JPH07244942A - Device for reproducing optical disk and method of controlling it - Google Patents

Abstract

PURPOSE:To minimize the time required for again reading immediately after zone switching by repeating one track jump until the number of revolution of a disk arrives at a prescribed number of revolution after zone switching and ending the track jump at the time of arriving at the prescribed number of revolution. CONSTITUTION:When the zone switching is detected by a zone detection circuit 27 while reproducing the disk, the circuit 27 outputs the detection signal to a one track jump generation circuit 34. When the circuit 34 receives the zone switching detection signal, the circuit 34 impresses a track jump pulse to a drive circuit 30 in addition to a loop of a tracking error, and moves an optical pickup 21 in the direction of returning it by one track. For the stand-by time, the circuit 34 generates the track jump pulse, and makes so that the optical pickup 21 repeats one track jump. Thereafter, when the number of revolution of the disk arrives at the prescribed number of revolution and is locked, a locking signal is outputted from a motor servo circuit 31 to the circuit 34.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk reproducing apparatus, and more particularly to an MCLV (Modified Constant Linear Vel
and a control method thereof.

[0002]

2. Description of the Related Art An MCLV type disc is shown in FIG.
As shown in, the entire recording area is divided into a plurality of zones each including a predetermined number of adjacent tracks. As shown in FIG. 9, when signal recording / reproduction is performed on a disc of the MCLV system by gradually decreasing the disc rotation speed for each zone from the inner circumference side to the outer circumference side of the disc, the sector length of each zone is As shown in FIG. 10, the length of each track gradually increases from the inner circumference side to the outer circumference side. That is, the recording linear density in each zone continuously decreases from the inner circumference side to the outer circumference side of the disk.

When the reproduction is advanced from the inner side to the outer side of the disc, the disc rotation speed gradually reaches a predetermined rotation speed through a transitional state as shown in FIG. 11 at the time of zone switching. Therefore, as shown in FIG. 12, the frequency (data rate) of the data on the disk also rapidly increases immediately after the zone switching, and becomes constant after the disk rotation speed reaches a predetermined rotation speed.

When reproducing an MCLV disc as described above, the data rate changes with the abrupt change in the disc rotation speed immediately after the zone switching, so that the data of the first track after the zone switching is correctly corrected. It becomes impossible to read.

Conventionally, there is the following optical disk reproducing apparatus constructed in view of such a situation. FIG. 13 shows the configuration of this optical disk reproducing apparatus.

In this optical disk reproducing apparatus, reproduction is performed as follows. First, the data on the optical disk D is read by the optical pickup 1, the reproduction signal thereof is amplified by the RF amplifier 2, and then the waveform equalizer 3 equalizes the waveform. Next, the output reproduction signal of the waveform equalizer 3 is binarized by the data slicer 4, and then sent to the PLL circuit 5 and the latch circuit 6. The PLL circuit 5 generates a reproduction clock phase-synchronized with the binarized data, and supplies the reproduction clock signal to the latch circuit 6 and the track jump generation circuit 7. The latch circuit 6 latches the binarized data at the timing of the rising edge of the reproduction clock signal and transfers the reproduction data to the processing unit in the subsequent stage. On the other hand, the output of the RF amplifier 2 is a tracking error detection circuit (hereinafter referred to as TE detection circuit).
It is also output to 8. The TE detection circuit 8 detects a tracking error from the output of the RF amplifier 2 and outputs the tracking error detection signal to the drive circuit 10 through the loop filter 9 when the tracking error is detected. The drive circuit 10 drives a feed mechanism (not shown) of the optical pickup 1 based on the tracking error detection signal to perform tracking control. Reference numeral 11 is a motor servo circuit for controlling the rotation speed of the disk D. The control of the disk rotation speed by the motor servo circuit 11 is performed based on a signal obtained by dividing the frequency of the synchronizing signal component extracted from the output of the RF amplifier 2 by the frequency dividing circuit 12. Further, 13 is a disk motor which is driven under the control of the motor servo circuit 11, and 14 is a zone detection circuit which detects zone switching from the reproduction data obtained through the latch circuit 6.

In this optical disk reproducing apparatus, the following two methods are considered as measures for suppressing the large fluctuation of the reproduction data rate immediately after the zone switching. One is a system in which the range of the PLL circuit 5 is widened for a certain period of time from the time when the zone detection circuit 14 detects the zone switching. However, if the range of the PLL circuit 5 is widened, the time from the occurrence of zone switching to the arrival of the desired reproduction data rate is shortened, but on the other hand, it becomes vulnerable to external disturbances and the data may not be reproduced correctly. There is.

