JPH1092102A - Reproducing apparatus for disc type recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means for quickly reading a signal (Spu) when a reading position (R) is moved in a disc type recording medium reproducing apparatus (Rap) for reproducing a recording type recording medium on which data is recorded under the constant line velocity. SOLUTION: In a disc type recording medium reproducing apparatus (Rap) to produce a reproduced signal (Spu) by scanning a recording track with a pickup to read information while the disc type recording medium 1 on which information is recorded under the constant line velocity is rotated at the predetermined velocity, a CLV (line or velocity) control section 21 for rotating the disc type recording medium 1 is rotated at the constant line velocity depending on the reproduced signal (Spu, SPU), a CAV (rotational speed) control section 22 for rotating the dick type recording medium at the constant number of rotations and a reproduction drive control apparatus 20 for effectuating only one of the CLV control section 21 and CAV control section 22 depending on the position (R) of the pickup 6 are also comprised.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing head which is moved in a radial direction on a recording surface of a disk while rotating a disk-shaped recording medium, and is provided on the recording surface in a spiral or concentric manner. More specifically, the present invention relates to a disc-shaped recording medium recording / reproducing apparatus for recording / reproducing information on / from a recorded recording track. In addition, the present invention relates to a disc-shaped recording medium reproducing apparatus capable of exhibiting the best performance according to a medium, a device, and a use environment state, and a rotation speed control method thereof.

[0002]

2. Description of the Related Art In order to increase the recording density, a disk-shaped recording medium generally has a CLV in which the linear velocity of a read signal is constant.
(Constant Linear Velocity) format. Therefore, in order to ensure a constant linear velocity over the entire recording area of the disc-shaped recording medium, when reproducing the inner peripheral portion having a small reproducing radius, the disc-shaped recording medium is rotated at a high speed and the radius is large. When reproducing the outer peripheral portion, it is necessary to rotate the disk-shaped recording medium at a low speed. Therefore, when the signal reading position is changed between the inner and outer peripheral portions, not only does the recording / reproducing head for reading the recording signal move in the radial direction of the disk-shaped recording medium, but also the linear velocity of the signal to be read with respect to the recording / reproducing head increases. It is necessary to change the rotation speed of the disc-shaped recording medium so as to be constant.

FIG. 29 shows a configuration of a conventional disc-shaped recording medium reproducing apparatus RAc. On the surface of the disc-shaped recording medium 1, information is recorded on a recording track formed in a spiral or concentric manner by a magnetic, physical, or optical method. The disc-shaped recording medium 1 is placed on a turntable 2 and held from above by a clamper 3. The turntable 2 is connected to a rotating shaft 5 of a spindle motor 4 and is rotated by the spindle motor 4. The pickup 6 is driven by a traverse motor 7 on a slider 8 in the radial direction of the disc-shaped recording medium 1 to scan a recording track of the disc-shaped recording medium 1 and generate a reproduction signal Spu.

A servo controller 9 is connected to the output of the pickup 6 to amplify the reproduction signal Spu and to reproduce the reproduction signal SP.
U and outputs a traverse following error signal Sts for driving a tracking actuator built in the pickup 6 based on the tracking information in the reproduction signal Spu. That is, the servo controller 9
Is a device for controlling the variation in the traverse direction between the tracks of the pickup 6 by the traverse following error signal Sts.

[0005] The clock separator 10 is connected to the servo controller 9 to extract a clock component from the reproduced signal SPU read from the disk-shaped recording medium 1 and to generate a clock signal S
ck, and also outputs a reproduced recording signal reproduced signal SP
A data reproduction clock signal Spl is generated based on the clock component in U.

[0006] The decoder 17 is connected to the servo controller 9 and the clock separator 10 and performs various signal processings on the reproduction signal SPU based on the data reproduction clock signal Spl to be recorded on the disc-shaped recording medium 1. The reproduced data is reproduced to generate reproduction recording data Sd, and the subcode information included in the reproduction signal SPU is extracted to generate a subcode information signal Sq. Reproduction drive control device 20
Is connected to the decoder 17 and the subcode information signal S
Based on q, a traverse forced feed signal Stm for instructing the traverse movement of the pickup 6, that is, the movement of the disk-shaped recording medium 1 in the radial direction, is generated.

[0007] The traverse motor driver 19 is connected to the amplifier 9 and the reproduction drive control device 20, and generates a traverse motor drive signal Stv based on the traverse follow error signal Sts and the traverse compulsory feed signal Stm.
The traverse motor 7 has a traverse motor driver 19
To move the pickup 6 in the traverse direction.

The reference clock generator 11 outputs a reference clock signal Sr1 having a predetermined frequency. The clock signal Sck extracted from the reproduction signal Spu and the preset reference clock signal Sr1 are both input to the CLV error detector 12. The CLV error detector 12 compares the phases and frequencies of the two clock signals Sck and Sr1, finds the difference between the clocks, and outputs a CLV error signal Sc1.

The spindle motor driver 18 has a CLV
Connected to the output of the error detector 12, the CLV error signal S
A spindle motor drive signal Sm for driving the spindle motor 4 is generated based on c11. The spindle motor 4 is connected to a motor driver 18 and is driven and controlled by a spindle motor drive signal Sm to rotate the disc-shaped recording medium 1 by a predetermined method.

Further, there is provided a main controller 24 for controlling the entire operation of the disc-shaped recording medium reproducing device RAc.
The main controller 24 is provided with input means for the user to operate the disc-shaped recording medium reproducing device RAc.

The operation of the disc-shaped recording medium reproducing apparatus RAC configured as above at the time of CLV reproduction will be described below.
At the time of CLV reproduction, when the pickup 6 is reading the inner periphery of the disc-shaped recording medium 1, the spindle motor 4 adjusts the predetermined data rate based on the CLV error signal Sc1 output from the CLV control device 12. To get
It is rotated at a higher speed than when reading the outer periphery.

Now, a case where the reading area of the disc-shaped recording medium 1 changes from the inner peripheral portion to the outer peripheral portion will be described. For example, it is assumed that the user suddenly operates the disc-shaped recording medium reproducing device RAC so as to reproduce the music recorded on the outer periphery while the music recorded on the inner periphery of the music CD is being reproduced.
The reproduction area moving instruction by the user is transmitted to main controller 24.
Through the disk-shaped recording medium reproducing apparatus R as follows.
Ac.

The main controller 24 calculates the track address of the recording area corresponding to the user's designation, and inputs the calculated movement target address to the reproduction drive controller 20. The reproduction drive control device 20 outputs the subcode information signal Sq
And outputs a traverse compulsory feed signal Stm for instructing a necessary traverse movement to the traverse motor driver 19 based on the current address and the target address. As a result, the traverse motor 7 is driven to move the pickup 6 on the slider 8 from the inner peripheral portion to the outer peripheral portion of the disk-shaped recording medium 1 and onto the target recording track. The pickup 6 that has moved the target recording track on the outer periphery reads the reproduction signal Spu from the disk-shaped recording medium 1 and, after the reproduction signal Spu is amplified by the servo controller 9,
The clock signal Sck is extracted by the clock separator 10.

However, even after the pickup 6 moves from the inner peripheral portion to the outer peripheral portion, the disc-shaped recording medium 1 remains
As before, the clock frequency of the extracted clock signal Sck is increased in proportion to the radius between the movements because the clock signal Sck is rotating at a high speed. As a result, the clock frequency of the clock signal Sck is significantly higher than the clock frequency of the reference clock signal Sr1. That is, the CLV error signal S corresponding to the difference between the two clock signals Sck and Sr1
It means that the value of c1 is large.

The spindle motor driver 18 has a CLV
Finally, C is set so that the value of the error signal Sc1 becomes small.
The spindle motor 4 is driven in the deceleration direction so that the LV error signal Sc1 becomes zero. When the value of the CLV error signal Sc1 is zero, the clock frequency of the clock signal Sck is equal to the clock frequency of the reference clock signal Sr1, which means that the read data generator at the radial position of the pickup 6 on the disk-shaped recording medium 1 at that time. , Reference clock generator 1
1 means that it is equal to the reference clock signal Sr1 output.

Next, a case where the pickup 6 is moved from the outermost circumference to the innermost circumference will be described. As in the above-described case, the pickup 6 is moved from the outer peripheral portion to the inner peripheral portion based on the destination recording track address input from the main control device 24 to the reproduction drive control device 20. That is, even after the pickup 6 moves to the innermost circumference, the disc-shaped recording medium 1 is rotated at a speed that achieves a predetermined linear velocity at the outer peripheral portion. I can't get it. Therefore, the clock frequency of the clock signal Sck extracted from the reproduction signal Spu read from the inner peripheral portion of the disc-shaped recording medium 1 by the pickup 6 is higher than the clock frequency of the reference clock signal Sr1 of the reference clock generator 11. And quite low.

Therefore, if the value of the CLV error signal Sc1 is a positive value when the above-mentioned traverse from the inner peripheral portion to the outer peripheral portion is a negative value, the absolute value is similarly large. The spindle motor driver 18 sets the value of the CLV error signal Sc1 to zero, that is, drives the spindle motor 4 in the acceleration direction, and the linear velocity in the inner circumferential recording track is defined by the reference clock signal Sr1. Is converged to the specified linear velocity of the disc-shaped recording medium 1.

Since the read data rate is equal to the linear velocity of the pickup 6 with respect to the recording track of the disk-shaped recording medium 1, even when the pickup 6 moves between the inner and outer circumferences of the disk-shaped recording medium 1, the disk of the pickup 6 can be moved. CLV control in which the data rate converges constantly regardless of the radial position of the shape recording medium 1 is realized. In this sense, the clock separator 10, the reference clock generator 11, and the CL
The V control device 12 controls the C of the disc-shaped recording medium reproducing device RAC.
The CLV drive control unit 21 that performs the LV drive control is configured.

In FIG. 30, the horizontal axis represents the position R in the disk radial direction, and the vertical axis represents the rotational speed N of the disk-shaped recording medium 1.
The curve L shows the relationship between the position of the pickup 6 in the radial direction of the disk-shaped recording medium 1 and the rotational speed of the disk-shaped recording medium 1 during CLV control. In the figure, Rmin and Rmax indicate the innermost and outermost positions of the recording surface of the disc-shaped recording medium 1, respectively. Since information is recorded on the disc-shaped recording medium 1 at a constant linear velocity, the pickup 6
The information is read by changing the rotational speed N of the disc-shaped recording medium 1 in an inversely proportional relationship in accordance with the position R of. This relationship is N∝
It can be expressed as 1 / 2πR.

