100 and the pirated disc.

  For confirmation, in the present embodiment, the reproduction signal level of the mark recording portion rises in the regular version, and in the pirated version, according to the optical conditions set for the disc 100 and the sub data recording device 50 described above. Experimental results have been obtained with the polarity reversed. Therefore, even under the assumption that the mark reflectivity is increased in the mark recording portion and the reproduction signal level is increased in this way, the optical condition set in the present embodiment is that the reproduction signal level of the mark recording portion is the regular version. In the pirated version, the mark size and the mark depth that satisfy the condition that the reproduction signal level at the mark recording portion is lowered and the mark signal depth is obtained are satisfied.

In the above, assuming that the reflectance is increased and the playback signal level is increased, the pirated disc is marked as a regular version and a pirated version by adding a deeper optical depth than the regular version disc. Although the description has been made on the assumption that the polarity of the reproduction signal RF of the part is reversed, it is not considered that the optical depth is equal between the regular version and the pirated version. Even in such a case, it is not considered that the polarity of the reproduction signal RF is reversed between the pirated version and the regular version.
As shown in FIG. 20, the polarity of the reproduction signal RF of the mark portion is reversed between the pirated version and the regular version even when the optical depth is the same between the pirated version and the regular version. Can be considered.
Note that FIG. 20 also shows the simulation result of the differential signal characteristic when the mark width Mw = Tp, as in FIGS.

In FIG. 20, in this case as well, mark depth and reflectivity increase to some extent with mark recording, and the mark depth and mark reflectivity of the mark formed on the regular version disk are, for example, pSK in the figure. A value as shown can be obtained.
In this case, since it is assumed that the optical depth of the regular version disc is equal to that of the pirated edition disc, there is no difference in mark depth between the regular version and the pirated edition. It will only change to. That is, in the example of this figure, the mark depth and mark reflectivity on the pirated disc change only to the mark reflectivity to “1”, as compared to the above-described pSK that represents the mark depth and mark reflectivity of the regular disc. Thus, the position becomes pKZ in the figure, and the signal goes to the negative polarity side beyond the line of differential signal = “0”.

However, in FIG. 20, when the mark is not recorded → when the mark is recorded → the transition of the pirated disc and the transition of the differential signal characteristic corresponding to the mark size shown in FIGS. 14 (a) → (b) → (c). As can be seen, even in this case, when the depth and size of the mark formed on the regular version disc is not appropriate, the mark reflectivity is changed to “1” as a pirated disc as described above. However, it can be understood that the polarity of the reproduction signal RF may not change to the negative polarity on the pirated disc side. For example, in FIG. 20, when the mark depth is about 4 nm or less, the polarity remains positive even on the pirated disc side and does not reverse.
Therefore, when the mark reflectivity increases and the playback signal level rises, even if it is assumed that the optical depth does not change between the regular version disc and the pirated disc, it is formed on the regular version disc. It can be seen that the depth and size of the marks to be determined are factors that determine whether the polarity of the reproduction signal is reversed between the pirated disc and the regular disc.
In other words, even in this case, with respect to the disc 100 (main data recording disc D16), the reproduction signal level of the mark recording portion increases in the regular version disc and the reproduction signal level of the mark recording portion decreases in the pirated disc. By recording (forming) the mark according to the mark size and mark depth to be performed, the polarity of the reproduction signal RF obtained in the mark recording portion can be reversed between the regular disc 100 and the pirated disc. There will be no change.

  Each condition set as the sub data recording device 50 (numerical aperture NA = 0.85, laser wavelength λ = 405 nm, recording linear velocity = 4.9 m / s, mark recording pulse = 30 ns, laser power = 12 mW to 25 mW) Is an example only, and as can be understood from the above description, in this case, the mark that increases the reproduction signal level at the mark recording portion on the regular version disc and decreases the reproduction signal level at the mark recording portion on the pirated disc. By setting the conditions for performing mark recording according to the depth and the mark size, the disc 100 in which the polarity of the reproduction signal is reversed between the regular version disc and the pirated disc can be similarly generated.

