JPH07129983A - Optical disk device - Google Patents

Abstract

PURPOSE:To read address information, etc., simultaneously with the restart of servo and to improve an earthquake-proof property of a device by stopping a servo mechanism when the abnormality of servo operation is judged and returning an optical pickup to a recording area. CONSTITUTION:In the case of judging that information from a mini disk MD 1 can not be read out, and the servo operation is abnormal and focus servo operation is normal, a tracking servo and a slide servo are interrupted temporarily. Then, the optical pickup 3 is moved in the inner peripheral direction of the MD 1 by an amount sufficient for moving from an outer peripheral side unrecorded area to the information area, thereafter respective servos are started again. Thus, even when the servos become abnormal due to the shock, etc., from the outside, and the optical pickup is skipped to the outer peripheral side unrecorded area, the address information is read at the time of the restart, and the read process is performed continuously without stopping reproducing operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device capable of recording and reproducing a plurality of information on a disk-shaped recording medium such as a mini disk.

[0002]

2. Description of the Related Art As a mini disk device (optical disk device) for recording / reproducing information on / from a mini disk (hereinafter referred to as MD) which is a disk-shaped recording medium, a laser beam emitted from an optical pickup to an MD is used. Is divided into a main beam for reading the information signal and a pair of sub-beams for detecting the tracking servo signal,
A so-called three-beam type is known, and in this, the following four types of servo mechanisms are required as a servo mechanism for capturing a specific track on the MD and reading an information signal.

A focus servo that optically detects a focus error and keeps the distance between the objective lens inside the optical pickup and the MD constant in order to couple the signal reading optical system of the optical pickup and the MD under the optimum conditions.

A tracking servo that optically detects a tracking error and positions the objective lens inside the optical pickup at the center of the track in order to stably trace a predetermined track.

A spindle servo that controls the rotation speed of the MD by detecting the signal period in order to reproduce the signal waveform recorded on the track as information.

A slide servo that moves and positions the optical pickup over the entire MD based on a tracking servo signal to cover the entire area of the MD.

As a conventional mini disk device provided with each servo mechanism as described above, one having a structure shown in the block diagram of FIG. 5 is known. In this case, with respect to MD1 which is rotationally driven by the spindle motor 2,
The optical pickup 3 is adapted to read and write various kinds of information, and as an element for a servo mechanism, the optical pickup 3 irradiates the MD1 with laser light under optimum conditions to detect signals. The objective lens 3a described above, a focus actuator 3b that adjusts and drives the distance between the objective lens 3a and MD1, and a tracking actuator 3c that drives the objective lens 3a to follow the MD1 in the track direction are built-in. The optical pickup 3 is driven by a guide rail 4 and a slide motor 5 to a designated track position of MD1, and the fact that the pickup 3 has been moved to the innermost peripheral area of MD1 means that the lead-in is performed. It is detected by the switch 6.

The various signals detected by the optical pickup 3 are level-amplified by an amplifier 10 and then separated and output into an information signal and a servo error signal. Among them, the information signal passes through a changeover switch 7. Are input to the signal processing circuit 11. In the MD1, the information recording method is the method of recording by the intensity of reflected light (pit) as in the compact disc (hereinafter referred to as CD) and the method of recording by the difference in the deflection angle of the reflected light as in the magneto-optical disc. How to do (groove)
Since there are two ways of reading, and the principle of reading signals is different, the signal processing circuit 11 is provided with reading means of two systems corresponding to each of them, and the changeover switch 7 is used to switch each means. Is provided. The music information signal restored by the signal processing circuit 11 is output from the output terminal 12 to the outside of the device.

On the other hand, the servo error signal output from the amplifier 10 is input to each of the focus servo circuit 14, the tracking servo circuit 15, and the spindle servo circuit 16, and the output signal of the tracking servo circuit 15 is the slide servo circuit 13. It is designed to be input to. A control signal from the system controller 20 is also input to each servo circuit 13 to 16, and each servo control signal is generated by this control signal and each servo error signal. A servo control signal is output from 16 to various motors and actuators to perform servo drive on MD1.

The system controller 20 controls the changeover switch 7 in addition to giving an operation instruction to each of the servo circuits 13 to 16 according to the operation mode of the mini disk device. further,
The position control of the optical pickup 3 is performed based on the address information from the signal processing circuit 11, and the information read control from various MDs 1 is also performed.

