JP3150255B2 - Optical disc, method of reproducing the same, and reproducing apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk having a duplication preventing function, a method of reproducing the same, a reproducing apparatus, and an optical disk master recording apparatus.

[0002]

2. Description of the Related Art Generally, an optical disc is composed of a master, a master,
A mother and a stamper are manufactured and mass-produced by injection molding. In some cases, a stamper is made directly from the master. An optical disc master is generally coated with a photoresist on a glass substrate whose surface has been polished, exposed to light using a laser beam whose intensity is modulated by the information signal to be recorded, developed, and developed into a signal with irregularities corresponding to the sensitivity. Is formed. Hereinafter, the uneven signal is referred to as a signal pit or simply a pit.

FIG. 11 shows the configuration of a conventional optical disk master recording apparatus, in which a laser optical system for focus control and a beam expander of the recording laser optical system are omitted.
In FIG. 11, 101 is a recording laser, 102 is an optical modulator, 103 is a mirror, 104 is a lens actuator, 105 is a glass plate coated with a photoresist, 1
06 is a spindle motor, 107 is a signal source, and 108 is a recording equalizer. The laser light from the recording laser 101 is converted into an optical modulator 1 by a signal obtained by equalizing a recording signal from a signal source 107 by a recording equalizer 108.
02, the intensity is modulated, the image is formed on the glass plate 105 coated with the photoresist through the objective lens of the lens actuator 104, and the signal pit train is recorded concentrically or spirally on the glass plate 105 by the rotation of the spindle motor 106. I will do it.

An optical disk reproducing apparatus focuses a semiconductor laser on a signal surface of an optical disk, converts the intensity of light reflected from the signal surface into an electric signal using a photodiode or the like (this signal is called an RF signal), and generates a waveform. The signal is shaped, demodulated into a digital signal, digital signal processing is performed, and the original signal is reproduced.

[0005]

However, although an optical disc such as a compact disc has a copy prohibition bit defined, a reproduction apparatus has not conventionally been provided with a copy prevention function. This is because disc media that can be written only once and can be played back by ordinary playback devices are on the market, but they are more expensive than purchasing an optical disc in a regular manner, and that the writing device is expensive and not widely used. Therefore, there was almost no need to take measures against unauthorized duplication. However, as games and the like are recorded on optical discs, the price of optical discs rises along with the rise in software prices, while the price of disc media that can be written only once and reproduced by ordinary playback devices decreases. By going
Since it is cheaper to copy illegally, a copy protection function has been demanded.

An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide an optical disk having a copy preventing function, a reproducing method and a reproducing apparatus thereof, and an optical disk master recording apparatus.

[0007]

According to the present invention, in order to achieve the above-mentioned object, two or more tracks in which a pit row is not provided in a part of recording tracks adjacent in the radial direction of an optical disk are continuously provided. A shift pit row where a part of the recording track is shifted is provided between the recording tracks from the outer peripheral side of the innermost track to the inner peripheral side of the outermost track where no pit row is provided, and the pit row of the recording track is provided. A signal for instructing half-track jumping is recorded immediately before the start of the non-existent portion and immediately before the end of the shift pit row between the recording tracks. The shift pit train between the recording tracks is reproduced by jumping to the side.

According to the present invention, a part of a recording track adjacent in the radial direction of the optical disk is shifted by half a track toward the inner circumferential side or the outer circumferential side, and a part of the track shifted toward the inner circumferential side or the outer circumferential side by a half track is recorded. A signal for instructing half-track jumping is recorded just before the start and immediately before the end, and when the reproducing apparatus detects this jumping signal, the signal is jumped to the inner side or the outer side by a half track and reproduced. .

Further, the optical disk master recording apparatus of the present invention has a recording beam deflecting means, and a control signal to the deflecting means changes the direction of the recording beam by an angle change corresponding to a half of the recording track interval. This is provided with control means for causing the control to be performed.

[0010]

Therefore, according to the present invention, the pit train between recording tracks is formed by half-track jumping immediately before the start of a portion where no pit train is provided on the recording track and immediately before the end of a portion where a signal pit is provided between the recording tracks. Since the instruction signal is recorded, the reproducing apparatus detects this signal and performs half track jumping to reproduce the signal correctly. On the other hand, in a duplicate disc on which a reproduction signal is recorded, when half-track jumping is performed at the pit train between recording tracks, the pit train is not provided between the recording tracks, so that the probability that a regular track is reproduced decreases. Unauthorized duplication can be prevented.

