JPH0981938A - Optical disk with illegal copy preventing function and optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discriminate whether a disk is an illegally copied disk by utilizing the presence/absence of a prepit section not located on the center line of a track or the presence/absence of the rocking of the track. SOLUTION: In a partial area of a disk 1, a displaced pit string 7 in which a part of pit strings of a track 5 is displaced in the radial direction is arranged. When a light spot is passed through the displaced pit string 7, the amplitude variation of a reproducing signal is little but a large level variation is generated in a tracking error signal. By utilizing the level variation of the tracking error signal, the presence/absence of the displaced pit string 7 is detected and the disk is discriminated. In a partial area of a disk 51, a track 54 oscillated with higher frequency than the frequency at the intersection of the control gain of tracking control is provided and the disk is discriminated by the level of a rocking frequency component included in the tracking error signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recordable / reproducible optical disc having an information pit string having a disc-specific shape, and whether or not the disc is illegally copied by using the disc-specific information. The present invention relates to an optical disc device that can determine

[0002]

2. Description of the Related Art Optical discs such as compact discs have been used as information transmission means in various fields such as application software for personal computers, databases and music in recent years.

In particular, since a read-only optical disc can be manufactured by transferring information pits from a single master stamper to a plastic plate by injection molding, a large number of optical discs having the same content can be produced at low cost. There are features.

A tracking control method for reading information from an optical disc will be described with reference to the drawings. FIG. 25 is a block diagram of conventional tracking control.

Reference numeral 200 is a disk, 201 is a track,
Reference numeral 202 is a light spot, and 210 is a disk motor for rotating the disk 200. An optical head 211 optically reproduces a signal on the disk 200, and includes a semiconductor laser 212, a collimator lens 213, an objective lens 214, a half mirror 215, a light receiving unit 216, and an actuator 217. 220 is a light spot 20
A tracking error signal detector that detects a tracking error signal indicating the amount of positional deviation between the track 201 and the track 201 in the radial direction, and is composed of a differential circuit 221 and a low pass filter 222. Reference numeral 223 denotes a phase compensation unit that generates a drive signal for driving the optical head from the tracking error signal, 2
Reference numeral 24 denotes a head drive unit that drives the actuator 217 in the optical head 211 based on the drive signal. Reference numeral 225 is an adder circuit for the signal from the light receiving section 216, 226 is a binarization circuit section for binarizing the reproduced signal, and 227 is a signal processing section for demodulating the reproduced signal and converting it into information data.

First, the position control of the light spot in the focus direction (focus direction) is performed, but in the present invention, it is generally assumed that the focus control is realized.

The operation of performing tracking control will be described below. The laser light emitted from the semiconductor laser 212 is collimated by the collimator lens 213 and focused on the disc 200 via the objective lens 214.
The laser light reflected by the disk 200 is the half mirror 2.
The light quantity distribution determined by the relative position between the light spot 202 on the disc and the track 201 is detected as an electric signal by returning to the light receiving portions 216a and 216b via 15. Two
When the divided light receiving units 216a and 216b are used, the differential circuit 221 detects the difference between the light receiving units 216a and 216b, and the low pass filter 222 extracts the low frequency band of the differential signal to obtain the tracking error signal. To be detected. In order to cause the light spot 202 to follow the track 201, the phase compensating unit 223 generates a drive signal so that the tracking error signal becomes 0 (the light amount distributions of the light receiving units 116a and 116b are equal), and according to the drive signal. Head drive unit 22
4 moves the actuator 217 to move the objective lens 214
Control the position of.

On the other hand, the light spot 202 is the track 201.
When the following condition is followed, the amount of reflected light decreases due to light interference in the pit portion of the track, and the output of the light receiving unit decreases, while the amount of reflected light increases in the portion without the pit, and the output of the light receiving unit increases. The total amount of light output from the light-receiving unit corresponding to this pit is obtained by the adder circuit 225, and this reproduced signal is converted into the binarization circuit unit 22.
At 6, a binarized signal and a read clock are generated. This 2
Signal processing unit 22 for demodulating and error correcting the binarized signal
It can be used as information by going through 7.

The information read from the optical disk is transferred to a personal computer or the like and used in the personal computer. However, some or all of the information can be recorded and stored in another recording medium as needed. Generally, the copyright of application software for personal computers is protected by law and cannot be copied without the consent of the right holder. However, since there is a case where the information is illegally copied, the information distributed on the recordable medium may have a copy prevention method of recording and managing the copy management information on the medium.

[0010]

However, since the read-only optical disc can only reproduce the recorded information, the copy management information cannot be stored in the disc itself. Therefore, the contents of the read-only optical disc may be copied without permission to another inexpensive recordable medium and used, which poses a problem in copyright protection.

In view of the above problems, the present invention prevents the reuse of information on a copy disc by adding identification information as the shape of a track to an original disc that is properly distributed under the control of the right holder. The purpose is to do.

[0012]

In order to solve the above problems, the illegal copy prevention optical disk of the present invention is a displacement in which a part of a track constituted by an information pit row is displaced in the radial direction from the track center line. It is characterized in that the pit row is provided in a partial radial area of the optical disc.

Further, in the disc having the displacement pit train, the position information of the displacement pit train and the displacement pattern information of the displacement pit train are recorded in the information pit train.

Further, it has a rocking track region formed by rocking a track constituted by a row of information pits at a predetermined frequency and a predetermined amplitude, and the position information or rocking frequency of the rocking track exists. The information is recorded in the information pit train.

