JP3356219B2 - Information recording / reproducing method for disk medium, information reproducing apparatus for disk medium, and information reproducing method for disk medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recording and reproducing information on and from a disk medium such as an optical disk and a magneto-optical disk, and a method for recording and reproducing information on the disk medium.
The present invention relates to a body information reproducing apparatus and a method of reproducing information from a disk medium .

[0002]

2. Description of the Related Art "Optical Disc Technology" Onoe, Murayama, Koide, Yamada, Kunikane, February 22, 1989, Radio Technology Company, No. 222-2.
On page 33, as an optical disk format, a CLV (Constant Linear Velocity) is used to control the spindle motor for rotating the optical disk so that the linear velocity of an information track to be recorded and reproduced becomes constant anywhere on the optical disk.
city) method, CAV (Constant Angular Velocity) method in which the spindle motor rotates at a constant speed, and MCLV (Modified) that simplifies the shift control of the spindle motor.
A CLV) system and an MCAV (Modified CAV) system in which the recording frequency is increased stepwise toward the outside of the optical disk are described. Among these types of disk media, CAV type disk media have been put to practical use as optical video disks and audio compact disks, and are currently most widely used because they are easy to manufacture and have the largest recording capacity. The MCAV disk medium is divided into a plurality of areas in the radial direction, and the recording / reproducing frequency is switched to a different frequency for each area.

In Japanese Patent Application Laid-Open No. 58-17547, a digitally encoded signal of information such as video is recorded concentrically or spirally on a disk-shaped recording medium rotating at a constant angular velocity by a laser beam or the like. In the recording apparatus, a recording area extending in a radial direction of the disc-shaped recording medium is divided into a plurality of pieces, and a recording information amount per unit time to be recorded in each of the recording areas is set to a recording area distant from the center of the disc-shaped recording medium. The optical information recording device is characterized in that it is switched and changed stepwise so as to increase as it becomes.

Japanese Patent Application Laid-Open No. Sho 60-177404 discloses a detecting means for detecting an access position of a disk having a spiral or concentric track in a disk device for recording or reproducing data. Control means for controlling the recording or reproduction timing of data in accordance with the detection result by the detection means; and recording or reproduction in accordance with the control means while rotating the disc at a constant speed during data recording or reproduction. Alternatively, there is described a disk device having recording and reproducing means for performing reproduction.

[0005]

When information is recorded / reproduced on / from a CLV type disk medium, the number of revolutions of the spindle motor is varied depending on the inner and outer circumferential positions of the information track for recording / reproducing information on the disk medium. Therefore, the control of the spindle motor at the time of random access for randomly accessing the information tracks on the disk medium becomes complicated, and the amount of heat generated by the spindle motor increases. Of course, even in the case of a CLV-type disk medium, its usefulness in the field of recording and reproducing moving images and audio sequentially on the disk medium at a constant data transfer rate for applications in which random access is hardly necessary is inevitable.

On the other hand, the MCAV disk medium is divided into a plurality of areas in the radial direction and the recording / reproducing frequency is switched to a different frequency for each area. Recording and reproduction cannot be performed, and various combinations of recording and reproduction frequencies occur depending on the number of area divisions, which has a disadvantage that compatibility of information recording and reproduction of a disk medium is lost.

According to the present invention, compatibility with information recording / reproduction on a CLV type disk medium can be ensured, data transfer speed can be increased, and continuous operation can be performed without increasing power consumption or heat generation even during random access operation. method of recording and reproducing information to a disk medium capable of performing information recording and reproduction, and to provide information reproducing method of an information reproducing apparatus and the disk medium of the disk <br/> medium body.