[0020]

However, in a disk-shaped recording medium reproducing apparatus, in response to a user's request,
There is a demand for quick access to an arbitrary portion of a recording surface of a disk-shaped recording medium at any time to read out data at high speed. For that purpose, roughly the following two measures can be considered. That is, after receiving a read command from the user, the pickup is moved to a predetermined position, and the disk-shaped recording medium is stabilized at a predetermined rotation speed at that position, and then data is actually read from the target track. To minimize the access time before starting. Another object is to maximize the scanning speed of the target track by the pickup that determines the read data rate per time.

In the conventional disk-shaped recording medium reproducing apparatus that performs CLV reproduction, the access time is reduced by reducing the rotation of the spindle motor 4 when the pickup 6 is moved from the inner periphery to the outer periphery or in the opposite direction. It is determined by the time required to increase the speed and give a prescribed linear velocity to the disc-shaped recording medium 1. That is, the rotating drive system such as the rotating disk-shaped recording medium 1, the turntable 2, the clamper 3, and the spindle motor 4 is braked with a braking force proportional to the square of the rotational speed and the mass, so that it is sharp and rapid. It is required to stably change the rotation speed.

Further, since these rotary drive systems rotate at a high speed, the amount of change in the rotational speed depending on the access position increases accordingly. For example, in the case of a CD-ROM device, the rotation speed of the CD-ROM in the conventional 1 × speed mode is as follows.
The difference is about 500 rpm at the time of reproducing the innermost part and about 200 rpm at the time of reproducing the outermost part, which is about 2.5 times at about 300 rpm. However, in the quadruple speed mode, the difference is 1200 rpm at the time of reproduction at the innermost periphery and about 800 rpm at the time of reproduction at the outermost periphery. If the torque of the spindle motor is insufficient to rapidly adjust such a large rotation speed, the waiting time for following the rotation speed increases. Therefore, a spindle motor with a large torque is required,
It is inevitable that the cost and the power consumption of the motor increase due to the enlargement of the reproducing apparatus itself due to the enlargement of the motor.

Since the read data rate changes in proportion to the scanning speed of the pickup, the scanning speed of the pickup cannot be simply determined. That is, the maximum scanning speed is determined so that the read data rate is smaller than the smaller one of the maximum processing speed of the signal processing system of the disk-shaped recording medium reproducing device or the maximum rotation speed of the rotary drive system. However, margins for deterioration factors such as variations in manufacturing quality such as the disk-shaped recording medium, the rotary drive system, and the signal processing system, changes over time such as heat generation during operation, and changes over time over a long period of use are taken into account. Therefore, it is necessary to set the maximum scanning speed to a smaller value. If the margin for this deterioration factor is insufficient, there is a problem that a malfunction occurs during use of the disc-shaped recording medium reproducing apparatus, and if it is sufficient, the inherent performance of the disc-shaped recording medium reproducing apparatus is wasted. .

Therefore, as described above, according to the present invention, any part of the recording surface of a disk-shaped recording medium can be quickly accessed at any time to read out data at high speed. It is another object of the present invention to provide a disc-shaped recording medium reproducing device that can exhibit the best performance according to the usage environment.

[0025]

In order to solve this problem, a disk-shaped recording medium reproducing apparatus of the present invention records information at a constant linear velocity on a recording track extending around the center of a recording surface. A disc-shaped recording medium reproducing apparatus that reads information from the recording track while rotating the disc-shaped recording medium at a predetermined speed, and a pickup unit that scans the recording track to generate a first reproduction signal; First rotation control means for rotating the disc-shaped recording medium at a predetermined linear velocity based on the reproduction signal, second rotation control means for rotating the disc-shaped recording medium at a predetermined rotation speed, A disc-shaped recording medium reproducing device (e.g., comprising a rotation control switching means for enabling only one of the first rotation control means and the second rotation control means based on the position of the pickup means; RAp It is intended to provide.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A disk-shaped recording medium reproducing apparatus according to an embodiment of the present invention will be described below with reference to FIGS. The same members as those of the conventional disc-shaped recording medium reproducing device already described with reference to FIG. 29 are denoted by the same reference numerals, and detailed description thereof will be omitted.

First, FIG. 1 illustrates a configuration of a disc-shaped recording medium reproducing apparatus according to a first embodiment of the present invention. The disc-shaped recording medium reproducing device RAp1 includes a disc-shaped recording medium 1, a turntable 2, a clamper 3, a spindle motor 4, a rotating shaft 5, and a pickup 6, similarly to the conventional disc-shaped recording medium reproducing device RAc shown in FIG. , Traverse motor 7,
Slider 8, servo controller 9, clock separator 10,
It has a reference clock generator 11, a CLV control device 12, a decoder 17, a spindle motor driver 18, a traverse motor driver 19, a reproduction drive control device 20, and a main control device 24. However, in this embodiment,
The reference clock generator 11 is connected to the reproduction drive control device 20 and receives the CLV setting signal Slv.

The CLV setting signal Slv is a signal generated by the reproduction drive control device 20 based on the subcode information signal Sq and indicating a predetermined constant linear velocity with respect to the position of the pickup 6. The processing capability of the decoder 17 is limited by the operation clock and the like. The maximum processable data rate at which the decoder 17 can process the reproduced signal SPU is defined as the maximum data rate Vm, and the speed obtained by converting the maximum data rate Vm to the linear velocity of the disk-shaped recording medium 1 is the maximum linear velocity L.
vm.

The disc-shaped recording medium reproducing device RAp1 further has a CAV control unit 22 and a drive control switching unit 16. The CAV drive control unit 22 includes a frequency generator 13, a reference frequency generator 14, and a CAV error detector 15. The frequency generator 13 is connected to the spindle motor 4 and generates a spindle rotation signal Sfg having a frequency proportional to the rotation speed of the rotating shaft 5. The reference frequency generator 14 controls the CA supplied from the reproduction drive control device 20.
A reference frequency signal Sr2 is generated based on the V setting signal Sav. The CAV setting signal Sav is a signal that is generated by the reproduction drive control device 20 based on the subcode information signal Sq and indicates a predetermined constant rotation speed with respect to the position of the pickup 6. Like the CLV error detector 12, the CAV error detector 15 compares the phase and frequency of the reference frequency signal Sr2 with the spindle rotation signal Sfg and outputs a CAV error signal Sc2.

The drive control switching unit 16 is connected to the outputs of the CLV error detector 12 and the CAV error detector 15,
CLV error signal Sc1 and CAV error signal Sc2
Is entered. Further, the drive control switching unit 16 controls the drive control unit selection signal Ss supplied from the reproduction drive control device 20.
A selection switch that outputs one of the input CLV error signal Sc1 and CAV error signal Sc2 to the spindle motor driver 18 based on w. The reference clock generator 11 and the reference frequency generator 14 not only output the frequencies indicated by the reference signal setting signals Slv and Sav from the reproduction drive control device 20 as shown in the present embodiment, but also generate the generator 11 And 14 may output the frequency based on predetermined frequency data prepared in advance. The control section selection signal Ssw is 0
When the signal is (zero), the signal is a binary signal indicating the CLV control unit 21, and when the value is 1 (one), the signal is a binary signal indicating the CAV control unit 22.

As described above, the CAV control unit 22 is provided even in the disk-shaped recording medium 1 on which the CLV is recorded, if the CAV is reproduced from the inner peripheral part, the disk-shaped recording medium is changed according to the position of the pickup 6. This is because there is no need to control the rotational speed of the medium 1, which is advantageous for shortening the access time. However, due to the performance of the spindle motor and other mechanical mechanisms, there is an upper limit to the permissible rotation speed. Furthermore, when the allowable rotation speed is increased, there is an upper limit on the data rate due to the processing speed of the signal processing circuit. A method for setting these factors in a well-balanced manner and optimizing reproduction will be described below.

[0032]

First Embodiment First, a first embodiment of the disc-shaped recording medium reproducing apparatus RAP1 based on the embodiment of the present invention shown in FIG. 1 will be described. With reference to FIG. 2, the operation of the disc-shaped recording medium reproducing device RAP1 according to the present embodiment will be briefly described.
Similarly to the case shown in FIG. 24, when the position in the disk radial direction is R on the horizontal axis and the number of revolutions of the disk-shaped recording medium 1 is N on the vertical axis, the rotation in the disk-shaped recording medium reproducing device RAp1 The change in speed is indicated by a solid line L1. A change in the number of revolutions by the conventional disc-shaped recording medium reproducing device RAc is indicated by a broken line L. In the present embodiment, the recording area of the disc-shaped recording medium 1 is determined by a predetermined radial position R1 between the innermost peripheral portion Rmin and the outermost peripheral portion Rmax, and the CLV region Ac on the inner peripheral portion side.
lv (Rmin to R1) and the CAV region Ac on the outer peripheral side
av (R1 to Rmax). In addition, CLV
In the region Aclv, the broken line L overlaps with the solid line L1.
In this way, the reproduction control is performed for the predetermined radial position R1 as described below.

In the disc-shaped recording medium reproducing device RAp1, a predetermined position R is set from the innermost peripheral portion Rmin to the outer peripheral portion.
Up to 1, the reproduction drive control device 20 controls the drive control switching unit 16 to operate the CLV control unit 2 by the drive control unit selection signal Ssw.
1 is supplied to the spindle motor driver 18 to control the CLV reproduction.
When reaching the predetermined position R1, the reproduction drive control device 20
In response to the drive control section selection signal Ssw, the drive control switching section 16 supplies the CAV error signal Sc2 from the CAV control section 22 to the spindle motor driver 18 and controls the spindle motor driver 18 to perform CAV reproduction. That is, the radius position R1 is a switching point of the control between the CLV control and the CAV. When the traverse movement of the pickup 6 occurs between the CLV area and the CAV area, the CLV error signal Sc1 and the CAV
By switching with the error signal Sc2, the access time can be minimized.

In FIG. 2, radial positions Rmin, R1,
And Rmax at the time of the conventional CLV control are represented by N (Rmin), N (R1),
And N (Rmax). In this example, the fluctuation in the number of revolutions in the CLV region Aclv is maximum when the pickup 6 moves from the radial position Rmin to R1. CAV
In the region Acav, the rotation speed N is constant at N (R1) regardless of the position of the pickup 6. That is, in the present embodiment, through the entire recording area of the disc-shaped recording medium 1,
The maximum rotation speed variation dN1 can be calculated by the following equation.

## EQU1 ## dN1 = N (Min) -N (R1)

On the other hand, in the conventional disc-shaped recording medium reproducing apparatus, since the entire recording area of the disc-shaped recording medium 1 is controlled by CLV, the maximum rotational speed fluctuation dNclv can be calculated by the following equation. It becomes maximum when moving from to Rmax.