Further, the optical disc apparatus with the illegal copy prevention function of the present invention comprises an optical disc having the displacement pit sequence, a displacement pit sequence detection unit for detecting the presence of the displacement pit sequence from the level fluctuation of the tracking error signal, and Presence / absence of a displacement pit sequence from the output from the displacement position information detection unit and the displacement pit sequence information management unit that reads and stores the displacement position information and displacement pattern information of the displacement pit sequence, and the output from the displacement pit sequence detection unit and the displacement pattern coincidence detection unit. And a disc determination unit that identifies that the displacement patterns match.

Further, an optical disk having the swing track, a swing track detecting section for extracting a swing component from a tracking error signal, an arrangement for reading and storing arrangement position information and swing frequency information in which the swing track exists. It is characterized by comprising a position information detecting section, a swing frequency information detecting section, and a disc determining section for discriminating a disc from an output of the swing track detecting section.

[0017]

According to the present invention, with the above configuration, a unique track shape is formed as an identification signal for each optical disk.
It is possible to identify whether or not the disc to be played back is the original disc and limit the use of data by the illegally copied disc.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical disc with an illegal copy preventing function according to a first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic view of an optical disc with an illegal copy preventing function according to the first embodiment of the present invention. FIG. 1 (a)
In the figure, 1 is a disc, 2 is a lead-in area of the disc, and 3 is a disc identification area having a displacement pit string. 1B is an enlarged view of the disc identification area, where 4 is a pit, 5 is a track formed as a pit row, 6 is a center pit row in which a pit is formed at the center of the track, and 7 is a displacement pit row. , 8 are light spots.

The operation will be described with reference to FIG. Track 5
Are formed as a series of pit rows according to a predetermined modulation rule by cutting (exposure) using a laser in the master stamper manufacturing process for disk manufacturing. During the cutting of the track 5, the cutting laser light is temporarily displaced in the radial direction of the track at a predetermined position to perform the cutting, thereby forming the displacement pit row 7. The displacement amount of the displacement pit train 7 in the track radial direction is within a range that does not significantly affect the reproduction signal of the information represented by the pits, and the displacement of the pit train can be detected as the level fluctuation of the tracking error signal. give.

Generally, the amplitude change ΔRF of the reproduction signal RF with respect to the positional deviation amount Δx between the pit 4 and the light spot 8 is as shown in FIG. 2A, while the position between the pit 4 and the light spot 8 is shown. Tracking error signal T with respect to deviation amount Δx
The amplitude change ΔTE of E is as shown in FIG. That is, since the amplitude change ΔRF of the reproduction signal with respect to the position deviation amount Δx is smaller than the amplitude change ΔTE of the tracking error signal, if the position deviation amount (pit displacement amount) is appropriate, the amplitude change of the reproduction signal does not occur. It is possible to reliably detect the level fluctuation of the tracking error signal within a range that does not affect the reproduction of information.

Considering that the accuracy required for the normal tracking control is about 1/15 of the track pitch TP, the amount of displacement capable of detecting level fluctuation is about 1/15 to 1/8 of the track pitch. Just set the amount.

The normal tracking error signal is an LPF.
Since the signal passes through the (Low Pass Filter), the length of the displacement pit string in the track line direction can be detected as the LP of the tracking error signal in order to detect it as the level fluctuation of the signal after passing the LPF.
The length must be within the F signal band (about 50 kHz or less). Therefore, the length of the displacement pit array 7 in the track line direction may be set to several tens of μsec or more as the transit time of the light spot 8.

Reproduction signal R in the above-mentioned displacement pit train 7
The waveforms of F and the tracking error signal TE are shown in FIG. When the light spot 8 is in the center pit row 9, the tracking error signal TE shows a value near 0 because the light spot 8 is almost at the center of the track 5 by the tracking control.
Further, the reproduction signal RF becomes a signal according to the presence or absence of the pit 4.

Next, when the light spot 8 hits the displacement pit row 7 having the displacement amount Δx, the light spot 8 cannot follow the pit row which is abruptly displaced, so that the light spot 8 and the pit 4 are misaligned. Δx occurs, and the level of the tracking error signal TE suddenly changes by ΔTE. Further, the reproduction signal RF also varies by ΔRF, but does not affect the reproduction.

When the transit time of the displacement pit row 7 is about several tens of microseconds, the light spot 8 returns to the normal center pit row 10 before following the displacement pit row 7, and tracking is performed as shown in FIG. The error signal returns to near 0 again. Therefore, the tracking error signal TE before and after the displacement pit row portion 7 has a waveform as shown in FIG.

Therefore, if a displacement pit train is provided on the original disc, the level fluctuation of the tracking error signal occurs in the displacement pit train portion as described above. On the other hand, when the information in the original disc is copied to another recording medium, it is possible to copy the information obtained from the reproduced signal, but the displacement pit string is not copied. It is possible to identify whether it is a copy disk or a copy disk.

The disc identification area 3 in which the displacement pit row is arranged is used together with the management data area (for example, the TOC area of a CD) of the disc which is always reproduced at the start of the disc reproducing operation so that the disc can be checked without fail when the disc is started up. It is efficient when set to.

Next, a second embodiment will be described. FIG.
[FIG. 8] is a schematic view of a displacement pit row in the second embodiment, showing a case where the displacement directions of the displacement pit row are combined in a prescribed pattern. In FIG. 4, 4 is a pit, 5 is a track, 8 is a light spot, 11, 12 and 13 are central pit rows composed of pits in the center of the track, and 14 and 15
Is a displacement pit row, and 16 is an identification pit portion composed of a plurality of displacement pit rows. Here, two displacement pit rows 1
A case will be described where 4 and 15 are respectively arranged on the outer peripheral side and the inner peripheral side of the disk.

