Optical disk medium, optical disk device

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to an optical disk medium such as a CD (Compact Disc) or a DVD (Digital Video Disc), and an optical disk device that executes at least one of recording and reproduction of information on such an optical disk medium.

【0002】

[Conventional technology]

In recent years, an optical disc medium has been developed as a large-capacity recording medium, and a CD has been put into practical use as one of the typical examples. This is a playback-only recording medium that records audio signals as digital data, but nowadays, CD-WO (CD-Write Once) that allows additional writing of digital data and CD-RAM (CD-RAM) that allows rewriting of digital data. CD-Random Access Memory) etc. have also been put into practical use.

【0003】

As the control method of the rotation speed of the optical disk, there are the CAV (Constant Angular Velocity) method in which the angular velocity is constant with an emphasis on the access speed and the CLV (Constant Linear Velocity) method in which the linear velocity is constant with an emphasis on the recording capacity. There is. In the various CDs mentioned above, the CLV method is adopted because the purpose was originally to reproduce music, and a spiral track is optically scanned at a constant linear velocity.

【0004】

In the case of a playback-only CD-DA (Digital Audio), CLV control is realized by synchronizing the rotation speed with the playback frequency of digital data, but in the case of CD-WO and CD-RAM, the track is digital in the initial state. Since no data has been recorded, CLV control as described above is not possible. Therefore, in the case of a CD-WO or the like, a groove indicating the position of a track is wobbled at regular intervals corresponding to address information, and a wobble signal is reproduced from the tracking signal of the groove to execute CLV control.

【0005】

For example, as shown in FIG. 10, in the case of the CD-WO1 which is an optical disk medium, in order to form a spiral track in which information is recorded and reproduced, the grooves 2 serving as the track are formed at a predetermined pitch. , This groove 2 is wobbled corresponding to the address information. Land 3 is located in such a gap between grooves 2, but this land 3 is not used as a truck.

【0006】

More specifically, as shown in FIG. 11, the address information consists of binary data, is converted into a biphase code, and then is converted into a wobble signal by FM (Frequency Modulation) modulation. In this case, the address information "0" is converted to the bi-phase code "0,0", and the address information "1" is converted to the bi-phase code "1,0". Then, the biphase code "0" is converted into a sine wave with a frequency of "21.05 (kHz)" by FM modulation, and the biphase code "1" is a sine wave with a frequency of "23.05 (kHz)" by FM modulation. Is converted to.

【0007】

When the optical disk device records and reproduces information on such an optical disk medium 1, the optical head optically scans the groove 2. Since this groove 2 is wobbled at a frequency that is probably different from the tracking error, the tracking signal is a superposition of the tracking error signal and the ATIP (Absolute Time In Pregroove) wobble signal.

【0008】

Therefore, as shown in FIG. 12, the address reproduction circuit 4 of the optical disk device extracts the ATIP wobble signal from the tracking signal by the bandpass filter 5, and the ATIP wobble signal is 22.05 (kHz) by the frequency detector 6. The biphase code is restored by binarizing with the threshold. Therefore, since the address information is decoded from this bi-phase code, if the rotation speed of the optical disk medium 1 is controlled in synchronization with this address information, the groove 2 moves at a constant linear speed with respect to the optical head. become.

【0009】

[Problems to be Solved by the Invention]

Since the optical disk media such as the above-mentioned various CDs record the address information by wobbling the track, it is not necessary to use the track recording area to record the address information, and the track recording area is used as data. It can be fully used for recording.

【0010】

However, even with such an optical disc medium, it is not possible to record long-time image data with high quality, and further expansion of the storage capacity is required. It can be assumed that the tracks are arranged at high density, but if the wobbling tracks are arranged at high density, the tracks adjacent to the laser spot that optically detects the tracks interfere with each other, so the S / N ratio of the tracking signal ( Signal-to-Noise ratio) decreases.

【0011】

In order to solve this, it can be assumed that the wobbling amplitude of the track is also compressed in proportion to the array pitch, but this reduces the C / N (Carrier-to-Noise ratio) of the wobble signal and address information. Restoration accuracy is reduced. That is, in the current optical disc medium, it is difficult to increase the density of the track arrangement and expand the recording capacity while achieving both the S / N of the tracking signal and the C / N of the wobble signal.