In such a mini disk device, M
In order to correctly read the information from D1, it is necessary that various servos for MD1 are working normally, and if any one of the servo operations is abnormal, it is impossible to read the information. Become. Furthermore, since each servo does not operate independently and is related to each other, if any one servo operation becomes abnormal, it may affect other servo operations as shown below. Becomes In other words, when the focus servo becomes abnormal, the servo error signal cannot be obtained at all.
Affects each servo operation of the spindle servo and slide servo.

When the tracking servo becomes abnormal → The signal waveform from the MD1 cannot be obtained, which affects the spindle servo and
It also affects the above-mentioned slide servo that operates using this servo output as an input.

When the above-mentioned spindle servo becomes abnormal → Other servos are not affected.

When the above-mentioned slide servo becomes abnormal → The optical pickup 3 is no longer localized at the designated track position, which affects the above-mentioned tracking servo.

That is, in order to correctly read information from the MD1, it is necessary that all of these servo operations are normal. If any one of the servo operations becomes abnormal, it is not necessary to repair only that servo. It is necessary to take measures considering the influence on other servo operations. Therefore, conventionally, the system controller 20 is programmed with a method for coping with an abnormal servo operation in consideration of such influence on other servo operations.

Next, a method of coping with a servo operation abnormality in the conventional mini disk device will be described with reference to the flowchart of FIG. 6 showing a processing procedure for reading music information.

First, the address information for confirming the current position of the optical pickup 3 is read (step 41, hereinafter step is abbreviated as S), and whether or not there is an error in the read data is recorded with the address value and the parity. Check using the value (S42). As a result, if there is no error, it is determined whether or not the designated track is the recorded address (S43), and if the position is correct, the music information is read (S44). If the position is incorrect, the music information is read. After the track search processing is performed to adjust the position of the optical pickup 3 (S45), it is determined whether the target position is a pit recording area or a groove recording area (S46), and signal processing is performed depending on each case. After switching the signal processing method in the circuit 11 (S47, 48), the process returns to S41 and the information reading process is repeated.

On the other hand, if there is an error in the address information in S42, the current position of the optical pickup 3 is unknown, so processing is performed so that the address information can be read normally thereafter. First, it is determined whether or not the focus servo operation is normal (S50), and if normal, it is determined whether or not a certain time has elapsed since the music information reading process of the address was started (S51). If the predetermined time has not elapsed, the process returns to S41 and the information reading process is repeated (this is a countermeasure against a temporary error due to damage of MD1 or the like), while if it has elapsed, the tracking servo is abnormal. Then, the tracking servo and the slide servo are once stopped to stop the abnormal operation (S52), the tracking servo and the slide servo are restarted (S53), and the process returns to S41 to repeat the information reading process. .

On the other hand, if the focus servo operation is abnormal in S50, all the servo operations are temporarily stopped (S60), and then the focus servo and the spindle servo are restarted in order (S61 and 62), and then, After restarting each servo of the tracking servo and the slide servo (S63), the process returns to S41 and the information reading process is repeated.

By the above processing, even if the servo operation becomes abnormal due to an external shock or the like and various information from the MD1 cannot be read correctly, the state is restored and the information is read again correctly. ing.

[0021]

However, in the measures by the above-mentioned conventional device, the position of the optical pickup 3 is not taken into consideration, and therefore, in the case where the servo operation becomes abnormal, the state cannot be restored. Will occur. This is mainly due to the state of the recording area of MD1 and the recording method thereof.

That is, there are two types of MD1 handled in the above-mentioned mini disk device, a read-only type and a recording / playback type. Among them, the read-only MD1a is shown in FIG. 3 which is an explanatory view of the present invention. As shown in the drawing, a lead-in area and a music information area are formed in order from the outermost side, and a non-recorded area exists on the outermost side. on the other hand,
In the recording / reproducing MD 1b, as shown in FIG. 4 (an explanatory view of the present invention), the lead-in area,
A user TOC (Table Of Contents) area and a music information area are formed, and also in this area, there is a non-recorded area on the outermost side.