Further, according to the present invention, in a duplicate disc on which a reproduced signal is recorded, if a half-track jumping is performed at a portion originally recorded with a shift of half a track, the portion is not recorded with a shift of a half track. Tracking to a track or the next track reduces the probability that a legitimate track will be reproduced, thereby preventing unauthorized duplication.

Further, according to the optical disk master recording apparatus of the present invention, the optical disk of the present invention can be manufactured by making only slight changes to the conventional apparatus.

[0013]

【Example】

(Embodiment 1) Hereinafter, an optical disc and its reproduction according to a first embodiment of the present invention will be described. FIG. 1 is a front view of an optical disk according to an embodiment of the present invention. In FIG. 1, 1 is an optical disk, 2 is a recording track, 3 is a portion where no pit row is provided on each of the recording tracks 2-2 and 2-3 (hereinafter referred to as a discontinuous portion), and 4 is two or more tracks. This is a shift pit row provided in a discontinuous portion between two recording tracks (in this embodiment, two tracks). FIG. 2 shows the discontinuous portion 3 in an enlarged manner. In FIG. 2, 2
1, -1, 2-2, and 2-3 are recording tracks, 3 is a discontinuous portion of the recording track, and 4 is a shift pit row between the recording tracks. The shift pit row 4 between the recording tracks is separated from the recording tracks by a distance of a half of the track pitch,
That is, it is provided at the center of the adjacent recording tracks 2-2 and 2-3. 5 is a half track jumping signal to the outer circumference side, 6 and 7 are half track jumping signals to the inner circumference side, and 8 is a one track jumping signal to the outer circumference side.

The half track jumping signals 5 and 6 are provided immediately before the start of the discontinuous portion 3, the half track jumping signal 7 is provided immediately before the end of the shift pit row 4, and the one track jumping signal 8 is provided at the discontinuous portion 3. It is provided immediately after the end of the discontinuous portion 3 of the track 2-2 on one track inner circumference side of the outermost track 2-3.

On the other hand, the reproducing apparatus has a function of performing half-track jumping to the outer circumference when the signal 5 is detected, and a function of performing half-track jumping to the inner circumference when the signals 6 and 7 are detected. When 8 is detected, it has the function of storing it for the first time and, when it is detected for the second time, jumping one track in the designated direction.

Next, the operation of this embodiment will be described. If the optical disk 1 on which the signal is formed as described above is not a duplicated one but a regular optical disk, a half-track jumping signal 5 to the outer peripheral side immediately before the start of the discontinuous portion 3 of the recording track 2-2a is generated. Since the signal has been recorded, the reproducing apparatus detects this signal and performs a half-track jump to the outer peripheral side to reproduce the shift pit row 4 between the recording tracks following the recording track 2-2a. Since the half track jumping signal 7 to the inner circumference is recorded immediately before the end of the shift pit row 4 between the recording tracks, the reproducing apparatus detects this signal and performs half track jumping to the inner circumference to record the track. Recording track 2 following shift pit row 4 between
-2a is reproduced. Since the one track jumping signal 8 toward the outer circumference is recorded at the head of the recording track 2-2b, the reproducing device detects and stores this signal.

When the recording track 2-2 is reproduced about one round,
The reproduction track enters the recording track 2-3, and immediately before the start of the discontinuous portion 3 of the track 2-3, the half track jumping signal 6 toward the inner circumference is recorded. Then, the shift pit row 4 is reproduced again following the recording track 2-3b. Shift pit row 4
Immediately before the end of the recording, the half track jumping signal 7 to the inner circumference side is recorded. The reproducing apparatus detects this signal and performs half track jumping to the inner circumference side. -2b is reproduced again. Since the one track jumping signal 8 toward the outer circumference is recorded at the head of the recording track 2-2b, the reproducing device detects this signal 8. Since the reproducing device detects the signal 8 twice, it jumps to the outer circumference of one track to reproduce the recording track 2-3b. In this way, a regular disc is correctly reproduced.

