JP2810279B2 - Optical disk recording and playback device - Google Patents

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 method suitable for an optical disk recording / reproducing apparatus for recording / reproducing a recording mini-disc (MD).

[0002]

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

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

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

In such a conventional optical disk recording / reproducing apparatus, the signal for controlling the rotation of the disk motor is switched at the boundary between the pit portion and the pre-groove portion. However, there is a disadvantage that the rotation of the disk motor becomes unstable because the boundary cannot be detected. Further, when the disk is stopped, a brake current is applied to the disk motor, and a brake signal for that 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 quickly and stably.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical disk recording / reproducing apparatus capable of stopping a disk motor stably and quickly. It is to be.

[0007]

According to the present invention, there is provided an optical disk recording / reproducing apparatus comprising: a first area in which information is recorded by pits of a pit row to which no wobble is applied; and a second area in which address information is recorded by a pregroove. When the rotation of the optical disc is stopped by supplying a brake signal to the disc motor control unit, information is recorded by the pits of the pit row where no wobble is applied in the optical disc recording / reproducing apparatus for recording / reproducing the optical disc having the area of The brake signal is released when the pit information extraction clock cycle becomes longer than a predetermined cycle in the area where the pit information is extracted, and when the cycle of the wobble signal becomes longer than the predetermined cycle in an area having a pre-groove having a waveform including address information. It is something to do.

In the above-mentioned optical disk recording / reproducing apparatus, the pass band of a band-pass filter for extracting a wobble signal when a brake signal is output in an area having a pre-groove having a waveform including address information is extended to a lower frequency side. Things.

[0009]

According to the optical disk recording / reproducing apparatus of the present invention,
When moving the laser spot between the pit portion and the pre-groove portion, the disk motor is rotated by inertia or a constant voltage is input as an error signal of the disk motor servo to control the rotation speed of the disk motor. Since the motor is stopped, the rotation of the disk motor during the search is stabilized.

Further, when the rotation of the optical disk is stopped, in a region where information is recorded by pits of a pit row to which wobble is not applied, when a pit information extraction clock cycle becomes longer than a predetermined cycle, an address information If the brake signal is released when the period of the wobble signal is longer than the predetermined period in the region of the pre-groove having the waveform including, the disk motor is surely decelerated to the predetermined speed, and the disk motor can be stopped quickly. It becomes possible.

In this case, if the pass band of the band-pass filter for extracting the wobble signal is widened to a lower frequency side, it is possible to reliably detect that the disk motor has decelerated to a predetermined speed.

[0012]

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 according to the present invention. 1 is a recordable optical disk. Information about the disk is engraved as a lead-in on the inner periphery of the optical disk 1 by a pit train. No wobble is added to the pit row in this part.

Following the lead-in, a recordable area is provided, and the pregroove is spirally carved. The pre-groove has a waveform and contains FM-modulated address information.

Reference numeral 2 denotes an optical pickup which irradiates a laser beam so as to focus on a disk recording surface so as to track a pit row or a pre-groove, and picks up information from the reflected light. At the time of disk recording, the optical disk 1 is irradiated with laser light 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 a rotating shaft. Reference numeral 4 denotes a preamplifier which amplifies a signal picked up by the optical pickup 2, generates respective error signals required for focus control and tracking control, outputs the error signal to a control circuit 6, and generates an information signal engraved on the optical disk 1. 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, emits the laser diode with a constant power necessary for reading information when reproducing the disk, and heats the optical disk 1 to a magnetically reversible temperature when recording the disk. To emit light at the required constant power.

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

The control circuit 6 receives the error signal from the preamplifier 4, controls the focus and tracking of the optical pickup 1, and controls the rotation of the disk motor 3 in accordance with the disk 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 the CPU 2 to search for a designated address.

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

The signal processing circuit 7 further performs
The 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.

At the time of reproduction, a digital audio signal and 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. 8 is output.

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

The system controller 8 includes a signal processing circuit 7
And controls the operation state of the control circuit 6 while communicating with the control circuit 6 and obtains information engraved on the disk from the signal processing circuit 7 to cause the optical pickup 2 to perform a search operation, a reproduction operation, and a recording operation. Is sent 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 / writes the optical disk 1.
Control circuit 6 to read the optical pickup 2
Is moved to a predetermined location, and then the 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 disk.

Thereafter, 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 signal processing circuit 7
Stops controlling the rotation of the disk by using the rotation speed control error signal generated in the step, sets the disk in a state of inertia rotation, opens the tracking servo and the feed servo of the optical pickup, and sets the optical pickup 2 to a predetermined position. , And is moved outward to a predetermined position in the pre-groove section.

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 included in the pregroove, and to output it to the control circuit 6. The control circuit 6 controls the rotation of the disk again based on the error signal sent from the signal processing circuit 7.

When stopping the rotation of the disk in the pre-groove section, the system controller 8 controls the control circuit 6
After the band of the band-pass filter 5 is broadened below the band at the time of reproduction, the control circuit 6 generates a brake signal and applies it to the disk motor 3.

When the cycle of the wobble signal from the pregroove becomes longer than a predetermined cycle when the speed of the disk motor 3 is decelerated, the control circuit 6 stops the brake signal and stops the drive of the disk motor.

When the rotation of the disk is stopped in the pit portion, the system controller 8 generates a brake signal in the control circuit 6 and applies the brake signal to the disk 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, a signal indicating this is output from the signal processing circuit 7 to the control circuit 6, and the control circuit 6 outputs the brake signal. To stop the drive of the disk motor.

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

[0033]

According to the optical disk recording / reproducing apparatus of the present invention, the rotation control of the data beyond the boundary where the abnormal voltage is applied to the disk motor due to the malfunction of the circuit for generating the screen motor signal between the pit portion and the pre-groove portion. Is better.

When the rotation of the optical disk is stopped, the speed of the disk motor is surely reduced until the predetermined speed is prevented, and the disk motor can be stopped quickly.

[Brief description of the 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]

 Reference Signs List 1 optical disk 2 optical pickup 3 disk 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 (2)

(57) [Claims] 1. An optical disc recording / reproducing apparatus for recording / reproducing an optical disc having a first area in which information is recorded by pits of a pit row to which no wobble is applied and a second area in which address information is recorded by a pre-groove. When the rotation of the optical disk is stopped by supplying a brake signal to the disk motor control unit, the pit information extraction clock cycle becomes longer than the predetermined cycle in the area where information is recorded by the pits of the pit row where no wobble is applied. An optical disk recording / reproducing apparatus which releases the brake signal when the length of the wobble signal becomes longer than a predetermined period when the period of the wobble signal becomes longer than a predetermined period in a region where a pregroove having a waveform including address information is provided. 2. The optical disk recording / reproducing apparatus according to claim 1, wherein a pass band of a band-pass filter for extracting a wobble signal when a brake signal is output in an area having a pre-groove having a waveform including address information is extended to a lower frequency side. apparatus.