JPH0676468A - Optical disk recording and reproducing device - Google Patents

Abstract

PURPOSE:To stabilize the rotation of a disk motor when a laser spot is moved beyond the bondary of a pit part and a pregroup part. CONSTITUTION:When an optical pickup 2 is moved from the pit part to the pregroup part of an opticak disk 1, a system controller 8 stops the rotation control of the disk by a control circuit 6, using an error signal for rotation speed control generated in a signal processing circuit 7 and makes the disk the rotation state due to inertia. Then, the optical pickup 2 is fed to outwardly beyond a prescribed number of track by opening the tracking servo and a feed servo of the optical pickup and is moved to the prescribed place of the pregroup part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk recording / reproducing apparatus, and more particularly to a disk motor control system suitable for an optical disk recording / reproducing apparatus for recording / reproducing a recording mini disk (MD).

[0002]

2. Description of the Related Art In a CD-MO disc which is a recordable optical disc, both the pit portion and the pre-groove portion are wobbled. Therefore, an optical disc recording / reproducing apparatus for recording / reproducing a CD-MO disc uses a wobble signal to produce a disc. The rotation of the motor can be controlled.

However, a recording mini disk (M
In D), since no wobble is added to the pit train, a signal for controlling the rotation of the disc motor must be obtained from the EFM signal in the pit portion.

In the optical disk recording / reproducing apparatus for recording / reproducing such an optical disk, a signal for controlling the rotation of the disk motor is obtained by the EFM signal in the pit portion and the wobble signal in the pre-groove portion.

In such a conventional optical disc recording / reproducing apparatus, the signal for controlling the rotation of the disc motor is switched at the boundary between the pit portion and the pre-groove portion. However, when the laser spot is moved largely by the pickup feed motor. However, there is a drawback that the rotation of the disk motor becomes unstable because the boundary cannot be detected.

A brake current is applied to the disk motor when the disk is stopped, and a brake signal for that purpose is output for a preset time. Therefore, the timing of releasing the brake signal was not appropriate, and the disk motor could not be stopped stably and quickly.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object thereof is to move a laser spot across a boundary between a pit portion and a pre-groove portion. An object of the present invention is to provide an optical disk recording / reproducing device in which the rotation of the disk motor is stable.

Another object of the present invention is to provide an optical disk recording / reproducing apparatus capable of stably and quickly stopping the disk motor.

[0009]

An optical disk recording / reproducing apparatus of the present invention is an optical disk having an area in which information is recorded by pits in a pit row which is not wobbled and an area having a waveform pregroove including address information. In an optical disk recording / reproducing apparatus for recording / reproducing, when a laser spot is moved between the two areas, the disk motor rotational speed control is stopped by a rotational speed error signal obtained from information contained in the optical disk. .

Further, in the optical disc recording / reproducing apparatus, when the rotation of the optical disc is stopped, the pit information extraction clock cycle becomes longer than a predetermined cycle in the area where information is recorded by the pits of the pit row where no wobble is applied. In addition, the brake signal is released when the period of the wobble signal becomes longer than a predetermined period in a region having a pre-groove of a waveform including address information.

Further, in the optical disk recording / reproducing apparatus, the pass band of the band pass filter for taking out the wobble signal when outputting the brake signal in the region having the pre-groove of the waveform including the address information is widened to the low frequency side. It is a thing.

[0012]

According to the optical disk recording / reproducing apparatus of the present invention,
When moving the laser spot between the area of the pit and the pre-groove, the disk motor rotation speed is controlled by rotating the disk motor by inertia or by inputting a constant voltage as an error signal of the disk motor servo. Since it is stopped, the rotation of the disk motor during search is stable.

In addition, when the rotation of the optical disk is stopped, when the pit information sampling clock cycle becomes longer than a predetermined cycle in the area where the information is recorded by the pits of the pit row where the wobble is not applied, the address information is also recorded. If the brake signal is released when the period of the wobble signal becomes longer than the predetermined period in the area with the pre-groove containing the waveform including, the disk motor is reliably decelerated to the predetermined speed, and the disk motor can be stopped quickly. It will be possible.