On the other hand, in a duplicate disc on which a reproduction signal of a regular disc is recorded, as shown in FIG. 3, a signal is recorded only on recording tracks, and no signal is recorded between recording tracks. The recording tracks include, in order, the signals of the recording tracks 2-1 and 2-2a of the regular disk, the signal of the shift pit train 4a between the recording tracks, and the recording track 2-2.
b, 2-3a, the signal of the shift pit row 4b between the recording tracks, the signal of the recording track 2-3b are continuously recorded, and the half track jumping signals 5, 6, 7 are further recorded.
a and 7b and the one-track jumping signal 8 are recorded at the above-mentioned predetermined positions, respectively.

When such a duplicate disk is reproduced, a half-track jumping signal 5 to the outer circumference is recorded immediately before the end of the recording track 2-2a, so that the jump is performed to the outer circumference of the half track. Since there is no pit row between the tracks, the inner track or the outer track on which the half track jumping is performed, that is, the recording track 2-
The signal 4a of the shift pit row recorded subsequently to the signal 2a, or the track 2-3a on the outer side of one track.
Signal 4 of the shift pit row recorded subsequently to the signal 4
Play b. Immediately before the end of the shift pit train signals 4a and 4b, the half track jumping signal 7 toward the inner circumference is recorded, so that the reproducing apparatus jumps half the track toward the inner circumference. Since there is no pit row between the tracks, the track on the inner side or the outer side on which the half track jumping is performed is reproduced. That is, the inner track 4a is reproduced by the outer half track jumping by the signal 5, and the outer track 2-2b is reproduced by the inner half track jumping by the signal 7, and FIG. When the outer track 4b is reproduced by the outer half track jumping by 5 and the inner track 2-2b is reproduced by the inner half track jumping by the signal 7, the data is correctly reproduced. , Otherwise it will not play correctly. The probability of correct reproduction is one half.

When the data is correctly reproduced, the one-track jumping signal 8 is recorded at the head of the track 2-2b. The reproducing device detects this signal and stores it. When the signal is correctly reproduced, the signal of the recording track 2-2 is reproduced about one round, and when the signal enters the track 2-3a, the half track jumping signal 6 is reproduced again to the inner circumference side. When the half track jumping is performed on the inner track side, there is no pit row between the tracks. Therefore, the shift pit row recorded following the signal of the inner track or the outer track on which the half track jump is performed, that is, the signal of the recording track 2-2a. Or the signal 4b of the shift pit row of the track 2-3a on the outer circumference side of one track is reproduced. Immediately before the end of the signals of the shift pit trains 4a and 4b, since the half track jumping signal 7 is recorded on the inner circumference side, the reproducing apparatus performs the half track jumping on the inner circumference side. Since there is no pit row between the tracks, the track on the inner side or the outer side on which the half track jumping is performed is reproduced. That is, the semi-track jumping to the inner circumference side by the signal 6 causes the inner track 4
a is reproduced and the outer track 2-2b is reproduced by the second half track jumping to the inner side by the signal 7a, and the outer track is formed by half track jumping to the inner side by the signal 6 4b is reproduced and the signal 7b
When the inner track 2-2b is reproduced by the second half track jumping to the inner circumference by the above, the track is correctly reproduced, and the one-track jumping signal 8 is detected at the head of the track 2-2b. The playback device uses the track 2-2.
Since the one-track jumping signal 8 is detected twice at the beginning of b, jumping is performed to the outer periphery of one track, and the recording track 2-3b is reproduced.

On the other hand, the outer track 4b is reproduced by the inner half track jumping by the signal 6, and the outer track 2-3b is reproduced by the second inner track jump by the signal 7b. In this case, a one-track jumping signal 8 is placed at the beginning of the track 2-3b.
Is detected. As a result, the one-track jumping signal 8 is detected twice, so that the reproducing apparatus jumps to the track 2-4 on the outer peripheral side of one track, and the reproduction of the track 2-3b is not performed, and the reproduction is not performed correctly. The probability of correct reproduction is one half.

As described above, in this embodiment, the discontinuous portion 3 having no pit row is provided in a part of the recording tracks 2-2 and 2-3 adjacent in the radial direction, and the recording track of the discontinuous portion 3 is provided. When a disk having a shift pit row 4 provided between 2-2 and 2-3 is copied, the probability of correct reproduction is one-fourth.
become. When a plurality of such shift pit rows 4 are provided during one rotation, the same number of one-track jumping signals are also provided, and when the same one-track jumping signal 8 is detected twice, one-track jumping is performed. The probability that the disc will be reproduced correctly is reduced by a power of 1/4, and the effect of preventing duplication is further enhanced.