In another method, the frequency of the clock generated by the PLL circuit 5 is monitored by the track jump generation circuit 7 and a track jump pulse is supplied to the drive circuit 10 when the clock frequency greatly deviates from an appropriate value. This is a method in which the optical pickup 1 is jumped to the previous track. That is, this is to retry the signal reading from the area immediately after the zone switching in which the data could not be correctly reproduced. In this method, it is necessary to make the optical pickup 1 jump two tracks or more in order to ensure that the disk rotation speed reaches a predetermined rotation speed at the time of starting the reading again from the area immediately after the zone switching. is there. In other words, with this method, there is no guarantee that the disk rotation speed has reached the predetermined rotation speed at the time when the reading from the area immediately after zone switching is started again. This is ensured by increasing the number, and the success rate of reading is increased again. However, on the other hand, there is a problem that the seek time of the optical pickup 1 for reading again is long and the overall loss time is large.

[0009]

As described above, in the conventional optical disk reproducing apparatus, the range of the PLL circuit is widened at the time of zone switching, or the area that could not be correctly reproduced is read again, so that reproduction between consecutive zones is performed. However, the former method has a problem in that the influence of disturbance increases, and the latter method has a problem that a seek time of two tracks or more including a time margin is required for each read.

The present invention is intended to solve such a problem and can shorten the time required for re-reading after zone switching, and in addition, correctly reproduce from the first data after zone switching. It is an object of the present invention to provide an optical disk reproducing device capable of performing the above.

Further, according to the present invention, it is possible to shorten the time required for re-reading after zone switching,
In addition, another object of the present invention is to provide a control method of an optical disk reproducing device that can correctly reproduce the first data after the zone switching.

[0012]

In order to achieve the above-mentioned object, an optical disk reproducing apparatus according to a first aspect of the present invention divides an entire recording area into zones each consisting of a plurality of adjacent tracks and records in each zone. In an optical disc reproducing apparatus for reproducing an optical disc whose linear density continuously changes at a constant reproduction data rate over each zone, an optical pickup for reading a recording signal of the optical disc and a zone for reading the signal by the optical pickup are switched. When the zone switching is detected by the detecting means for detecting and the detecting means, the optical pickup is caused to perform a track jump in the direction of returning one track almost every rotation cycle of the optical disk, and the disk rotational speed reaches a predetermined rotational speed after the zone switching. Control means to control to end the track jump when It is characterized in that Bei.

In order to achieve the above-mentioned object, the optical disk reproducing apparatus according to a second aspect of the present invention divides the entire recording area into zones each consisting of a plurality of adjacent tracks, and the signals are recorded at different linear recording densities for each zone. In an optical disc reproducing apparatus for reproducing a recorded optical disc at a constant reproduction data rate over each zone, an optical pickup for reading a recording signal of the optical disc, and a pickup feeding mechanism for moving the optical pickup in the radial direction of the optical disc,
A detection unit that detects a zone change in which a signal is read by the optical pickup, and a pulse signal that causes the optical pickup to make a track jump in the direction of returning one track when the change of the zone is detected by the detection unit, substantially rotates the optical disk. The track jump pulse generating means which is generated for each cycle and is supplied to the pickup feed mechanism and the disk rotational speed during the track jump period are monitored, and when the disk rotational speed reaches a predetermined rotational speed after the zone switching, the track jump is performed. And a control means for outputting a request signal to the pulse generation means so as to terminate the generation of the pulse signal. Further, in order to achieve the above-mentioned object, the control method of the optical disk reproducing apparatus according to claim 6 divides the entire recording area into zones each consisting of a plurality of adjacent tracks, and records a signal with a different linear recording density for each zone. An optical disc reproducing apparatus for reproducing a recorded optical disc at a constant reproduction data rate over each zone, a step of detecting a zone change in which a signal is read by an optical pickup, and an optical pickup when the zone change is detected. Track jumping in the direction of returning one track approximately every rotation cycle of the optical disk, and ending the track jump when the disk rotational speed reaches a predetermined rotational speed after the zone switching. Is.

