JPH06150534A - Disk reproducing device - Google Patents

Abstract

PURPOSE:To reproduce a disk recorded by a CLV system by an MCLV system and to realize high speed access. CONSTITUTION:A compact disk 1 is divided to several zones, and the data are reproduced by rotating the disk 1 at a fixed rotational speed at every zone. At this time, when the data spreading over the zones and the access is spread over the zones regardless of the access in a vicinity, the zone is spread. Then, the reproduced data is outputted to the outside from a digital signal processing circuit 7. Thus, the disk recorded by the CLV system is reproduced by the MCLV system, and the high speed access is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc reproducing apparatus for reproducing data from a signal recorded on a disc-shaped recording medium.

[0002]

2. Description of the Related Art A compact disc reproducing device is shown as an example of a conventional disc reproducing device.

FIG. 3 is a block diagram showing a conventional disc reproducing apparatus, and FIG. 4 is a block diagram showing the digital signal processing circuit of FIG.

In FIG. 3, reference numeral 1 is a compact disc as a record carrier. This compact disc 1
Data is recorded by CLV (constant linear velocity) method,
It is rotated by the spindle motor 3 so as to have a constant linear velocity. An optical pickup 2 takes out data recorded on the disc as an analog reproduction signal.

Reference numeral 5 denotes a waveform shaping circuit, which shapes the analog reproduction signal output from the optical pickup 2 into a binary signal. The binarized data thus obtained is output to the digital signal processing circuit 9.

As shown in FIG. 4, the digital signal processing circuit 9 includes a synchronization detection circuit 41, a PLL circuit 42, a demodulation circuit 43, a crystal oscillation circuit 44, and a sub-coding detection circuit 4.
5, RAM (Random Access Memory) 46.

In FIG. 4, a synchronization detection circuit 41 detects frame synchronization from the binarized data output from the waveform shaping circuit 5.

PLL (Phase Locked Loop) circuit 42
Regenerates the clock from the binarized data.

The demodulation circuit 43 takes in a digital signal from the synchronization detection circuit 41 and outputs a CIRC (Cross Interleave R) signal.
An error is detected and corrected by an eed-Solomon code), and digital audio data 21 or digital data 23 demodulated by a reproduction timing signal given from a crystal oscillator circuit 44 is output.

The sub-coding detection circuit 45 reproduces the disk address information 24 and the like for performing track positioning.

The RAM 46 functions as a buffer for CIRC deinterleaving and error correction.

Further, in FIG. 3, reference numeral 10 denotes a servo circuit, which has two kinds of clocks output from the digital signal processing circuit 9 (a reference clock output from the crystal oscillation circuit 44 and a reproduction clock output from the PLL circuit 42). Control is performed so that the rotation speed of the spindle motor 3 matches the reference clock. Further, the slide motor 4 and the optical pickup 2 are controlled based on the access control signal 25 output from the access control device 8.

The access control device 8 controls the slide motor 4 and the optical pickup 2 via the servo circuit 10 based on the disk address information 24 output from the digital signal processing circuit 9 to perform track position determination.

Reference numeral 12 is a D / A conversion circuit, which outputs digital audio data 2 output from the digital signal processing circuit 9.
1 is converted into an analog voice signal 22 and output.

[0015]

Generally, CLV (constant linear velocity) is used as a method for recording on a disk-shaped recording medium.
System, CAV (constant rotation speed) system, MCLV (constant rotation speed in zone) system, and the like. The CLV system used for CD can record more data than the CAV system, but has a problem that the rotation speed is different between the inner and outer circumferences of the disc because the linear velocity is constant. Therefore, it is necessary to control the rotation speed every time access is made, which hinders shortening of access time.

As a method of shortening the access time, CLV is used.
A method of reproducing a disc recorded by the CAV method by the CAV method can be considered. Since the rotation speed is kept constant, the rotation speed control becomes unnecessary and high-speed access can be realized. However, in general, the linear velocities of the inner and outer circumferences of the disc have a difference of twice or more, so that the reproduction speed of the data also changes more than twice. Therefore, there is a problem that it is difficult to configure a circuit such as a data reproducing system.