Therefore, (1) When the optical pickup 3 is moved to the non-recorded area on the outer peripheral side of the disk due to an abnormality in the tracking servo and the slide servo during the reproduction of information from the MD 1, the conventional apparatus is used. As a countermeasure, although the servo operation itself can be restored, even if the servo operation is restored, the information such as the address cannot be read thereafter. Although the non-recorded area in MD1 exists on the innermost side of the disc, the optical pickup 3 is not moved to this point by the lead-in switch 6, so it is necessary to consider the non-recorded area on the inner side of the disc. Absent.

(2) During reproduction of information from the MD 1, the focus servo becomes abnormal, and other servo operations also become abnormal due to the influence, and the optical pickup 3 passes through the non-recorded area on the outer peripheral side of the disk, and then outside the disk. If it has been moved to, MD will be placed in the laser irradiation area of the optical pickup.
Since there is no 1 there, focus servo starts,
The other servos cannot be restarted.

In the read-only MD1a, both the lead-in area and the music information area are pit recording areas similar to those in the CD. In the recording / reproducing MD1b, the lead-in area is a pit recording area, but the user TOC and The music information area is a groove recording area similar to that of the magneto-optical disk. Therefore, (3) of the MD1, a servo operation abnormality occurs during the reproduction of information to the recording / reproducing MD 1b and the reading of the lead-in area, and the optical pickup 3
Is moved to the music information area (or user TOC area), or conversely, the optical pickup 3 is moved to the lead-in area while reading the music information area (or user TOC area). Even if the servo operation is restored, the signal processing circuit 11 is not switched, so that the information cannot be read.

In the conventional case, the above (1)-
If the state of (3) cannot be restored, the state in which various information cannot be read from the MD1 cannot be recovered, and even if the device is in the reproducing state, there is no choice but to stop the operation once. As a result, there is a problem that the earthquake resistance of the device is insufficient.

[0027]

In order to solve the above-mentioned problems, an optical disk device according to a first aspect of the present invention captures a specific track on a disk-shaped recording medium with an optical pickup and outputs an information signal on the track. In order to read the information, it was judged that there was an abnormal servo operation because the information signal from the disk-shaped recording medium could not be read normally in the optical disk device in which various servo operations such as focus servo, tracking servo, spindle servo and slide servo were performed. In this case, the tracking servo and the slide servo are temporarily stopped, the optical pickup is moved in the inner peripheral direction of the disk-shaped recording medium by a predetermined amount, and then the first servo operation restoration means for activating each stopped servo is provided. It is characterized by being.

In order to solve the above-mentioned problems, an optical disk apparatus according to a second aspect of the present invention uses a focus servo in order to capture a specific track on a disk-shaped recording medium by an optical pickup and read an information signal on the track. In an optical disk device in which various servo operations such as tracking servo, spindle servo, and slide servo are performed, it is determined that the information signal from the disk-shaped recording medium cannot be read normally and the servo operation is abnormal, and If it is determined that the focus servo operation is abnormal,
A second servo operation restoration means is provided for temporarily stopping all the servo operations, moving the optical pickup by a predetermined amount in the inner peripheral direction of the disk-shaped recording medium, and then reactivating all servos. I am trying.

In order to solve the above-mentioned problems, an optical disk device according to claim 3 of the present invention is the optical disk device according to claim 1 or 2, wherein the first or second servo operation restoration means is the disk. If the recording medium is a recordable / reproducible type, the optical pickup is moved to the innermost position of the disc after each predetermined servo operation is stopped, and the information signal read by the optical pickup is changed according to the recording method. The feature is that the servo is restarted after switching the signal processing circuit to be restored according to the recording method of the innermost circumference position of the disc so that the servo can be restored.

[0030]

According to the structure of claim 1 of the present invention, when the first servo operation restoration means determines that the information from the disk-shaped recording medium cannot be normally read and the servo operation is abnormal, the tracking servo and the slide operation are performed. Stop the servo and
After that, the optical pickup is moved by a predetermined amount in the inner peripheral direction of the disk-shaped recording medium, and then each of these servos is activated again. Even if the slide servo becomes abnormal, the servo operation can be restored. The optical pickup is moved in the inner circumferential direction of the disk-shaped recording medium by a predetermined amount before the servo operation is stopped and then restarted. Even if the optical pickup is moved to the non-recorded area on the outer peripheral side of the disk-shaped recording medium, the optical pickup is pulled back from the non-recorded area when restarted, and the address information and the like can be read again when the servo is restarted. It will be possible.