## EQU2 ## dNclv = N (Rmin) -N (Rmax)

It should be noted that the CAV region Aav also has a CL
The maximum rotational speed fluctuation amount dN2 when V control is performed can be calculated by the following equation.

## EQU3 ## dN2 = dNclv-dN1 = N (R1) -N
(Rmax)

As described above, by dividing the recording area of the disk-shaped recording medium 1 into two parts and switching between the CLV control and the CAV control, the maximum rotational speed fluctuation amount dN1 becomes N (R1)-
N (Rmax) can be reduced. Further, in the CAV region where the number of rotations is constant, the speed of the spindle motor 4 is not changed even if the pickup 6 moves in the radial direction of the disk-shaped recording medium 1, so that the recording signal of the disk-shaped recording medium 1 is transmitted immediately after the movement. Can be read. On the other hand, CAV region Aca
Also, when the pickup 6 moves over the CLV region Aclv with the constant linear velocity, the change in the number of revolutions can be reduced as compared with the control in which the entire circumference of the disc-shaped recording medium 1 is rotated at the constant linear velocity. Can reduce the waiting time (access time) required to change the rotation speed,
Information can be quickly extracted from the disk-shaped recording medium 1.

Next, the operation of the disc-shaped recording medium reproducing device RAp1 will be described in detail with reference to the flowchart shown in FIG. When the reproducing operation starts, in order for the pickup 6 to start reading the disk-shaped recording medium 1 from the innermost peripheral portion Rmin side, first, in step S1, the control section selection signal Ssw is set.
Is set to 0, the CLV error signal Sc1 is connected to the spindle motor driver 18 by the drive control switching unit 16, and CLV control is started at a predetermined initial rotation speed N (Rmin). In step S3, the TOC information is read, and the position of the control switching point R1 is set based on the read TOC information and a predetermined area dividing method.
In step S5, the decoder 17 generates the subcode information signal Sq from the reproduction signal SPU reproduced from the disc-shaped recording medium 1. In step S7, the position R on the current radius of the pickup 6 is calculated by the reproduction drive control device 20 based on the subcode information signal Sq. In step S9, it is determined whether or not the current position R of the pickup 6 is located on the inner peripheral side of the control switching point R1. In the case of YES, the process proceeds to step S11. In step S11, the control section selection signal Ssw continues to be 0.
After the setting, the process proceeds to step S13. Step S1
In 3, since the control section selection signal Ssw is 0, the drive control switching section 16 continues to select the output CLV error signal Sc1 of the CLV control section 21. In step S15, C
The LV error signal Sc1 is input to the spindle motor driver 18, and the CLV control is continued. Then, the process proceeds to the next step S23.

In step S23, it is determined whether or not the current position R of the pickup 6 has reached the outermost peripheral portion Rmax. In the case of YES, it is assumed that the reproduction of the entire recording area of the disc-shaped recording medium 1 has been completed, and the reproduction processing ends.
On the other hand, if NO, the process returns to step S5,
Steps S11 and S1 until NO is determined in Step 9
3, the processing of S15, S5, S7, and S9 is repeated.
On the other hand, if NO in S9, that is, if it is determined that the pickup 6 is located on the outer peripheral side of the control switching point R1,
Proceed to step S17. In this way, when the entire area of the recording area is accessed from the inner circumference to the outer circumference,
The end of the operation is suitable for a sequentially recorded disc-shaped recording medium such as a music CD. However, if necessary, an arbitrary part of the recording area of the disc-shaped recording medium 1 is randomly accessed according to an instruction from the data main controller 24, not only in a database application but also in a music CD or the like. Needless to say, it may be configured to end the processing by accessing a predetermined area.

If it is determined as NO at step S9, the process proceeds to step S17. And step S
After the control unit selection signal Ssw is set to 1 at 17, the process proceeds to step S19. In step S19, since the control unit selection signal Ssw is 1, the drive control switching unit 16
The CAV error signal Sc2 output from the AV control unit 22 is selected. In step S21, after the CAV error signal Sc2 is input to the spindle motor driver 18 and the CAV control is performed, the process proceeds to step S23, and the end of the reproduction is determined.

As described above, the disc-shaped recording medium reproducing apparatus R
Not only when Ap1 starts the reproducing operation and the disc-shaped recording medium 1 is sequentially reproduced from the inner peripheral side toward the outer peripheral side, but also when the reproduction target portion suddenly changes from the outer peripheral side to the inner peripheral side. Similarly, according to the current position R of the pickup 6,
The control can be switched to the control appropriate for the reproduction target area without delay. That is, according to the present embodiment, when reproducing the entire recording area of the disc-shaped recording medium 1, the control is not performed at a constant linear velocity as in the conventional disc-shaped recording medium reproducing apparatus. The control method is changed to a CAV region in which a constant control is performed and a CLV region in which the inner peripheral side is controlled at a constant linear velocity as in the related art. As a result, a recording signal can be read out immediately after the movement of the pickup in the CAV area on the outer peripheral portion. Further, even when the pickup moves across the CAV area and the CLV area, an excellent disc-shaped recording medium reproducing apparatus capable of quickly extracting information with a short waiting time required for changing the rotation speed of the disc-shaped recording medium is provided. can do.

[0042]

Embodiment 2 Hereinafter, a second embodiment of the disc-shaped recording medium reproducing device RAp1 according to the present embodiment will be described with reference to FIGS. Normally, the disc-shaped recording medium 1 is recorded in order from the inner circumference side. Therefore, when the information recording amount is small, only the inner circumference of the disc-shaped recording medium 1 is often used. For this purpose, in this embodiment, as described below, the inner peripheral side of the disc-shaped recording medium 1 is optimized for reproduction. First, with reference to FIG. 4, the operation of the disc-shaped recording medium reproducing device RAP1 according to the present embodiment will be briefly described. As in the case of the first embodiment shown in FIG.
The change in the rotation speed in the disc-shaped recording medium reproducing device RAp1 is represented by a solid line L2, and the change in the rotation speed is represented by the conventional disc-shaped recording medium reproducing device RAc.
The change in the rotation speed due to the rotation is represented by a broken line L. Further, the conventional CL at the radial positions Rmin, R2, and Rmax
The rotation speed at the time of V control is set to N (Rmin), N
(R2) and N (Rmax). In this embodiment,
The disc-shaped recording medium 1 is divided into a CAV area Acav on the inner peripheral side (Rmin to R2) and a CLV area Aclv on the outer peripheral side (R2 to Rmax) at a predetermined radial position R2. In this manner, reproduction control is performed on the bisected disc-shaped recording medium 1 at a predetermined radial position R2 as described below.

Also in this example, the rotation speed is N in the CAV region Acav from the innermost peripheral portion Rmin to the switching position R2.
(Rmin) is controlled to be constant. In the CLV region Aclv from the switching position R2 to the outermost peripheral portion Rmax, the CLV is the same as in the conventional CLV control indicated by the broken line L.
Controlled. That is, in the CLV region Aclv region, the solid line L2 in this example has a value k times (k is a number of 1 or more) the broken line L, but the rotation speed at which the CLV control is started is N (R2). N (Rmin). That is, C
In the LV area Aclv, the solid line L2 is k
The rotation speed is twice as high. The rotation speed NP (Rmax) at the radial position Rmax according to the present invention represented by the solid line L2 is expressed by the following equation.

NP (Rmax) = kN (Rmax), and in the present embodiment, k = R2 / Rmin.

Therefore, the maximum rotational speed variation d in this embodiment
N3 is represented by the following equation.

DN3 = N (Rmin) −NP (Rmax) = N (Rmin) −R2 · N (Rmax) / Rmin = N (R2) −R2 · N (Rmax) / Rmin

On the other hand, in the conventional disk-shaped recording medium reproducing apparatus, the maximum rotational speed variation dNclv is always expressed by the following equation.

## EQU6 ## dNclv = N (Rmin) -N (Rmax)

The maximum rotational speed variation dN3 in the present invention
And the difference dN between the conventional maximum rotational speed fluctuation amount dNclv is expressed by the following equation. In other words, in the present invention,
dN can also be reduced.

DN = dNclv−dN3 = N (Rmin) −N (Rmax) − {N (Rmin) −R2 · N (Rmax) / Rmin} = (R2 / Rmin−1) · N (Rmax)

In the above formula 7, R2 / Rmin> 1
Therefore, dN is a positive number, and the change in the number of revolutions can be reduced accordingly. The basic operation in this embodiment is the same as that in the first embodiment described with reference to FIGS. 2 and 3 except that the control method at the inner and outer peripheral portions is different. Are the same. Therefore, with reference to the flowchart shown in FIG. 5, a brief description will be given focusing mainly on differences from the first embodiment. When the reproducing operation starts, the control unit selection signal Ssw is first set to 1 in step S51 so that the pickup 6 starts reading from the innermost peripheral portion Rmin side of the disc-shaped recording medium 1, and the drive control switching unit 16 C
The AV error signal Sc2 is connected to the spindle motor driver 18 to start the CAV control. In step S53, the position of the control switching point R2 is set to a predetermined address. Based on the radial position R of the pickup 6 calculated in steps S55 and S57, it is determined in step S59 whether the current position R of the pickup 6 is located on the inner peripheral side of the control switching point R2. You.

In the case of YES in step S59, after the control section selection signal Ssw is continuously set to 1 in step S61, the CAV error signal Sc2 is continuously selected in step S63, and the CAV control is continued in step S65. If it is determined in step S73 that the reproduction operation has not been completed, the process returns to step SS55.

On the other hand, if NO in step S59, that is, if it is determined that the pickup 6 is located on the outer peripheral side of the control switching point R2, the control unit selection signal Ssw is set to 0 in step S67, and CLV in S69
The error signal Sc1 is selected, the CLV control is performed in step S71, and the process proceeds to step S73.

In addition to the case where the reproduction is performed in order from the inner circumference to the outer circumference of the disc-shaped recording medium 1, the same applies to the case where the portion to be reproduced suddenly changes from the outer circumference to the inner circumference. Needless to say, the control can be switched to the control suitable for the reproduction target area without delay according to the current position R of No. 6. Also, the predetermined linear velocity is equal to the pickup 6
May be set so that the speed of the signal read in step (1) becomes a speed that the decoder 17 can process. In this case, the reproduction signal SPU read by the pickup 6 is processed by the decoder 17 after the rotation speed of the disc-shaped recording medium 1 reaches a predetermined linear velocity. With this configuration, the change in the rotation speed of the disk-shaped recording medium can be made smaller than the change in the rotation speed when the entire circumference of the disk is reproduced at a constant linear velocity.
This disc-shaped recording medium reproducing device can read information quickly.