【0012】

[Means for solving problems]

The optical disk medium of the invention according to claim 1 is an optical disk medium in which tracks are wobbling corresponding to address information, and the tracks are wobbling corresponding to a wobble signal whose address information is phase-modulated. Therefore, when the track of the optical disk medium is optically scanned to record or reproduce the information, the address information is restored by extracting the wobble signal from the tracking signal and detecting the phase. Since phase modulation has a lower error rate and higher S / N and C / N than frequency modulation and amplitude modulation, address information can be restored well even if the wobbling amplitude of the track is shortened. As such an optical disc medium, play-only, write-once type, rewrite type, etc. are allowed, and as the track, pit rows, grooves, lands, etc. are allowed.

【0013】

In the invention according to claim 2, in the optical disk medium according to claim 1, the address information is converted into a predetermined code and then phase-modulated. Therefore, for example, the frequency of occurrence of one of the two values of phase modulation by this code conversion. And the frequency of the carrier wave is adjusted. As such a predetermined code, for example, a bi-phase code or a Manchester code is allowed.

【0014】

In the invention according to claim 3, in the optical disk medium according to claim 1 or 2, since 1 bit of the address information corresponds to the integer period of the wobble signal, the duty ratio of the wobble signal whose address information is phase-modulated is constant. Is.

【0015】

In the invention according to claim 4, in the optical disk medium according to claim 1 or 2, since the binary value of the address information corresponds to the phase of "0" degree and "180" degree of the wobble signal, the wobble signal Even if the phase is inverted, the amplitude between the start point and the end point becomes "0", and even if the binary value of the address information changes, the wobbling track continues without interruption.

【0016】

In the invention according to claim 5, in the optical disk medium according to claim 1 or 2, since the binary value of the address information and the phase of the wobble signal have a one-to-one correspondence, the address information can be detected by detecting the phase of the wobble signal. The binary value of is restored.

【0017】

In the invention according to claim 6, in the optical disk medium according to claim 1 or 2, since the binary value of the address information and the presence / absence of phase inversion of the wobble signal have a one-to-one correspondence, the phase inversion of the wobble signal is inversion. If the presence or absence of is determined, the binary value of the address information is detected.

【0018】

In the invention according to claim 7, in the optical disk medium according to claim 6, since the phase of the wobble signal is inverted in response to the occurrence of one of the binary values of the address information, the phase of the wobble signal is inverted. If the presence or absence is determined, the binary value of the address information is detected.

【0019】

In the invention according to claim 8, in the optical disk medium according to claim 1 or 2, since the frequency of the carrier wave for phase modulation of address information is located between the tracking servo band and the RF signal band, the wobble signal and the tracking error signal And the RF signal are reproduced separately without interfering with each other.

【0020】

The optical disk device of the invention according to claim 9 has a rotation drive mechanism for rotationally driving an optical disk medium in which a track is wobbled in response to address information, and an optical scan of the rotating track of the optical disk medium to detect at least a tracking signal. It has an optical head, a bandpass filter that extracts a wobble signal of a specific frequency band from a tracking signal, and a phase detector that detects the phase of the wobble signal and restores address information. Therefore, when the track wobbled corresponding to the address information of the optical disk medium is optically scanned to record or reproduce the information, the optical disk medium is rotationally driven by the rotation drive mechanism, and the rotating track of the optical disk medium is optically driven. The tracking signal is detected by optical scanning by the head. A bandpass filter extracts a wobble signal in a specific frequency band from this tracking signal, and the phase of the wobble signal is detected by a phase detector to restore address information. That is, even if the track of the optical disk medium is wobbling corresponding to the wobble signal whose address information is phase-modulated, the wobble signal is extracted from the tracking signal and the address information is restored. Compared to frequency modulation and amplitude modulation, phase modulation has a lower error rate and higher S / N and C / N, so even if the wobbling amplitude of the optical track is shortened, the address information is restored well. To. Such optical disk devices include a disc recorder that records information on an optical disk medium, a disc player that reproduces information on an optical disk medium, a disk eraser that erases information on an optical disk medium, and a disk eraser that records, reproduces, or erases information on an optical disk medium. Allow disk drives, etc. to run.