Then, next, a method of reproducing the disc recorded by the CLV method by the MCLV method can be considered. MC
Since the LV method changes the rotation speed for each zone, the difference in linear speed can be suppressed to a small value. However, this method has a drawback in that the data spanning the zones cannot be reproduced due to the change in the rotation speed. Also,
Even if the access is in the vicinity, there is a drawback that the access time becomes long due to the rotation speed control when it extends over the zone.

It is an object of the present invention to provide a disc reproducing apparatus capable of rotating a disc recorded by the CLV system by the MCLV system to reproduce data and therefore realizing high-speed access.

[0019]

In order to solve the above-mentioned problems, the present invention divides a disk recorded by the CLV system into several zones and changes the rotation speed for each zone, and a spindle motor A control device for controlling was provided. Then, when reproducing data that spans zones, and when spanning zones despite access in the vicinity, the zones are expanded.

[0020]

In the present invention, a disc recorded by the CLV system is reproduced by the MCLV system. At that time, when the data that spans the zone is played back, or when the zone is accessed by a nearby access, the zone is expanded.

Therefore, a disc recorded by the CLV system can be rotated by the MCLV system to reproduce all data, and a disc reproducing apparatus capable of high-speed access can be provided.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention, and FIG. 2 is a block diagram showing the digital signal processing circuit of FIG. In FIG. 1, 1 is a compact disc as a record carrier. This compact disc 1
Are divided into several zones, and the spindle motor 3 and the rotation speed control device 30 rotate each zone at a constant rotation speed.

Reference numeral 2 is an optical pickup, which takes out the data recorded on the disk as an analog reproduction signal.

An analog waveform shaping circuit 5 shapes the analog signal output from the optical pickup 2 into a binary signal. The binarized data obtained in this way is
It is output to the digital signal processing circuit 7.

The digital signal processing circuit 7 reproduces a clock from the binarized data obtained by the analog waveform shaping circuit 5, demodulates the digital data 20 and outputs it. Also, the disc address information 24 is output. The details of the digital signal processing circuit 7 will be described later.

The digital data 20 is output in synchronization with the clock reproduced from the compact disc 1. Compact disc 1 recorded by CLV system
Is reproduced at a constant rotation speed in the same zone, the transfer speed of the digital data 20 is different between the inner and outer circumferences in the zone. If the digital data 20 is voice data, it cannot be converted into an analog voice signal unless it has a predetermined transfer rate.
At 11, the transfer rate is adjusted to a predetermined value. In the buffer RAM 11, the digital data 2 having the normal transfer speed, that is, the transfer speed different from that in the case of reproducing by the CLV system is thus described.
0 is sent, which is temporarily stored and digital voice data 21 of a predetermined transfer speed is output to the D / A conversion circuit 12.

Reference numeral 13 is a RAM controller, which is a buffer R.
It controls the input / output timing and address of the AM 11. The RAM control device 13 has a built-in reference clock, and controls the buffer RAM 11 to output digital data voice 21 at a predetermined transfer rate.

The D / A conversion circuit 12 includes a buffer RAM 1
The digital audio data 20 output from the No. 1 is converted into an analog audio signal 22 and output.

In order to continuously output the analog audio signal 22, it is necessary to rotate the spindle motor 3 so that the transfer speed of the digital data 20 becomes equal to or higher than the speed at which the digital data 20 is reproduced by the CLV method.

The servo circuit 6 controls the slide motor 4 and the optical pickup 2 based on the access control signal 25 given from the access control device 8. Further, the rotation speed control signal 2 provided from the rotation speed control device 30
The rotation speed of the spindle motor 3 is controlled based on 7.

The access control device 8 controls the slide motor 4 and the optical pickup 2 via the servo circuit 6 based on the disk address information 24 given from the digital signal processing circuit 7 to perform track positioning.