In this case, if the pass band of the band pass filter for extracting the wobble signal is widened to the low frequency side, it can be surely detected that the disk motor has been decelerated to a predetermined speed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical disk recording / reproducing apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an optical disk recording / reproducing apparatus of the present invention. Reference numeral 1 shown in the figure is a recordable optical disk. On the inner circumference of the optical disc 1, information about the disc is engraved as a lead-in by a pit string. No wobble is added to the pit row in this portion.

A recordable area is provided following the lead-in, and pregrooves are engraved in a spiral shape. The pregroove has a waveform and includes FM-modulated address information.

Reference numeral 2 denotes an optical pickup which irradiates a laser beam so as to focus on the recording surface of the disk so as to trace a pit row and a pre-groove, and picks up information from the reflected light. Further, at the time of disk recording, laser light is emitted at a constant power required to heat the optical disk 1 to a temperature at which magnetic reversal is possible.

Reference numeral 3 denotes a disk motor, which rotationally drives the optical disk 1 clamped on a turntable provided on the rotary shaft. Reference numeral 4 denotes a preamplifier, which amplifies the signal picked up by the optical pickup 2, generates respective error signals necessary for focus control and tracking control, outputs the error signals to the control circuit 6, and generates an information signal engraved on the optical disc 1. Then, the wobble signal from the pre-groove is generated and output to the signal processing circuit 7 and the control circuit 6 via the band pass filter 5.

The preamplifier 4 further drives the laser diode of the optical pickup 2 so that the laser diode emits light with a constant power required for reading information when reproducing the disk, and the optical disk 1 is heated to a temperature capable of magnetic reversal when recording the disk. It emits light with the constant power required for.

The bandpass filter 5 is 2 during normal reproduction.
The band is about 2.05 kHz ± 5 kHz, and when the disk motor is stopped, the band is switched to about 12 kHz ± 5 kHz by a command from the control circuit 6.

The control circuit 6 receives the error signal from the preamplifier 4 to control the focus and tracking of the optical pickup 1 and controls the rotation of the disc motor 3 in accordance with the disc rotation control signal from the signal processing circuit 7. The control circuit 6 further includes a system controller 8
The optical pickup 2 is moved in response to a command from to search for a designated address.

The signal processing circuit 7 generates a disc rotation control signal from the pit information extraction clock cycle in the pit row portion, and generates a disc rotation control signal from the wobble signal in the pre-groove portion and outputs it to the control circuit 6. .

The signal processing circuit 7 further adds
Recording information is generated from the digital audio signal input from the A / D converter 12 and the sub data input from the system controller 8 and output to the magnetic head drive circuit 9.

During reproduction, the digital audio signal and the sub data are demodulated from the signal from the preamplifier 4 and output to the D / A converter 11 and the system controller 8, respectively, and further the address information is demodulated from the wobble signal to the system controller. Output to 8.

The magnetic head drive circuit 9 supplies a current according to the recording information input from the signal processing circuit 7 to the magnetic head 10.
Supply to. The magnetic head 10 vertically applies a magnetic field according to recorded information to the optical disc 1.

The system controller 8 is a signal processing circuit 7
Also, the operating state of the control circuit 6 is controlled while communicating with the control circuit 6, and information engraved on the disc is obtained from the signal processing circuit 7 to cause the optical pickup 2 to perform a search operation, a reproduction operation, and a recording operation. To the control circuit 6 and the signal processing circuit 7.

When the optical disk recording / reproducing apparatus is started, the system controller 8 reads the optical disk 1
In order to read the in-information, the control circuit 6 has an optical pickup 2
After moving to a predetermined place, focus servo, tracking servo and feed servo of the optical pickup are applied, and the rotation control error signal is sent to the signal processing circuit 7 so that the transmission rate of the EFM signal becomes a predetermined rate. It is generated and output to the control circuit 6.

In this state, the system controller 8 receives the signal decoded by the signal processing circuit 7 and recognizes the contents of the disc.