The displacement amount and length of each displacement pit row 14, 15 and the arrangement area of the displacement pit row are the same as in the first embodiment. As shown in FIG. 4, the light spot 8 is first an outer peripheral side displacement pit row ID 114, and then an inner peripheral side displacement pit row ID 21.
If the signal passes through 5, the level fluctuation of the tracking error signal will occur in the displacement pit row as described in the first embodiment. However, since the direction of this level fluctuation changes depending on the pit displacement direction, as shown in FIG. Further, the tracking error signal TE is changed to the positive side and the negative side at the position of the displacement pit row.

Therefore, it becomes possible to identify the pattern of the displacement pit string depending on the level fluctuation state of the tracking error signal. By using a plurality of displacement pit rows to form a pattern, it is possible to reliably separate the level fluctuation of the tracking error signal caused by scratches, dirt, etc. on the disc from the level fluctuation of the tracking error signal caused by the displacement pit rows. . One set of identification pit portions 16 formed by combining a plurality of such displacement pit rows is
It is possible to form an arbitrary pattern by arbitrarily combining the displacement direction and the number of displacement pit rows. For example, when two displacement pit rows ID1 and ID2 are used as a set, a combination of displacement directions (ID1, ID2)
Is (inner circumference, inner circumference), (inner circumference, outer circumference), (outer circumference, inner circumference),
Four displacement patterns (outer circumference, outer circumference) can be selected. In addition,
The length of the center pit row 12 between the displacement pit rows 14 and 15 may be shorter than that of the displacement pit rows 14 and 15, or may be omitted.

Next, a third embodiment will be described. FIG. 5 shows the arrangement information of the displacement pit row in the third embodiment. Reference numeral 31 is a disk, 32 is a lead-in area of the disk, 33 is a management data area in which disk management data is recorded, and 34 is a displacement pit arrangement track in which displacement pits are arranged. 35 is disk management data, 36
Is the disc management data such as the contents of the disc, 37 is the displacement pit information, 38 is the arrangement position information of the displacement pit string, and 39 is
Is displacement pattern information of the displacement pit string. Also, 40
Is a track, and 41 is a displacement pit row or identification pit row.

In this example, the case where the arrangement position information and the displacement pattern information are recorded as the displacement pit information will be described. However, when only the arrangement position information or the displacement pattern information is recorded, the arrangement position information is recorded. If only the information of the position or displacement pattern is effective, it can be realized without losing generality. Particularly, when the arrangement position or the displacement pattern is determined as the disc standard, it is sufficient to record the information not specified in the standard on the disc. Further, this displacement pit information is preferably recorded in a part of the data in the management data area in which the contents of the disc are recorded, so the displacement pit string information is recorded in the management data area 33 of the disc. However, there is no problem even if the displacement pit string information is arranged outside the management data area.

First, in the normal management data area, blocks of management data having the same contents are repeatedly recorded,
The management data can be read no matter where the optical head is in the management data area. In the management data 35, displacement pit information 37 is recorded in addition to the disk management data indicating the contents and position of the disk. The displacement pit information 37 is the arrangement position information 3 indicating the track position (or address number) where the displacement pit string is arranged.
8 and the displacement pattern information 39 (displacement pattern, number, etc.) of the displacement pit row when configuring the identification pit portion.

Then, the track 40 indicated by the arrangement position information is also provided with an identification pit portion 41 constituted by a combination of the displacement pit row or the displacement pit row indicated by the displacement pattern information 39.

On the displacement pit arrangement track 34 indicated by the arrangement position information of the displacement pit information, displacement pit rows (identification pit portions) 41 are arranged at a plurality of positions as shown in FIG. 5C. The displacement pit row (identification pit portion) 41 may be one set, but the portion may become unreadable due to a disk defect or the like. Therefore, a plurality of displacement pit rows (identification pit portion) 41 may be provided on the same track. This is because it is better to arrange them individually.

It should be noted that the displacement pit arrangement track 34 may be one track, or even within a range of several tracks, there is no problem in operation.

According to the second embodiment, it is not necessary to record the displacement pit row in a wider area as compared with the first embodiment.
In addition, since the disc creator can specify an arbitrary displacement pattern at an arbitrary position, it becomes possible to provide disc identification with encryption.

Next, a fourth embodiment will be described. FIG. 6 is a block diagram of a disc with an illegal copy preventing function according to the fourth embodiment. FIG. 6A is an overall view of the disk, 51 is a disk, 52 is a lead-in area of the disk, and 53 is a disk identification area composed of pit train tracks formed by rocking at a prescribed frequency. FIG. 6B is an enlarged view of the disc identification area 53, where 4 is a pit, 8 is a light spot,
Reference numeral 54 is a swing track composed of a pit row.

When the swing frequency fwb of the swing track 54 in FIG. 6B is set to a frequency higher than the band (gain intersection) of the tracking control, the light spot 8 cannot follow the swing of the swing track 54. Therefore, the swing amplitude A becomes the amount of positional deviation. Therefore, the tracking error signal
The fluctuation signal of the oscillation frequency is superimposed.

In order to detect the fluctuation component as a level change of the tracking error signal, the fluctuation component is set to be equal to or less than the LPF band of the tracking error signal detection unit, and is approximately 1 kHz to 20 kHz.
May be set in the range. Further, the swing amplitude A is set to an appropriate amount of about 1/15 to 1/8 of the track pitch TP, as described in the first embodiment, as an amplitude that does not affect the reproduced signal.

The states of the reproduction signal RF and the tracking error signal TE at this time are shown in FIG. The light spot 8 follows the vicinity of the amplitude center of the swing track 54 and cannot follow the swing of the swing track 54. Therefore, a signal level corresponding to the swing amplitude A is generated at the swing frequency fwb in the tracking error signal TE. Further, although the reproduction signal RF also varies in amplitude, it is at a level that does not affect reproduction.