【0021】

The optical disk device of the invention according to claim 10 has a rotation drive mechanism for rotationally driving an optical disk medium in which a track is wobbled in response to address information, and an optical scan of the rotating track of the optical disk medium to detect at least a tracking signal. An optical head to be used, a bandpass filter that extracts a wobble signal of a specific frequency band from a tracking signal, a delay circuit that delays the wobble signal by a predetermined time, and a product that superimposes the delayed signal on an undelayed wobble signal. It has a circuit and a low-pass filter that smoothes the product signal. Therefore, when the track wobbled corresponding to the address information of the optical disk medium is optically scanned to record or reproduce the information, the optical disk medium is rotationally driven by the rotation drive mechanism, and the rotating track of the optical disk medium is optically driven. The tracking signal is detected by optical scanning by the head. A bandpass filter extracts a wobble signal of a specific frequency band from this tracking signal, and the wobble signal is delayed by a delay circuit for a predetermined time. This delay signal is multiplied by the undelayed wobble signal by the product circuit, and the product signal is smoothed by the low-pass filter. That is, even if the track of the optical disk medium is wobbled so that the binary value of the address information and the presence or absence of the phase inversion of the wobble signal correspond one-to-one, the wobble signal is extracted from the tracking signal and the address information is obtained. It will be restored. Compared to frequency modulation and amplitude modulation, phase modulation has a lower error rate and higher S / N and C / N, so even if the wobbling amplitude of the optical track is shortened, the address information is restored well. To.

【0022】

The optical disk device of the invention according to claim 11 has a rotation drive mechanism for rotationally driving an optical disk master, an optical head that optically scans the rotating optical disk master to form a track, and a relative relationship between the optical head and the optical disk master. A rotation control circuit that controls the rotation speed of the rotation drive mechanism according to the address information of the track so that the speed becomes constant, and a phase modulator that phase-modulates the address information of the track of the optical disc master to generate a wobble signal. And a head control circuit that reciprocates the scanning position of the optical head in the radial direction of the optical disc master in response to the wobble signal. Therefore, when a wobbling track corresponding to the address information is formed on the optical disc master, the optical disc master is rotationally driven by the rotation drive mechanism, and the track is formed on the rotating optical disc master by the optical head. At this time, the rotation speed of the rotation drive mechanism is controlled by the rotation control circuit corresponding to the address information of the track, and the relative speed between the optical head and the optical disk master becomes constant. Further, the address information of the track of the optical disc master is phase-modulated by the phase modulator to generate a wobble signal, and the scanning position of the optical head is reciprocated in the radial direction of the optical disc master by the head control circuit in response to the wobble signal. To. That is, since a wobbling track is formed on the optical disc master in response to a wobble signal whose address information is phase-modulated. Therefore, when an optical disc medium is manufactured from this optical disc master, the track of this optical disc medium also phase-modulates the address information. The wobbled shape corresponds to the wobble signal. When the track of the optical disk medium is optically scanned to record or reproduce the information, the wobble signal is extracted from the tracking signal and the address information is restored. Compared to frequency modulation and amplitude modulation, phase modulation has a lower error rate and higher S / N and C / N, so even if the wobbling amplitude of the track on the optical disc master is shortened, the address information is restored well. To. As an optical disc master, it is as it is

【0023】

In the invention according to claim 12, in the optical disk device according to claim 11, the phase modulator inverts the phase of the wobble signal in response to the occurrence of a predetermined binary value of the address information. There is a one-to-one correspondence between the value and the presence or absence of phase inversion of the wobble signal.

【0024】

BEST MODE FOR CARRYING OUT THE INVENTION

The first embodiment of the present invention will be described below with reference to FIGS. 1 to 5. Regarding the present embodiment, detailed description of the same parts as those of the above-described conventional example will be omitted by using the same names and reference numerals.