The conditions set as the disk 100 (main data recording disk D16) are the same as those described above (track pitch Tp = 320 nm, pit width = Tp / 3, pit depth = λ / 5, 1T length = 78 nm). ), And other conditions may be adopted.
Further, mark recording can be performed on a land having a length other than 5T (and 6T).
However, if the condition on the disc 100 (D16) and the length of the land on which the mark is recorded change in this way, the relative relationship between the size and depth of the recorded mark also changes. The same differential signal characteristic as the characteristic cannot be obtained.
However, the difference signal characteristics similar to that of FIG. 14 can be obtained under the condition that the mark recording is performed on the disc on which the main data is recorded by the same combination of pits and lands (particularly, the reflectance increases). If it is assumed that the reproduction signal level rises without the difference, the difference signal that can obtain the portion where the reproduction signal level rises without increasing the mark reflectivity as shown by the colored portion in FIG. In this case, the secondary data recording device 50 performs mark recording on the regular version disc according to the difference signal characteristic which is different from the case of FIG. Mark recording is performed with the mark size and mark depth at which the reproduction signal level at the portion increases and the reproduction signal level at the mark recording portion decreases in the pirated disc. By conditions that can bets is set, it is possible to produce a disk 100 in which the polarity of the reproduced signal is inverted in the same manner as in regular version disk and pirated disk.

  In addition, as described above, the manufacturing method of the disc 100 shown in FIG. 2 is that the reproduction signal level in the mark recording portion increases in the regular version disc and the reproduction signal level in the mark recording portion decreases in the pirated disc as described above. The sub-data recording step S17 is performed using the sub-data recording apparatus 50 in which conditions for performing mark recording according to the mark depth and the mark size to be performed are performed, so that a reproduction signal is generated between the regular version disc and the pirated disc. Can be produced.

  Here, for confirmation, the reproduction signal waveform of the disc 100 of this example in which the reproduction signal level rises at the mark recording portion as described above will be described with reference to FIG. In FIG. 21, as in the case of FIG. 9, “0” is assigned to each address unit on the disk 100 as a 1-bit value of sub data, and “1” is assigned. The mark recording state at.

As shown in this figure, in the disc 100 of this example, the level of the reproduction signal RF slightly increases in the portion where the mark is recorded. That is, as the sub data in this case, when the code is “0”, the value of the reproduction signal RF slightly increases only in the odd-numbered (odd) predetermined length land. On the other hand, when the code is “1”, the value of the reproduction signal RF slightly increases only in the even-numbered (even) predetermined land.
That is, in this case, as the calculation result by “odd-even”, a positive value is obtained corresponding to the sign “0”, and a negative value is obtained corresponding to the sign “1”. .

  Note that, depending on the conventional configuration of the playback apparatus 1 described with reference to FIG. 8, the sign “0” is detected in response to the value of “odd-even” being “negative”. "1" is detected in response to "." In this sense, when mark recording is performed such that the reproduction signal level rises at the mark recording portion as in this example, a code opposite to the conventional one is recorded.

By the way, if the characteristic that the reproduction signal level in the mark recording portion increases in the regular version disc and the reproduction signal level in the mark recording portion decreases in the pirated disc as described above is used, it is loaded on the reproducing apparatus side. It is possible to determine whether the disc is a regular disc 100 or a pirated disc.
Hereinafter, the configuration of the reproducing apparatus 1 according to the present embodiment, which makes it possible to determine a pirated disk using the characteristics of the disk 100 according to the present embodiment, will be described.

In the reproducing apparatus 1 according to the present embodiment, an inverting circuit 15 and a determination circuit 16 shown in a broken line in FIG. 8 are added to the configuration described in FIG.
In this case, the value of the sub data detected by the sub data detection circuit 13 is supplied to the inverting circuit 15. The inversion circuit 15 inverts the polarity of the supplied sub data value and supplies it to the ECC circuit 14.