Furthermore, in order to achieve the above-mentioned object, the control method of the optical disk reproducing apparatus according to a seventh aspect of the present invention is such that the entire recording area is divided into zones each consisting of a plurality of adjacent tracks, and different line recording is performed for each zone. An optical disc reproducing apparatus for reproducing an optical disc having a signal recorded at a density at a constant reproduction data rate over each zone, wherein an optical pickup for reading a recording signal of the optical disc and the optical pickup are moved in the radial direction of the optical disc. In an optical disc reproducing device equipped with a pickup feeding mechanism,
A step of detecting a zone change in which a signal is read by an optical pickup, and a pulse signal for causing the optical pickup to make a track jump in a direction of returning one track when the zone change is detected is picked up almost every rotation cycle of the optical disc. The step of supplying to the feed mechanism and the step of monitoring the disk rotation speed during the track jump period and ending the supply of the pulse signal to the pickup feed mechanism when the disk rotation speed reaches a predetermined rotation speed after the zone switching. It is characterized by having.

[0015]

According to another aspect of the present invention, in the optical disk reproducing apparatus according to the first aspect, the control means operates at the same position in the zone switching area from the time the zone switching is detected until the disk rotational speed reaches a predetermined rotational speed after the zone switching. One track jump is repeated in the returning direction of the optical pickup, and when the disk rotation speed reaches the predetermined rotation speed after the zone switching, the track jump is ended. Therefore, after the last track jump, the first data after the zone switching is started. It can be played correctly.

In the optical disc reproducing apparatus according to the second aspect,
The track jump pulse generating means jumps one track in the returning direction of the optical pickup at the same position in the zone switching area from the detection of the zone switching until the disc rotational speed reaches the predetermined rotational speed after the zone switching. A track jump pulse signal is generated and supplied to the pickup feed mechanism so as to repeat. When the disk rotation speed reaches the predetermined rotation speed after the zone switching, the control means controls the end of the generation of the track jump pulse signal and the end of the track jump of the optical pickup, so that the final After the track jump, correct reproduction can be performed from the first data after the zone switching.

According to a sixth aspect of the present invention, there is provided a method for controlling an optical disk reproducing apparatus, wherein a zone switching region is detected at the same position from the time when the zone switching is detected until the disc rotational speed reaches a predetermined number after the zone switching. Repeated one-track jump in the direction to return the pickup,
When the disk rotation speed reaches the predetermined rotation speed after the zone switching, the track jump is ended, so that after the last track jump, the correct reproduction can be performed from the first data after the zone switching.

According to a seventh aspect of the present invention, there is provided a method for controlling an optical disk reproducing apparatus, wherein a zone of a zone switching area is read at the same position from the time when the zone switching is detected until the number of disk rotations reaches a predetermined number after the zone switching. A track jump pulse signal is generated almost every rotation cycle of the optical disc so as to repeat a one-track jump in the return direction of the pickup and is supplied to the pickup feed mechanism, and the disc rotation speed reaches a predetermined rotation speed after zone switching. Then, by ending the generation of the track jump pulse signal and ending the track jump of the optical pickup, it is possible to correctly reproduce from the first data after the zone switching.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an optical disk reproducing apparatus according to an embodiment of the present invention. In the figure, reference numeral 21 is an optical pickup for reading data on the optical disc D. The signal read by the optical pickup 21 is amplified by the RF amplifier 22 and then waveform-equalized by the waveform equalizer 23. The output reproduction signal of the waveform equalizer 23 is binarized by the data slicer 24 and then sent to the PLL circuit 25 and the latch circuit 26. PLL circuit 25
Generates a reproduction clock phase-synchronized with the binarized data and supplies the reproduction clock signal to the latch circuit 26. The latch circuit 26 latches the binarized data at the timing of the rising edge of the reproduction clock signal, and reproduces the reproduction data at the subsequent processing unit and zone detection circuit 27.
Transfer to. The zone detection circuit 27 detects zone switching from the reproduction data obtained through the latch circuit 26,
The detection signal will be described later in a 1-track jump generation circuit 3
Output to 4.