[0008]

In order to achieve the above object, the invention according to claim 1 provides an information recording area in which an information signal is recorded in advance at a constant linear recording density along an information track having a constant pitch. Spins the disc medium at a constant speed and reproduces information signals from the information tracks
And, before being recorded in advance along the information track
Based on the address information data indicating the position of the information track.
A clock having a center frequency is selectively generated, an information signal is reproduced from the information track and binarized, and a bit synchronization signal is reproduced based on a phase comparison between the information signal and the generated clock. The content of the information signal is reproduced using the signal, or a new information signal is recorded on an unrecorded information track on the disk medium .

According to a second aspect of the present invention, in the information recording / reproducing method for a disk medium according to the first aspect, the means for reproducing the bit synchronization signal based on the information signal has a bit synchronization pull-in frequency range that exceeds each other. using a PLL circuit having a large number of frequency generator to wrap, changing cut the number of frequency generator in response to the recording and reproducing position of the inner and outer peripheral direction on the disk medium.

According to a third aspect of the present invention, in the information recording / reproducing method for a disk medium according to the second aspect, the plurality of frequency generators are selected as a clock used when recording new data. of generating a clock of a frequency corresponding to the recording and reproducing position of the inner and outer peripheral direction of the upper
Let

The invention described in claim 4 is the invention according to claim 2 or 3.
In the method for recording / reproducing information on / from a disk medium described above, a number of output frequencies of the PLL circuit are set to frequencies close to each other within ± 1% .

According to a fifth aspect of the present invention, the pitch is constant.
Information at a constant linear recording density along the
A disk medium having an information recording area in which a signal is recorded
A spindle motor for rotating at a constant rotational speed;
An optical head for reproducing an information signal from an information track;
The information track previously recorded along the information track
Center based on the address information data indicating the location of the
Multiple clock generators that selectively generate clocks of frequency
And an information signal reproduced from the information track and binarized.
And the clock generated by the multiple clock generator.
A phase comparison circuit for performing a phase comparison.
Of bit synchronization signal based on phase comparison result
And reproduces the contents of the information signal using this bit synchronization signal.
Is what you do.

[0013] The invention according to claim 6 provides the data according to claim 5.
In a disc medium information reproducing apparatus, based on an information signal,
As a means of reproducing the bit synchronization signal by
Many overlapping frequency ranges overlap each other
Using a PLL circuit having a frequency generator of
Corresponding to the reproduction position in the inner and outer peripheral directions on the recording medium.
This is for switching the frequency generator .

[0014] The invention according to claim 7 is the data according to claim 6.
New data is recorded on the disc media information reproducing device.
The clock used when recording
Select a generator and replay in the inner and outer directions on the disk medium.
A clock having a frequency corresponding to the raw position is generated .

The invention according to claim 8 is the invention according to claim 6 or 7.
In the information reproducing apparatus of the disk medium body, wherein the PL
A number of output frequencies of the L circuit are set to close frequencies within ± 1%.

According to a ninth aspect of the present invention, there is provided an information processing apparatus having a constant pitch.
Information at a constant linear recording density along the
A disk medium having an information recording area in which a signal is recorded
It rotates at a certain number of revolutions and the information signal from the information track
Play back and record in advance along the information track
Of address information indicating the position of the information track
And selectively generates a clock having a center frequency based on the
The information signal is reproduced from the information track and binarized, and this information is read.
Based on the phase comparison between the report signal and the generated clock.
Regenerate the bit synchronization signal and use this bit synchronization signal
Reproduce the contents of the information signal.

[0017]

[Action] In the first aspect of the present invention, a disk medium having an information recording area in advance information signal is recorded at a constant linear recording density along the pitch constant information track is rotated at a constant rotational speed, said Information signal from information track
Played and pre-recorded along the information track
Of address information indicating the position of the information track
A clock having a center frequency is selectively generated based on the data track, an information signal is reproduced from the information track and binarized,
A bit synchronization signal is reproduced based on a phase comparison between the information signal and the generated clock, and the content of the information signal is reproduced or a new information signal is recorded on the unrecorded information track on the disk medium by using the bit synchronization signal. Or recorded in

According to a second aspect of the present invention, in the information recording / reproducing method for a disk medium according to the first aspect, the means for reproducing the bit synchronization signal based on the information signal is such that the bit synchronization pull-in frequency ranges exceed each other. A PLL circuit having a number of frequency generators to be wrapped is used, and the number of the frequency generators is switched according to the recording / reproducing position in the inner and outer peripheral directions on the disk medium.