【0025】

As shown in FIG. 2, the optical disk system 11 of the present embodiment includes an optical disk medium 12 and a disk drive 13 which is an optical disk device. The optical disk medium 12 of the present embodiment is formed here as a rewrite type of the CLV method, and the groove 2 serving as the track is wobbling corresponding to the address information. This wobbling phase-modulates the address information. It corresponds to the wobble signal. In this optical disk medium 12, one bit of the address information corresponds to two cycles which are integer cycles of the wobble signal, and the binary value "0/1" of the address information is "0/180" degree of the wobble signal. There is a one-to-one correspondence with the phases of. The carrier wave of this phase-modulated wobble signal is a cosine wave, and its frequency is located between the tracking servo band and the RF signal band.

【0026】

The disk drive 13 of the present embodiment that records and reproduces information on such an optical disk medium 12 has a rotation drive mechanism 14, an optical head 15, a head control circuit 16, a rotation control circuit 17, and the like as main parts. doing. The rotation drive mechanism 14 includes a turntable 18 that holds the optical disk medium 12, a spindle motor 19 that rotationally drives the turntable 18, and the like. As will be described in detail later, the optical disk medium 12 is a CLV system. It is driven to rotate with.

【0027】

The optical head 15 has a laser light source, an objective lens, a beam splitter, a light receiving element, and the like, and optically scans the groove 2 of the optical disk medium 12 to record and reproduce information. The optical head 15 is movably supported in the tracking direction by a sledge mechanism, and inside the optical head 15, the objective lens is movably supported in each direction by a tracking mechanism and a focusing mechanism.

【0028】

The head control circuit 16 is connected to the optical head 15 and executes various information processing related to recording and reproduction of information by the optical head 15. That is, the output signal of the light receiving element is detected, and the laser light source, the sledge mechanism, the tracking mechanism, and the focusing mechanism are driven and controlled. For example, when recording information, the laser light source of the optical head 15 is driven in response to the information to be recorded while executing tracking control and focusing control. Similarly, when the information is reproduced, the RF signal is decoded from the output signal of the light receiving element of the optical head 15 while the tracking control and the focusing control are executed.

【0029】

The head control circuit 16 also has an address reproduction circuit 21 that reproduces the address information of the groove 2 of the optical disk medium 12, and the address reproduction circuit 21 includes a bandpass filter 5 and a phase detection as shown in FIG. It has a vessel 22 and. When the head control circuit 16 executes the tracking control of the optical head 15 as described above, the tracking signal detected by the optical head 15 is also input to the address reproduction circuit 21. In that case, the bandpass filter 5 extracts a wobble signal of a specific frequency band from the tracking signal, and the phase detector 22 detects the phase of the wobble signal and restores the address information.

【0030】

The rotation control circuit 17 is connected to the head control circuit 16 and the spindle motor 19, and corresponds to the address information input from the address reproduction circuit 21 of the head control circuit 16 of the spindle motor 19. The rotation speed is controlled by the CLV method. More specifically, the rotation control circuit 17 has a PLL (Phase Locked Loop) circuit, and generates a target speed for rotational drive of the optical disk medium 12 from the address information input from the head control circuit 16. , The rotation speed of the spindle motor 19 is matched with the target speed by PLL control.

【0031】

In such a configuration, in the optical disk system 11 of the present embodiment, the optical disk medium 12 can be interchangeably loaded in the disk drive 13, and information can be recorded in the optical disk medium 12 thus loaded by the disk drive 13. Playback can be performed.

【0032】

In that case, the optical disk medium 12 is rotationally driven by the rotational drive mechanism 14 of the disk drive 13, and the optical head 15 first records and reproduces information in the groove 2 of the rotating optical disk medium 12. At this time, since the head control circuit 16 detects a tracking signal and a focusing signal from the output signal of the optical head 15 that optically scans the wobbled groove 2, the optical head 15 is made to follow the groove 2 according to these signals.