Here, when the disc 100 according to the present embodiment is reproduced by the reproducing apparatus 1, the sub data value detected by the sub data detecting circuit 13 is the reverse of the conventional value as described above. It will be. That is, the sub-data detection circuit 13 detects the sign “0” in response to the “odd-even” operation result being “negative” and the sign “1” in response to being “positive”, as in the conventional case. This is due to the fact that “is detected”. In this sense, the sub data value detected by the sub data detection circuit 13 in this case is obtained by inverting the sub data value recorded on the sub data recording device 50 side.
Therefore, the value of the sub data that is the same as that recorded is obtained by inverting the value by the inverting circuit 15 as described above. That is, according to the reproducing apparatus 1 provided with the inverting circuit 15 as described above, the same sub data value as that at the time of recording can be detected from the disc 100 of the present embodiment that has been normally manufactured.

Conversely, when sub data is reproduced from a pirated disc manufactured by physical transfer, the sub data value detected by the sub data detection circuit 13 is non-inverted, and the sub data value obtained via the inversion circuit 15 is non-inverted. Is a reverse pattern of the recorded one.
That is, it is possible to prevent the correct sub data value from being obtained from the pirated disk.

Here, since the value of the sub data is obtained from the regular version disk 100 with the correct polarity as described above, the ECC circuit 14 can normally perform error correction processing on the identification information in the sub data. . That is, the contents of the sub data can be correctly reproduced.
On the other hand, the value of the secondary data from the pirated disc with the wrong polarity is also the reverse polarity as the error correction code, so the error correction processing cannot be performed normally, and the content (identification information) of the secondary data is correct. Cannot play.
From this, it is possible to determine from the result of the error correction process in the ECC circuit 14 whether or not the appropriate polarity is obtained as the value of the sub data, and from the determination result of the polarity, the regular version of the disc 100 is obtained. Or a pirated disc.

  As a configuration for performing such determination, the playback device 1 includes a determination circuit 16. The determination circuit 16 is connected to the ECC circuit 14 as shown in the figure, so that it can be determined whether or not the error correction processing has been normally performed in the ECC circuit 14. Based on the determination result as to whether or not the error correction processing has been normally performed as described above, it is possible to determine the regular version disk 100 and the pirated version disk as described above.

  Furthermore, in this embodiment, when a pirated disc is determined from the determination result of the determination circuit 16, the identification information reproduced from this disc is transferred to the host computer 6. As will be described later, this identification information is sent to the management server 70 by the host computer 6 via the network interface 7 and is notified as an identification number of a disk distributed as a pirated disk. .

However, the fact that a pirated disc has been determined is a case where the ECC circuit 14 has not successfully obtained identification information. That is, identification information for notifying as a pirated disk cannot be obtained as described above.
Therefore, the determination circuit 16 converts the value of the sub data detected by the sub data detection circuit 13 into the correct polarity in response to the determination of the pirated disk, and then converts it to the ECC circuit 14 again. An error correction process is performed to reproduce the identification information.

Here, the operation as the present embodiment performed by the determination circuit 16 in this way will be described with reference to the flowchart of FIG.
First, the determination circuit 16 determines whether or not there is an error in the error correction processing in the ECC circuit 14 (step S301). That is, it is determined whether or not an appropriate polarity is obtained as the value of the sub data detected by the sub data detection circuit 13, and based on the result of the determination, whether the disc 100 is a regular version. It is determined whether the disc is a pirated disc.

If a negative result is obtained that there is no error, first, for example, a code “1” is generated as a legal bit as the operation of step S302 shown in the figure.
This legal bit is information indicating that the disc 100 is a regular version.
In the subsequent step S303, an operation of transferring the legal bits generated in this way and the identification information obtained by the error correction processing of the ECC circuit 14 to the host computer 6 is performed.
In other words, the legal bit “1” indicating the regular version and the identification information are transferred to the host computer 6 as the regular version of the disc 100 is determined by such an operation.