By detecting the signal level of the specific frequency fwb of the tracking error signal generated by the swing track 54, it is possible to discriminate between the original disc and the copied disc.

Similar to the first embodiment, this rocking track is used together with the management data area (for example, the TOC area of a CD) of the disc which is always reproduced at the start of the disc reproducing operation so that it can be checked at the time of disc startup. It is efficient when set to.

Next, a fifth embodiment will be described. FIG. 8 shows the arrangement information of the swing track in the fifth embodiment. Reference numeral 61 is a disk, 62 is a lead-in area of the disk, 63 is a management data area in which disk management data is recorded, and 64 is a track in which rocking tracks are arranged. Reference numeral 65 is disk management data, 66 is disk management data such as the contents of the disk, 67 is rocking track information, 68 is rocking track layout position information, and 69 is rocking frequency information.

In this example, the arrangement position information and the oscillation frequency information are recorded as the oscillation track information. However, in the case where only the arrangement position information or only the oscillation frequency information is recorded. Can be realized without losing generality if only the information on the arrangement position or the oscillation frequency is effective. Particularly, when the arrangement position or the displacement pattern is determined as the standard of the disc, it is sufficient to store the information not defined in the standard in the disc. Further, since the swing track information is preferably recorded in a part of the data of the management data area in which the contents of the disk are recorded, the management data area 63 of the disk is recorded.
The description will be made assuming that the swing track information is recorded in the above, but there is no problem if the swing track information is arranged in a region other than the management data area.

First, in the normal management data area, the fourth embodiment is used.
As described above, the management data 65 is repeatedly arranged, and the rocking track information 67 is recorded in each management data 65 in addition to the disk management data 66. As the swing track information 67, placement position information 68 and swing frequency information 69 where the swing track is placed are recorded.

Arrangement position information 68 in the management data area 63
The track number (or address number) where the swinging track 64 exists is recorded in. Further, the rocking frequency information 69 includes rocking frequency f of the rocking track 64.
Record wb.

The rocking track 64 indicated by the rocking track arrangement position information 68 rocks the pit row at the frequency indicated by the rocking frequency information 69 and a predetermined amplitude.
The oscillating track may be one track, or a plurality of tracks may be provided in succession, but it is not necessary to make the area too wide.

By adopting the disk configuration shown in the fifth embodiment, it is not necessary to provide the rocking track in a wide area, and the disk producer can specify the rocking track at any position at any frequency. It becomes possible to provide the identification with encryption.

Next, a sixth embodiment will be described. FIG. 9 is a schematic diagram of an optical disk device with an illegal copy disk identification function according to the sixth embodiment. In FIG. 9, 1 is an optical disk with the illegal copy prevention function described in the first or fourth embodiment, 4 is a pit on the disk 1, 5 is a track configured as a pit train, 7 is a displacement pit train, and 8 Is a light spot. Further, 70 is a disk motor for rotating the disk 1, 71 is an optical head for optically reproducing a pit signal on the disk 1, and 72 is a light spot 8 and a track 5.
A tracking error signal detection unit for detecting a tracking error signal TE corresponding to the amount of positional deviation in the radial direction, 73 is a differential circuit for taking a differential of the reproduction signal from the optical head 71, 74
Is a low-pass filter that removes high-frequency components of the tracking error signal, 75 is a phase compensating unit that generates a head drive control signal from the tracking error signal, 76 is a head driving unit that drives the optical head, and 77 is a reproduction signal that is generated from the optical head. An adder circuit, a binarization circuit section 78 for binarizing the reproduction signal and data synchronization detection, a signal processing section 79 for demodulating the reproduction signal and reading information, and a reference numeral 80 for a displacement pit row section from the tracking error signal. Displacement pit string detection unit for detection, 8
Numerals 1 and 82 are voltage comparators constituting the displacement pit string detection unit 80, 98 is an OR circuit, and 92 is a disc determination unit for disc identification.

An operation method of the optical disk device configured as described above will be described with reference to FIGS. The optical disc having the displacement pit train of the first embodiment will be described here as an example.

Here, the disk 1 rotates and the track 5
The operation of performing the tracking control in which the light spot 8 follows above is similar to the method described in the conventional example. The process of reading information from the reproduction signal and the process of generating the tracking error signal are also similar to those in the conventional example.

FIG. 10 is a diagram showing the principle of operation of the displacement pit array detecting section 80 which detects the displacement pit array 7 from the tracking error signal.

The displacement pit row may be displaced toward the outer peripheral side with respect to the track center line (a) or may be displaced toward the inner peripheral side (b). When the light spot 8 passes through the displacement pit row 7, as described in the first embodiment, the light spot 8
As a result, the displacement error occurs in the displacement pit row 7, and the tracking error signal rapidly changes in level, as shown in FIG. The level fluctuation direction of the tracking error signal TE at this time differs depending on the displacement direction of the displacement pit row 7. Here, in FIG. 10A, it is assumed that it fluctuates to the positive side, and in FIG. 10B, it fluctuates to the negative side. Therefore, the displacement pit row detection unit 80 can detect the presence of the displacement pit row 7 by comparing the fluctuation level of the tracking error signal TE when passing through the displacement pit row with a preset slice level. Here, the slice level REF (+) is set to detect the displacement in the outer peripheral direction, and the slice level REF (−) is set to detect the displacement in the inner peripheral direction, and the voltage comparator in the displacement pit string detector 80 is set. At 81 and 82, the level is compared with the tracking error signal TE. As a result, DET (+) is detected in synchronization with the outer peripheral displacement pit row 7, and DET (-) is detected in synchronization with the inner peripheral displacement pit row 7, and the presence of the displacement pit row is detected. DET (+) and DET (-) are O
The R circuit 98 inputs an IDDET signal indicating whether or not there is a displacement pit string to the disc determination unit 92.