As described above, according to the disk-shaped recording medium reproducing apparatus of the present embodiment, all areas are not controlled at a constant linear velocity as in the conventional disk-shaped recording medium reproducing apparatus, but are arbitrarily determined. By performing CAV control at a constant rotation speed in an inner region from a predetermined reproduction position, a recording signal can be read out immediately after the movement of the pickup in the constant rotation speed region. Provided is an excellent disc-shaped recording medium reproducing apparatus that can reduce a change in the number of revolutions and can quickly read out a recording signal even when the pickup 6 moves within a CLV region where the linear velocity between the inside and the outside is constant. Can be.

[0052]

Embodiment 3 Hereinafter, a third embodiment based on the embodiment of the present invention will be described with reference to FIGS. 6, 7, and 8. FIG. This embodiment is intended to improve the reproduction control according to the first embodiment described with reference to FIGS.
In the first embodiment, C outside the control switching point R1
Since the CAV control for rotating the AV area Acav at a constant rotation speed N (R1) is performed, the linear velocity increases in proportion to 2πR · N (R1). Further, the read data rate in the CAV area Acav increases as the rotation speed N (R1) increases, and reaches a maximum at the outermost peripheral portion Rmax. Therefore, when the rotational speed of the disk-shaped recording medium 1 increases, the CAV area Acav
In this case, the linear velocity of the reproduced signal is significantly increased, the signal frequency is increased, and may exceed the maximum data rate Vm which is the maximum processing capability of the decoder 17.

That is, the number of revolutions N (R
If 1) is set high, the data rate of the reproduction signal SPU (Spu) exceeds the maximum data rate Vm of the decoder 17 before reaching the outermost peripheral portion Rmax of the disc-shaped recording medium 1, and the maximum from the control switching point R1. The area up to the outer peripheral portion Rmax cannot be completely reproduced. Also, if the rotation speed N (R1) is set low, the data rate of the reproduced signal SPU is much lower than the maximum linear velocity Lvm of the decoder 17 even when the outermost peripheral portion Rmax is reached, and the disc-shaped recording medium reproducing device Rap1 is Performance cannot be fully utilized. In other words, the data rate of the reproduction signal SPU is equal to the outermost peripheral portion Rmax.
Is desirably set to be equal to or less than the maximum linear velocity Lvm.

Therefore, in the present embodiment, the maximum allowable rotation speed N at which the data rate of the reproduction signal Spu becomes the maximum linear velocity Lvm of the decoder 17 at the outermost peripheral portion Rmax of the disc-shaped recording medium 1.
Find max (Rmax). Then, the control switching point R1
By setting the rotation speed N (R1) of the disc-shaped recording medium 1 at or below the maximum allowable rotation speed Nmax (Rmax), the reproduction signal Spu is output over the entire CAV area Acav.
Is maintained at the maximum data rate Vm or less, the performance of the disc-shaped recording medium reproducing device Rap1 can be effectively performed, and the entire recording area of the disc-shaped recording medium 1 can be reproduced. Similarly, the radial position Rmax may be obtained from the maximum allowable rotation speed Nmax (Rmax).

FIG. 6 shows a control switching point R1 in this embodiment.
The rotation speed N (R1) at the maximum allowable rotation speed Nmax (Rm
ax) will be described. Inner circumference Rmi
n, the outermost peripheral portion Rmax, and the maximum linear velocity L of the decoder 17
vm, C in the disc-shaped recording medium reproducing apparatus RAp1
The maximum allowable rotation speed Nmax (Rmax) during the LV control, that is, the maximum rotation speed at the outermost peripheral portion Rmax can be obtained. Nmax (Rmax) is calculated according to the following equation.

Nmax (Rmax) = Lvm / 2π · Rmax

Next, when CAV reproduction is performed on the entire circumference of the recording area of the disc-shaped recording medium 1, the maximum allowable rotation speed Nmax (R
The radius position R3 that reaches (max) is obtained. The rotation speed N (R3) at the radius position R3 can be expressed by the following equation.

N (R3) = C / 2π · R3 = Nmax (Rmax) = Lvm / 2π · Rmax, where C is a constant

The CLV limit position R3 can be expressed by the following equation.

R3 = F (N (Rmax)) = C · Rmax
/ Lvm

By setting the CLV limit position R3 as the control switching point R1 in the first embodiment, the CAV region Aav can be set to the CV range without causing the decoder 17 to overflow.
AV playback is possible. FIG. 6 shows a radial position R in the present embodiment.
And the rotational speed N are indicated by a solid line L3, and the conventional relationship is indicated by a broken line L.

FIG. 7 schematically shows a sectional view along the diameter of the disk-shaped recording medium 1. The disk-shaped recording medium 1 has a maximum recording area recordable by the system between the innermost peripheral portion Rmin and the outermost peripheral portion Rmax. Management information and the like by the system are recorded from the innermost peripheral portion Rmin to the outer peripheral portion, and then the user data is sequentially stored in the outermost peripheral portion Rmin.
Recording is performed up to the recording outer peripheral portion Rue toward max.
When data is recorded on the entire recording area, it goes without saying that the recording outer peripheral portion Rue coincides with the outermost peripheral portion Rmax.

As an example of the disc-shaped recording medium 1, a CD-RO
In the case of M, the innermost peripheral portion Rmin
Information indicating where and what data is recorded on the CD-ROM, that is, TOC (Table of Contents)
Is recorded. The reproduction drive control device 20 uses the TOC included in the subcode information signal Sq to calculate the recording outer circumference Ru.
The position of e can be known. Now, in the recording area of the disc-shaped recording medium 1 recorded in this way, a part from the radial position Ru1 to the radial position Ru2 located between Rmin and the recording outer peripheral part Rue is accessed to reproduce data. Think. In addition, the specifications including the innermost peripheral portion Rmin and the outermost peripheral portion Rmax are usually set at a predetermined radial position for each type of the disk-shaped recording medium 1 in many cases. If necessary, the user can know the information. Therefore, the user may input necessary information to the reproduction drive control device 20 through the main control device 24. However, it is preferable to read the TOC information in order to know the actual recording state of the recording surface of the disc-shaped recording medium 1.

The operation of the disc-shaped recording medium reproducing device RAp1 in this embodiment will be described with reference to the flowchart of FIG. In the present embodiment, step S3 of the flowchart shown in FIG.
3, replaced by S105, S107, and S109.

When the reproducing operation starts, the control section selection signal Ssw is set to 0 in S1, and then the TOC information is read in step S101. In step S103, the outermost peripheral portion Rmax is obtained. In step S105, the maximum allowable rotation speed Nmax is obtained based on the maximum linear velocity Lvm and the outermost peripheral portion Rmax. In step S107, the CLV limit position R3 is calculated. Then, in step S109,
After setting the value of the CLV limit position R3 calculated in step S107 as the control switching point R1, the process proceeds to step S5. Thereafter, the operation based on the first embodiment described with reference to FIG. 3 is performed.

As described above, according to the present embodiment, not all areas are controlled at a constant linear velocity as in the conventional disk-shaped recording medium reproducing apparatus, but are controlled so that the linear velocity is constant. During reproduction of the disc-shaped recording medium, a disc-shaped signal when the reproduction signal when the linear velocity is increased by increasing the rotation speed in the outermost periphery reproduction of the disc-shaped recording medium has reached the limit frequency that the decoder 17 can process. By performing rotation control in a region outside the position where the rotation speed of the recording medium has reached the rotation speed so that the rotation speed is kept constant, a recording signal can be read immediately after the movement of the pickup in the rotation speed constant region. In addition, even when the pickup moves over a region where the rotation speed is constant and a region where the linear velocity is constant, the waiting time required for changing the rotation speed of the disk-shaped recording medium is short, and information is quickly retrieved. It is possible to provide a superior disk-shaped recording medium reproducing apparatus capable.

[0064]

Embodiment 4 Hereinafter, a fourth embodiment based on the embodiment of the present invention will be described with reference to FIGS.
This embodiment is a modification of the third embodiment described with reference to FIGS. 6, 7, and 8. In the third embodiment, the number of revolutions N (R1) at the control switching point R1 = Nmax (Rmax
x) was set to N (Rmax), that is, the data rate of the reproduced signal Spu was equal to or less than the maximum linear velocity Lvm at the outermost peripheral portion Rmax. However, as shown in FIG. 7, when the recording is performed only up to the recording outer peripheral portion Rue (Rmax ≠ Rue), it is not necessary to reproduce the area (Rue to Rmax) on the outer peripheral side from the recording outer peripheral portion Rue. It may be set so that the recording outer peripheral portion Rue is equal to or less than the maximum linear velocity Lvm.

Therefore, as shown in FIG. 9, in the present embodiment, the maximum allowable rotational speed Nmax (Rue) at which the data rate of the reproduced signal Spu becomes the maximum linear velocity Lvm of the decoder 17 at the recording outer peripheral portion Rue of the disc-shaped recording medium 1 is used. ). Then, the rotational speed N of the disc-shaped recording medium 1 at the control switching point R1
By setting (R1) to be equal to or less than the maximum allowable rotation speed Nmax (Rue), the data rate of the reproduced signal Spu is maintained at or below the maximum data rate Vm over only the area of the CAV area Acav where data is actually recorded. Thus, the performance of the disc-shaped recording medium reproducing device RAp1 can be effectively used, and the entire recording area of the disc-shaped recording medium 1 can be reproduced.

That is, the innermost peripheral portion Rmin and the recording outer peripheral portion R
ue and the maximum linear velocity Lvm of the decoder 17, the maximum permissible rotational speed Nmax (Rue) during CLV control in the disc-shaped recording medium reproducing device RAp1, that is, the recording outer peripheral portion Ru.
The maximum rotation speed Nmax at e can be obtained.

Nmax (Rue) = Lvm / 2πRue

Next, when the recording area of the disk-shaped recording medium 1 is CAV-reproduced from the control switching point R1 to the recording outer peripheral portion Rue, a radial position R4 reaching the maximum allowable rotation speed Nmax (Rue) is obtained. The CLV limit position R4 can be expressed by the following equation.

R4 = F (Nmax (Rue))

Incidentally, R4 is also a constant C, an outermost radius position Rmax, and a maximum linear velocity L, similarly to R3 shown in the above equation (10).
vm. This CLV limit position R4 is
By setting the control switching point R1 in the first embodiment,
CA can be performed at the best efficiency according to the actual use situation of the CAV area Aav without causing the decoder 17 to overflow.
V playback. FIG. 9 shows the relationship between the radial position and the number of revolutions in the present embodiment by a solid line L4.