If a positive result is obtained in step S302 that there is an error, an inverting circuit control operation is performed in step S304. This inversion circuit control operation is an operation for converting the value of the sub data into the correct polarity as described above.
That is, the determination circuit 16 supplies the sub data value supplied to the ECC circuit 14 to the inversion circuit 15 and instructs to invert it. For confirmation, the polarity of the sub data detected by the sub data detection circuit 13 for the pirated disc in the reproducing apparatus 1 of the present embodiment is non-inverted, and this is inverted by the inversion circuit 15. By doing so, the polarity is not appropriate. Accordingly, the value of the sub-data having an error as described above can be converted to an appropriate polarity by being inverted again by the inverting circuit 15.

The value of the sub data that has been input to the inverting circuit 15 and whose polarity has been inverted is supplied to the ECC circuit 14 and the error correction process is performed again (step S305). The determination circuit 16 determines again whether or not there is an error in the error correction processing performed in step S305 (step S306).
In the determination operation of step S306, if a positive result is obtained again that there is an error, error processing is performed as shown in the figure. If an error occurs again in this way, there is a possibility that the sub data recorded on the disc itself is incorrect or that the detection operation in the sub data detection circuit 13 has not been performed properly due to some factor. high. Therefore, for example, as the error processing, for example, the determination circuit 16 transfers information indicating that to the host computer 6, and the host computer 6 performs control so as to retry the sub-data detection operation in response thereto. Should be executed.

If a negative result is obtained in step S306 that there is no error, for example, a code “0” is generated as an illegal bit (step S307). In other words, after the above-described inversion circuit control operation (S304) and re-ECC processing (S305), if there is no error in step S306, the sub-data is from a pirated disk with only the polarity reversed. I understand that. In step S306, illegal bits indicating a pirated disc are generated.
Then, in the subsequent step S308, an operation of transferring the illegal bits generated in this way and the identification information obtained by the error correction process again in the ECC circuit 14 to the host computer 6 is performed.
In response to the determination of the pirated disk, the illegal bit indicating the pirated disk and the identification information from the disk are transferred to the host computer 6.

Returning to FIG.
The host computer 6 transmits the legal bit or illegal bit transferred from the determination circuit 6 in this way and the identification information to the external management server 70 via the network interface 7 shown in the figure.
The management server 70 is a device to be managed by a vendor who manages copyright on main data (content data) recorded on the disc 100, such as a vendor of the disc 100. In the management server 70, it is possible to recognize that the disc loaded in the playback device 1 is a regular disc by transmitting a legal bit from the playback device 1 side.
On the other hand, when an illegal bit is transmitted from the playback device 1, the presence of the pirated disc can be recognized, and the identification information is recorded by referring to the identification information transmitted together with the illegal bit. It is also possible to recognize that pirated discs are distributed for the disc 100 that has been recorded.

Here, on the playback device 1 side, the identification information played back from the disc 100 is only notified to the external device, but the host computer 6 is loaded according to the illegal bit transferred from the determination circuit 16. It is also possible to perform control for giving a warning that the disc cannot be reproduced, for example, by controlling the ejection of the disc and displaying a message on a display (not shown).
In this way, the main data recorded on the pirated disc can be prevented from being reproduced.

As described above, according to the reproducing apparatus 1 of the present embodiment, it is possible to correctly reproduce the value of the sub data corresponding to the disc 100 due to the property that the reproduction signal level at the mark recording portion increases.
In other words, in this case, by providing the inversion circuit 15 corresponding to the value of the sub data that is inverted from the conventional one detected from the regular disk 100, the identification information as the sub data is correctly obtained from the regular disk. The ID information cannot be reproduced from the pirated disc.

  Further, in the reproducing apparatus 1 of the present embodiment, whether or not the error correction processing of the sub data has been normally performed in the ECC circuit 14 in response to the case where the sub data includes the error correction code for the identification information. Thus, it is possible to determine whether the disc is a regular version disc or a pirated disc.

  Further, in the present embodiment, in response to the determination of the pirated disk by the determination circuit 16, the identification information and illegal bit are transmitted to the management server 70, so that the presence of the pirated disk is determined. The identification information of the disk 100 that is the basis for manufacturing the pirated disk can be notified to the outside.