Here, in the disc determination unit 92, the DET
When neither (+) nor DET (-) is detected (IDDET =
L) recognizes that the displacement pit string does not exist and determines that the disc is not the original disc. On the other hand, DET (+), D
When either one of ET (-) is detected (IDDE
When T = H), it is determined that the disc is an original disc.

9 and 10, the displacement pit string detector 80 has a structure for detecting the level of the tracking error signal TE, but as shown in FIG.
It is also possible to detect a sudden level change in the signal by a differentiating circuit. In FIG. 11, 95 is a differentiating circuit, 96 and 9
Reference numeral 7 is a voltage comparator. The tracking error signal TE is passed through a differentiating circuit 95 to obtain a waveform like a TED signal. This TED signal is the slice level REF2
It is detected by DET2 (+) and DET2 (-) whether or not the positive level has been exceeded by (+) and the negative level has been exceeded by the slice level REF2 (-). That is, DET2 (+) or DET2
The existence of the displacement pit string 7 can be identified by whether or not (-) is detected.

Even in the case where the disc is the optical disc having the swing track of the fourth embodiment, a level change due to the swing occurs in the tracking error signal, and this level change causes the slice levels REF (+) and REF (-). When it exceeds, DET (+),
DET (-) is output. Therefore, the disc determination unit 9
The disc may be identified by the presence or absence of DET (+) and DET (-) outputs in 2.

Next, a seventh embodiment will be described. FIG.
FIG. 14 is a configuration diagram of an optical disk device with an illegal copy disk identification function in a seventh embodiment. In FIG. 12, reference numeral 1 is an optical disk with the illegal copy prevention function described in the second embodiment, 4
Is a pit on the disk 1, 5 is a track configured as a pit row, 8 is a light spot, and 14 and 15 are a displacement pit row ID1 and a displacement pit row ID2 arranged with a displacement pattern. Here, a case will be described as an example where a pattern of a displacement pit array is identified using two displacement pit arrays. 70, 71, 72, 73, 74, 75, 7
6, 77, 78, 79, 80, 81, 82, 92 are the sixth
Similar to the embodiment, in the seventh embodiment, a pattern matching detection unit 83 for newly determining whether the pattern of the displacement pit string matches the predetermined pattern is provided.

An operation method of the optical disk device configured as described above will be described with reference to FIGS.

Here, FIG. 13 shows two displacement pit rows I
D114 and ID215 are the outer peripheral side displacement pit rows,
It shows the case of being configured as an inner circumferential side displacement pit row. As described above, the tracking error signal TE causes a level fluctuation in each displacement pit row, and the displacement pit row detecting unit 80 causes the TE level fluctuation. Detected and DET
(+) And DET (-) are output. Since the discriminating condition of this disc is that DET (+) and DET (-) are detected in a predetermined pattern, in this example, DET (+) is detected first, and then DET ( It is only necessary to detect −). Therefore, in the pattern matching detection unit 83, the predetermined DET (+) and DET (-) output patterns and the DET (+) and DET (-) patterns actually output from the displacement pit string detection unit are output. When they match, a match signal IDDET is output. That is, it may be determined that the disc is the original disc when the coincidence signal IDDET is output. This determination is made by the disc determination unit 92.

Next, the eighth embodiment will be described. FIG.
FIG. 14 is a schematic view of an optical disc device with an illegal copy disc identification function according to an eighth embodiment. In FIG. 14, reference numeral 51 is the optical disk with the illegal copy preventing function described in the fourth embodiment, 4 is a pit on the disk 51, and 54 is a rocking track composed of a row of pits rocked in a radial direction at a predetermined frequency and amplitude. Is. Reference numeral 85 is a swing track detection unit, 86 is a swing track amplitude measurement unit, and 87 is a swing amplitude comparison unit.

Here, 70, 71, 72, 73, 74,
75, 76, 77, 78, 79 and 92 have the same configuration as that of the sixth embodiment and operate in the same manner.

An operation method of the optical disk device having the above-described structure will be described with reference to FIGS.

FIG. 15 shows the principle of operation for detecting the rocking track 54 by the rocking track detector 85.
In the normal track 55 where the track does not swing, the light spot 8 is positioned on the center line of the track, and the tracking error signal has a value near 0.
When the light spot 8 is on the swing track 54, the light spot 8 cannot follow the swing of the track as described above,
The tracking error signal TE as shown in FIG. 15 is detected. The tracking error signal TE is input to the amplitude measuring unit 86 having a frequency characteristic that selectively passes only a specific frequency (oscillation frequency) fwb as shown in FIG. As a result, the output signal Awb of the amplitude measuring unit 86 has a small amplitude in the normal track 55 area and is output as amplitude fluctuation in the swing track 54. Then, the amplitude comparing unit 87 compares whether the Awb signal exceeds a predetermined slice level REFwb, and if it exceeds, outputs the detection signal IDDET. Therefore, when the IDDET is detected, the rocking track exists, and it is determined that the disc is the original disc. This determination is made by the disc determination unit.

The swinging track detecting section 85 can be realized by the configuration shown in FIG. 17 in addition to the configuration of the amplitude measuring section 86 and the amplitude comparing section 87 as shown in FIG. In FIG. 17, 88 is a frequency characteristic measuring unit for measuring a frequency spectrum, and 89 is an amplitude analyzing unit for detecting whether or not there is a frequency component exceeding the reference level.