The operation of the disc-shaped recording medium reproducing device RAp1 in this embodiment will be described with reference to the flowchart of FIG. In this embodiment, similar to the third embodiment,
Step S3 in the flowchart shown in FIG. 3 is replaced with steps S151, S153, S155, S157, and S159 below.

When the reproducing operation is started, first, in S1, the control section selection signal Ssw is set to 0, and then in step S1
At 51, the TOC information is read. TO in step S153
The recording outer peripheral position Rue is obtained based on the C information. In step S155, the maximum linear velocity Lvm and the recording outer peripheral area Rue
, The maximum allowable rotation speed Nmax (Rue) is obtained. In step S157, the CLV limit position R4 is calculated. Then, in step S159, the value of the CLV limit position R4 calculated in step S157 is set as the control switching point R1, and the process proceeds to step S5. Thereafter, the operation based on the first embodiment described with reference to FIG. 3 is performed.

According to the disc-shaped recording medium reproducing apparatus according to this embodiment, the maximum permissible rotational speed Nmax is obtained at the outermost peripheral portion Rmax of the CAV area Acav of the disc-shaped recording medium 1 as in the third embodiment. Instead of the maximum permissible rotational speed Nma at the recording outer circumference Rue where data is actually recorded.
By obtaining x, CAV can be reproduced more quickly and efficiently.

[0072]

Fifth Embodiment A fifth embodiment based on the embodiment of the present invention will be described below with reference to FIGS. This embodiment is a further modification of the fourth embodiment described with reference to FIGS. In the fourth embodiment, the maximum permissible rotational speed Nmax is determined not based on the outermost peripheral portion Rmax but on the basis of the recording outer peripheral portion Rue, and is not the entire CAV region Acav but the actually recorded region (R1).
To Rue) to perform optimized CAV control. However, in the present embodiment, as shown in FIG. 7, furthermore, the maximum permissible area (Ru1 to Ru2) of the actually reproduced CAV area (R1 to Rue) is recorded. Rotation speed Nmax
Is to be optimized. However, it is the outermost peripheral position of the target CAV area that determines the maximum allowable rotation speed Nmax as described above. FIG. 11 shows the relationship between the radial position and the rotational speed in the present embodiment by a solid line L5.

With reference to the flowchart of FIG. 12, the operation of the disc-shaped recording medium reproducing device RAp1 according to the present embodiment will be briefly described. In the present embodiment, similarly to the fourth embodiment, step S3 of the flowchart shown in FIG. 3 is replaced by the following steps S201, S203, S205, and S20.
7 and S209.

When the reproducing operation is started, first, in S1, the control section selection signal Ssw is set to 0, and then in step S2
At 01, the TOC information is read. TO in step S203
The reproduction outer peripheral portion Ru2 is obtained based on the C information. In step S205, the maximum linear velocity Lvm and the reproduction outer peripheral portion Ru2
And the maximum allowable rotation speed Nmax based on the following equation:
(Ru2) is obtained.

Nmax = Lvm / 2π · Ru2

At step S207, the CLV limit position R5 is calculated. Then, in step S209, step S2
After setting the value of the CLV limit position R5 calculated in 07 as the control switching point R1, the process proceeds to step S5.

According to the disc-shaped recording medium reproducing apparatus according to this embodiment, as in the case of the fourth embodiment, the recording outer peripheral portion Rue of the disc-shaped recording medium 1 where data in the CAV area Acav is recorded is recorded. In addition, the CAV can be reproduced more quickly and efficiently by obtaining the maximum allowable rotation speed Nmax at the reproduction outer peripheral portion Ru2 actually reproduced this time.

[0077]

Embodiment 6 Hereinafter, a sixth embodiment of the disc-shaped recording medium reproducing apparatus RAp1 according to the present embodiment will be described with reference to FIGS. In this embodiment, FIGS.
And a method for optimizing the radial position of the control switching point R2 and the initial rotational speed N (Rmin). That is, if the initial rotation speed N (Rmin) at the innermost peripheral portion Rmin is determined, the reproduced reproduction signal Sp
CAV at which the data rate of u becomes the maximum data rate Vm
The optimum position R6 of the control switching point R2 of the single section of the area Acav can be obtained. If the position R6 of the control switching point R2 is determined, the optimum rotation speed Nm of the initial rotation speed N (Rmin) is determined.
ax (R6) can be determined.

Referring to FIG. 13, optimization of the control switching point R2 and the initial rotation speed N (Rmin) in this embodiment will be described. In the figure, the relationship between the radial position and the rotational speed based on the present embodiment is indicated by a solid line L6, and the relationship between the radial position and the rotational speed during the conventional CLV control is indicated by a broken line L. To optimize the control switching point R2, first, a predetermined initial rotational speed N (Rmi
The maximum data rate radius position R6 is calculated based on n). A radial position R6 'on the inner peripheral side of the radial position R6 is determined by a predetermined distance ΔR determined in consideration of the performance variation of the signal processing system such as the decoder 17, and is set as a control switching point R2.

To optimize the initial rotation speed N (Rmin), the maximum allowable rotation speed Nmax (R2) is calculated based on a predetermined control switching point R2, and the maximum data rate radial position R6 is calculated. A rotation speed equal to or less than the calculated maximum allowable rotation speed Nmax (R2) is set as the initial rotation speed N (Rmin) in consideration of variations in the performance of the signal processing system.

By setting as described above, in the CAV area Acav inside the radial position R2 (R6 '), the data rate of the reproduced signal Spu is kept at the maximum data rate Vm or less, and the disc-shaped recording medium reproducing apparatus Rap1 is maintained.
This makes it possible to reproduce the entire recording area of the disc-shaped recording medium 1 effectively, and to eliminate the waiting time for the rotation speed following which affects the reading of information. Further, the pickup 6 is connected to the CAV area Aav and CL.
Even in the case of suddenly crossing the boundary with the V region Aclv, the delay time required for reading from the disc-shaped recording medium 1 can be minimized by switching the control method instantaneously.

The operation of the disc-shaped recording medium reproducing device RAp1 in this embodiment will be briefly described with reference to the flowchart of FIG. In the present embodiment, step S53 of the flowchart shown in FIG.
1, S253, S255, and S257.

When the reproducing operation is started, first, in step S51, the control unit selection signal Ssw is set to 1 and then in step S51.
At 251 the TOC information is read. In step S253,
The maximum data rate radial position R6 is calculated based on the preset initial rotational speed N (Rmin) and the maximum linear velocity Lvm according to the following equation.

R6 = Lvm / 2π · N (Rmin)

In step S255, a radial position R6 'on the inner peripheral side by a predetermined distance ΔR from the inner peripheral side of R6 is set.
After setting R6 ′ as the control switching point R2 in step S257, the process proceeds to step S55.

Next, referring to FIG. 15, the initial rotational speed N (R
min) will be briefly described. In optimizing the initial rotation speed N (Rmin), step S53 of the flowchart shown in FIG.
1, S303, S305, and S307.

When the reproducing operation is started, first, in step S51, the control unit selection signal Ssw is set to 1 and then in step S51.
At 301, the TOC information is read. In step S303,
Based on the preset control switching point R2 and the maximum linear velocity Lvm, an initial rotation speed N (Rmin) is calculated according to the following equation.

N (Rmin) = Lvm / 2π · R2

In step S305, a rotation speed N (Rmin) 'lower than N (Rmin) by a predetermined rotation speed △ N is set. In step S307, N (Rmin) 'is changed to Nm
After setting as ax (Rmin), the process proceeds to step S55.

With the above-described configuration, according to the disc-shaped recording medium reproducing apparatus of the present embodiment, the CAV area A of the disc-shaped recording medium 1 is different from that of the second embodiment.
Cav can be reproduced more efficiently.

[0088]

Embodiment 7 Hereinafter, a seventh embodiment based on the present embodiment will be described with reference to FIGS. 16, 17, 18, and 19. FIG. As shown in FIG. 16, the disc-shaped recording medium reproducing apparatus Rap2 according to the present embodiment is different from the disc-shaped recording medium reproducing apparatus Rap1 shown in FIG.
And receives the decoder monitor signal SST indicating its own signal processing state to the decoder 17, and
7 generates a decoding abnormality signal Sng indicating whether or not the reproduction signal SPU is normally decoded. The decoder 17
As a typical example of when it cannot decode correctly,
Overflow in which a signal with a rate exceeding the processing capability of the decoder 17 is input, rate fluctuation of the input signal due to rotational fluctuation of the disc-shaped recording medium 1, poor reading of the input signal, and the like are raised. If the reproduction signal SPU is correctly decoded, the decoding abnormality signal Sng is set to low; otherwise, the decoding abnormality signal Sng is set to high and output to the reproduction drive control device 20. In this embodiment, the decoding error signal Sng
Is a binary signal indicated by low (0) and high (1).

The reproduction drive control unit 20 determines that the linear velocity at the current position of the pickup 6 is too high while the decoder 17R cannot process the reproduction signal SPU while the decode abnormality signal Sng is high. 4 is gradually decelerated and the data rate of the reproduction signal SPU is gradually reduced. When the data rate of the reproduction signal SPU reaches the maximum data rate Vm of the decoder 17R,
Since the decoder 17 can correctly decode the reproduction / recording signal SPU, the decoding abnormality signal Sng is set to low (0), and the reproduction drive control device 20 ends the deceleration control of the spindle motor 4.

The operation of the disc-shaped recording medium reproducing device RAp2 in this embodiment will be described with reference to the flowchart of FIG. In the present embodiment, step S59 of the flowchart shown in FIG.
1, S353, S355, S357, S359, S3
61, and S363.

When the reproducing operation is started, first, as described above, through steps S51, S53, S55, and S57, CAV control at the initial rotation speed N (Rmin) is performed, and the process proceeds to step S351.

In step S351, it is determined whether or not the decoding abnormality signal Sng is 0, that is, whether the data rate of the reproduction signal SPU does not exceed the maximum data rate Vm of the decoder 17R. If not exceeded, it is determined as YES, and the process proceeds to the CAV control step S61, and the CAV control based on the second embodiment is continued. On the other hand, when the decoding error signal Sng is 1, it is determined that the data rate of the reproduction signal SPU is higher than the maximum data rate Vm, and the process proceeds to step S353.

In step S353, the initialization rotation speed N
After (Rmin) is reduced by the predetermined number of revolutions △ N, the process proceeds to step S355. Note that the predetermined rotation speed ΔN can be an arbitrary fractional value of the resolution of the spindle rotation signal Sfg.

In step S355, step S353
After the CAV control is performed at the rotation speed N (Rmin) reduced by the above, the process proceeds to step S357. The content of the CAV control performed in step S355 is the same as the control in steps S61, S63, and S65 described above.

