JPH11162102A - Optical disk apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk apparatus capable of surely performing various servo operations. SOLUTION: An optical disk apparatus is a CD-R drive apparatus for recording and reproducing an optical disk (CD-R) and capable of rotating the optimal disk at multiple stages of revolution (rotational speed). This optical disk apparatus is configured so that when the number of revolutions of the optical disk is to be set at a first target value from a stop condition of the optical disk, the number of revolutions of the optical disk is temporally controlled to be a second target value and then various servo operations, such as a focus control, a tracking control, a thread control and the like, and various auto-matic adjustments, such as a calibration (an adjustment of an amplitude of a signal), an adjustment of a signal reference level for canceling (reducing) an offset, and the like, are performed during a time period of t0-t1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk apparatus for reproducing or recording / reproducing an optical disk.

[0002]

2. Description of the Related Art An optical disk device for reproducing or recording / reproducing an optical disk (for example, CD-R drive device, CD
-ROM drive devices and the like) are known.

In an optical disk device, for example, when the optical disk is restarted after the rotation is stopped, the focus servo, the tracking servo, and the servo are accelerated so that the rotation speed (rotation speed) of the optical disk becomes the same as before the stop. Performs various servo controls such as thread servo. In addition, high speed reproduction is becoming mainstream in optical disk devices.

However, an eccentric (bad center of gravity) bad optical disk is circulating, and if acceleration is performed to rotate such a poor optical disk at a high speed, a good optical disk is rotated at a high speed. In comparison, the vibration of the optical disk device is large, that is, the vibration of the optical head (optical pickup) is large, so that various servos, particularly, focus servo and tracking servo may not be applied.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical disk apparatus capable of performing various servo operations reliably.

[0006]

This and other objects are achieved by the present invention which is defined below as (1) to (8).

(1) A rotation drive mechanism for mounting and rotating an optical disk, an optical head having an objective lens, signal processing means for processing a signal read from the optical disk by the optical head, and at least the rotation drive mechanism An optical disc device for controlling the driving of an optical head and a signal processing means, wherein the optical disc apparatus reproduces or records / reproduces the optical disc. Converging the rotation speed of the optical disc to a second target rotation speed lower than the first target rotation speed, and then setting the rotation speed to the first target rotation speed; and
An optical disk device, wherein at least drive control of the objective lens is performed until the rotation speed of the optical disk converges to the second target rotation speed.

(2) A rotation drive mechanism for mounting and rotating an optical disk, an optical head having an objective lens, signal processing means for processing a signal read from the optical disk by the optical head, and at least the rotation drive mechanism An optical head device for controlling the driving of an optical head and a signal processing unit, and for reproducing or recording / reproducing the optical disk, wherein the rotation speed of the optical disk is set to a first target value from a stopped state of the optical disk. When the rotation speed is set, the rotation speed of the optical disk is made to converge to a second target rotation speed lower than the first target rotation speed, and thereafter, the rotation speed of the optical disk is set to the first target rotation speed. A light source configured to perform at least drive control of the objective lens before converging to the second target rotation speed; Disk device.

(3) When the first target rotation speed exceeds a reference value, the rotation speed of the optical disc is made to converge on the second target rotation speed. An optical disk device according to claim 1.

(4) The average acceleration from the second target rotation speed to the first target rotation speed is larger than the average acceleration of the rotation speed of the optical disk up to the second target rotation speed. The optical disc device according to any one of (1) to (3), configured as described above.

(5) The optical disc device according to any one of (1) to (4), wherein the drive control of the objective lens is at least one of focus control and tracking control.

(6) The above-mentioned (1), wherein the feed control of the optical head is further performed until the rotation speed of the optical disk converges to the second target rotation speed.
The optical disc device according to any one of (1) to (5).

(7) The above (1) to (6), wherein the signal is further initialized before the rotation speed of the optical disk converges to the second target rotation speed.
An optical disc device according to any one of the above.