According to the second aspect of the present invention, the second servo operation restoration means determines that the information from the disk-shaped recording medium cannot be read normally and the servo operation is abnormal, and the abnormality is detected. When it is determined that the focus servo operation is abnormal, all the servo operations are temporarily stopped, and then the optical pickup is moved in the inner circumferential direction of the disc-shaped recording medium by a predetermined amount, and then all servos are activated again. As a result, even if the focus servo becomes abnormal due to an external shock or the like, and other servo operations become abnormal due to this, all the servo operations can be restored. The optical pickup is moved by a predetermined amount in the inner peripheral direction of the disk-shaped recording medium before the entire servo operation is stopped and then restarted. Even if the optical pickup is moved to the outside of the disc-shaped recording medium, the optical pickup is pulled back onto the disc-shaped recording medium when it is restarted, and each servo can be restarted and the address information, etc. can be restarted. Can be read.

According to the third aspect of the present invention, the first or second servo operation restoring means temporarily stops each predetermined servo operation when the disk-shaped recording medium is a recordable / reproducible type. After that, the optical pickup is moved to the innermost circumferential position of the disc, and the signal processing circuit that restores the information signal read by the optical pickup according to the recording method is changed according to the recording method of the innermost circumferential position of the disc. Since each servo is restarted after switching so as to enable restoration, for example, while the lead-in area is being read, a servo operation abnormality occurs and the optical pickup is in the music information area (or user TOC area). ), Or vice versa, while the optical information is being read from the music information area (or user TOC area), the optical pickup moves to the lead-in area. Even if had been moving, certainly, it is possible to read the information. In the conventional device, since the signal processing circuit 11 is not switched even if the servo operation is restored, the information cannot be read when the optical pickup is moved to an area having a different recording method. It had been.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe one embodiment of the present invention with reference to FIGS.

As shown in the block diagram of FIG. 2, the mini disk device as the optical disk device according to the present embodiment reads and writes various information from MD1 on which various information is recorded and the recording surface of this MD1. Optical pickup 3
Is equipped with. The optical pickup 3 is of a so-called three-beam type in which the laser light radiated to the MD 1 is divided into a main beam for reading an information signal and a pair of sub-beams for detecting a tracking servo signal. The optical pickup 3 includes, as an element for a servo mechanism, an objective lens 3a for irradiating the MD1 with laser light under optimum conditions to detect a signal, and a distance between the objective lens 3a and MD1. The focus actuator 3b for adjustment driving and the objective lens 3a are mounted on the MD1.
And a tracking actuator 3c for driving to follow in the track direction.

Further, in the above-mentioned mini disk device, the spindle motor 2, the guide rail 4, the slide motor 5, the lead-in switch 6, the amplifier 10, the changeover switch 7, the signal processing circuit 11, the output terminal 12, the slide servo circuit 13, the focus. A servo circuit 14, a tracking servo circuit 15, a spindle servo circuit 16, and a system controller 17 are provided.

The spindle motor 2 drives the MD 1 to rotate, and the guide rail 4 and the slide motor 5 are
A slide mechanism for driving the optical pickup 3 to a designated track position of the MD 1 is configured. Further, the lead-in switch 6 detects that the optical pickup 3 has been moved to that position in order to quickly read the TOC information recorded in the innermost disc area of the MD 1, and the amplifier 10 is The level of various signals detected by the pickup 3 is amplified.

The various signals amplified by the amplifier 10 are separated into an information signal and a servo error signal, of which the information signal passes through the changeover switch 7 and is input to the signal processing circuit 11 for restoring the information signal. It In MD1,
There are two types of information recording methods: a method of recording by the intensity of reflected light (pit) as in CD, and a method of recording by the difference in deflection angle of reflected light (groove) as in magneto-optical disk. Each has a different signal reading principle. Therefore, the signal processing circuit 11 is provided with two systems of reading means corresponding to each of them, and the changeover switch 7 is provided to switch the respective means. The music information signal restored by the signal processing circuit 11 is output to the output terminal 1
2 is output to the outside of the device.

On the other hand, the servo error signals are also output from the amplifier 10, and these servo error signals are input to the focus servo circuit 14, the tracking servo circuit 15, and the spindle servo circuit 16, and the output signals of the tracking servo circuit 15 are also provided. Is input to the slide servo circuit 13. A control signal from the system controller 17 is also input to each servo circuit 13-16, and each servo control signal is generated by this control signal and each servo error signal. A servo control signal is output from 16 to various motors and actuators to perform servo drive on MD1.