On the other hand, the output of the RF amplifier 22 is also output to a tracking error detection circuit (hereinafter referred to as TE detection circuit) 28. The TE detection circuit 28 detects a tracking error from the output of the RF amplifier 22, and when the tracking error is detected, the tracking error detection signal is output to the drive circuit 30 through the loop filter 29.
The drive circuit 30 controls the tracking of the optical pickup 21 based on the tracking error detection signal. Reference numeral 31 is a motor servo circuit for controlling the rotation speed of the disk D. The control of the disk rotation speed by the motor servo circuit 31 is performed based on a signal obtained by dividing the synchronizing signal component extracted from the output of the RF amplifier 22 by the frequency dividing circuit 32. The motor servo circuit 31 sends a lock signal 1 to be described later when the disk rotation speed after zone switching reaches (locks) a predetermined rotation speed unique to the zone.
It has a function of sending to the track jump generation circuit. Further, 33 is a disk motor driven under the control of the motor servo circuit 31. Reference numeral 34 is a 1-track jump generation circuit. When the zone switching detection signal from the zone detection circuit 27 is input, the 1-track jump generation circuit 34 applies a track jump pulse to the drive circuit 30 instead of the tracking error loop. The track jump pulse is a positive / negative pulse current having the same amplitude as shown in FIG. When the drive circuit 30 receives the track jump pulse, the drive circuit 30 moves the optical pickup 21 in the direction of returning by one track. Further, the 1-track jump generation circuit 34 receives a lock signal from the motor servo circuit 31 indicating that the disk rotation speed after zone switching has reached (locked) a predetermined rotation speed specific to the zone. When the 1-track jump generation circuit 34 receives this lock signal, the 1-track jump generation circuit 34 eliminates the generation of the track jump pulse. That is, the 1-track jump generation circuit 34 starts generation of the track jump pulse after inputting the zone switching detection signal, and thereafter, the motor servo circuit 31.
A track jump pulse is generated at every disk rotation cycle until the lock signal from is input. The 1-track jump generation circuit 34 obtains the disk rotation cycle signal from the frequency-divided signal of the frequency-dividing circuit 32 and the like, and generates the track jump pulse at the same cycle.

Next, the operation of the optical disk reproducing apparatus of the present embodiment, especially at the time of zone switching, will be described.

When a zone change is detected by the zone detection circuit 27 based on the reproduction data obtained from the latch circuit 26 during the disc reproduction, the zone detection circuit 27 outputs the detection signal to the 1-track jump generation circuit 34. Is output.

When the 1-track-jump generation circuit 34 receives this zone switching detection signal, it applies the track-jump pulse as shown in FIG. 21 is moved in the direction of returning one track (track jump). That is, the one-track jump causes the optical pickup 21 to be moved onto the final track of the zone before switching.

Here, as shown in FIG. 11, until the disk rotational speed after the zone switching reaches a predetermined rotational speed specific to the zone (locks), a waiting time after the zone switching occurs for a while. Requires. This waiting time is longer than the time required for the disk to make one revolution.
Therefore, during this waiting time, the 1-track jump generation circuit 34 generates a track-jump pulse at a cycle substantially the same as the disk rotation cycle, so that the optical pickup 21 repeats a 1-track jump at substantially the same position in the zone switching area. To

After that, when the disk rotation speed reaches a predetermined rotation speed peculiar to the zone after switching and locks, the motor servo circuit 31 outputs a lock signal to the one-track jump generation circuit 34. 1-track jump generation circuit 3
When the lock signal is input, the reference numeral 4 stops the generation of the track jump pulse and ends the track jump of the optical pickup 21. As a result, the normal disk reproduction state is restored.

Here, when the first data after zone switching after the last one-track jump is finished and the first data is reproduced, the disk rotation speed has already reached the predetermined rotation speed specific to the zone. Therefore, it is possible to correctly read the data from the first sector after the zone switching.

Although the track jump pulse is applied to the drive circuit in addition to the tracking error loop in this embodiment, the track jump pulse may be applied to the drive circuit instead of the tracking error loop. .

By the way, in this embodiment, the repeating period of the one-track jump immediately after the zone switching is
Since the disc rotation speed changes, the optical pickup 2
Since 1 repeatedly scans a track extending over two zones having different recording linear densities, the PLL circuit 25 is in the phase pull-in state. Therefore, there is a delay time depending on the time response characteristic of the PLL circuit 25 until the phase pull-in of the PLL circuit 25 is completed after the disk rotation number reaches the predetermined rotation number. By properly selecting the time response characteristic of the PLL circuit 25, this delay time can be shortened to such an extent that reproduction of the zone after switching is not affected.

The optical disk reproducing apparatus according to another embodiment shown in FIG. 3 further improves this point. In the figure, the parts having the same names as those in FIG. 1 are designated by the corresponding reference numerals, and the duplicate description of the same parts will be omitted here.