(8) The optical disk device according to (7), wherein the initialization of the signal is at least one of adjustment of the amplitude of the signal and adjustment of the reference level of the signal.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical disk device and an inspection method of the optical disk device according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a block diagram showing a state in which the optical disk device of the present invention is connected to a computer, and FIG. 2 is a block diagram showing an embodiment of the optical disk device of the present invention.

The optical disk device 1 shown in these figures is a CD-R drive device for recording and reproducing an optical disk (CD-R) 2.

A spiral pre-groove (WOBBLE: not shown) is formed on the optical disc 2.

The pre-groove meanders at a predetermined cycle (22.05 kHz at 1 × speed), and the pre-groove has an ATIP (Absolute Time In Pre-Groove).
) Information (time information) is recorded. In this case, A
The TIP information is bi-phase modulated.
It is FM-modulated and recorded at a carrier frequency of 05 kHz.

The pregroove functions as a guide groove when forming pits / lands on the optical disc 2 (pit / land recording). Also, this pre-groove is played,
It is used for controlling the rotation speed of the optical disk 2 and specifying the position (absolute time) on the optical disk 2.

The optical disk device 1 includes a turntable and a spindle motor 8 for rotating the turntable.
It has a rotation drive mechanism (not shown) for mounting the optical disk 2 on the turntable and rotating it. This rotation drive mechanism operates the optical disc 2 at a plurality of rotation speeds (rotation speeds).
To rotate. In the vicinity of the spindle motor 8,
A hall element 9 is provided.

The optical disk apparatus 1 has an optical head (optical pickup) 3 that can move in the radial direction of the optical disk 2 (radial direction of the turntable) with respect to the loaded optical disk 2 (turntable), and An optical head main body moving mechanism (not shown) including a sled motor 5 for moving the head 3 in the radial direction, that is, an optical head main body (optical pickup base) of the optical head 3 described later in the radial direction, and drivers 6 and And PWM
Signal smoothing filters 7 and 12, control means 13,
A laser control unit 14, an HF signal generation circuit 15, an HF signal gain switching circuit 16, a peak / bottom detection circuit 17, an error signal generation circuit 18, a WOBBLE signal detection circuit 19, a CD servo controller 21, a WO
BBLE servo controller 22, FG signal binarization circuit 23, EFM / CDROM encoder control unit 24
, Memories 25, 26 and 29, a sync signal generation / ATIP decoder 27, a CDROM decoder control unit 28, an interface control unit 31, a clock 3
2, 33, 34 and 35 and a casing 10 for accommodating them. Hereinafter, the radial direction of the optical disk 2 is simply referred to as “radial direction”.

The optical head 3 includes an optical head body (optical pickup base) (not shown) provided with a laser diode (light source) and a split photodiode (light receiving element).
An objective lens (condensing lens). The driving of the laser diode is controlled by the laser controller 14.

The objective lens is supported by a suspension spring (not shown) provided on the optical head main body, and can move in the radial direction and the rotation axis direction of the optical disk 2 (turntable) with respect to the optical head main body. ing. When the objective lens deviates from its neutral position (middle point), the objective lens is urged toward the neutral position by the restoring force of the suspension spring. Hereinafter, the direction of the rotation axis of the optical disc 2 will be simply referred to as “the direction of the rotation axis”.

The optical head 3 has an actuator 4 for moving the objective lens in the radial direction and the rotation axis direction with respect to the optical head body.

The control means 13 is usually constituted by a microcomputer (CPU), and comprises an optical head 3 (actuator 4), a sled motor 5, a spindle motor 8, a laser control unit 14, an HF signal gain switching circuit 16, a peak / bottom Detection circuit 17, CD servo controller 2
1, WOBBLE servo controller 22, EFM / C
DROM encoder control unit 24, memories 25 and 26,
29, sync signal generation / ATIP decoder 27, CDR
OM decoder control unit 28, interface control unit 31
For example, the entire optical disk device 1 is controlled.

The address, data, and COMMAN are sent from the control means 13 via the address / data bus 36.
D (command) and the like are input to the EFM / CDROM encoder control unit 24, the memory 26, the sync signal generation / ATIP decoder 27, the CDROM decoder control unit 28, the interface control unit 31, and the like.