In this embodiment, an example has been described in which a portion of the recording track where no pit row is provided is provided continuously for two tracks. However, when three or more tracks are provided continuously, a half-track jumping is performed. Since the number of times is increased, the probability that the duplicate disc is reproduced correctly by chance is further reduced, and the reproduction is not performed correctly. In this case, the position where the additional pit row 4 is provided is between the outermost track of the innermost track of the discontinuous portion 3 and the innermost track of the outermost track.

(Embodiment 2) Next, an optical disc and a reproducing method thereof according to a second embodiment of the present invention will be described.
The optical disk of this embodiment is almost the same as the optical disks shown in FIGS. 1 and 2, except that the half-track jumping signal 7 recorded immediately before the end of the shift pit train 4 between the recording tracks is different. That is, there is no jumping signal 8. In this embodiment, as shown in FIG. 4, the signal 70 indicating the half-track jumping recorded immediately before the end of the shift pit row between the recording tracks does not specify the jumping direction but simply performs the half-track jumping. Instruct. In addition, the optical disk reproducing apparatus of the present embodiment has a function of performing half-track jumping in a direction opposite to the direction in which the last half-track jumping was performed.

Next, the operation of this embodiment will be described.
For a regular disc that is not a duplicate, the recording track 2-2
Immediately before the start of the discontinuous portion 3, a signal 5 for instructing half-track jumping to the outer peripheral side is recorded. Since the reproducing apparatus detects this signal 5 and jumps to the outer periphery of the half track, the shift pit train 4 between the recording tracks is reproduced following the recording track 2-2a. At this time, the reproducing device stores the fact that the track is half-track jumped to the outer peripheral side. Immediately before the end of the shift pit row 4 between the recording tracks, a signal 70 for instructing half-track jumping without specifying the direction is recorded. In this case, the recording track 2-2b is reproduced following the shift pit row 4 between the recording tracks because the track is half-track jumped inward.

When the recording track 2-2 is reproduced about one round and enters the track 2-3a, the signal 6 indicating the half-track jumping immediately before the start of the discontinuous portion 3 is reproduced again.
Since this signal 6 instructs half track jumping to the inner circumference side, the reproducing apparatus performs half track jumping to the inner circumference side, and reproduces the shift pit row 4 between the recording tracks again after the recording tracks 2-3b. At this time, the reproducing device stores the fact that the track has been half-track jumped inward. Immediately before the end of the shift pit row 4 between recording tracks, a signal 7 for instructing half-track jumping without specifying a direction is provided.
Since 0 is recorded, when the reproducing device detects this signal, it jumps in a direction opposite to the direction in which it is stored, in this case, a half track jumping toward the outer circumference, so that the recording track 2 follows the shift pit row 4 between the recording tracks. -3b is reproduced.

On the other hand, in a duplicate disc on which a reproduction signal of a regular disc is recorded, as shown in FIG. 5, a signal is recorded only on recording tracks, and no signal is recorded between recording tracks. The recording tracks include the signals of the recording tracks 2-1 and 2-2a of the regular disk, the signal of the pit train 4a between the recording tracks, the recording tracks 2-2b and 2
-3a signal, pit train 4b signal between recording tracks,
Signals of the recording tracks 2-3b are continuously recorded, and signals 5, 6, 70, and 70b for instructing half-track jumping are recorded at predetermined positions.

When such a duplicate disc is reproduced, the signal 5 for jumping half a track to the outer circumference is recorded immediately before the end of the recording track 2-2a, so that the jump is made to the outer circumference of the half track. Since there is no pit row between the tracks, the inner track or the outer track on which the half track jumping is performed, that is, the recording track 2
-Pit signal 4 recorded after the signal 2a
a, or the signal 4b of the shift pit row recorded subsequently to the signal of the track 2-3a on the outer circumference of one track. Immediately before the end of the shift pit train signals 4a and 4b, the signal 70 for instructing half-track jumping whose direction is not specified is recorded. Therefore, the reproducing apparatus performs half-track jumping to the inner peripheral side opposite to the immediately preceding jumping direction. I do. Since there is no pit row between the tracks, the track on the inner side or the outer side on which the half track jumping is performed is reproduced. That is, the inner track 4a is reproduced by the half track jumping to the outer side by the signal 5,
When the outer track 2-2b is reproduced by the inner half track jumping by the signal 70, the outer track 4b is reproduced by the outer half track jumping by the signal 5, and the outer track 4b is reproduced by the signal 70. When the track 2-2b on the inner circumference side is reproduced by the half track jumping to the circumference side, the reproduction is performed correctly, but otherwise, the reproduction is not performed correctly. The probability of correct reproduction is one half.