In this embodiment, one difference from the embodiment of FIG. 1 lies in the function of the zone detection circuit 47. The zone detection circuit 47 has a function of detecting the time point of zone switching during disk reproduction, and a function of detecting the time immediately before zone switching and outputting the detection signal to the PLL circuit 45. The PLL circuit 45 operates to fix the frequency of the generated clock signal when the detection signal is input.

The motor servo circuit 51 has a function of sending a lock signal to the one-track jump generation circuit 54 when the disk rotation speed after zone switching reaches (locks) a predetermined rotation speed unique to the zone. In addition, it has a function of outputting this lock signal to the PLL circuit 45. P
When the lock signal is input, the LL circuit 45 releases the fixed state of the frequency of the generated clock signal.

That is, the frequency of the PLL circuit 45 is fixed by the detection signal from the zone detection circuit 47 immediately before entering the phase pull-in process, and the frequency fixing is released at the timing when the disk rotation speed reaches the predetermined rotation speed after the zone switching. To be done.

After the frequency of the clock signal generated by the PLL circuit 45 is fixed, the 1-track jump generation circuit 54 inputs the zone switching detection signal from the zone detection circuit 47 and starts generation of the track jump pulse. Then, based on the lock signal from the motor servo circuit 51, the generation of the track jump pulse is stopped at the same timing as when the frequency fixing of the PLL circuit 45 is released.

Therefore, according to the present embodiment, the phase pull-in time after the disk rotation speed reaches the predetermined rotation speed can be obtained without depending on the time response characteristic of the PLL circuit 45.
It can be sufficiently shrunk so as not to affect the reproduction of the zone after switching, and the data can be correctly reproduced from the tip of the zone after switching.

Next, details of the configuration of the PLL circuit will be described. FIG. 4 is a diagram showing the configuration of this PLL circuit, which is particularly preferably used in the optical disc reproducing apparatus shown in FIG. As shown in the figure, the PLL circuit 25 includes a phase comparator 61, a loop filter 62, and a voltage controlled oscillator 6.
It consists of three. In this PLL circuit 25, the phase comparator 61
At, the phase of the input signal and the output signal of the voltage controlled oscillator 63 are compared to generate a phase error signal. This phase error signal becomes a DC level through the loop filter 62 and is output to the voltage controlled oscillator 63. The voltage controlled oscillator 63 oscillates at a frequency according to the input voltage, and the oscillation output is PL
It becomes the output of the L circuit 25.

FIG. 5 is a diagram showing the configuration of another PLL circuit, which is particularly used in the optical disk reproducing apparatus shown in FIG. The PLL circuit 45 shown in the figure comprises a phase comparator 71, a loop filter 72, a hold circuit 73, and a voltage controlled oscillator 74. Here, the hold circuit 73 is
The voltage of the loop filter 72 at the time when the detection signal immediately before the zone switching is input from the zone detection circuit 47 shown in FIG. 3 is held, and then the holding voltage is applied to the voltage controlled oscillator 74 until the lock signal is input from the motor servo circuit 51. Continue to add. In other periods, the voltage of the loop filter 72 is applied to the voltage controlled oscillator 74 as it is. Therefore, during the voltage holding period, the output frequency of the PLL circuit 47 becomes almost constant at the value of the predetermined reproduction data rate. Other operations are the same as those of the PLL circuit shown in FIG.

Further, FIG. 6 is a diagram showing a configuration of a PLL circuit having a function equivalent to that of the PLL circuit of FIG. The PLL circuit shown in the figure includes a reference signal oscillator 81, a switch 82,
It comprises a phase comparator 83, a loop filter 84, and a voltage controlled oscillator 85. Here, the reference signal oscillator 81 oscillates a reference signal having a frequency equal to the center value of the reproduction data rate that should be originally obtained over each zone reproduction. The switch 82 is for switching the input to the phase comparator 83 between the reference signal and the reproduction data. The switching is performed by the detection signal immediately before the zone switching from the zone detection circuit 47 and the lock from the motor servo circuit 51. It is performed based on the signal. That is, switch 82
Inputs the reproduction data to the phase comparator 83 until the detection signal immediately before the zone switching is input, and when the detection signal immediately before the zone switching is input, inputs the reference signal to the phase comparator 83 until the lock signal is input thereafter. Switch to. Other operations are the same as those of the PLL circuit shown in FIG.