【0033】

At the same time, the head control circuit 16 detects the wobble signal from the tracking signal and outputs it to the rotation control circuit 17, so that the rotation control circuit 17 feedback-controls the rotation speed of the spindle motor 19 so that the frequency of the wobble signal becomes constant. By doing so, the linear velocity of the optical disk medium 12 with respect to the optical head 15 is made constant.

【0034】

In the optical disk system 11 of the present embodiment, since the groove 2 which is the track of the optical disk medium 12 is wobbled corresponding to the wobble signal whose address information is phase-modulated, the address information is reproduced by the same method as the conventional method. Not done. Therefore, the address reproduction circuit 21 extracts a wobble signal of a specific frequency band from the tracking signal by the bandpass filter 5, detects the phase of the wobble signal by the phase detector 22, and restores the address information.

【0035】

In the optical disk system 11 of the present embodiment, as described above, the wobbling of the groove 2 of the optical disk medium 12 corresponds to the wobble signal whose address information is phase-modulated, and the disk drive 13 corresponds to the wobble signal detected from the optical disk medium 12. Detects the phase of and restores the address information. In this way, the binary address information is phase-shifted into two types of phases of the wobble signal, and the phase of this wobble signal changes discretely to "0/180" degrees, so this phase modulation is PSK. It can also be said to be (Phase Shift Keying) modulation. As shown in Fig. 4, this PSK method has a lower error rate than the conventional FSK (Frequency Shift Keying) method and ASK (Amplitude Shift Keying) method that demodulate address information from the frequency of the wobble signal. High S / N and C / N.

【0036】

In other words, in the disk system 11 of the present embodiment, since the address information is phase-modulated to generate a wobble signal, the groove of the optical disk medium 12 is maintained while securing the C / N and the like necessary for reproducing the address information. The amplitude of wobbling in 2 can be shortened. If the wobbling amplitude of the groove 2 is shortened in this way, the S / N of the reproduced signal does not decrease even if the array pitch of the groove 2 is increased, so that the optical disk medium 12 maintains the S / N of the signal reproduction. The recording capacity can be expanded.

【0037】

In particular, since the optical disk medium 12 of the present embodiment has a one-to-one correspondence between the binary value of the address information and the phase of the wobble signal, the disk drive 13 simply detects the phase of the wobble signal to obtain the address information. The binary value can be restored, and the address information can be reproduced at high speed by the address reproduction circuit 21 having a simple structure.

【0038】

Also, since the binary value "0/1" of the address information corresponds to the phase of "0/180" degrees of the wobble signal, as shown in Fig. 1, even if the phase of the wobble signal is inverted, it will be the starting point. The amplitude with the end point is "0", and even if the binary value of the address information changes, the wobbled groove 2 continues without interruption. When such a groove 2 is actually formed and the wobble signal is detected, as shown in the figure, the waveform of this wobble signal becomes dull at the position where the phase is inverted, but there is no problem due to this.

【0039】

Moreover, in the optical disk medium 12 of the present embodiment, since one bit of the address information corresponds to two cycles of the wobble signal, the duty ratio of the wobble signal does not change with respect to the binary value of the address information. Therefore, unlike a conventional CD, it is not necessary to convert the address information into a biphase code before converting the address information into a wobble signal in order to reduce the duty ratio difference, and the disk drive 13 directly converts the wobble signal into the address information. Since it can be converted to, the load of this processing is small and the speed is high. Since the duty ratio of the wobble signal is constant in this way, it is not necessary to consider the influence of the DC (Direct Current) component of the wobble signal when reproducing the address information, and the disk drive 13 can easily obtain the address information from the wobble signal. Can be played.

【0040】

However, the present invention is not limited to the above-mentioned embodiment, and various modifications are allowed. For example, as shown in FIGS. 5 and 6, it is also possible to generate a wobble signal by converting the address information into a predetermined code such as a biphase code or a Manchester code and then performing phase modulation. By executing such code conversion, for example, the frequency of occurrence of one of the binary values of phase modulation and the frequency of the carrier wave can be adjusted, so that the degree of freedom in designing the optical disk medium 12 can be improved.