When the signal is correctly reproduced and the signal of the recording track 2-2 is reproduced about one round and enters the track 2-3a, the signal 6 for instructing half-track jumping to the inner peripheral side is reproduced again. When the half track jumping is performed on the inner track side, there is no pit row between the tracks. Therefore, the shift pit row recorded following the signal of the inner track or the outer track on which the half track jump is performed, that is, the signal of the recording track 2-2a. Or the signal 4b of the shift pit row of the track 2-3a on the outer circumference side of one track is reproduced.
Immediately before the end of the signals of the shift pit trains 4a and 4b, the signal 70 for instructing the half track jumping is recorded, so that the reproducing apparatus performs the half track jumping to the outer circumference opposite to the immediately preceding jumping direction. Since there is no pit row between the tracks, the inner track or the outer track on which the half track jumping is performed is reproduced. That is, the inner track 4a is reproduced by the half track jumping to the inner side by the signal 6, and the outer track 2-3b is reproduced by the half track jumping to the outer side by the signal 70. The track 4b on the outer side is reproduced by the half track jumping to the inner side by 6 and the signal 7
When the track 2-3b on the inner circumference side is reproduced by the half track jumping to the outer circumference side by 0, the reproduction is performed correctly. In other cases, the reproduction of the track 2-3b is not performed and the reproduction is not performed correctly. Probability of correct reproduction is 2
It's a fraction.

As described above, in this embodiment, a discontinuous portion 3 having no pit row is provided in a part of the recording tracks 2-2 and 2-3 adjacent in the radial direction. When a disk having a shift pit row 4 provided between 2-2 and 2-3 is copied, the probability of correct reproduction is one-fourth.
become. When a plurality of such shift pit rows 4 are provided during one rotation, the probability of correctly reproducing a duplicated disk is reduced by a power of 1/4, and the effect of preventing duplication is further enhanced.

When three or more discontinuous portions 3 in which no pit row is provided in a part of the recording tracks adjacent in the radial direction are continuously provided, the probability that the duplicated disc is correctly reproduced is further reduced. The effect of preventing is further enhanced.

Also, in the optical discs shown in the first and second embodiments, the discontinuous portion 3 in which no pit row is provided in a part of the recording track adjacent in the radial direction is reproduced a plurality of times. Then, when a duplicate disc is reproduced, the probability of correct reproduction is multiplied by the number of times of reproduction, and the effect of preventing duplication is further enhanced. For example, if you have a duplicate disk
Assuming that the probability of correct reproduction in the case of reproducing twice is 1/4, the probability of reproducing correctly in the case of reproducing twice is 1/16.

On the optical disk, signals are generally recorded spirally from the innermost circumference to the outer circumference. In a CD or the like, a lead-in area is provided at the innermost circumference, and index information of a disc and the like are recorded. In the optical disks shown in the first and second embodiments as well, if a portion where no pit row is provided in the recording track is provided in the innermost peripheral portion corresponding to the lead-in area of the CD, copying at the start of recording is performed. This is desirable because it is possible to determine whether or not the disc has been burned.

(Embodiment 3) Next, an optical disc and a reproducing method thereof according to a third embodiment of the present invention will be described.
As shown in FIGS. 6 and 7, the optical disc of this embodiment is an optical disc in which shift pits are spirally arranged, and a part of recording tracks adjacent in the radial direction is shifted by half a track on the inner circumferential side or the outer circumferential side. It is recorded shifted. In this embodiment, it can be considered that the length of the discontinuous portion 3 in the second embodiment is extended to half a track. 6 and 7, reference numeral 11 denotes an optical disk, reference numeral 12 denotes a recording track, and reference numeral 13 denotes a shift track which is shifted by half a track toward the inner circumference side. Reference numeral 14 denotes a half track jumping signal provided on the recording track 12 immediately before the start of the shift track 13 toward the inner circumference, and reference numeral 15 denotes a half track jumping signal provided immediately before the end of the shift track 13. The shift direction of these signals is determined by which of the shift track 13 and the recording track 12 is shifted.