In step S357, it is determined again whether or not decode abnormal signal Sng is zero. If no,
It is determined that the deceleration of the spindle motor 4 in Step S353 is insufficient, and the process returns to Step S353 and returns to ΔN.
CAV control is performed only at a reduced speed. On the other hand, in the case of YES, further deceleration of the spindle motor 4 is not necessary, so the flow proceeds to step S359.

In step S359, R obtained in step S57 and N (Rmi obtained in step S353)
Based on n), the maximum linear velocity Lvm1 is calculated according to the following equation.

Lvm1 = 2π · R

Thus, the maximum linear velocity Lvm1
Is the actual maximum linear velocity according to the variation of the individual performance of the disc-shaped recording medium reproducing device RAp2 and the disc-shaped recording medium 1 and the aging and aging due to actual use conditions;
After obtaining this, the process proceeds to step S361.

In step S361, step S359
After setting a linear velocity that is smaller by ΔLvm than the maximum linear velocity Lvm1 obtained in the above as the practical maximum linear velocity Lvm2, the process proceeds to step S363. This △ Lvm is the above △ N and △ R
Similarly, it corresponds to a safety factor set to ensure the actual reproduction operation in consideration of dimensional variations such as eccentricity of the disc-shaped recording medium 1. That is, △ Lv
m is equal to or greater than zero and is appropriately set according to the disk-shaped recording medium 1 itself and its mounting accuracy.

In step S363, the maximum linear velocity Lvm
After calculating the practical control switching point R7 ′ based on the following formula, the process proceeds to step S67. 18 and 19 show the characteristics at the time of CAV control and CLV control set as described above.

R7 ′ = Lvm2 / 2π · N (Rmin)

In step S365, after the CLV control is performed based on the current rotational speed N (Rmin), the process proceeds to step S67, and the CLV control based on the second embodiment is started. Note that the practical control switching point R7 ′, the maximum linear velocity Lvm2, and N (Rmi
n) is recorded in the reproduction drive control device 20 in the disc-shaped recording medium reproducing device RAP2, and the control switching point R2 and the initial rotation speed N (Rmi) when reproducing the disc-shaped recording medium 1 again.
n). However, in the actual use of the disc-shaped recording medium reproducing device RAp2 as described above, the performance of the signal processing circuit 17 can always be maximized under the use environment even if the maximum linear velocity Lvm is different every time. .
Further, it is possible to supply a device that is stable even in an operating environment and a change with time.

FIGS. 18 and 19 show the initial rotational speed N (Rmin) and the practical control initial rotational speed N thus obtained.
(Rmin), control switching point R7, and practical control switching point R
7 'is shown. The control switching point R7 is determined in step S
In 361, instead of the maximum linear velocity Lvm2, Lvm
1 shows a radius position when the position is obtained. The relationship between the radial position and the rotation speed in the present embodiment is represented by a solid line L7.
The relationship between the radial position and the rotational speed in the conventional CLV control is indicated by a broken line L. In FIG. 18, a portion surrounded by a circle C is a portion of the safety factor taken in steps S357 and S361 in FIG. 17, and FIG. 19 is an enlarged view of the portion. In this example, the case where the rotational speed is reduced while keeping the CAV control is described in detail. However, the rotational speed may be reduced after switching to the CLV control.

[0102]

[Embodiment 8] An eighth embodiment based on this embodiment will be described with reference to FIG. In the above-described first to seventh embodiments, the position of the disc-shaped recording medium reproducing apparatus which is currently being reproduced, that is, the position of the pickup 6, is detected based on the subcode information signal Sq in the reproduced signal SPU. However, the present embodiment provides a detection method that is not based on the subcode information signal Sq.

The disc-shaped recording medium reproducing apparatus R according to the present embodiment
Ap3 is a disk-shaped recording medium reproducing device RAp1 shown in FIG.
Is newly provided with a track cross detector 27,
On the basis of the tracking error signal Ste output from the servo controller 9, the pickup 6
Is generated to generate a track cross signal Stc indicating a state of traversing the signal track recorded in the data track. The reproduction drive control device 20 knows the position of the pickup 6 by counting the input track cross signal Stc.

That is, when the pickup 6 is reproducing the innermost circumference of the disc-shaped recording medium 1, the traverse motor 7
When the pickup 6 moves on the slider 8 in the outer circumferential direction, the output of the moving pickup 6 outputs a signal when it is on a signal track, but outputs a signal when it is between signal tracks. Can not do. Then, the tracking error signal Ste, which is the output of the moving pickup 6, is input to the track cross detector 27. The track cross detector 27 outputs a track cross signal Stc, which is indicated by a pulse indicating that the pickup 6 crosses the recording track, to the reproduction drive control device 20 based on the tracking error signal Ste. The reproduction drive control device 20 knows the number of signal tracks traversed by counting the number of pulses in the track cross signal Stc. From the number of traversed signal tracks, the position of the pickup 6 on the disc-shaped recording medium 1 is calculated by multiplying the number of traversed tracks by the signal track interval of the disc-shaped recording medium 1.

As described above, according to the present embodiment, the reproduction position of the pickup on the disk-shaped recording medium is determined by the reproduction signal Spu.
Without deciphering the address information Sq of the above, it is possible to provide an excellent means which can be calculated from the presence or absence of the output signal of the pickup when traversing the signal track of the disc-shaped recording medium.

[0106]

Ninth Embodiment A ninth embodiment based on the present embodiment will be described with reference to FIG. In this embodiment, as in the eighth embodiment, further means is provided for determining the position of the pickup 6 without being based on the subcode information signal Sq in the reproduction signal Spu. The disc-shaped recording medium reproducing device RAp4 according to the present embodiment has the same configuration as the disc-shaped recording medium reproducing device RAp1 shown in FIG. 1 except that the traverse motor 7 is replaced with a stepping motor 28 and the traverse following error of the output of the servo control device 9 is obtained. The signal Sts is input to the reproduction drive control device 20 instead of the traverse motor driver 19.

That is, the pickup 6 drives the stepping motor 28, which is a stepping type traverse motor, to read the recording signal of the disk-shaped recording medium 1 from the inner circumference to the outer circumference.
Move in the radial direction. The reproduction drive control device 20 drives the stepping motor 28 in the same manner as the traverse motor 7 according to the traverse forced feed signal Stm. When the pickup 6 is reproducing the innermost circumference of the disc-shaped recording medium 1,
A command to move the pickup 6 in the outer peripheral direction of the disc-shaped recording medium 1 is issued by the main controller 24 to the reproduction drive controller 2.
When an instruction is given to 0, the reproduction drive control device 20 outputs a traverse compulsory feed signal Stm to the stepping motor 28 to drive the pickup 6 to move on the slider 8 in the outer peripheral direction. Since the rotation amount of the stepping motor 28 is determined by the number of drive input signals, the pickup 6 moves in the outer peripheral direction by an amount corresponding to the movement instruction of the reproduction drive control device 20 on a one-to-one basis. That is, the system microcomputer 18 can know the moving distance of the pickup 6 from the instruction given to the stepping type traverse motor 21.

As described above, according to this embodiment, the reproduction position of the pickup on the disk-shaped recording medium is calculated from the drive signal of the stepping motor for driving the pickup without decoding the address information of the reproduction signal. And provide an excellent means of performing such operations.

[0109]

Embodiment 10 Referring to FIG. 22, a tenth embodiment based on the present embodiment will be described. In this embodiment,
As in the eighth and ninth embodiments, the pickup 6 is not based on the subcode information signal Sq in the reproduction signal Spu.
Provides a means to determine the position of The disc-shaped recording medium reproducing device RAp5 according to the present embodiment has a switch 29 for knowing the position of the pickup 6 newly provided on the slider 8 in the configuration of the disc-shaped recording medium reproducing device RAp1 shown in FIG. . A switching signal Sw indicating the open / close state of the switch 29 is input to the reproduction drive control device 20.

In the disc-shaped recording medium reproducing device Rap5 thus configured, when the pickup 6 is reproducing the innermost periphery of the disc-shaped recording medium 1, an instruction to read the outer periphery is issued from the main controller 24. When it comes out, the pickup 6 moves on the slider 8 in the outer peripheral direction by the drive of the traverse motor 7. When the pickup 6 reaches the position of the switch 23 during the movement, the state of the switch 29 changes from open to closed. This change, that is, the fact that the cup 6 has reached the position of the switch 29, can be detected by the reproduction drive control device 20 based on the switching signal Sw.

As described above, according to the present embodiment, the reproduction position of the pickup 6 on the disk-shaped recording medium 1 can be determined without decoding the address information of the reproduction signal.
It is possible to provide an excellent means capable of detecting from the open / closed state of the switch 23 provided on the slider 8 which moves. Although a mechanical switch has been described as the reproducing position detecting element, it goes without saying that the same effect can be obtained by using a non-contact type switch such as an optical sensor or a magnetic sensor. Furthermore, in the description of each of the above embodiments, a description has been given as a group of blocks of circuits. However, a part or all of the circuit operations may be operated on a microcomputer program.

Next, with reference to FIG. 23, the relationship between the mechanical system factor and the signal processing factor with respect to the maximum allowable rotation speed in the disc-shaped recording medium reproducing apparatus will be described. In the figure,
The vertical axis represents the rotational speed N, the horizontal axis represents the radial position R on the disk-shaped recording medium, the straight line Lm represents the upper limit of the allowable rotational speed of the driving mechanism system represented by the spindle motor 4, and the curve Ls represents the decoder 17.
The upper limit of the permissible number of rotations of the signal processing system represented by is shown. Note that the maximum rotation speed of the drive mechanism system is not restricted by the radial position R, but the allowable rotation speed Nma of the signal processing system.
Since x is equivalent to the maximum linear velocity, it is already proportional to 1 / 2πR as described above.

To be precise, the maximum allowable rotation speed Nmax of the drive mechanism is not constant. As an example of the cause,
In addition, the servo control is invalidated due to shaking that occurs during rotation due to the eccentricity of the disc-shaped recording medium, and the number of revolutions of the disc-shaped recording medium must be reduced for recording and reproducing information. There is variation in the manufacturing accuracy of Next, there is a temporal change such as a decrease in the number of revolutions due to poor lubrication due to running out of oil of the spindle motor or the like. Further, there are thermal factors such as a decrease in torque due to heat generated by the spindle motor and a deterioration in performance of the spindle motor driver, and a change in use environment.