The system controller 17 controls the changeover switch 7 in addition to giving an operation instruction to each of the servo circuits 13 to 16 according to the operation mode of the mini disk device. further,
The position control of the optical pickup 3 is performed based on the address information from the signal processing circuit 11, and the information read control from various MDs 1 is also performed. The system controller 17 will be described in detail later.
However, as the first and second servo operation restoration means of the present invention, the drive of each servo circuit 13 to 16 is controlled, and the processing procedure is programmed in a storage unit (not shown).

Now, each servo mechanism implemented by the slide servo circuit 13, the focus servo circuit 14, the tracking servo circuit 15, and the spindle servo circuit 16 which are formed by the operation instruction of the system controller 17 will be described.

The focus servo implemented by the focus servo circuit 14 optically detects a focus error so that the signal reading optical system of the optical pickup 3 and the MD 1 are coupled under the optimum condition, and the inside of the optical pickup 3 is detected. This is a servo for keeping the distance between the objective lens 3a and MD1 constant.

The tracking servo implemented by the tracking servo circuit 15 optically detects a tracking error so as to stably trace a predetermined track (not shown) on the MD 1, and the tracking servo inside the optical pickup 3 is carried out. Servo for positioning the objective lens 3a at the center of the track.

The spindle servo implemented by the spindle servo circuit 16 detects the signal period of the signal recorded on the track so as to reproduce the signal waveform as information, and MD
1 is a servo for controlling the rotation speed of the spindle motor 2, that is, the rotation speed of the spindle motor 2.

The slide servo implemented by the slide servo circuit 13 moves and positions the optical pickup 3 over the entire MD1 based on the tracking servo signal output from the tracking servo circuit 15 in order to cover the entire MD1. Is a servo for.

There are two types of MD1 handled by such a mini disk device, a playback-only MD and a recording / playback MD, and of these, the playback-only MD1a, as shown in FIG. There is a lead-in area in which various parameters and TOC information relating to the MD 1a are recorded, a music information area is located outside the lead-in area, and a non-recorded area is located at the outermost side. Both the lead-in area and the music information area,
It is a pit recording area similar to a CD. On the other hand, in the recording / playback MD 1b, as shown in FIG.
A lead-in area in which various parameters relating to D1b are recorded, a user TOC area outside the area, a music information area outside the area, and a non-record area on the outermost area. The lead-in area is a pit recording area, but both the user TOC area and the music information area are groove recording areas similar to those of a magneto-optical disk.

Next, the operation of the above-mentioned mini disk device will be described with reference to M
The case of reproducing the recording / reproducing MD 1b of D1 will be described as an example.

In the above device, when the reproduction mode of MD1b is instructed, the system controller 17 first
The slide servo circuit 13 is instructed to move the optical pickup 3 in the inner circumferential direction of the disc. In this command state, the lead-in switch 6 causes the optical pickup 3 to move to M
The process is continued until it is recognized that the D1b has been moved to the innermost position. Next, the system controller 17 sequentially issues a servo operation start command to the focus servo circuit 14, the spindle servo circuit 16, the tracking servo circuit 15, and the slide servo circuit 13 to start the servo operation for the MD 1b.

When the servo operation is normally started, the system controller 17 sets the changeover switch 7 on the pit side (because the innermost peripheral portion of the MD 1b is the pit recording area regardless of whether the recording / reproducing MD or the reproducing-only MD). The current position of the optical pickup 3 is confirmed by the address information read via the signal processing circuit 11, and then the information in the lead-in area of the MD 1b is read. Information indicating the information of the MD 1b is recorded in the lead-in area.
If the disc 1b is recognized as a recording / reproducing disc, a command is issued to the tracking servo circuit 15 and the slide servo circuit 13 to move the optical pickup 3 to the outer peripheral side of the disc, and the selector switch 7 is switched to the groove side. Access the TOC area and read the information. Since information such as the address position of each information track recorded on the MD 1b is recorded in the user TOC area, the system controller 17 records a track specifying the optical pickup 3 based on this information. A command is issued to the tracking servo circuit 15 and the slide servo circuit 13 in order to move to the address information track position, and the reproduction operation of the track is performed when the movement of the optical pickup 3 is completed.