When reproducing such a regular optical disk 11, a signal 14 for instructing half-track jumping is recorded immediately before the shift track 13 in which the recording track is shifted inward by half a track. The reproducing apparatus reproduces this signal and reproduces the signal by half-track jumping to the inner peripheral side. Thereby, the recording track 12-
After that, the shift track 13-1 is reproduced continuously. Just before the end of the shift track 13-1, the signal 15 for instructing half-track jumping is recorded, so that the reproducing apparatus jumps by half the track toward the outer periphery, and
The recording track 12-2 follows the shift track 13-1
Is played continuously. In this way, a regular disc is correctly reproduced.

On the other hand, as shown in FIG. 8, in a duplicate disc on which a reproduction signal is recorded, a signal is recorded only at the position of a recording track, and no signal is recorded between recording tracks. That is, a signal recorded on the recording track 12, a signal recorded on the shift track 13, and a signal recorded on the recording track 12 are sequentially recorded from the inner peripheral side of the recording track. For this reason, if the signal 14-2 immediately before the start of the shift track 13-2 is detected while the recording track 12-2 is being reproduced and a half-track jump is made to the inner circumference side, no pit row is provided between the recording tracks. Are tracked by the regular track 13-2 or the outer track 13-3. Also, a signal 15-2 immediately before the end of the shift track 13-2.
Is detected and a half track jumping to the inner circumference side is performed.
4 will be tracked. The probability of correctly reproducing all the tracks is ４, and the probability of correctly reproducing the entire disc is 乗 the number of tracks. That is, the probability that the duplicate disc can be reproduced correctly is almost zero, and the duplicate disc cannot be reproduced correctly.

As described above, according to the present embodiment, a legitimate disc is correctly reproduced, but a duplicated disc is not reproduced correctly, and illegal duplication can be prevented.

In this embodiment, an example in which the shift is made to the inner side is shown. However, even if it is shifted by half a track to the outer side, the same is true except that the jumping direction is reversed.

(Embodiment 4) Next, an optical disk reproducing apparatus according to the present invention will be described. FIG. 9 is a block diagram showing an example of the optical disk reproducing apparatus shown in the first embodiment. In FIG. 9, 21 is an optical disk, 22 is an optical pickup, 23 is a spindle motor, 24 is an analog waveform shaping unit, 25 is a digital demodulation unit, 26 is a digital signal processing unit, 27 is a control unit, 28 is a focus servo unit, 29 Denotes a tracking servo unit, and 30 denotes a rotation servo unit.

Next, the operation of the above embodiment will be described. The optical disk 21 is rotated by a spindle motor 23. The semiconductor laser is focused on the signal surface of the optical disk 21 by the optical pickup 22, and the intensity of light reflected from the signal surface is converted into an electric signal by a photodiode or the like, and an RF signal is obtained. The optical pickup 22 is controlled by the focus servo unit 28 so that the signal surface of the optical disk 21 is always focused, and the tracking servo unit 29 is controlled so that the focus of the semiconductor laser follows the signal track. The RF signal is waveform-shaped by an analog waveform shaping unit 24, demodulated into a digital signal by a digital demodulation unit 25, digitally processed by a digital signal processing unit 26, and the original signal is reproduced.

The control unit 27 detects a signal indicating a half-track jumping recorded immediately before the start of the discontinuous portion where no pit row is provided on the recording track and immediately before the end of the portion where the shift pit row is provided between the recording tracks. Then, in response to the signal, the tracking servo unit 29 is instructed to jump to the inner side or the outer side by a half track. The tracking servo unit 29 jumps inward or outward by a half track in response to a command from the control unit 27. The control unit 27 also has a function of storing a signal instructing one-track jumping, and when detecting a signal instructing one-track jumping twice, instructs the tracking servo unit 29 to perform one-track jumping to the outer peripheral side. I do. When a plurality of types of signals for instructing one-track jumping are determined, a signal for instructing one-track jumping is stored for each type, and when a signal of the same type is detected twice, one-track jumping is instructed.

The half-track jumping signal to be half-track jumped may be any signal, but a signal for instructing half-track jumping to the inner side and a signal for instructing half-track jumping to the outer side. It is necessary to determine a signal different from the signal instructing the half track jumping.