Maximum allowable rotation speed Nma in the signal processing system
The limiting factor of x (Rmax) is a fluctuation such as an upper limit of the operation frequency of the signal processing circuit itself or a decrease in the operation speed due to heat generation. Therefore, when manufacturing a disc-shaped recording medium reproducing apparatus, the maximum allowable rotation speed Nmax is reduced by a safety factor that is set as a margin with the maximum fluctuation amount of these limiting factors as a margin. In other words, the inherent performance of the device is wasted.
Therefore, the present invention provides a disk-shaped recording medium reproducing apparatus that can exhibit the maximum performance by minimizing the margin for such a limiting factor or controlling the margin freely according to the actual use situation. is there. 24 and 2
A description will be given with reference to FIGS.

First, referring to the flowchart of FIG. 24, the maximum permissible rotational speed Nmax (Rm) of the disc-shaped recording medium reproducing device at an arbitrary radial position on the disc-shaped recording medium.
The detection operation of ax) will be described. First, step S4
01 is a disc-shaped recording medium reproducing apparatus R mounted on a disc-shaped recording medium.
When the disk-shaped recording medium 1 is mounted on the Ap, the spindle motor 4 is driven in step S403, and the disk-shaped recording medium 1 starts rotating. As a result, as the time elapses, the rotation speed of the disc-shaped recording medium 1 increases, and after reading the TOC information in step S405, the reproduction of the data recorded on the disc-shaped recording medium 1 is started based on the TOC information. I do.

At step S407, decoding abnormal signal Sn
Based on g, it is determined whether the current linear velocity is equal to or less than the maximum linear velocity Lvm. If Sng is 0, the process proceeds to step S409, and the current rotational speed N is stored as the current rotational speed Np. Then, in step S410, the specified rotation speed Nc is calculated by adding the aforementioned predetermined rotation speed △ N to the current rotation speed Np. In step S413, after the spindle motor 4 is rotated at the designated rotation speed Nc, the process proceeds to step S407.
The determination is repeated as to whether the speed at which the rotation speed has been increased by ΔN from the previous time is equal to or lower than the maximum linear speed Lvm.

If it is determined in step S407 that the current rotational speed N (Nc) is greater than the maximum linear speed Lvm, the previous current rotational speed Np recorded in step S409 is used. Is the maximum allowable rotation speed Nmax
(Rmax). Then, the above-described CLV control and CAV control are performed based on the maximum allowable rotation speed Nmax (Rmax).

As described above, by gradually increasing the rotation speed of the disc-shaped recording medium 1, the combination of the disc-shaped recording medium reproducing device Rap, the disc-shaped recording medium 1, and the use environment can be improved. The actual maximum linear velocity Lvm and the maximum allowable rotation speed Nmax (Rmax) are detected, and can be used as reference speeds for rotation control of the disc-shaped recording medium reproducing device RAP. Further, if NO is determined in the above step S407, the current rotational speed Np detected immediately before in step S409 is directly used as the maximum allowable rotational speed Nmax (Rm
ax), but when the disc-shaped recording medium has a large run-out or the like, it is conceivable that the immediately preceding rotation speed Np is too fast. In response to this, the aforementioned step S40
The problem can be solved by providing a routine including steps similar to steps 9, S411, and S413. That is, in this routine, contrary to the processing in step S411,
The spindle motor 4 is rotated at a speed obtained by reducing the current rotational speed Np by ΔN, and it is confirmed that the decode monitor signal Sng becomes 0. In addition, such routines
Performing desired control in combination with the above description of the method and apparatus according to the present invention using various drawings is sufficiently disclosed by a person skilled in the art, and further description will be omitted.

A typical example of the operation of the disc-shaped recording medium reproducing apparatus RAp according to the present invention will be briefly described below with reference to FIGS. 25, 26, 27, and 28. The relationship between the rotation speed N and the control switching point R optimized by the disc-shaped recording medium reproducing device RAp based on the seventh embodiment described with reference to FIGS. 18 and 19 is shown by a solid line L7 in FIG. The relationship between N and time t is shown in FIG. 26 by a solid line L7t.

As shown in FIG. 25, in the innermost peripheral portion Rmin, once the rotational speed N of the disc-shaped recording medium 1 is increased, N (Rmi) which is the upper limit of the rotational speed of the motor capable of signal processing.
Know n). CAV control is started with the upper limit rotation speed N (Rmin) as an initial rotation speed. Since the overflow of the decoder 17 is detected at the radial position R, the immediately preceding radial position R
Switch to CLV control at 7 '.

Referring to FIG. 26, the driving of the spindle motor 4 is started at time t0, and the disc-shaped recording medium 1 is started.
The speed of rotation increases rapidly. At time t1, it is possible to determine the presence / absence of overflow due to the decoding error signal Sng, exceeding the minimum operation speed of the signal processing system. At time t2,
It is detected that the decoding error signal Sng has become 1 and the rotation speed has exceeded the maximum allowable rotation speed Nmax, and the drive rotation speed Nc of the spindle motor 4 is slightly reduced. At time t3, the decoding error signal Sng becomes 0 again. The upper limit rotational speed N
(Rmin) is obtained. Thereafter, CAV control is performed at the upper limit rotational speed N (Rmin) until time t4, and the radial position R
At 7, the decoding error signal Sng becomes 1 again. Then
The rotation speed Nc is slightly reduced, and the CLV control is performed from time t5 when the decoding abnormality signal Sng becomes 0.

Once the upper limit rotation speed N (Rmin) and the control switching limit position R7 are detected, N (Rmi) which is smaller by △ N and △ R respectively as the margin from the next time.
n) ′ and R7 ′ can be used as the upper limit rotational speed and the control switching limit point. Also, the processing capacity L of the signal processing system
If s is significantly lower than the rotational speed upper limit Lm of the drive mechanism, R7 '(R7) will be equal to the innermost peripheral portion Rmin, and the entire area of the disc-shaped recording medium 1 is subjected to CLV control. In this manner, the highest performance of the disc-shaped recording medium reproducing device RAP can be obtained, and the decoding error signal Sn can be obtained.
Since the signal processing state is constantly monitored by g, even when the device is deteriorated due to heat generation or aging, the highest performance in that state can be secured.

Similarly, when the disc-shaped recording medium reproducing apparatus RAp according to the present invention is optimized for reproducing a disc-shaped recording medium in which TOC information is recorded on the innermost periphery, as represented by a CD-ROM. FIG. 2 shows the relationship between the rotational speed N and the control switching point R.
7 is shown by a solid line L7 ', and the relationship between the rotation speed N and the time t is shown by a solid line L7t' in FIG. First, the rotation starts at time t0, exceeds the minimum linear velocity of the signal processing system at time t1, and when the linear velocity at the innermost peripheral portion Rmin reaches a predetermined value at time t1a, the rotation speed at this time N (TOC) is taken as the initial speed and is reflected in the CLV control.
When the OC information is started and the reading of the TOC is completed at time t1b, the rotation of the spindle motor 4 is accelerated again,
The maximum allowable rotation speed Nmax is obtained. From time t2, FIG.
6 is the same as that described in FIG. At this time, the relationship between the rotational speed N and the radial position R is, as shown in FIG.
Necessary information can be quickly read from each area by immediately switching to the appropriate rotation speed in the AV area and the CLV area.

[0124]

As is apparent from the above description, according to the present invention, the spindle motor is driven so that the linear velocity of the read signal is constant according to the read position of the pickup, and the disk-shaped motor is driven at another read position. By immediately switching the control of the spindle motor so that the rotation speed of the recording medium becomes constant, it is not necessary to change the rotation speed of the disc-shaped recording medium when the reading position of the pickup moves, or The amount of change can be reduced, and the recording signal of the disk-shaped recording medium can be quickly read.

Furthermore, when the pickup moves from the inner circumference to the outer circumference, the spindle motor is initially controlled so that the linear velocity of the read signal is constant, and the spindle motor is controlled from an arbitrary predetermined position on the way to the outermost circumference. In the range, by immediately switching the control of the spindle motor so that the rotation speed of the disk-shaped recording medium becomes constant, when the reading position of the pickup is moved, it is not necessary to change the rotation speed of the disk-shaped recording medium, Alternatively, the amount of change in the number of revolutions can be reduced, and the recording signal on the disk-shaped recording medium can be quickly read.

When the pickup moves from the inner circumference to the outer circumference, the spindle motor is initially controlled so that the linear velocity of the read signal is constant. When the rotation speed that gives the maximum linear velocity that can be processed by the processing circuit is reached, the rotation control of the spindle motor is immediately switched so that the rotation speed becomes constant at the rotation speed from the position where the rotation speed is reached to the outermost periphery. When the reading position moves,
It is not necessary to change the number of revolutions of the disc-shaped recording medium, or the amount of change in the number of revolutions can be reduced, and the recording signal of the disc-shaped recording medium can be quickly read.

Further, when the pickup moves from the inner circumference to the outer circumference, the spindle motor is initially controlled so that the linear velocity of the read signal is constant, and the rotational speed of the disk-shaped recording medium is set at the outermost circumference of the recording area. When the number of revolutions giving the maximum linear velocity that can be processed by the signal processing circuit is reached, the spindle is maintained at the same number of revolutions from the position where the number of revolutions is reached to the outermost periphery of the recording area of the disc-shaped recording medium. By immediately switching the rotation control of the motor, it is not necessary to change the rotation speed of the disk-shaped recording medium when the reading position of the pickup moves, or the amount of change in the rotation speed can be reduced, and the disk-shaped recording medium can be reduced. The recording signal of the recording medium can be quickly read.

Further, when the pickup moves from the inner circumference to the outer circumference, the spindle motor is initially controlled so that the linear velocity of the read signal is constant, and the rotational speed of the disk-shaped recording medium is reproduced at that time. At the outermost circumference of the use area of the disc-shaped recording medium, when the rotation speed that gives the maximum linear velocity that can be processed by the processing circuit is reached, the rotation speed becomes constant from the position where the rotation speed is reached to the outermost circumference. By immediately switching the rotation control of the spindle motor, it is not necessary to change the rotation speed of the disk-shaped recording medium when the reading position of the pickup moves, or the amount of change in the rotation speed can be reduced. It is possible to quickly read out the recording signal of the shape recording medium.

Further, the spindle motor is driven so that the linear velocity of the read signal is constant depending on the read position of the pickup, and the spindle motor is controlled so that the rotational speed of the disk-shaped recording medium is constant at another read position. By immediately switching the control, when the reading position of the pickup moves, it is not necessary to change the rotation speed of the disk-shaped recording medium or the amount of change in the rotation speed can be reduced, and the disk-shaped recording medium can be changed. The recorded signal can be read out quickly.