As described above, in such a mini disk device, in order to correctly read information from the MD1, it is necessary that various servos for the MD1 are operating normally, and even if any one of the servos operates, the servo operation is not possible. If it becomes abnormal, it will be impossible to read the information, so
Conventionally, not only the restoration of the servo concerned, but also the countermeasure considering the influence on other servo operation has been taken. However, in the countermeasure by the conventional device, since the position of the optical pickup 3 is not taken into consideration, the tracking servo and the slide servo become abnormal, and the optical pickup 3 is moved to the non-recorded area on the outer peripheral side of the disc in MD1. If the optical pickup 3 is moved, or the focus servo becomes abnormal and other servo operations also become abnormal due to the influence, the optical pickup 3 is moved outside the MD1,
Alternatively, in the recording / reproducing MD 1b of the MD 1, while the lead-in area is being read, a servo operation abnormality occurs and the optical pickup 3 causes the optical information area (or the user TOC).
Area), or conversely, when the optical pickup 3 is moved to the lead-in area while reading the information in the music information area (or user TOC area), the information cannot be read. I couldn't.

Therefore, as described above, the system controller 17 of the mini disk device of this embodiment is programmed so as to take the position of the optical pickup 3 into consideration. The coping method will be described based on the flowchart of FIG. 1 showing the processing procedure when reading the music information.

First, the address information for confirming the current position of the optical pickup 3 is read (S1), and it is checked whether or not there is an error in the read data by using the parity value recorded together with the address value (S2). . As a result, if there is no error, it is determined whether or not the designated track is the recorded address (S3), the music information is read at the correct position (S4), and the music information is read at the wrong position. After performing track search processing to adjust the position of the optical pickup 3 (S
5) Then, it is determined whether the target position is a pit recording area or a groove recording area (S6), and the changeover switch 7 is changed according to each case to change the signal processing method in the signal processing circuit 11. After (S7
8) Return to S1 and repeat the information reading process.

On the other hand, if there is an error in the address information in S2, since the current position of the optical pickup 3 is unknown, processing is performed thereafter so that the address information can be read normally. In that case, first, it is determined whether the focus servo operation is normal (S10), and if it is normal, it is determined whether a certain time has elapsed since the music information reading process of the address was started (S11). If it has not elapsed, the process returns to S1 and the information reading process is repeated.
This is a countermeasure against a case where an error temporarily occurs due to damage of MD1 or the like. If a certain time has passed in S11, it is determined that the tracking servo is abnormal, the tracking servo and the slide servo are once stopped to stop the abnormal operation (S12), and the type of MD1, that is, the reproduction-only MD1a or the recording / reproduction is performed. It is judged whether it is for MD1b (S1
3).

If it is the reproduction-only MD 1a in S13, the optical pickup 3 is moved toward the inner circumference of the disc for, for example, 200 ms
(S1
6), the tracking servo and the slide servo are restarted (S17), and the process returns to S1 to repeat the information reading process. On the other hand, in the case of the recording / reproducing MD 1b, the optical pickup 3 is moved in the inner circumferential direction of the disc to the innermost circumferential position of the disc (position of the lead-in switch 6) (S1).
4), the changeover switch 7 is changed to change the signal processing circuit 1
1 is switched to the pit side (S15), and then the tracking servo and slide servo are restarted (S1).
7) Then, returning to S1, the information reading process is repeated.

If the focus servo operation is abnormal in S10, all servo operations are temporarily stopped (S20), and then it is determined whether the MD1 type is the reproduction-only MD1a or the recording / reproducing MD1b. (S21),
In the case of the read-only MD 1a, the optical pickup 3 is moved in the inner circumferential direction of the disc for, for example, 400 ms (in this case, since the optical pickup 3 may be moved to the outside of the disc, the optical pickup 3 is moved to the music area from the outside of the disc. (S24), then the focus servo and spindle servo are restarted in order (S25.2).
6) Next, after restarting each servo of the tracking servo and the slide servo (S27), the process returns to S1 and the information reading process is repeated.

On the other hand, in the case of the recording / reproducing MD 1b, the optical pickup 3 is moved in the inner circumferential direction of the disc to the innermost circumferential position of the disc (position of the lead-in switch 6) (S22), and then the changeover switch 7 is changed over. The signal processing circuit 11 is switched to the pit side (S23), and then
All servos are activated in S25 to S27, and the process returns to S1 to repeat the information reading process. By such processing, even when the servo operation becomes abnormal due to an external shock or the like and various information from the MD1 cannot be correctly read, the state is surely restored and the information is read again correctly. .