The present invention should not be limited to the embodiments described so far. For example, in the embodiment, for ease of explanation, the mark as sub-data is a code “0” depending on which mark is inserted, with odd-numbered and even-numbered adjacent lands having a predetermined length as one set. Although “1” is expressed, in practice, in order to make it difficult for a third party to specify such a recording pattern, the mark insertion position is based on another algorithm such as using an M-sequence random number. Can also be determined.
Even in this case, as long as the rules for the code representation method and the section allocated to one bit of the sub data are defined so as to be common to the sub data recording apparatus 50 and the reproducing apparatus 1 side. Sub-data can be properly reproduced in the reproducing apparatus 1.

In addition, the playback apparatus according to the present embodiment is configured to determine whether or not the value of the detected sub data is obtained with the appropriate polarity depending on whether or not the error correction processing is properly performed. .
However, there are various other configurations for determining whether or not the value of the sub data detected in this way is obtained with an appropriate polarity.
For example, a polarity determination bit is inserted at a predetermined bit position of predetermined sub data. In the case of the regular version, the bit at the predetermined position is obtained with an appropriate value (polarity). Since the pirated version has the opposite polarity, the reproducing apparatus 1 can also determine the pirated disk by determining the value of the inserted bit.

Further, in this embodiment, since the sub data detection circuit 13 similar to the conventional one is provided in the reproducing apparatus 1, the value of the sub data recorded on the regular version disc 100 becomes a reverse pattern from the conventional one. Corresponding to this, an inverting circuit 15 is provided so that proper polarity can be obtained from the regular version. According to such a configuration, there is an advantage that the conventionally used sub data detection circuit 13 can be used without change.
However, in this case, in order to obtain an appropriate polarity from the regular version, it is also possible to record the value of the sub data with the polarity inverted in advance on the disc 100. In such a case, in the reproducing apparatus 1, the proper polarity (that is, the same polarity as that recorded) is obtained from the regular version disc 100 at the time of detection by the sub data detection circuit 13, so that the sub data detection circuit There is no need to provide an inversion circuit 15 that always inverts the polarity of the sub-data value detected at 13.
However, as can be seen with reference to the flowchart of FIG. 22, when the identification information of the pirated disk is notified to the outside, the secondary data from the pirated disk with the wrong polarity is inverted again to correct the error. Need to be processed. Therefore, it is necessary to provide an inverting circuit for this purpose.

Further, if a change is made to the sub data detection circuit 13 that has been conventionally used, it is conceivable to reverse the sub data detection method. That is, as the first technique, contrary to the example illustrated in the embodiment, the sign “0” is detected according to the “positive” value of “odd-even”, and the “negative” value is set. Accordingly, the code “1” is detected.
Also, as a second method, the configuration is such that “even-odd” is calculated in reverse, so that the polarities of the respective difference values are reversed, so that an appropriate sub-data value is detected. It is to make.
Even in this case, since the appropriate polarity is obtained from the regular version disk 100 at the time of detection by the sub data detection circuit 13, the value of the sub data detected by the sub data detection circuit 13 is obtained. It is not necessary to provide the inversion circuit 15 that always performs the polarity inversion.

  Further, as the present embodiment, as the disk 100 in which the reproduction signal level in the mark recording portion increases, for example, a ROM disk compliant with the Blu-ray disk is taken as an example, but as the reproduction apparatus and the reproduction method of the present invention, “The main data is recorded by the combination of pits and lands formed on the substrate and at least a reflective film and a cover layer on the substrate, and the laser beam is irradiated by the recording power. The sub-data is recorded by the mark formed on the reflection film by the above-mentioned optical disc recording medium ”, the reproduction signal level at the mark forming portion is increased, and the shape of the substrate of the optical disc recording medium is physically changed. So that the reproduction signal level at the mark forming portion is lowered in the optical disk recording medium produced by the automatic transfer The made optical disk recording medium, but can be widely applied.

  In the embodiment, the polarity is determined based on the subtraction result between the mark recorded portion (formed portion) and the mark unrecorded portion (unformed portion) as in “odd-even”. It is also possible to fix the reproduction signal level of the portion where the mark is not formed to a certain value, and to determine the polarity based on the subtraction result between the reproduction signal level in the mark recording portion and this fixed value. Note that the fixed value in this case should be set according to the length of the land portion to be recorded.