According to a third aspect of the present invention, in the information recording / reproducing method for a disk medium according to the second aspect, the plurality of frequency generators are selected as clocks used when recording new data. A clock having a frequency corresponding to the upper and lower recording / reproducing positions in the inner and outer peripheral directions is generated.

According to a fourth aspect of the present invention, in the method for recording and reproducing information on a disk medium according to the second or third aspect,
Many output frequencies of the PLL circuit are close frequencies within ± 1%.

According to the fifth aspect of the present invention, the pitch is constant.
Information is recorded at a constant linear recording density along the information track.
Disc medium having an information recording area on which an information signal is recorded
Is rotated at a constant speed by a spindle motor,
A head reproduces an information signal from the information track. Many
A few clock generators
Address information indicating the position of the information track recorded
Selects and generates a clock with a center frequency based on the report data
I do. Binary information reproduced from the information track
Signal and the clock generated by the multiple clock generator.
The phase comparison is performed by a phase comparison circuit. Said position
Bit synchronization signal based on the phase comparison result by the phase comparison circuit
The signal is reproduced, and the information signal is
The content is played.

In the invention according to claim 6, the invention according to claim 5 is provided.
In an information reproducing apparatus for a disk medium, based on an information signal,
As a means for reproducing bit synchronization signals, bit synchronization
Many of the pull-in frequency ranges overlap each other.
A PLL circuit having a number of frequency generators is used,
According to the playback position in the inner and outer peripheral directions on the disk medium,
A number of frequency generators are switched.

[0023] In the present invention of claim 7, wherein, according to claim 6, wherein
In the information reproducing device of the disk medium, new data is
As the clock used for recording, the multiple frequencies
A number of generators are selected in the inner and outer directions on the disk medium
A clock having a frequency corresponding to the reproduction position is generated.

[0024] In the invention of claim 8, the information reproducing apparatus of the disk medium of claim 6 or 7, wherein P
Many output frequencies of the LL circuit are close frequencies within ± 1%.

According to the ninth aspect, the pitch is constant.
Information is recorded at a constant linear recording density along the information track.
Disc medium having an information recording area on which an information signal is recorded
Rotates at a certain number of revolutions,
No. is reproduced and recorded in advance along the information track.
Of the address information indicating the position of the recorded information track.
A center frequency clock is selectively generated based on the data.
And an information signal is reproduced from the information track and binarized.
And the phase ratio between the information signal and the generated clock.
The bit synchronization signal is reproduced based on the comparison
The content of the information signal is reproduced using the period signal.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention has the following features. A disk medium composed of a CLV optical disk is rotated at a constant frequency.

The reproducing speed and the recording speed (clock frequency) are changed in accordance with the positions of the information tracks on the optical disk in the inner and outer peripheral directions (radial direction) in accordance with the information already recorded on the information tracks. FIG. 2 is a schematic diagram showing a CLV optical disk. In the CLV optical disc 1, information tracks are spirally or concentrically arranged at a fixed pitch between an innermost track 2 and an outermost track 3. This CLV optical disk 1 is inserted into its center hole 4
, The clock frequency increases in direct proportion to the radius of the information track. Therefore, the clock frequency may be changed continuously. However, if the clock frequency is changed in steps of 1% or less as described below, an effect similar to that obtained when the clock frequency is changed substantially continuously can be obtained.