【0041】

Further, in the above embodiment, it is illustrated that one bit of the address information corresponds to two cycles of the wobble signal, but this may correspond to an integer cycle, and for example, it can correspond to one cycle or four cycles. Is.

【0042】

Here, a cutting device (not shown), which is an optical disk device that forms a groove wobbled as described above on an optical disk master, will be briefly described below with reference to FIG. 7. Like the disk drive 13 described above, this cutting device has a rotation drive mechanism, an optical head, a rotation control circuit, a head control circuit, and the like, and also has a phase modulator 31.

【0043】

The rotation drive mechanism rotationally drives the optical disc master, and the optical head forms a groove on the rotating optical disc master. The rotation control circuit controls the rotation speed of the rotation drive mechanism in response to the address information of the groove, and keeps the relative speed between the optical head and the optical disk master constant. The phase modulator 31 phase-modulates the address information of the groove to generate a wobble signal, and the head control circuit reciprocates the scanning position of the optical head in the radial direction of the optical disc master in response to the wobble signal.

【0044】

In such a configuration, the cutting device described above forms a groove wobbled corresponding to the address information on the optical disc master. In that case, a wobbled groove is formed corresponding to the wobble signal whose address information is phase-modulated. Therefore, for example, a disk stamper may be manufactured from this optical disk master to mass-produce the above-mentioned optical disk medium 12. it can.

【0045】

In the optical disc medium 12 of the present embodiment, the duty ratio of the wobble signal does not change with respect to the binary value of the address information. Therefore, the cutting device forming the groove on the optical disc master as described above converts the address information into a predetermined code. It can be directly converted into a wobble signal without any processing, and the burden of this processing is small and the speed is high.

【0046】

A second embodiment of the present invention will be described below with reference to FIGS. 8 and 9. Regarding the present embodiment, detailed description of the same parts as those of the first embodiment described above will be omitted by using the same names and reference numerals.

【0047】

Similar to the optical disk system 11 described above, the optical disk system of the present embodiment also includes an optical disk medium and a disk drive which is an optical disk device, and the groove which is a track of the optical disk medium also supports a wobble signal whose address information is phase-modulated. And wobbling.

【0048】

However, the binary value of the address information and the phase of the wobble signal do not have a one-to-one correspondence, and as shown in FIG. 8, the binary value of the address information and the presence or absence of phase inversion of the wobble signal are one-to-one. It corresponds. That is, the phase of the wobble signal is inverted only in response to the occurrence of "1", which is one of the two values of the address information, and the phase of the wobble signal is inverted even if "0" of the address information is generated. Not done.

【0049】

The main structure of a disk drive that records and reproduces information on such an optical disk medium is the same as that of the disk drive 13 described above. However, as shown in FIG. 9, in the regenerative circuit 41, the output of the bandpass filter 5 is branched into two, and the delay circuit 42 is inserted in one of them. These two wires are connected to one product circuit 43, and the low-pass filter 44 is connected to the product circuit 43.

【0050】

The bandpass filter 5 extracts a wobble signal of a specific frequency band from the tracking signal, and the delay circuit 42 delays the wobble signal by a time corresponding to one bit of address information, as shown in FIG. The product circuit 43 superimposes the delay signal on the undelayed wobble signal, and the low-pass filter 44 smoothes the product signal and restores the address information. Since the output signal of the low-pass filter 44 is not exactly the restored address information as a digital signal, it is actually preferable to post-process it with a monostable multivibrator or the like.

【0051】

In such a configuration, the optical disk system of the present embodiment can also record and reproduce information on the optical disk medium by the disk drive, similarly to the optical disk system 11 described above.

【0052】

At this time, the address reproduction circuit 41 of the disk drive extracts a wobble signal of a specific frequency band from the tracking signal detected from the optical disk medium by the bandpass filter 5, divides the wobble signal into two, and divides one of them into two. Delay circuit 42 Delays by the time corresponding to 1 bit of address information. Then, the delayed wobble signal and the undelayed wobble signal are multiplied by the product circuit 43, and the product signal is smoothed by the low-pass filter 44 to restore the address information.