  In the embodiments so far, in determining whether the sub-data value is “0” or “1”, the reproduction signal level in the mark recording part and the reproduction signal level in the mark non-recording part (the above-described fixed values are used). In other words, in the present invention, the mark recording portion is used for the regular version disc. In addition to the determination using “0” as a threshold value in this way, sub-data on the basis of a predetermined threshold value having an absolute value larger than “0” is considered. It can also be configured to determine the value. That is, for example, the value of the subtraction result (including its integrated value) between the reproduction signal level of the mark recording portion and the reproduction signal level (including the fixed value described above) of the mark unrecorded portion is as described above. When the threshold value that is a positive value larger than “0” is exceeded, the value of the secondary data = “1” is determined. Conversely, when the threshold value is less than the threshold value that is a negative value smaller than “0”, the secondary data is determined. Value = “0”.

1 is a cross-sectional composition of an optical disk recording medium as an embodiment of the present invention. It is a figure for demonstrating the manufacturing process of the optical disk recording medium of embodiment. It is a data structure figure for demonstrating the data structure of the main data recorded with respect to the optical disk recording medium of embodiment. It is a block diagram which shows the structure of the sub data recording apparatus for recording sub data with respect to the optical disk recording medium of embodiment. It is a figure for demonstrating the recording form of subdata. It is a data structure figure which shows the data content which should be stored in a subdata recording device. It is a flowchart for demonstrating the recording operation of the subdata which a subdata recording device performs. It is a block diagram which shows the structure of the reproducing | regenerating apparatus as embodiment. It is a figure for demonstrating reproduction | regeneration operation | movement of subdata. It is a data structure figure which shows the data content which should be stored in the reproducing | regenerating apparatus of embodiment. It is a flowchart for demonstrating reproduction | regeneration operation | movement of the subdata which the reproducing | regenerating apparatus of embodiment performs. It is a characteristic view showing the result of having conducted an experiment about the reproduction signal characteristic in the mark formation part of the optical disc recording medium as an embodiment. It is the figure which showed typically the result of having observed the board | substrate shape in the optical disk recording medium as embodiment in which mark recording was performed. Characteristics of playback signal level at the mark formation part (vs. mark depth / mark reflection) when a mark is recorded on a land of a predetermined length on an optical disc recording medium on which main data is recorded by a combination of pits and lands It is the figure which showed and graphed the result of having calculated (rate) by simulation. It is a figure for demonstrating the optical conditions set in obtaining the calculation result of FIG. It is the figure which showed the result calculated by simulation about the characteristic of the reproduction signal level in the mark formation part at the time of changing mark size and mark depth, and was shown as a graph. FIG. 4 is a cross-sectional view showing a cross-sectional structure of an optical disk recording medium as a diagram for explaining that the optical depth of a mark forming portion is different between a regular version disk and a pirated version disk. As a diagram for explaining that the polarity of the reproduction signal at the mark forming portion differs between the regular version disc and the pirated disc when it is assumed that the reproduction signal level rises without increasing the mark reflectance. 14 is a graph showing the result of calculating the reproduction signal level characteristics (vs. mark depth / mark reflectivity) at the mark forming portion as in FIG. FIG. 18 is a diagram for explaining that the polarity of the reproduction signal in the mark formation portion differs between the regular version disc and the pirated disc when it is assumed that the mark reflectance increases and the reproduction signal level rises. 6 is a graph showing the result of calculating the reproduction signal level characteristic (vs. mark depth / mark reflectivity) at the mark forming portion in the same manner as FIG. If it is assumed that the mark reflectivity is increased, the playback signal level is increased, and the optical depth of the mark portion is the same between the pirated disc and the regular disc, the regular disc and the pirated disc As a diagram for explaining that the polarity of the reproduction signal at the mark formation portion is different, the result of calculating the reproduction signal level characteristics (vs. mark depth / mark reflectance) at the mark formation portion as in FIG. It is the figure shown as a graph. It is a figure for demonstrating the reproduction signal waveform obtained with the optical disk recording medium of this Embodiment. It is a flowchart for demonstrating the operation | movement performed by the determination circuit with which the reproducing | regenerating apparatus of embodiment is equipped. It is a figure for demonstrating the example which a board | substrate deform | transforms according to mark recording.