FIG. 18 shows how the swinging track detecting section 90 operates. The frequency characteristic measuring unit 88 sets an appropriate measurement section, and the tracking error signal TE in this section is set.
Measure the frequency spectrum of. FIG. 18 shows the case of a measurement section 56 on the normal track 55 and a measurement section 57 on the swing track 54. Measurement section 56, 5
The signal component at each frequency is measured at each of 7 and the frequency spectrum is as shown in the figure. Next, the amplitude analysis unit 89 determines the reference amplitude R among the obtained amplitudes of the respective frequency components.
It is checked whether there is a frequency component exceeding EFwb2, and if there is an amplitude that exceeds EFwb2, it is checked whether the frequency is the predetermined swing amplitude frequency fwb. As a result, when the frequency is fwb, it is determined that there is a rocking track, and the detection signal IDDET = H is output (measurement section 57 o'clock). However, all frequency components have the reference amplitude REFwb2
When it is smaller, or when the frequency of the frequency component exceeding REFwb2 does not match the swing frequency fwb, the detection signal IDDET = L is output, indicating that there is no swing track (measurement interval 58 o'clock). .

As described above, the presence or absence of the swing track can be determined by the output of the detection signal IDDET.

Next, a ninth embodiment will be described. FIG.
FIG. 14 is a schematic diagram of an optical disc device with an illegal copy disc identification function according to a ninth embodiment. In FIG. 19, reference numeral 31 denotes the optical disk described in the third embodiment, and the disk management data 36 and the displacement position information 3 of the displacement pit row are stored in the management data area 33.
8 is recorded, and the displacement pit row 41 is formed at the position designated by the arrangement position information 36.

Reference numeral 91 is a position information detecting section for reading the arrangement position information, and 92 is a disc determining section. Also, 70, 7
1, 72, 73, 74, 75, 76, 77, 78, 7
Reference numerals 9 and 80 have the same configuration as that of the sixth embodiment and operate in the same manner.

The operation will be described below with reference to FIGS. FIG. 20 is a flow chart showing the operation of the ninth embodiment. First, when the disc 31 is reproduced, the management data area 31 of the disc is reproduced (s1). In the management data area 31, disk management data 36 indicating the content and position of information recorded on the disk 31 is recorded, and this management data is normally reproduced at the start of reproduction. It is assumed that the disc 31 on which the displacement pit row of the present invention is formed also has the arrangement position information 37 indicating the address position where the displacement pit row is arranged in a part of the management data area 31. Therefore, the position information detecting unit 91 reads out and stores the data (IDADR) regarding the displacement pit row arrangement position information 37 from the reproduced data (s2).

Next, the optical head 71 is moved to the address indicated by IDADR (s3). It is checked whether or not the displacement pit string 41 exists at this address position (s
4). When there is a displacement pit train, the detection signal IDDET from the displacement pit train detector 80 is H, so
When DDET = H, it is determined that the disc is the original disc (s5). On the other hand, if IDDET remains L,
Since it means that there is no displacement pit string, it is judged that the disc to be reproduced is not the original disc (s6). The disc determination unit 92 determines the disc.

In the ninth embodiment, the displacement pit row 41
Although the disc 31 having the above is described, the disc can be determined by the same operation even in the disc 61 in which the swing track is formed at the designated position as in the fifth embodiment. In this case, the position information detector 91 reads the position information 68 of the rocking track while the management data area 63 of the disc 61 is being reproduced.

Further, instead of the displacement pit train detector 88, the swinging track detector 85 (or 90) described in the eighth embodiment is provided, and IDD is set at a designated address position.
Whether or not the disc is the original disc may be determined by whether or not ET becomes H.

Next, a tenth embodiment will be described. FIG.
FIG. 1 is a schematic diagram of an optical disc device with an illegal copy disc identification function according to the tenth embodiment. In FIG. 21, 31 is the third
In the optical disk described in the embodiment, the disk management data 36 and the displacement pattern information 39 of the displacement pit row are recorded in the management data area 33, and the determined track position 34
It is a disc in which a displacement pit string is formed in the pattern indicated by the displacement pattern information.

Reference numeral 93 is a displacement pattern information detecting section for reading the displacement pattern information, and 83 is the same as the pattern matching detecting section of the seventh embodiment. Also, 70, 71, 72, 73, 7
4, 75, 76, 77, 78, 79, 80, 92 are the sixth
The same operation is performed with the same configuration as that of the embodiment.

The operation will be described below with reference to FIGS. FIG. 22 is an operation flowchart of the tenth embodiment. The operation will be described with reference to FIGS.

First, the management data area 33 is reproduced when the disk reproduction is started (s11). At this time, the displacement pattern information (IDPAT) 39 of the displacement pit row recorded in a part of the management data area 33 is read out and stored by the displacement pattern information detection unit 93 (s12). This displacement pattern information (IDPAT) 39 is used as the pattern matching detection unit 8
3 is set as a reference pattern to be compared (s13).
Next, it is checked whether or not the displacement pit string exists at the track position 34 where the displacement pit string is supposed to exist (s14). If the displacement pit string exists in a predetermined pattern, the output IDDET of the pattern matching detection unit 83 becomes H, so it is determined that the disc is an original disc (s1).
5). If IDDET remains L, it means that the designated displacement pit string does not exist and it is determined that the disc is not the original disc (s16). The disc determination unit 92 makes this determination.

The arrangement position information of the displacement pit string of the ninth embodiment and the displacement pattern information of the tenth embodiment may be used for the determination at the same time. That is, it suffices to check whether or not the displacement pit string indicated by the displacement pattern information exists at the position indicated by the arrangement position information of the displacement pit string.