(Embodiment 5) Next, an example of the optical disk reproducing apparatus shown in the second embodiment will be described. The configuration of the device is the same as that of FIG. 9, but the controller 27 has a function of storing the direction of the half track jumping. When a half-track jumping signal different from the half-track jumping signal to the inner or outer circumference is detected, the tracking servo unit 29 is instructed to perform half-track jumping in the direction opposite to the stored jumping direction.

(Embodiment 6) Next, an example of the optical disk reproducing apparatus shown in the third embodiment will be described. The configuration of the device is the same as that of FIG. 9, but the control unit 27 detects a signal indicating a half-track jumping recorded immediately before the start and immediately before the end of the shift track shifted to the inner or outer circumference by a half track. Then, in response to the signal, the tracking servo unit 29 is instructed to jump to the inner side or the outer side by a half track. Tracking servo unit 2
9 jumps to the inner side or the outer side by a half track in response to a command from the control unit 27.

The half-track jumping signal for performing the half-track jumping may be any signal, but a signal for instructing half-track jumping to the inner side and a signal for instructing half-track jumping to the outer side. It is necessary to determine a signal different from the signal instructing the half track jumping.

(Embodiment 7) It is difficult to manufacture an optical disk of the present invention by a conventional optical disk master recording apparatus. FIG. 10 is a block diagram showing an example of an optical disk master recording apparatus according to the present invention. The laser optical system for focus control and the beam expander of the laser optical system for recording are omitted. In FIG. 10, 31 is a recording laser,
32 is an optical modulator, 33 is an optical deflector, 34 is a mirror, 35
Is a lens actuator, 36 is a glass plate coated with photoresist, 37 is a spindle motor, 38 is a signal source, 39 is a recording equalizer, and 40 is a control unit.

Next, the operation of the above-described optical disk master recording apparatus will be described. The laser light from the recording laser 31 is intensity-modulated by an optical modulator 32 by a signal obtained by equalizing a recording signal from a signal source 38 by a recording equalizer 39, appropriately deflected by an optical deflector 33, and The image is formed on a glass plate 36 coated with a photoresist through an objective lens of
With the rotation of 7, a shift pit row is recorded spirally on the glass plate 36. The optical deflector 23 is an element that changes the direction of a laser beam according to a signal, and is an AO modulator using an acousto-optic effect or an EO deflector using an electro-optic effect (for example, a model 310 manufactured by Conoptics).
A and 311A) are commercially available. The control unit 40 sends a signal to the optical deflector 33 to change the direction of the laser beam.
When recording a recording track spirally, the optical deflector 33
The optical deflector 3 is used only when recording a shift pit row or a shift track shifted half an inner track or an outer track with respect to a recording track between recording tracks without transmitting a signal.
3 to change the direction of the recording beam. When the laser beam whose direction has been changed is incident on the lens actuator 24, the position narrowed down in the lateral direction by a distance determined by the product of the incident angle and the focal length of the lens changes.
For example, if the focal length of the lens is to be shifted by 0.8 micron and the focal length of the lens is 2 mm, the angle should be changed to 0.4 milliradian to be incident on the lens.

The shift pit train between the recording tracks may be recorded by shifting the recording beam to the outer periphery when recording the inner recording track, or by recording the recording beam when recording the outer recording track. May be recorded shifted to the inner circumference side.

When recording a part of the recording track by shifting it by a half track, the recording beam may be shifted in a direction to shift the recording track.

As described above, the optical disk master recording apparatus of the present invention can easily record the optical disk of the present invention simply by adding a simple configuration to the conventional apparatus.

Further, the optical disk of the present invention can be manufactured in exactly the same steps as the conventional optical disk except for recording of the master, so that it can be manufactured in large quantities at low cost.

Further, in the optical disk and the optical disk reproducing apparatus of the present invention, the reproduction of the duplicated disk can be disabled, and the duplication of the optical disk can be prevented.

[0053]

As is apparent from the above embodiment, the present invention uses an optical disk in which a part of a regular recording track is shifted to a position between recording tracks, and the start and end positions of the position are used. Since a signal for designating half-track jumping is recorded on the copied optical disk, the normal recording track and the shifted track are reproduced, so even if the duplicated optical disc is half-track jumped, there is no target track. Since the legitimate track reproduces the next track, and the probability that the legitimate track is reproduced becomes low, illegal duplication can be prevented.