As described above, in the optical disk device of this embodiment, as the first servo operation restoration means, it is judged that the information from the MD1 cannot be read normally and the servo operation is abnormal (S2), and the focus servo is performed. When it is determined that the operation is normal (S10), the tracking servo and the slide servo are temporarily stopped (S12), and then the optical pickup 3 is moved toward the disc inner peripheral direction of the MD1 by a predetermined amount (no recording on the disc outer peripheral side). After being moved from the area to the music information area for a sufficient period (S16), each of these servos is activated again (S1).
7). Therefore, due to external shock, for example, the tracking servo or slide servo becomes abnormal,
Moreover, even if the optical pickup 3 is largely moved to the non-recorded area on the outer peripheral side of the disk-shaped recording medium when the servo is abnormal, the optical pickup 3 is moved from the non-recorded area when the servo is restarted. Since it is pulled back, the address information and the like can be read again. Thereby, the reading process of the music information and the like can be continuously performed without stopping the reproducing operation, and as a result, the earthquake resistance of the device can be improved.

Further, in the optical disk device of the present embodiment, as the second servo operation restoration means, it is judged that the information from MD1 cannot be read normally and the servo operation is abnormal (S2).
When it is determined that the abnormality is an abnormality in the focus servo operation (S10), all the servo operations are temporarily stopped (S20), and then the optical pickup 3 is moved to the MD.
1 in the inner circumferential direction of the disc (in this case, since the optical pickup 3 may have been moved to the outside of the disc, a period sufficient for moving the disc from the outside to the music area) ( (S24), all servos are activated again (S25-27). Therefore, due to external shock, etc., the focus servo becomes abnormal, and as a result, other servo operations also become abnormal.
Moreover, even if the optical pickup 3 is largely moved and moved past the non-recorded area of the MD1 to the outside of the disc, the optical pickup 3 is moved to the M level when the servos are restarted.
Since it is pulled back onto D1, each servo can be restarted and the address information and the like can be read again. That is, even by this, without stopping the reproduction operation,
It is possible to continue the reading processing of music information and the like, and as a result, the earthquake resistance of the device can be further improved.

Furthermore, in the optical disk device of this embodiment,
The first and second servo operation restoration means are the MD1
Is the recording / reproducing MD 1b, after temporarily stopping each servo operation, the optical pickup 3 is moved to the innermost position of the disc, and the signal read by the optical pickup 3 is restored according to the recording method. The signal processing circuit 11,
Each servo is restarted after the changeover switch 7 is switched so that the restoration according to the recording method of the innermost position of the disc can be performed, that is, the information can be restored from the pits (S13). ~ 15, S21 ~ 2
3). Therefore, for example, while the lead-in area is being read, a servo operation abnormality occurs and the optical pickup 3 is moved to the music information area (or user TOC area), or conversely, the music information area (or user TOC area). While reading music information from the optical pickup 3
Even if is moved to the lead-in area, the information can be surely read. As a result, even by this, it becomes possible to continue the reading processing of the music information and the like without stopping the reproducing operation, and it is possible to further improve the earthquake resistance of the apparatus.

[0059]

According to the optical disk device of claim 1 of the present invention,
As described above, when it is determined that the information signal from the disc-shaped recording medium cannot be read normally and the servo operation is abnormal,
A first servo operation restoration means is provided for temporarily stopping the tracking servo and the slide servo, moving the optical pickup by a predetermined amount in the inner peripheral direction of the disk-shaped recording medium, and then activating each stopped servo. It has a structure.

Therefore, due to an external shock or the like,
For example, even if the tracking servo or slide servo becomes abnormal, and when the servo is abnormal and the optical pickup is moved significantly to the non-recorded area on the outer circumference side of the disk-shaped recording medium, the optical pickup is restarted. Since it is sometimes pulled back from the non-recorded area and the address information and the like can be read again when the servo is restarted, the reading processing of the music information and the like can be continued without stopping the reproducing operation. As a result, there is an effect that the earthquake resistance of the device is improved.