Further, the spindle motor is driven so that the linear velocity of the read signal is constant depending on the read position of the pickup, and the spindle motor is controlled such that the rotational speed of the disk-shaped recording medium is constant at another read position. By immediately switching the control, it is not necessary to change the rotation speed of the disk-shaped recording medium when the reading position of the pickup moves, or the amount of change in the rotation speed can be further reduced, and the disk-shaped recording medium can be changed. The recording signal can be read out quickly. Also, if the speed of the reproduced signal reaches a position exceeding the maximum speed that can be decoded by the disc-shaped recording medium reproducing device while controlling the rotation speed of the disc-shaped recording medium to be constant, the disc-shaped recording medium is immediately turned on. The control can be switched immediately so that the rotation of the recording medium rotates at a constant linear velocity.

Further, when the pickup moves in the radial direction of the disk-shaped recording medium, the number of tracks of the traversed signal is measured, and the position currently being reproduced is calculated from the number of tracks of the signal traversed by the pickup. It is possible to calculate the rotation speed of the disc-shaped recording medium without reading the sub-code of the signal.

Furthermore, it is possible to calculate the position currently being reproduced from the number of times of driving of the stepping motor for moving the pickup in the radial direction of the disk-shaped recording medium, and to calculate the position currently reproduced without reading the sub-code of the signal. I can do it.

Further, by detecting that the pickup moving in the radial direction of the disc-shaped recording medium is at a predetermined position arbitrarily determined, the position currently being reproduced can be determined without reading the sub-code of the signal. Can be calculated.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a structure of a disc-shaped recording medium reproducing device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of CLV-CAV control according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing a detailed operation in the CLV-CAV control shown in FIG.

FIG. 4 is an explanatory diagram of CAV-CLV control according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing a detailed operation in the CAV-CLV control shown in FIG.

FIG. 6 is an explanatory diagram of CLV-CAV control according to a third embodiment of the present invention.

FIG. 7 is an explanatory diagram of a recording area of a disc-shaped recording medium.

8 is a flowchart showing a detailed operation in the CLV-CAV control shown in FIG.

FIG. 9 is an explanatory diagram of CLV-CAV control according to a fourth embodiment of the present invention.

10 is a flowchart showing a detailed operation in the CLV-CAV control shown in FIG.

FIG. 11 shows a CLV-CAV according to a fifth embodiment of the present invention.
FIG. 4 is an explanatory diagram of control.

12 is a flowchart showing a detailed operation in the CLV-CAV control shown in FIG.

FIG. 13 shows a CAV-CLV according to a sixth embodiment of the present invention.
FIG. 4 is an explanatory diagram of control.

14 is a flowchart showing an operation of optimizing a radial position in the CAV-CLV control shown in FIG.

FIG. 15 is a flowchart showing an operation of optimizing the maximum rotation speed in the CAV-CLV control shown in FIG.

FIG. 16 is a block diagram showing a structure of a disc-shaped recording medium reproducing device according to a seventh embodiment of the present invention.

17 is a flowchart showing the operation of CAV-CLV control by the disc-shaped recording medium reproducing device shown in FIG.

18 is an explanatory diagram showing a relationship between a maximum rotation speed and a practical rotation speed in the CAV-CLV control shown in FIG. 16, and a relationship between a limit control switching point and a practical control switching point.

19 is an enlarged view of a main part of FIG. 18;

FIG. 20 is a block diagram showing a structure of a disc-shaped recording medium reproducing device according to an eighth embodiment of the present invention.

FIG. 21 is a block diagram showing a structure of a disc-shaped recording medium reproducing device according to a ninth embodiment of the present invention.

FIG. 22 is a block diagram showing a structure of a disc-shaped recording medium reproducing device according to a tenth embodiment of the present invention.

FIG. 23 is an explanatory diagram of a relationship between a mechanical system factor and a signal processing factor with respect to a maximum allowable rotation speed in a disc-shaped recording medium reproducing device.

FIG. 24 is a flowchart showing a method of obtaining a maximum allowable rotation speed Nmax (Rmax) at an arbitrary radial position on a disk-shaped recording medium by the disk-shaped recording medium reproducing apparatus according to the present invention.

FIG. 25 is an explanatory diagram of a relationship between a rotational speed N and a control switching point R optimized by a disc-shaped recording medium reproducing device RAp according to a seventh embodiment of the present invention.

FIG. 26 is an explanatory diagram showing the relationship between the rotation speed N and the time t optimized by the disc-shaped recording medium reproducing device RAp according to the seventh embodiment of the present invention.

FIG. 27 is a disc-shaped recording medium reproducing apparatus RA according to the present invention.
The rotation speed N and the control switching point R when p is optimized for the reproduction of a disc-shaped recording medium having TOC information recorded on the innermost periphery.
It is explanatory drawing which shows the relationship.

FIG. 28 is a disc-shaped recording medium reproducing apparatus RA according to the present invention.
FIG. 9 is an explanatory diagram showing the relationship between the rotation speed N and time t when p is optimized for reproduction of a disc-shaped recording medium having TOC information recorded on the innermost periphery.

FIG. 29 is a block diagram showing the structure of a conventional disk-shaped recording medium reproducing device.

30 is an explanatory diagram of CLV playback control by the conventional disc-shaped recording medium playback device shown in FIG. 29.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Disc-shaped recording medium 2 Turntable 3 Clamper 4 Spindle motor 5 Rotating shaft 6 Pickup 7 Traverse motor 8 Slider 9 Servo control device 10 Clock separator 11 Reference clock generator 12 CLV error detector 13 Frequency generator 14 Reference frequency generator Reference Signs List 15 CAV error detector 16 Drive control switching unit 17 Decoder 18 Spindle motor driver 19 Traverse motor driver 19 20 Reproduction drive control device 20 Reproduction drive control device 21 CLV control device 22 CAV control unit 24 Main control device

Claims (12)

[Claims] 1. A disk-shaped recording medium (1) on which information is recorded at a constant linear velocity on a recording track extending around a center of a recording surface while rotating at a predetermined speed (N).
A disc-shaped recording medium reproducing device (RAp) for reading information from the recording track, wherein the recording track is scanned and a first reproduction signal (Spu, S
PU, Ste), and a first rotation control for rotating the disc-shaped recording medium (1) at a predetermined linear velocity (CLV) based on the reproduction signal (Spu, SPU). Means (21); second rotation control means (22) for rotating the disc-shaped recording medium (1) at a predetermined rotation speed (CAV); and the second rotation control means based on the position of the pickup means (6). One rotation control means (21) and the second rotation control means (22)
Rotation control switching means (2
0, 16), a disc-shaped recording medium reproducing apparatus (RAp). 2. The disk-shaped recording medium reproducing device (RAp1) according to claim 1, further comprising: a reproducing signal (Spu, SP).
U) a first position detecting means (S) for detecting the position of the pickup (6) from the subcode information (Sq) included in
5. A disc-shaped recording medium reproducing apparatus (RAp), comprising: (S7). 3. The disc-shaped recording medium reproducing apparatus (RAp2) according to claim 1, further comprising: decoding the first reproduced signal (SPU) to generate a second reproduced signal (Sd, Sst). ) For generating signal processing means (1)
7), based on the second reproduced signal (Sst), the signal processing means (17) generates a monitor signal (Sng) indicating whether the decoding processing state of the first reproduced signal (SPU) is normal or not. And the monitoring signal (Sng) indicates that the decoding processing state of the signal processing means (17) is abnormal, the signal processing means (1)
A disc-shaped recording medium reproducing apparatus (RAp2), comprising: a reproducing control means (20) for detecting that the data rate (7) exceeds a maximum data rate (Vm) that can be processed. 4. The disc-shaped recording medium reproducing apparatus (RAp) according to claim 3, further comprising: said reproducing control means (20).
Comprises a means (S359) for calculating a maximum linear velocity (Lvm) corresponding to the maximum data rate (Vm), the disc-shaped recording medium reproducing apparatus (RAp). 5. The disc-shaped recording medium reproducing apparatus (RAp) according to claim 4, further comprising: said reproducing control means (20).
Is the linear velocity (Lv) at an arbitrary radial position (R).
(S1) means for calculating the number of revolutions (N (R)) that gives
05), a disc-shaped recording medium reproducing apparatus (RAp). 6. The disc-shaped recording medium reproducing apparatus (RAp1) according to claim 5, wherein said rotation control switching means (21).
The first rotation when the pickup means (6) is located on the inner peripheral side of a first switching point (R1) located on a first predetermined radius (R2) of the disc-shaped recording medium (1). The control means (21) is enabled, and the second rotation control means (22) is enabled when the pickup means (6) is on the outer peripheral side of the first switching point (R1). Disc-shaped recording medium reproducing device (RAp1). 7. The disc-shaped recording medium reproducing apparatus (RAp1) according to claim 6, wherein a rotation speed (N (R1)) corresponding to said predetermined linear velocity at said first switching point (R1). )
Is the outermost peripheral portion (Rma) of the recording surface of the disc-shaped recording medium (1).
x) The disc-shaped recording medium reproducing apparatus (RAp1), wherein x corresponds to the maximum linear velocity (Lvm). 8. The disc-shaped recording medium reproducing apparatus (RAp2) according to claim 5, wherein said rotation control switching means (21).
Means that the pickup means (6) is located on the inner peripheral side of a second switching point (R2) located on a second predetermined radius (R2) of the disc-shaped recording medium (1). The rotation control means (22) is enabled, and the first rotation control means (21) is enabled when the pickup means (6) is located on the outer peripheral side of the second switching point (R2). Disc-shaped recording medium reproducing device (RAp2). 9. The disc-shaped recording medium reproducing apparatus (RAp2) according to claim 8, wherein the linear velocity corresponding to the predetermined rotation speed at the first switching point (R2) is the maximum linear velocity. (Lvm), a disc-shaped recording medium reproducing apparatus (RAp1). 10. The disc-shaped recording medium reproducing apparatus (RAp3) according to claim 1, further comprising: the reproduction signal (Stp).
e) generating a track number signal (Stc) indicating the number of recording tracks traversed by the pickup means (6), and the pickup based on the track number signal (Stc). And a second position detecting means (20) for detecting a radial position (R) of the means (6). 11. The disc-shaped recording medium reproducing device (RAp4) according to claim 1, wherein the disc-shaped recording medium (1).
A stepping motor (28) for moving the pickup means (6) in the radial direction, and a third position detection for detecting a radial position (R) of the pickup means (6) from the number of times the stepping motor (28) is driven. A disc-shaped recording medium reproducing apparatus (RAp3), characterized by having means (20). 12. The disc-shaped recording medium reproducing apparatus (RAp5) according to claim 1, wherein said pickup means (6) is switched by a switch means (29) for detecting that it is at an arbitrary predetermined position. A disc-shaped recording medium reproducing apparatus (RAp) having a fourth position detecting means (20) for detecting a radial position (R) of the pickup means (6);
5).