Next, the eleventh embodiment will be described. FIG.
3 is a schematic diagram of an optical disk device with an illegal copy disk identification function according to the eleventh embodiment. In FIG. 23, 61 is the fifth
In the optical disk described in the embodiment, the disk management data 66 and the rocking frequency information 69 of the rocking track are recorded in the management data area 63, and the rocking track 64 is formed at the rocking frequency specified in the rocking frequency information. It is a burned disc.

Reference numeral 94 is a rocking frequency information detecting section for reading rocking frequency information, 85 is a rocking track detecting section described in the eighth embodiment, and 92 is a disk judging section.

Also, 70, 71, 72, 73, 74, 7
5, 76, 77, 78 and 79 have the same configuration as that of the sixth embodiment and operate in the same manner.

The operation will be described with reference to FIGS. FIG. 24 is an operation flowchart of the eleventh embodiment. First, the management data area 63 is reproduced when the disk reproduction is started (s21). At this time, the rocking frequency information (IDFWB) 69 recorded in a part of the management data area 63 is read and stored by the rocking frequency information detecting unit 94 (s).
22). This rocking frequency information (IDFWB) 69 is set as a reference frequency with which the rocking track detection unit 85 compares (s23). Next, it is checked whether or not the swing track exists at the track position where the swing track is supposed to exist (s24). Specified oscillation frequency (IDFW
If the rocking track 64 formed in B) exists, the output IDDET of the rocking track detecting portion 85 becomes H, and it is judged that the disk is an original disk (s25). Also, I
If DDET remains L, it means that the specified swing track does not exist and it is determined that the disc is not the original disc (s26). The disc determination unit 92 makes this determination.

When the amplitude measuring section 86 shown in FIG. 16 is used as the configuration of the swing track detecting section 85, a variable pass frequency fwb is used. When the frequency characteristic measuring unit 88 of FIG. 17 is used, the amplitude analyzing unit 89 may compare the frequencies specified by IDFWB.

The arrangement position information of the swing track of the ninth embodiment and the swing frequency information of the eleventh embodiment may be used for the determination at the same time. That is, it suffices to check whether or not a track having the rocking frequency indicated by the rocking frequency information exists at the position indicated by the rocking track arrangement position information.

[0086]

As described above, according to the present invention, a part of the track formed by the pit row can be detected in the signal band of the tracking error signal and the amount of the read signal can be read from the track center line in the radial direction. The displacement pit row displaced in the above manner is provided in a part of the disc so that the existence of the displacement pit row can be identified by the fluctuation level of the tracking error signal in the displacement pit row part, and the original disc having this displacement pit row , It is possible to distinguish from a copy disk that does not have a displacement pit string. In addition, the arrangement position information / displacement pattern information of the displacement pit string is recorded in a part of the data as identification information unique to the disc, and the presence or absence of the displacement pit string of the specific pattern at the specific position of the displacement pit string is identified. This can further improve the encryption property.

Further, a swing track in which a track composed of a pit row is swung in the radial direction at a specific frequency that cannot be followed by the tracking control and by an amplitude that has little influence on reading a reproduction signal is provided in a part of the disc. By determining the presence or absence of a swing track by the signal level of a specific swing frequency component in the tracking error signal, it is possible to distinguish between the original disc having this swing track and the copy disc having no swing track. And Also, the arrangement position information and frequency information of the rocking track are recorded in a part of the data as identification information unique to the disc,
By examining the signal level of the specific oscillating frequency component at the specific position, the disc can be identified and the encryption can be further enhanced.

[Brief description of drawings]

FIG. 1A is a diagram showing an entire optical disc of a first embodiment, and FIG. 1B is an enlarged diagram of a disc identification area.

FIG. 2 is a diagram showing a relationship between a positional deviation amount and a reproduction signal and a tracking error signal.

FIG. 3 is a diagram showing a response waveform in a displacement pit row portion.

FIG. 4 is a diagram showing a displacement pit row of a second embodiment.

5A is a diagram showing the entire optical disc of the third embodiment. FIG. 5B is a diagram showing a management data area. FIG. 5C is a diagram showing displacement pit arrangement tracks.

FIG. 6A is a diagram showing an entire optical disc of a fourth embodiment, and FIG. 6B is an enlarged diagram of a disc identification area.

FIG. 7 is a waveform diagram of a reproduction signal and a tracking error signal on a swing track.

FIG. 8A is a diagram showing the entire optical disc of the fifth embodiment. FIG. 8B is a diagram showing a management data area. FIG. 8C is a diagram showing rocking tracks.

FIG. 9 is a block diagram of an optical disc device according to a sixth embodiment.

FIG. 10 is a diagram showing a principle of operation of a displacement pit string detection unit.

FIG. 11A is a diagram showing a detection circuit by a differentiating circuit, and FIG. 11B is a diagram showing a detection principle by the differentiating circuit.

FIG. 12 is a block diagram of an optical disk device according to a seventh embodiment.

FIG. 13 is a diagram showing a detection principle according to a seventh embodiment.

FIG. 14 is a block diagram of an optical disc device according to an eighth embodiment.

FIG. 15 is a diagram showing an operation principle of a swinging track detecting portion.

FIG. 16 is a diagram showing frequency characteristics of an amplitude measuring unit.

FIG. 17 is a block diagram of a second implementation example of the swing track detection unit.

FIG. 18 is a diagram showing an operation principle in Implementation Example 2;

FIG. 19 is a block diagram of an optical disk device according to a ninth embodiment.

FIG. 20 is a flowchart of the ninth embodiment.

FIG. 21 is a block diagram of an optical disk device according to a tenth embodiment.

FIG. 22 is a flowchart of the tenth embodiment.