The rotation speed control device 30 controls the rotation speed of the spindle motor 3 via the servo circuit 6 on the basis of the disk address information 24 given from the digital signal processing circuit 7, and the rotation speed suitable for each zone. To control. When the data is reproduced over the zone, the rotation speed of the spindle motor 3 is not changed and the rotation speed is maintained as it is. Further, even when the zone is crossed despite the access in the vicinity, the rotation speed of the spindle motor 3 is maintained as it is without changing. Thus, the rotation speed control device 30 has a function of appropriately expanding the zone based on the disk address information 24.

The details of the digital signal processing circuit 7 will be described below with reference to FIG. The digital signal processing circuit 7 includes a synchronization detection circuit 41, a PLL circuit 42, a demodulation circuit 43, a sub-coding detection circuit 45, and a RAM 46.

In FIG. 2, the synchronization detection circuit 41 detects frame synchronization from the input binarized data and outputs it to the demodulation circuit 43.

The PLL circuit 42 reproduces a clock from the input binarized data and outputs it to the demodulation circuit 43.

The demodulation circuit 43 takes in the digital signal from the synchronization detection circuit 41 and uses the RAM 46 to perform CIRC.
Deinterleaving and error detection and correction by CIRC are performed. Then, the demodulated digital data 20 is output. The digital data 20 is output in synchronization with the clock reproduced by the PLL circuit 42.

The sub-coding detection circuit 45 reproduces the disc address information 24 for performing track positioning.

FIGS. 5 and 6 show examples of zone division of the disc of the first embodiment and the rotational speed of the disc. In FIGS. 5 and 6, reference numeral 1 denotes a compact disc, which indicates that it rotates at a constant rotation speed in each zone.

FIG. 5A shows the zone and the disk rotation speed in the initial state. Depending on where the accessed zone is, the zone 1, zone 2 and zone 3 rotate at appropriate rotation speeds. FIG. 5B shows the operating zone and the disk rotation speed. At this time, the range of the constant rotation speed is widened, and it is shown that the rotation is performed at the constant rotation speed even if the range of the zone in the initial state is exceeded.

FIG. 6 illustrates the actual operation. As an example, FIG. 6A shows the zone and the disk rotation speed after accessing the zone 1, and FIG. 6B shows the zone and the disk rotation speed after accessing the zone 2. The zone 1 in FIG. 6A and the zone 2 in FIG. 6B spread in this way, and even when the data is reproduced over the adjacent zone in the initial state, the data can be continuously and continuously reproduced. . Also, if it is a nearby access,
The access time can be shortened because the access can be made without changing the rotation speed even when the zone is crossed.
In the vicinity of the zone, the change width of the data reproduction speed is small, so that it is not necessary to modify or change the data reproduction circuit such as the digital signal processing circuit.

With the above-mentioned structure, in this embodiment,
Data can be reproduced by rotating a disc recorded by the CLV method by the MCLV method. The MCLV system can increase the data transfer rate in the inner peripheral portion because it can set an appropriate rotation speed both in the inner peripheral portion and the outer peripheral portion of the disc. Also, it is possible to suppress an increase in the operating frequency of each circuit at the time of reproducing the outer periphery, which occurs when the disc is rotated at a constant rotation speed,
The load on the waveform shaping circuit, the signal processing circuit, etc. can be reduced. Further, by sequentially writing the reproduced data in the buffer RAM circuit and reading the written data at a constant transfer rate, it is possible to reproduce the sound even in the MCLV system.

FIG. 7 (a) shows an example of zone division of the disk of the second embodiment of the present invention and the rotational speed of the disk. In FIG. 7A, 1 is a compact disc, which indicates that it rotates at a constant rotation speed in each zone. In the first embodiment, even if the zone is expanded after the access and is reproduced over the adjacent zone, the data can be continuously reproduced without a break. However, it is necessary to continue the continuous reproduction as it is, and to change the rotation speed when exceeding the widened zone. In the second embodiment, when the zone thus widened is also exceeded, the rotational speed is gradually changed to match the rotational speed of the adjacent zone. Therefore, the data can be continuously reproduced during this period.