Explanation of symbols

  1 playback device, 2 spindle motor, 3 IV conversion circuit, 4 matrix circuit, 5 binarization circuit, 6 host computer, 7 network interface, 8 PLL circuit, 9 synchronization detection circuit, 10 address detection circuit, 11 A / D converter , 12 detection pulse generation unit, 12a detection pulse generation circuit, 12b RAM, 13 sub data detection circuit, 14 ECC circuit, 15 inversion circuit, 16 determination circuit, 70 management server, 100 disk, 101 substrate, 102 reflective film, 103 cover layer

Claims (13)

A substrate and at least a reflective film and a cover layer are laminated on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate, and laser light irradiation by recording power is performed. An optical disc recording medium on which sub-data is recorded by a mark formed on the reflective film, wherein a reproduction signal level at the mark forming portion is increased, and the shape of the substrate of the optical disc recording medium is physically changed As a playback device that plays back an optical disk recording medium that is configured so that the playback signal level at the mark formation portion is reduced in the optical disk recording medium generated by transfer,
Reproduction signal generating means for detecting the reflected light of the laser beam by the reproduction power applied to the optical disc recording medium and generating the reproduction signal;
Sub data detection means for detecting the value of the sub data based on the result of detecting the value of the reproduction signal generated by the reproduction signal generation means at a predetermined sampling point;
Judgment to determine whether or not the optical disk recording medium is a regular disk based on the result of determination as to whether or not the value of the sub data detected by the sub data detection means has been obtained with an appropriate polarity Means,
A playback apparatus comprising: The sub data is configured to include actual data having required data contents and at least an error correction code for performing error correction processing on the actual data.
And reversing means for reversing the polarity of the value of the sub data detected by the sub data detecting means,
Including error correction means for performing error correction processing of the actual data based on the error correction code from the value of the sub data supplied from the inversion means;
The determination means is
The error correction means is configured to determine whether or not the error correction processing has been performed correctly, thereby determining whether or not the value of the sub data has been obtained with an appropriate polarity. ,
The reproducing apparatus according to claim 1. The sub data includes identification information unique to each optical disc recording medium and at least an error correction code for performing error correction processing on the identification information.
And reversing means for reversing the polarity of the value of the sub data detected by the sub data detecting means,
Error correction means for performing error correction processing of the identification information based on the error correction code from the sub-data value supplied from the inversion means;
A transmission unit that transmits predetermined information to an external device via a required network;
The determination means is
By determining whether or not the error correction processing is correctly performed by the error correction means, it is determined whether or not the value of the sub data is obtained with an appropriate polarity. Judge whether it is a regular version disc and
If you determine that it is not a regular disc,
The value of the sub data inverted by the inversion means is supplied to the inversion circuit to invert the polarity, and then the error correction processing in the error correction means is performed again, and the identification information obtained thereby is sent to the transmission means Configured to supply against
The transmission means transmits the identification information supplied from the determination means to the external device as the predetermined information.
The reproducing apparatus according to claim 1. The sub-data detecting means is
Detecting the value of the sub-data based on the difference value of the value of the reproduction signal between the recorded portion and the unrecorded portion of the mark detected at the predetermined sampling point;
The reproducing apparatus according to claim 1. The sub-data detecting means is
The difference value of the reproduced signal value between the recorded portion and the unrecorded portion of the mark detected at the predetermined sampling point is obtained, and the value of the sub data is detected based on the integral value of the difference value. To
The reproducing apparatus according to claim 1. The substrate is formed by laminating at least a reflective film and a cover layer on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate, and laser light irradiation by recording power is performed. An optical disk recording medium on which sub-data is recorded by a mark formed on the reflection film, wherein a reproduction signal level at the mark forming portion is increased, and the shape of the substrate of the optical disk recording medium is physically changed As a reproduction method for reproducing an optical disk recording medium configured so that a reproduction signal level at the mark formation portion is reduced in the optical disk recording medium generated by transfer,