Information track radius Clock center frequency R ₀ (radius of innermost information track) f ₀ R ₀ (1 + 0.005) f ₀ (1 + 0.005) R ₀ (1 + 0.010) f ₀ (1 + 0. 010) R ₀ (1 + 0.015) f ₀ (1 + 0.015) ・ ・ ・ ・ ・ ・ ・ R ₀ (1 + 0.995) f ₀ (1 + 0.995) R ₀ (1 + 1) f ₀ (1 + 1) Bit synchronization between the signal and the clock can be achieved by a PLL (Phase Lock Loop) circuit, and the clock frequency can be set within ± 1% of the ideal value during data recording. Synchronization is fully possible.

FIG. 1 shows a circuit configuration of an information recording / reproducing apparatus including an optical disk device used in the present embodiment. In this optical disc apparatus, the CLV optical disc 1 has an information recording area in which information signals such as address information are recorded in advance at a constant linear recording density along an information track. Is driven to rotate at a constant rotation speed by a spindle motor.

At the time of data recording, the optical head 5 records an information signal from the innermost track 2 to the outermost track 3 on the optical disc 1. In this case, the recording control circuit 6 causes the optical head 5 to record a new information signal on the optical disk 1 in synchronization with the clock from the multiple clock generator 7 and bit synchronization. Therefore, on the optical disc 1, a new information signal is recorded at a constant linear density on an unrecorded information track by the optical head 5, and its recording frequency is controlled by a large number of clock generators 7.
Clock frequency.

As the multiple clock generator 7, a number of frequency generators whose center frequency is set to a frequency corresponding to the radius of each information track on the optical disk 1 are used.
The plurality of frequency generators are selectively switched to a clock output state in accordance with the position information from the optical head 5 and the address information from the controller 8 corresponding to the information track on which information on the optical disk 1 is to be recorded, thereby recording a clock. By outputting the recording frequency to the control circuit 6, the recording frequency is adjusted to the radius of each of a large number of information tracks arranged at a constant pitch between the innermost track 2 and the outermost track 3 on the optical disc 1 as described above. Correspondingly changes in steps within 1%.

The optical head 5 reproduces an information signal from the optical disk 1, and this reproduced signal is converted into a binary signal by a binarizing circuit 9.
Valued. The PLL circuit 10 includes a phase comparison circuit 11 and a multi-clock generator 7, and reproduces a bit synchronization signal composed of a clock from the binarized signal from the binarization circuit 9. That is, the phase comparison circuit 11 compares the phase of the clock from the multiple clock generator 7 (the clock from the frequency generator in the clock output state) with the binary signal from the binarization circuit 9 and determines the phase difference. The phase difference signal is output to the multiple clock generator 7, and the frequency generator in the clock output state of the multiple clock generator 7 is controlled by the phase difference signal from the phase comparison circuit 11 to control the transmission frequency to 2.
A clock synchronized with the binarized signal from the digitizing circuit 9 is generated. Since the clock frequency of the reproduced signal from the binarization circuit 9 changes continuously, in order to cover the change in the clock frequency, the PLL circuit 10 uses the multiple clock generators 7.
The frequency generators of which the pull-in frequency ranges of the bit synchronization for the reproduced signal overlap each other are used.

The data separator 12 reproduces data from the binarized signal from the binarizing circuit 9 by the clock from the PLL circuit 10. Since the optical disc 1 has an information recording area in which information signals such as address information are recorded in advance along information tracks, the data separator 12 reproduces data such as address information. The controller 8 outputs to the clock generator 7 address information indicating the position of the information track in the reproduction data from the data separator 12.

Also, position information indicating the position is output from the optical head 5 to the multiple clock generator 7, and the position information from the optical head 5 and the address information from the controller 8 are information on which information on the optical disc 1 is to be recorded. It indicates the position of the track, and each frequency of the multiple clock generator 7
The number generator is selectively switched to a clock output state in accordance with the information track on the optical disc 1 on which information is to be recorded, based on the position information from the optical head 5 and the address information from the controller 8.