FIG. 7B illustrates the actual operation. FIG. 7B shows the zone and the disc rotation speed after the zone 2 is accessed. In FIG. 7B, the zone 2 spreads in this way, and even when the data is reproduced over the adjacent zone in the initial state, the data can be continuously reproduced. Then, even when the data is continuously reproduced and exceeds the widened zone, the data can be continuously reproduced by gradually changing the rotation speed.

FIG. 8 (a) shows an example of zone division of the disk of the third embodiment of the present invention and the rotational speed of the disk. In FIG. 8A, 1 is a compact disc, which indicates that it rotates at a constant rotation speed in each zone. In the first embodiment, the zone expands after access, and when further accessing from that zone, if it is in the vicinity, it can be accessed without changing the rotation speed even if it straddles the adjacent zone in the initial state, and the access time is It can be shortened. However, it is necessary to change the rotation speed when accessing beyond the widened zone instead of near access. In the third embodiment, when the access exceeds the zone thus widened, the rotation speed is gradually changed to match the rotation speed of the zone.
Therefore, since the data can be reproduced during this period, the time until the data output can be shortened.

FIG. 8B illustrates the actual operation. FIG. 8B shows the zone and the disk rotation speed after the zone 2 is accessed. In FIG. 8B, the zone 2 expands in this way, and when accessing the adjacent zone in the initial state, it is possible to access without changing the rotation speed. Then, when the access exceeds the widened zone, the rotation speed is gradually changed to match the rotation speed of the zone. Therefore, since the data can be reproduced during this period, the time until the data output can be shortened.

[0047]

Since the present invention is constructed as described above, it has the following effects.

That is, a disc recorded by the CLV system can be continuously reproduced by the MCLV system, and high speed access can be performed. Further, it is also possible to reproduce the voice by sequentially writing the reproduced data in the buffer RAM circuit and reading the written data at a constant transfer rate.

[Brief description of drawings]

FIG. 1 is a block diagram showing a disc reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a digital signal processing circuit of FIG.

FIG. 3 is a block diagram showing a conventional disc reproducing apparatus.

FIG. 4 is a block diagram showing a conventional digital signal processing circuit.

FIG. 5 is a diagram showing division and rotation speed of the disc of the first embodiment.

FIG. 6 is a diagram showing division of a disk, a rotation speed, and an operation example of the first embodiment.

FIG. 7 is a diagram showing division of a disk, a rotation speed, and an operation example of the second embodiment.

FIG. 8 is a diagram showing division of a disk, a rotation speed, and an operation example of a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Compact disc, 2 ... Optical pickup, 3 ... Spindle motor, 4 ... Slide motor, 5 ... Waveform shaping circuit, 6 ... Servo circuit, 7 ... Digital signal processing circuit, 8 ... Access control device, 11 ... Buffer RAM, 12 ... D / A conversion circuit, 13 ... RAM control device, 30 ... Rotation speed control device.

Claims (3)

[Claims] 1. A disc reproducing apparatus for reproducing data from a signal recorded on a disc-shaped recording medium, wherein an optical pickup for accessing arbitrary data on the disc-shaped recording medium, a slide motor, and controlling them. A controller and a spindle motor that divides the disc-shaped recording medium into several zones and changes the rotation speed for each zone,
And a control device for controlling the same, a waveform shaping circuit for binarizing an analog signal reproduced from the disc-shaped recording medium, a clock from the binarized data output from the waveform shaping circuit to reproduce data. A disc reproducing apparatus comprising: a signal processing circuit for demodulation; and for expanding the zone when reproducing the data across the zone, and when the zone extends despite access in the vicinity. 2. The disc reproducing apparatus according to claim 1, wherein data is reproduced from a signal recorded on a disc-shaped recording medium, and the rotational speed is gradually changed when the expanded zone is exceeded by continuous reproduction. A disk reproducing device characterized by the above. 3. The disc reproducing apparatus according to claim 1, which reproduces data from a signal recorded on a disc-shaped recording medium, wherein the rotational speed is gradually changed when the data exceeds the widened zone by accessing. A disc reproducing device characterized by.