In the above embodiment, the motor servo circuit controls the rotation of the disk motor on the basis of the signal obtained by dividing the synchronizing signal component contained in the signal read from the disk. The configuration is not limited to being applied to the optical disk reproducing device.

For example, as shown in FIG. 7, an FG (frequency generation) amplifier 101 (which may be a Hall element) is connected to the disk motor 93, and the frequency signal of this FG amplifier 101 and the clock signal of the reference clock generation circuit 102 are connected to each other. The present invention can be similarly applied to an optical disk reproducing apparatus in which the comparison error signal is supplied to the motor servo circuit 95 to control the rotation of the disk motor 93. In this optical disc reproducing apparatus, the frequency generated by the reference clock generation circuit 102 is switched based on the zone identification signal from the zone detection circuit 97.

Further, in the above embodiments, the zone detection circuit detects the zone switching from the reproduction data, but the zone switching may be detected from the oscillation frequency of the PLL circuit.

[0042]

As described above in detail, according to the optical disk reproducing apparatus and the control method thereof of the present invention, from the time when the zone switching is detected until the disk rotational speed reaches the predetermined rotational speed after the zone switching, The optical pickup repeats one track jump at the same position in the same zone switching area, and ends the track jump when the disk rotation speed reaches a predetermined rotation speed after zone switching. Therefore, the time required for reading again immediately after zone switching. Can be minimized throughout. Also, it is possible to correctly reproduce from the first data after the zone switching.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an optical disk reproducing device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a waveform of a track jump pulse.

FIG. 3 is a block diagram showing a configuration of an optical disk reproducing device according to another embodiment of the present invention.

FIG. 4 is a PL suitable for the optical disk reproducing device shown in FIG.
It is a block diagram showing a configuration of an L circuit.

FIG. 5 is a PL suitable for the optical disk reproducing device shown in FIG.
It is a block diagram showing a configuration of an L circuit.

6 is a block diagram showing a configuration of another PLL circuit having a function equivalent to that of the PLL circuit shown in FIG.

FIG. 7 is a block diagram showing the configuration of another optical disc reproducing apparatus to which the present invention can be applied.

FIG. 8 is a diagram showing an MCLV type disc.

9 is a diagram showing a disc rotation speed of the MCLV disc shown in FIG. 8. FIG.

10 is a diagram showing the relationship between the sector lengths of the zones on the MCLV disc shown in FIG. 8;

11 is a diagram showing an actual disc rotation speed of the MCLV disc shown in FIG. 8. FIG.

12 is a diagram showing a reproduction data rate of the MCLV disc shown in FIG.

FIG. 13 is a block diagram showing a configuration of a conventional optical disc reproducing apparatus.

[Description of Codes] D ... Optical disc, 21 ... Optical pickup, 22 ... RF amplifier, 23 ... Waveform equalizer, 24 ... Data slicer, 25
... PLL circuit, 26 ... Latch circuit, 27 ... Zone detection circuit, 28 ... Tracking error detection circuit, 29 ... Loop filter, 30 ... Drive circuit, 31 ... Motor servo circuit,
32 ... Frequency divider circuit, 33 ... Disk motor, 34 ... 1 track jump generation circuit.

Claims (8)