During data reproduction, when the CLV optical disk 1 is driven to rotate at a constant rotational speed by a spindle motor around its center hole 4, the linear velocity continuously increases in direct proportion to the radius of the information track. Be faster. The optical head 5 reproduces an information signal from the optical disk 1, and the reproduced signal is binarized by a binarization circuit 9. The PLL circuit 10 reproduces a clock from the binarized signal from the binarization circuit 9 as described above, and the data separator 12 converts data from the binarized signal from the binarization circuit 9 with the clock from the PLL circuit 10. Reproduce.

The controller 8 outputs a large number of address information indicating the position of the information track among the reproduced data from the data separator 12 to the clock generator 7. Also, position information indicating the position is output from the optical head 5 to the multiple clock generator 7 , and the frequency information of the multiple clock generator 7 is generated.
The livestock is composed of the position information from the optical head 5 and the controller 8.
The information on the optical disc 1 is selectively switched to the clock output state in accordance with the information track on which the information on the optical disc 1 is to be reproduced by the address information from the CPU.

In this embodiment, since the optical disk 1 is not divided into a plurality of regions as in the case of the MCAV optical disk, the PLL circuit 10 having a variety of center frequencies according to the number of divided regions is prepared. It is not necessary to do so, and the apparatus can be simplified. Further, the PLL circuit 10 uses the frequency generators of the multiple clock generators 7 whose frequency ranges of the bit synchronization pull-in for the reproduced signal overlap each other, so that the bit synchronization pull-in is performed at all positions of the CLV optical disk 1. Enabled recording and reproduction of information.

Further, since the clock frequency is not continuously changed at the time of data recording but is changed corresponding to each radius of a large number of information tracks on the optical disk 1, bit synchronization at the time of data reproduction can be easily performed. it can. Moreover,
Since the clock frequency is switched in steps of ± 1% during data recording, pull-in of the PLL circuit 10 can be performed without any trouble during data reproduction.

Since the controller 8 recognizes the position of the information track from the reproduced signal and sets the recording frequency based on the information, the recording frequency can be set reliably. Further, compatibility with information recording / reproducing on the optical disk 1 of the CLV system can be ensured, and the data transfer speed can be increased. Even during the random access operation, there is no increase in power consumption or heat generation. Further, continuous information recording / reproducing can be performed, and the compatibility of information recording / reproducing of the optical disk is not impaired.

[0040]

As described above, according to the first aspect of the present invention, a disk medium having an information recording area in which an information signal is recorded in advance at a constant linear recording density along an information track having a constant pitch is fixed. At the number of rotations, the information
An information signal is reproduced from a track, and is reproduced along the information track .
Indicates the position of the information track recorded in advance.
A clock having a center frequency is selectively generated based on data of the address information, an information signal is reproduced from the information track to be binarized, and a bit synchronization signal is generated based on a phase comparison between the information signal and the generated clock. Since the information is reproduced and the content of the information signal is reproduced by using the bit synchronization signal or a new information signal is recorded on an unrecorded information track on the disk medium, it is compatible with information recording and reproduction on a CLV type disk medium. Therefore, the data transfer speed can be increased and the power consumption and the amount of heat generated do not increase during the random access operation. In addition, continuous information recording / reproduction can be performed, and the compatibility of information recording / reproduction on a disk medium is not impaired. Further, since the disk medium is not divided into a plurality of areas unlike the disk medium of the MCAV system, it is not necessary to prepare a PLL circuit having various kinds of center frequencies according to the number of divided areas. Can be simplified.

According to the second aspect of the present invention, in the information recording / reproducing method for the disk medium according to the first aspect, the means for reproducing the bit synchronization signal based on the information signal includes:
Using a PLL circuit having a number of frequency generators in which the range of the pull-in frequency of the bit synchronization overlaps with each other, and switching the number of the frequency generators corresponding to the recording / reproducing positions in the inner and outer peripheral directions on the disk medium, C
Bit-synchronous pull-in can be performed at all positions on the LV optical disk, and information can be recorded and reproduced.