FIG. 23 is a block diagram of an optical disk device according to an eleventh embodiment.

FIG. 24 is a flowchart of the eleventh embodiment.

FIG. 25 is a block diagram showing a tracking control block of a conventional example.

[Explanation of symbols]

 1 disc 2 lead-in area 3 disc identification area 4 pit row 5 track 6 center pit row 7 displacement pit row 8 light spots 9, 10, 11, 12, 13 center pit row 14 displacement pit row ID1 15 displacement pit row ID2 16 identification Pit part 31 Disc 32 Lead-in area 33 Management data area 34 Displacement pit arrangement track 35 Management data 36 Disc management data 37 Displacement pit information 38 Arrangement position information 39 Displacement pattern information 40 Track 41 Displacement pit row or identification pit part 42 Pit 51 disc 52 lead-in area 53 disc identification area 54 rocking track 55 normal track 56, 67 measuring section 61 disk 62 lead-in area 63 management data area 64 rocking track 65 management data 66 disk management data 67 67 Oscillation track information 68 Arrangement position information 69 Oscillation frequency information 70 Disk motor 71 Optical head 72 Tracking error signal detection unit 73 Differential circuit 74 Low pass filter 75 Phase compensation unit 76 Head drive unit 77 Addition circuit 78 2 Quantization circuit section 79 Signal processing section 80 Displacement pit row detection section 81, 82 Voltage comparator 83 Pattern matching detection section 85 Swing track detection section 86 Amplitude measurement section 87 Amplitude comparison section 88 Frequency characteristic measurement section 89 Amplitude analysis section 90 Swing Moving track detection unit 91 Position information detection unit 92 Disc determination unit 93 Displacement pattern information detection unit 94 Oscillation frequency information detection unit 95 Differentiation circuit 96, 97 Voltage comparator 98 OR circuit 200 Disc 201 Track 202 Light spot 210 Disc motor 211 Light Head 212 semiconductor laser 213 Collimator lens 214 Objective lens 215 Half mirror 216a, 216b Light receiving part 217 Actuator 220 Tracking error signal detection part 221 Differential circuit 222 Low pass filter 223 Phase compensation part 224 Head drive part 225 Addition circuit 226 Binarization circuit part 227 Signal processor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinichi Konishi 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Tokai Hayashi, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Yuji Hisakado 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yoshiyuki Miyabata 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Hiroki Exit 1006 Kadoma, Kadoma-shi, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (13)

[Claims] 1. A disc having a track formed of spiral or concentric information pit rows, and a signal fluctuation that can be detected within a tracking error signal band is generated in a part within a specific radius region of the disc. An optical disc with an unauthorized copy protection function, comprising: a displacement pit array obtained by displacing the information pit array in the track radial direction from the center line of the information pit array over the track length. 2. An identification pit portion having a plurality of the displacement pit rows arranged at a predetermined time interval, and a combination of displacement directions of the respective displacement pit rows having a set of displacement pit rows having pattern information. An optical disc with an unauthorized copy protection function according to claim 1. 3. An optical disc with an unauthorized copy prevention function according to claim 1, wherein the optical disc has an area in which position information in which a displacement pit row or an identification pit portion exists is recorded. 4. An optical disc with an unauthorized copy protection function according to claim 2, wherein the disc has an area in which combination information in the displacement direction of each displacement pit row in the identification pit portion is recorded. 5. A disc having a track formed of spiral or concentric information pit rows,
A swing track that is swung in the radial direction at a frequency higher than the control gain intersection of the tracking control and at an amplitude that does not affect the reading of the information signal is provided in a specific radius region of the disk. An optical disc with an illegal copy protection function. 6. The optical disc with an illegal copy preventing function according to claim 5, wherein the optical disc has an area in which the position information of the swing track is recorded. 7. An optical disc with an unauthorized copy prevention function according to claim 5, wherein the optical disc has an area in which the oscillation frequency information of the oscillation track is recorded. 8. A method according to claim 1, 2, 3, 4, 5, 6 or 7.
An optical head that irradiates a light beam onto the optical disc with the illegal copy prevention function described above, receives the reflected light, converts it into an electric signal and outputs it as a reproduction signal, and the light beam radiated onto the optical disc and the optical disc. Tracking error signal detector for outputting the amount of positional deviation from the center line of the information pit row as a tracking error signal, and a displacement pit for detecting the presence of the displacement pit row or the swing track from the level fluctuation of the tracking error signal. An optical disk device comprising: a column detection unit; and a disc determination unit that determines whether or not the disc is a copy disc from the output of the displacement pit column detection unit. 9. The optical disk device according to claim 8, further comprising a displacement pattern coincidence detecting section for detecting whether or not the identification pit section is formed of a pattern of a predetermined displacement pit row. 10. An oscillating track detector for detecting whether or not the fluctuation frequency of the tracking error signal level is the same as the oscillating frequency of the oscillating track. Optical disk device. 11. An arrangement position information detection unit for detecting position information of a displacement pit row or the presence of the rocking track,
11. The optical disc apparatus according to claim 8, further comprising: a disc determination unit that determines whether or not a displacement pit row or a swing track exists at a position indicated by the arrangement position information. 12. A displacement pattern information detecting section for reading and storing displacement pattern information of an identification pit section, and detecting whether or not an appearance pattern of a displacement pit row from a disc matches the contents of the displacement pattern information detecting section. 10. The optical disk device according to claim 9, further comprising a displacement pattern matching detection unit. 13. A swing frequency information detecting section for reading and storing swing frequency information of a swing track, and detecting whether or not a frequency component defined in the swing frequency information exists in a tracking error signal. 11. The optical disk device according to claim 10, further comprising an oscillating track detector.