【0053】

Similarly to the optical disk system 11 described above, the optical disk system of the present embodiment also supports the wobble signal in which the groove wobbling of the optical disk medium is phase-modulated with the address information. Therefore, the C / N required for reproducing the address information. It is possible to shorten the amplitude of the wobbling of the groove while ensuring the above, and it is possible to increase the density of the arrangement pitch of the groove and expand the recording capacity.

【0054】

In particular, since the optical disk medium of the present embodiment has a one-to-one correspondence between the generation of one of the binary values of the address information and the phase inversion of the wobble signal, the disk drive has an address reproduction circuit 41 having a simple structure. Address information can be played back at high speed by simple processing. Moreover, since the phase inversion of the wobble signal corresponds only to the occurrence of "1", which is one of the binary values of the address information, for example, the frequency of occurrence of "0" is high and the frequency of occurrence of "1" is low in the address information. In this case, the frequency of inverting the phase of the wobble signal is also reduced. That is, since the wobbling shape of the groove is simple, the formation of this groove becomes easy.

【0055】

The cutting device, which is an optical disk device that forms the groove wobbled in this way on the optical disk master, may invert the phase of the wobble signal in response to the generation of a predetermined binary value of the address information.

【0056】

[Effect of the invention]

In the optical disk medium of the invention according to claim 1, since the track is wobbled corresponding to the wobble signal whose address information is phase-modulated, the address information is satisfactorily restored even if the wobbling amplitude of the track is shortened. Therefore, it is possible to increase the recording capacity of the optical disk medium by increasing the arrangement pitch of the tracks.

【0057】

In the optical disk medium of the invention according to claim 2, since the address information is converted into a predetermined code and then phase-modulated, this code conversion adjusts the frequency of occurrence of one of the binary values of phase modulation and the frequency of the carrier wave. , It is possible to improve the degree of freedom in the design and specifications of the optical disk medium.

【0058】

In the optical disk medium of the invention according to claim 3, since one bit of the address information corresponds to the integer period of the wobble signal, the duty ratio of the wobble signal phase-modulated with the address information is constant, so that the address information is a wobble signal. It is possible to convert directly to.

【0059】

In the optical disk medium of the invention according to claim 4, since the binary value of the address information corresponds to the phase of "0" degree and "180" degree of the wobble signal, the phase of the wobble signal determines the track. Can be formed into an uninterrupted shape.

【0060】

In the optical disk medium of the invention according to claim 5, since the binary value of the address information and the phase of the wobble signal have a one-to-one correspondence, the binary value of the address information can be detected by detecting the phase of the wobble signal. Therefore, when recording information on an optical disc medium, the address information can be restored at high speed with a simple circuit.

【0061】

In the optical disc medium of the invention according to claim 6, since the binary value of the address information and the presence / absence of the phase inversion of the wobble signal have a one-to-one correspondence, the address can be determined if the presence / absence of the phase inversion of the wobble signal is determined. Since the binary value of the information can be detected, the address information can be restored at high speed with a simple circuit when recording the information on the optical disc medium or the like.

【0062】

In the optical disc medium of the invention according to claim 7, if the phase of the wobble signal is inverted in response to the occurrence of one of the binary values of the address information, the presence or absence of the phase inversion of the wobble signal can be determined. Since the binary value of the address information can be detected, the address information can be restored at high speed with a simple circuit when recording the information on the optical disc medium or the like.

【0063】

In the optical disk medium of the invention according to claim 8, since the carrier frequency of the phase modulation of the address information is located between the tracking servo band and the RF signal band, the wobble signal, the tracking error signal, and the RF signal are reproduced at the time of reproduction. Since they do not interfere with each other, each signal can be reproduced with good characteristics when recording information on an optical disk medium or the like.

【0064】

The optical disk device of the invention according to claim 9 has a rotation drive mechanism for rotationally driving an optical disk medium in which a track is wobbled in response to address information, and an optical scan of the track of the rotating optical disk medium to detect at least a tracking signal. By having an optical head, a bandpass filter that extracts a wobble signal of a specific frequency band from a tracking signal, and a phase detector that detects the phase of the wobble signal and restores the address information, the track of the optical disk medium is addressed. The wobble signal is extracted from the tracking signal of this optical disk medium even when the information is wobbled corresponding to the phase-modulated wobble signal and the binary value of the address information and the phase of the wobble signal have a one-to-one correspondence. And the address information can be restored.