According to a third aspect of the present invention, in the information recording / reproducing method for a disk medium according to the second aspect, the plurality of frequency generators are selected as clocks used when recording new data. Since a clock having a frequency corresponding to the recording / reproducing position in the inner and outer peripheral directions on the disk medium is generated, bit synchronization at the time of reproducing can be easily performed.

According to a fourth aspect of the present invention, in the information recording / reproducing method for a disk medium according to the second or third aspect, a number of output frequencies of the PLL circuit are set to be close to within ± 1%. Since the frequency is adjusted, the PLL circuit can be pulled in during reproduction without any trouble.

According to the invention described in claim 5, the pitch is one.
A certain linear recording density along a certain information track
Disc having an information recording area on which an information signal is recorded
A spindle motor for rotating the medium at a constant rotation speed,
An optical head for reproducing an information signal from the information track;
The information pre-recorded along the information track
Based on the address information data indicating the position of the
Multiple clocks to select and generate clocks with center frequency
Greige and binarized information reproduced from the information track
Signals and clocks generated by the multiple clock generator
A phase comparison circuit for performing a phase comparison with the phase ratio
Bit synchronization signal based on the phase comparison result
And reproduce the information signal using this bit synchronization signal.
Since the information is reproduced, the information can be reproduced on the CLV system disk medium.
Data transfer speed,
Increase in power consumption and heat generation even during dam access operation
Is not accompanied. Moreover, continuous information reproduction can be performed.
The data playback compatibility of the disk media
No. In addition, discs such as MCAV disc media
Since the disk media is not divided into multiple areas,
PLL times with various kinds of center frequencies according to the number of divisions
There is no need to prepare a route, and the equipment must be simplified.
Can be.

According to the invention of claim 6, according to claim 5,
In the information reproduction device of the disk medium on which
As a means for reproducing a bit synchronization signal based on
Synchronization pull-in frequency ranges overlap each other
Using a PLL circuit having a number of frequency generators,
According to the playback position in the inner and outer peripheral directions on the disk medium,
Since a number of frequency generators are switched , the CLV optical
Bit synchronization can be pulled in at all positions on the disk.
Thus, information can be reproduced.

According to the invention of claim 7, according to claim 6,
New data in the disc player
The clock used to record the data
Select the frequency generator and select the inner and outer
Since a clock having a frequency corresponding to the reproduction position is generated , the bit synchronization at the time of reproduction can be easily performed.

According to the invention described in claim 8, according to claim 6 or
In the information reproducing apparatus of the disk media of other 7, since the number of output frequency within ± 1% of the sinusoidal frequencies of the PLL circuit, can be performed without any trouble retraction of the PLL circuit at the time of reproduction.

According to the ninth aspect, the pitch is one.
A certain linear recording density along a certain information track
Disc having an information recording area on which an information signal is recorded
The medium is rotated at a constant speed, and information is read from the information track.
Reproduce the information signal and advance along the information track
Address information indicating the position of the recorded information track
Selects and generates center frequency clock based on data
Reproducing the information signal from the information track and binarizing it.
And a phase comparison between the information signal and the generated clock.
The bit synchronization signal is reproduced based on the
Since the content of the information signal is reproduced using the signal , the CLV method
Data compatibility can be ensured with information reproduction on disk media.
Data transfer speed, and erase even during random access operation.
There is no increase in power consumption or heat generation. Moreover, continuous
Information can be reproduced efficiently, and the information
There is no loss of raw compatibility. Furthermore, MCAV system
Disk media into multiple areas like
Since it is not divided, there are many types of
There is no need to prepare a PLL circuit with a center frequency.
Therefore, the device can be simplified.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration of an information recording / reproducing apparatus used in one embodiment of the present invention.

FIG. 2 is a schematic diagram showing a CLV optical disk.