Further, according to the optical disk master recording apparatus of the present invention, the optical disk of the present invention can be manufactured by slightly modifying the conventional apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic front view of an optical disc according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged view of a recording track of the optical disc in the first embodiment.

FIG. 3 is a partially enlarged view of a duplicate optical disc in the first embodiment.

FIG. 4 is an enlarged view of a recording track portion of an optical disc in a second embodiment of the present invention.

FIG. 5 is a partially enlarged view of a duplicate optical disc in a second embodiment.

FIG. 6 is a schematic front view of an optical disc according to a third embodiment of the present invention.

FIG. 7 is an enlarged view of a recording track portion of an optical disc in a third embodiment.

FIG. 8 is an enlarged view of a recording track portion of a duplicate optical disc in a third embodiment.

FIG. 9 is a block diagram showing an example of an optical disk reproducing apparatus according to the present invention.

FIG. 10 is a block diagram showing an example of an optical disk master recording apparatus according to the present invention.

FIG. 11 is a block diagram showing an example of an optical disk master recording apparatus in a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Optical disk 2 Recording track 3 Part in which pit row of recording track is not provided (discontinuous part) 4 Shift pit row between recording tracks 5, 6, 7, 70 Half track jumping signal 8 1 track jumping signal 11 Optical disk 12 Recording track 13 Shift track recorded by shifting by half a track 21 Optical disk 22 Optical pickup 23 Spindle motor 24 Analog waveform shaping unit 25 Digital demodulation unit 26 Digital signal processing unit 27 Control unit 28 Focus servo unit 29 Tracking servo unit 30 Rotary servo unit 31 Recording laser Reference Signs List 32 light modulator 33 light deflector 34 mirror 35 lens actuator 36 glass plate coated with photoresist 37 spindle motor 38 signal source 39 recording equalizer 40 control unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B ^7/ 00-7/013 G11B 7/24

Claims (11)

(57) [Claims] 1. A pit row-free portion is provided continuously in two or more tracks in a part of recording tracks adjacent in the radial direction, and the outermost track from the outermost side of the innermost track of the portion where the pit row is not provided. A shift pit row in which a part of the recording track is shifted is provided between the recording tracks up to the inner peripheral side of the recording track, and the shift pit row of the recording track where the pit row is not provided is provided immediately after the start.
Before and immediately before the end of the shift pit train between recording tracks.
An optical disc on which a signal for instructing half track jumping is recorded . 2. The optical disk according to claim 1, wherein a plurality of shift pit rows between recording tracks are provided during one rotation. 3. A process according to claim, characterized by recording a signal indicative of one track jumping the recording track immediately after the end of one track in the peripheral portion of the outermost peripheral portion without the pit train recording track 1 An optical disc as described. 4. The optical disk according to claim 3 , wherein a plurality of shift pit rows between recording tracks are provided during one rotation, and the same number of signals instructing one track jumping are provided. 5. A signal for instructing half-track jumping to the inner or outer circumference is recorded immediately before the start of a portion of the recording track where no pit row is provided, and immediately before the end of the shift pit row between recording tracks. 3. The optical disk according to claim 1, wherein a signal for instructing half-track jumping, which does not indicate a direction, is recorded. 6. The disk according to claim 1, wherein a portion of the recording track where no pit row is provided is provided on an inner peripheral portion of the disk.
6. The optical disc according to any one of claims 1 to 5 , 7. The optical disk according to any one of claims 1 to 6, characterized in that the shift pit rows between the recording tracks to reproduce a plurality of times. 8. A light beam according to claim 1, wherein a part of the recording tracks adjacent in the radial direction is shifted by half a track toward the inner circumference side or the outer circumference side. > Disk. 9. The method of claim 8, characterized by recording a signal indicative of a half track jumping immediately before completion of the immediately preceding the start of the portion which is shifted in the half tracks circumferential side or outer circumferential side
An optical disc as described. 10. An optical disc reproducing apparatus having a function of, when reproducing a signal instructing half-track jumping, jumping inward or outward by a half track according to the signal. 11. The apparatus according to claim 10, further comprising a function of jumping inward or outward by one track according to the signal when a signal instructing one track jumping is reproduced twice. An optical disc playback device.