As described above, the optical disc apparatus according to the second aspect of the present invention determines that the information signal from the disc-shaped recording medium cannot be read normally and that the servo operation is abnormal, and the abnormality is the focus servo operation. If it is determined that the above-mentioned abnormality is detected, all the servo operations are temporarily stopped, the optical pickup is moved in the inner peripheral direction of the disk-shaped recording medium by a predetermined amount, and then all servos are started again. Second servo operation restoration Means are provided.

Therefore, due to an external shock or the like,
Even if the focus servo becomes abnormal and other servo operations become abnormal due to the effect, and the optical pickup is moved significantly and moved outside the disc-shaped recording medium, the optical pickup will still be disc-shaped when it is restarted. Since it has been pulled back onto the recording medium, each servo can be restarted and the address information etc. can be read again, so it is possible to continue reading the music information etc. without stopping the playback operation. You can As a result, there is an effect that the earthquake resistance of the device is improved.

As described above, the optical disk device according to claim 3 of the present invention is the optical disk device according to claim 1 or 2, wherein the first or second servo operation restoration means is
In the case where the disc-shaped recording medium is a recordable / reproducible type, after temporarily stopping each predetermined servo operation, the optical pickup is moved to the innermost position of the disc, and the signal read by the optical pickup is changed to the recording method. The signal processing circuit to be restored accordingly is switched so as to be able to be restored according to the recording method of the disk innermost position, and then each servo is restarted.

Therefore, for example, while reading the lead-in area, a servo operation abnormality occurs and the optical pickup is moved to the music information area (or user TOC area), or conversely, the music information area (or user TOC area). Even if the optical pickup is moved to the lead-in area while reading the music information from the TOC area), the information can be reliably read, so that the music information can be read without stopping the reproducing operation. The reading process can be continuously performed. As a result, there is an effect that the earthquake resistance of the device is further improved.

[Brief description of drawings]

FIG. 1 is a flowchart showing a processing procedure of a music information reading process of a mini disk device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of the mini disk device.

FIG. 3 is an explanatory diagram schematically showing a layout of a reproduction-only MD handled by the above-mentioned mini disk device.

FIG. 4 is an explanatory diagram schematically showing a layout of a recording / reproducing MD handled by the above-mentioned mini disk device.

FIG. 5 is a block diagram showing a schematic configuration of a conventional mini disk device.

FIG. 6 is a flowchart showing a processing procedure of a music information reading process in a conventional mini disk device.

[Explanation of symbols]

1 mini disk (disk recording medium) 1a read-only mini disk 1b recording / reproducing mini disk 2 spindle motor 3 optical pickup 6 lead-in switch 7 changeover switch 10 amplifier 11 signal processing circuit 13 slide servo circuit 14 focus servo circuit 15 tracking servo Circuit 16 Spindle servo circuit 17 System controller (first servo operation restoration means second servo operation restoration means)

Claims (3)

[Claims] 1. Various servo operations such as focus servo, tracking servo, spindle servo and slide servo are carried out in order to capture a specific track on a disk-shaped recording medium by an optical pickup and read an information signal on the track. In the optical disc device, when it is determined that the information signal from the disc-shaped recording medium cannot be read normally and the servo operation is abnormal, the tracking servo and the slide servo are temporarily stopped, and the optical pickup is moved to the inner circumference of the disc-shaped recording medium. An optical disk device comprising: first servo operation restoration means for activating each of the servos that are stopped again after being moved in a predetermined direction. 2. Various servo operations such as focus servo, tracking servo, spindle servo and slide servo are carried out in order to capture a specific track on a disk-shaped recording medium by an optical pickup and read an information signal on the track. In the optical disc device, when it is determined that the information signal from the disc-shaped recording medium cannot be read normally and the servo operation is abnormal, and the abnormality is the focus servo operation abnormal, all the above servo operations are performed. An optical disk apparatus characterized by further comprising a second servo operation restoration means for temporarily stopping the optical pickup and thereafter moving the optical pickup a predetermined amount in the inner peripheral direction of the disk-shaped recording medium, and then reactivating all servos. . 3. The first or second servo operation restoration means, when the disk-shaped recording medium is a recordable / reproducible type,
After temporarily stopping each predetermined servo operation, the optical pickup is moved to the innermost position of the disc, and a signal processing circuit that restores the information signal read by the optical pickup according to the recording method is used. 3. The optical disk device according to claim 1 or 2, wherein each servo is restarted after switching so as to enable restoration according to the recording method of the inner peripheral position.