[Claims] 1. An optical disc in which the entire recording area is divided into zones each consisting of a plurality of adjacent tracks, and the recording linear density continuously changes within each zone, at a constant reproduction data rate over each zone. In an optical disk reproducing apparatus for reproducing, an optical pickup for reading a recording signal of the optical disk, a detecting means for detecting a change of zone in which a signal is read by the optical pickup, and a detecting means for detecting a change of zone, Control means for causing the optical pickup to make a track jump in the direction of returning by one track at almost every rotation cycle of the optical disk, and for terminating the track jump when the disk rotation speed reaches a predetermined rotation speed after the zone switching. An optical disc reproducing apparatus comprising: 2. An optical disc in which the entire recording area is divided into zones each consisting of a plurality of adjacent tracks and a signal is recorded at a different linear recording density for each zone is reproduced at a constant reproduction data rate over each zone. In the optical disc reproducing apparatus, an optical pickup for reading a recording signal of the optical disc, a pickup feeding mechanism for moving the optical pickup in a radial direction of the optical disc, and a detection unit for detecting a changeover of a zone in which a signal is read by the optical pickup. When a zone change is detected by the detection means, a pulse signal for causing the optical pickup to make a track jump in the direction of returning one track is generated almost every rotation cycle of the optical disc and supplied to the pickup feed mechanism. Track jump pulse generating means, The disk rotation speed during the track jump period is monitored, and when the disk rotation speed reaches a predetermined rotation speed after the zone switching, a request signal to the track jump pulse generating means to end the generation of the pulse signal. And a control means for outputting the optical disc reproducing apparatus. 3. The optical disk reproducing apparatus according to claim 1, wherein the optical pickup reads a signal from the read signal of the optical pickup, the clock generating means generates a clock signal for reproduction in phase synchronization with the read signal. Second detecting means for detecting immediately before the zone switching, and when the second detecting means detects the zone just before the zone switching, the frequency of the clock signal of the clock generating means is set to the constant reproduction data rate. And a releasing means for releasing the fixed clock frequency by the clock frequency fixing means when the disk rotational speed reaches a predetermined rotational speed after the zone switching. An optical disk reproducing apparatus characterized by: 4. The optical disk reproducing apparatus according to claim 3, wherein the clock generating means compares the read signal of the optical pickup with the output signal of the voltage controlled oscillator and outputs a phase error signal. And a voltage-controlled oscillator that outputs a frequency signal corresponding to the phase error signal from the phase comparator as the reproduction clock signal, and the clock frequency fixing means is the second detection means. The phase error signal output from the phase comparator when the time immediately before the zone switching is detected is held until the disk rotational speed reaches a predetermined rotational speed after the zone switching and is supplied to the voltage controlled oscillator during this period. An optical disk reproducing apparatus having a hold circuit for continuing. 5. The optical disk reproducing apparatus according to claim 3, wherein the clock generating means compares the phases of the read signal of the optical pickup and the output signal of the voltage controlled oscillator and outputs a phase error signal. And a voltage-controlled oscillator that outputs a frequency signal corresponding to the phase error signal from the phase comparator as the clock signal for reproduction, and the clock frequency fixing means is substantially equal to the constant reproduction data rate. A reference signal generating circuit for generating a reference signal having the same frequency and an input to the phase comparator are switched between a read signal of the optical pickup and a reference signal of the reference signal generating circuit, Since the second detection means detects the time immediately before the zone switching, the disk rotation speed reaches the predetermined rotation speed after the zone switching. The optical disk reproducing apparatus until that, characterized in that a switch for switching operation to enter the reference signal to the phase comparator. 6. An optical disc in which the entire recording area is divided into zones each consisting of a plurality of adjacent tracks and a signal is recorded at a different linear recording density for each zone is reproduced at a constant reproduction data rate over each zone. In the optical disc reproducing apparatus, a step of detecting a change of a zone where a signal is read by an optical pickup, and when the change of the zone is detected, the optical pickup is moved back one track at a time about every rotation cycle of the optical disc. A method of controlling an optical disk reproducing device, comprising: a step of jumping; and a step of ending the track jump when the disk rotational speed reaches a predetermined rotational speed after zone switching. 7. An optical disk in which the entire recording area is divided into zones each consisting of a plurality of adjacent tracks and a signal is recorded at a different linear recording density for each zone is reproduced at a constant reproduction data rate over each zone. In the optical disc reproducing apparatus including an optical pickup for reading a recording signal of the optical disc and a pickup feed mechanism for moving the optical pickup in a radial direction of the optical disc, the signal is read by the optical pickup. And a pulse signal for causing the optical pickup to perform a track jump in the direction of returning one track when the zone change is detected, the pickup feed mechanism And the track jar Monitoring the number of revolutions of the disc during the pumping period, and when the number of revolutions of the disc reaches a predetermined number of revolutions after the zone switching, the supply of the pulse signal to the pickup feed mechanism is terminated. Method for controlling optical disk reproducing apparatus. 8. The control method of the optical disc reproducing apparatus according to claim 6, wherein the optical disc reproducing apparatus further comprises clock generating means for generating a reproduction clock signal phase-synchronized with the read signal of the optical pickup. A step of detecting immediately before switching of a zone in which a signal is read by the optical pickup; and a step of detecting a frequency of a clock signal of the clock generating means when the switching is detected just before switching of the zone. The optical disk reproducing apparatus further comprises a step of fixing the value to the same value as the data rate, and a step of releasing the fixing of the clock frequency when the disk rotational speed reaches a predetermined rotational speed after the zone switching. Control method.