A reproduction signal generation procedure for detecting the reflected light of the laser beam by the reproduction power irradiated to the optical disc recording medium and generating the reproduction signal;
A sub data detection procedure for detecting a value of the sub data based on a result of detecting the value of the reproduction signal generated by the reproduction signal generation procedure at a predetermined sampling point;
Judgment to determine whether or not the optical disk recording medium is a regular disk based on the result of determining whether or not the value of the sub data detected by the sub data detection procedure has been obtained with an appropriate polarity Procedure and
A playback method comprising: An optical disc recording medium formed by laminating at least a reflective film and a cover layer on the substrate and recording main data by a combination of pits and lands formed on the substrate. A recording apparatus for recording sub-data by irradiating a laser beam with a recording power and forming a mark on the reflective film.
A mark in which the reproduction signal level in the mark formation portion increases and the reproduction signal level in the mark formation portion decreases in an optical disk recording medium generated by physically transferring the shape of the substrate of the optical disk recording medium. A recording means for recording the sub data by irradiating a laser beam with the recording power so that the mark is formed according to the size and the mark depth;
A recording apparatus. An optical disc recording medium formed by laminating at least a reflective film and a cover layer on the substrate and recording main data by a combination of pits and lands formed on the substrate. A method of recording sub-data by forming a mark on the reflective film by irradiating a laser beam with a recording power for a target,
A mark in which the reproduction signal level in the mark formation portion increases and the reproduction signal level in the mark formation portion decreases in an optical disk recording medium generated by physically transferring the shape of the substrate of the optical disk recording medium. The sub data is recorded by performing laser light irradiation with the recording power so that the mark is formed according to the size and the mark depth.
And a recording method. The substrate is formed by laminating at least a reflective film and a cover layer on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate, and laser light irradiation by recording power is performed. As a disk manufacturing method for manufacturing an optical disk recording medium in which sub data is recorded by the mark formed on the reflective film,
A master disc generating step for generating a disc master disc in which the main data is recorded by a combination of the pits and lands,
A main data recording disk on which only the main data is recorded is produced by generating the substrate by a stamper created based on the master disc and laminating at least the reflective film and the cover layer on the substrate. A disc forming process to be manufactured;
A sub data recording step for recording the sub data on the main data recording disk,
In the sub data recording process,
An optical disc recording medium generated by physically transferring the shape of the substrate of the optical disc recording medium and increasing the reproduction signal level at the mark forming portion when the mark is formed on the land having a predetermined length. Then, the sub-data is recorded by performing laser beam irradiation with the recording power so that the mark is formed with a mark size and a mark depth at which the reproduction signal level at the mark forming portion is reduced.
An optical disc manufacturing method characterized by the above. The substrate is formed by laminating at least a reflective film and a cover layer on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate, and laser light irradiation by recording power is performed. An optical disk recording medium on which sub-data is recorded by a mark formed on the reflective film,
In the optical disc recording medium generated by physically transferring the shape of the substrate of the optical disc recording medium, the reproduction signal level at the mark forming portion is increased for the land having a predetermined length, and the mark forming portion is formed. The mark is formed by the mark size and mark depth at which the reproduction signal level at
An optical disc recording medium characterized by the above.   A substrate and at least a reflective film and a cover layer are laminated on the substrate, and main data is recorded by a combination of pits and lands formed on the substrate, and the main data is recorded. An optical disc recording medium on which sub data whose polarity is determined for a land portion is recorded.   12. The optical disk recording medium according to claim 11, wherein the sub data is recorded by a mark formed by irradiation with laser light having a predetermined recording power.   12. The optical disc recording according to claim 11, wherein the polarity of the value of the sub data is determined using a property that a reproduction signal level of a mark portion formed with respect to the land portion is increased or decreased. Medium.

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