[Explanation of symbols]

 Reference Signs List 5 optical head 6 recording control circuit 7 multiple clock generator 8 controller 9 binarization circuit 10 PLL circuit 11 phase comparison circuit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B 20/10-20/14 G11B 19/28 G11B 7/005

Claims (9)

(57) [Claims] 1. A disk medium having an information recording area in which an information signal is recorded in advance at a constant linear recording density along an information track having a constant pitch is rotated at a constant rotation speed.
An information signal is reproduced from the information track, and an information signal of the information track recorded in advance along the information track is read .
A clock having a center frequency is selectively generated based on data of address information indicating a position, an information signal is reproduced from the information track to be binarized, and bit synchronization is performed based on a phase comparison between the information signal and the generated clock. Reproducing a signal and using the bit synchronization signal to reproduce the content of the information signal or recording a new information signal on an unrecorded information track on the disk medium. How . 2. A method for recording / reproducing information on / from a disk medium according to claim 1, wherein the means for reproducing the bit synchronization signal based on the information signal includes generating a plurality of frequencies whose bit synchronization pull-in frequency ranges overlap each other. A method of recording and reproducing information on a disk medium, wherein the plurality of frequency generators are switched in accordance with recording and reproduction positions in the inner and outer peripheral directions on the disk medium using a PLL circuit having a device. 3. A method for recording / reproducing information on / from a disk medium according to claim 2, wherein said plurality of frequency generators are selected as clocks used for recording new data in a direction toward the inner and outer circumferences on said disk medium. An information recording / reproducing method for a disk medium, wherein a clock having a frequency corresponding to a recording / reproducing position is generated. 4. A method for recording / reproducing information on a disk medium according to claim 2, wherein a large number of output frequencies of said PLL circuit are set to frequencies close to ± 1%. Information recording and playback method . 5. A constant pitch along a constant information track.
Information recording in which information signals are recorded in advance at a linear recording density of
A disk medium with a recording area
And Luz pin dollars motor, information signal from said information track
An optical head for reproducing information along the information track.
An address indicating the position of the information track previously recorded
Selects clock of center frequency based on data of source information
A multiple clock generator to generate and from the information track
Reproduced and binarized information signal and multiple clock generator
Phase comparison circuit that compares the phase with the clock generated by
And a path based on the phase comparison result by the phase comparison circuit.
The bit synchronization signal is reproduced based on the
And reproduces the content of the information signal using
Disc media information reproducing device . 6. An information reproducing apparatus for a disk medium according to claim 5,
Reproduces the bit synchronization signal based on the information signal
As a means to achieve this, the range of the pull-in frequency
Has multiple frequency generators overlapping each other
Using a PLL circuit, the inner and outer peripheral directions on the disk medium
Switching between the multiple frequency generators according to the playback position
An information reproducing apparatus for a disk medium. 7. An information reproducing apparatus for a disk medium according to claim 6.
Device to record new data.
As a check, the number of frequency generators is selected and the
Frequency corresponding to the playback position in the inner and outer circumference direction on the disk medium
Disk medium for generating clocks
Information reproducing device. In information <br/> report reproducing apparatus according to claim 8 according to claim 6 or 7 disk medium body according to characterized in that a number of the output frequency sinusoidal frequencies within 1% ± a of the PLL circuit information reproducing apparatus of the disk medium body. 9. A constant pitch along a constant information track.
Information recording in which information signals are recorded in advance at a linear recording density of
The disk medium having the recording area is rotated at a constant rotational speed,
An information signal is reproduced from the information track, and the information track is reproduced.
Of the information track pre-recorded along the
Center frequency based on address information data indicating position
Of the information track from the information track.
The information signal is reproduced and binarized .
Recovers bit synchronization signal based on phase comparison with lock
And reproduces the contents of the information signal using this bit synchronization signal.
A method for reproducing information from a disk medium .