After that, when the optical pickup 2 is moved from the pit portion of the optical disc 1 to the pre-groove portion,
The system controller 8 includes a control circuit 6 and a signal processing circuit 7
The rotation control of the disc is stopped by using the error signal for controlling the rotation speed generated in step 3, the disc is set to the inertial rotation state, the tracking servo and the feed servo of the optical pickup are opened, and the optical pickup 2 is set to a predetermined position. The number of tracks is exceeded and it is sent to the outside and moved to a predetermined position in the pre-groove part.

Then, the tracking servo and the feed servo are closed, and the system controller 8 causes the signal processing circuit 7 to generate an error signal for controlling the rotation of the disk from the wobble information contained in the pregroove and output it to the control circuit 6. The control circuit 6 again controls the rotation of the disk according to the error signal sent from the signal processing circuit 7.

When the rotation of the disc is stopped in the pregroove portion, the system controller 8 controls the control circuit 6
Then, the band of the band pass filter 5 is widened at a lower side than the band at the time of reproduction, and then a brake signal is generated in the control circuit 6 to be applied to the disk motor 3.

When the disc motor 3 decelerates and the period of the wobble signal from the pre-groove becomes longer than a predetermined period, the control circuit 6 stops the brake signal and stops the drive of the disc motor.

When stopping the rotation of the disc in the pit portion, the system controller 8 causes the control circuit 6 to generate a brake signal and apply it to the disc motor 3.

When the disk motor 3 decelerates and the transmission rate of the EFM signal from the pit train becomes lower than a predetermined rate, the signal processing circuit 7 outputs a signal indicating this to the control circuit 6 and the control circuit 6 outputs a brake signal. To stop the drive of the disk motor.

In this way, the rotation of the disc motor can be stabilized even when the laser spot is moved across the boundary between the pit portion and the pre-groove portion, and the disc motor can be stopped stably and quickly.

The embodiment is configured as described above, but the invention is not limited to this. For example, when the laser spot is moved beyond the boundary between the pit portion and the pre-groove portion, the disk motor is rotated by inertia. Alternatively, a predetermined voltage or a voltage obtained by integrating a rotation error signal may be applied to the disk motor.

[0037]

According to the optical disk recording / reproducing apparatus of the present invention, an abnormality occurs due to a malfunction of a circuit for generating a disk motor rotation control error signal when moving a laser spot across a boundary between a pit portion and a pre-groove portion. Is applied to the disk motor, the rotation of the disk motor is stabilized, and the rotation control of the disk motor after the search is easily performed.

Further, when the rotation of the optical disk is stopped, the disk motor is surely decelerated to a predetermined speed, and the disk motor can be stopped quickly.

[Brief description of drawings]

FIG. 1 is a block diagram showing an optical disc recording / reproducing apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 1 Optical Disc 2 Optical Pickup 3 Disc Motor 4 Preamplifier 5 Bandpass Filter 6 Control Circuit 7 Signal Processing Circuit 8 System Controller 9 Magnetic Head Drive Circuit 10 Magnetic Head 11 D / A Converter 12 A / D Converter

Claims (3)

[Claims] 1. An optical disk recording / reproducing apparatus for recording / reproducing an optical disk having an area in which information is recorded by pits of a pit row in which no wobble is applied and an area in which a pregroove having a waveform including address information is present, is used. An optical disk recording / reproducing apparatus characterized in that, when moving between two areas, a disk motor rotation speed control by a rotation speed error signal obtained from information contained in the optical disk is stopped. 2. When the rotation of the optical disc is stopped, when the pit information sampling clock cycle becomes longer than a predetermined cycle in the area where the information is recorded by the pits of the pit row where the wobble is not applied, the address information is also recorded. 2. The optical disk recording / reproducing apparatus according to claim 1, wherein the brake signal is released when the period of the wobble signal becomes longer than a predetermined period in a region having a pre-groove having a waveform including ". 3. The optical disk recording / reproducing according to claim 2, wherein a pass band of a band pass filter for extracting a wobble signal when a brake signal is output in a region having a pre-groove of a waveform including address information is widened to a low frequency side. apparatus.