【0065】

The optical disk device of the invention according to claim 10 has a rotation drive mechanism for rotationally driving an optical disk medium in which a track is wobbled in response to address information, and an optical scan of the track of the rotating optical disk medium to detect at least a tracking signal. An optical head, a bandpass filter that extracts a wobble signal of a specific frequency band from a tracking signal, a delay circuit that delays the wobble signal by the time corresponding to one bit of address information, and a wobble signal that does not delay the delay signal. By having a product circuit to be loaded on the product and a low-pass filter that smoothes the product signal and restores the address information, the track of the optical disk medium is wobbled corresponding to the wobble signal whose address information is phase-modulated. Even when the binary value of the address information and the presence / absence of phase inversion of the wobble signal have a one-to-one correspondence, the wobble signal can be extracted from the tracking signal of the optical disk medium to restore the address information.

【0066】

The optical disk device of the invention according to claim 11 has a rotation drive mechanism that rotationally drives the optical disk master, an optical head that optically scans the rotating optical disk master to form a track, and a relative speed between the optical head and the optical disk master. A rotation control circuit that controls the rotation speed of the rotation drive mechanism according to the address information of the track so that it becomes constant, a phase modulator that phase-modulates the address information of the track of the optical disc master to generate a wobble signal, and this wobble. By having a head control circuit that reciprocates the scanning position of the optical head in the radial direction of the optical disc master in response to the signal, a wobbled track corresponding to the wobble signal in which the address information is phase-modulated is formed on the optical disc master. can do.

【0067】

In the invention of claim 12, the phase modulation means inverts the phase of the wobble signal and the phase of the wobble signal by inverting the phase of the wobble signal in response to the occurrence of one of the binary values of the address information. It is possible to form a wobbling track on the optical disk master in a state where there is a one-to-one correspondence between the presence and absence of.

[Simple explanation of drawings]

[Figure 1]

It is a time chart which shows the relationship between the address information of the optical disk medium of the 1st Embodiment of this invention, a theoretical wobble signal, and an actual wobble signal.

[Figure 2]

It is a schematic diagram which shows the disk drive which is the optical disk apparatus of 1st Embodiment of this invention.

[Fig. 3]

It is a block diagram which shows the address reproduction circuit of a disk drive.

[Fig. 4]

It is a characteristic diagram which shows various modulation methods.

[Fig. 5]

As a first modification, it is a time chart showing the relationship between the address information, the biphase code which is a predetermined code, and the wobble signal.

[Fig. 6]

As a second modification, it is a time chart showing the relationship between the address information, the Manchester code which is a predetermined code, and the wobble signal.

[Fig. 7]

It is a block diagram which shows the phase modulator which is the phase modulation means of the cutting apparatus which is an optical disk apparatus.

[Fig. 8]

It is a time chart which shows the relationship between the address information of the optical disk medium of the 2nd embodiment of the present invention, a wobble signal, a delay signal, a product signal, a filter output, and a restoration result.

[Fig. 9]

It is a block diagram which shows the address reproduction circuit of the disk drive which is the optical disk apparatus of the 2nd Embodiment of this invention.

[Fig. 10]

It is a schematic diagram which shows the shape of the land and the groove of the optical disk medium of one conventional example.

[Fig. 11]

It is a time chart which shows the relationship between the address information of an optical disk medium, a biphase code, and a wobble signal.

[Fig. 12]

It is a block diagram which shows the address reproduction circuit of the disk drive which is an optical disk apparatus of one conventional example.

[Explanation of symbols]

2 trucks 5 bandpass filter 12 Optical disc medium 13 Optical disc device 14 Rotation drive mechanism 15 Optical head 22 Phase detector 31 phase modulator 42 Delay circuit 43 Multiplication circuit 44 Lowpass filter