An external device (computer 41 in this embodiment) is detachably connected to the optical disk device 1 via an interface control section 31 so that communication between the optical disk device 1 and the computer 41 can be performed. it can.

The interface control unit 31 includes, for example, ATAPI (IDE) (Attape standard), SC
SI (squay standard) or the like is used.

The computer 41 has a keyboard 4
2. The mouse 43 and the monitor 44 are connected respectively.

The transmission means is constituted by the interface control section 31. HF signal generation circuit 1
5, HF signal gain switching circuit 16, peak / bottom detection circuit 17, error signal generation circuit 18, WOBBLE
The signal detection circuit 19, the CD servo controller 21 and the WOBBLE servo controller 22 constitute a signal processing unit.

Next, the operation of the optical disk device 1 will be described. The optical disc device 1 records information (data) on the optical disc 2 while performing focus control, tracking control, thread control (optical head feed control), and rotation speed control (rotation speed control) on a predetermined track. Write) and playback (read). Hereinafter, recording, reproduction, focus control, tracking control and thread control (optical head feed control),
The operation at the time of rotation speed control (rotation speed control) will be described.

First, as a premise, as shown in FIG. 2, a predetermined COMMAND signal is input from the control means 13 to the CD servo controller 21. Control means 1
From 3, a predetermined COMMAND signal is input to the WOBBLE servo controller 22.

This COMMAND signal is supplied to the control means 13
Is a signal indicating a predetermined command (for example, start of control, etc.) to the CD servo controller 21 or the WOBBLE servo controller 22 from the controller.

Then, a predetermined STATUS signal is input to the control means 13 from the CD servo controller 21. Further, a predetermined STATUS signal is input from the WOBBLE servo controller 22 to the control means 13.

The STATUS signal is a signal indicating a response to the command, that is, information indicating the control (for example, each status such as control success, control failure, and control execution).

[Recording] Recording (writing) data (signal) on the optical disc 2
At this time, the pre-groove formed on the optical disc 2 is reproduced (read), and thereafter, data is recorded along the pre-groove.

When data (signal) to be recorded on the optical disk 2 is input to the optical disk device 1 via the interface control unit 31, the data is transmitted to the EFM / CRO.
It is input to the M encoder control unit 24.

In the EFM / CDROM encoder control section 24, the data is encoded (at the timing of the clock signal) based on the clock signal from the clock 34, and is modulated by a modulation method called EFM (Eight to Fourteen Modulation). EFM modulation) and ENC
This is an ORDE EFM signal.

As shown in FIG. 3, this ENCODE
The EFM signal is a signal composed of pulses having a length (period) of 3T to 11T.

As shown in FIGS. 4 and 5, EF
In the M / CDROM encoder control unit 24, the clock 3
4 is divided to generate a SUBCODE-SYNC signal (subcode sync signal) composed of pulses of a predetermined cycle. This SUBCODE-SY
Cycle of NC signal pulse (interval between adjacent pulses)
Is 1/75 second at 1 × speed.

At the time of the encoding, a synchronization signal, that is, a SYNC pattern (sync pattern) is transmitted to the SU.
Based on the BCODE-SYNC signal (SUBCODE
-At the timing of the SYNC signal), the ENCODE
It is added to the EFM signal. That is, SYNC is added to the portion corresponding to the head of each subcode frame.
A pattern is added.

This ENCODE EFM signal is output from the EF
The data is input from the M / CDROM encoder control unit 24 to the laser control unit 14.

The WRITE P which is an analog signal
An OWER signal (voltage) is output from a D / A converter (not shown) built in
Is input to

The laser control section 14 has an ENCODE E
On the basis of the FM signal, the WRITE
The level of the POWER signal is switched between a high level (H) and a low level (L) and output, whereby the driving of the laser diode of the optical head 3 is controlled.

Specifically, the laser control unit 14
While the level of the ORDE EFM signal is high (H), the level of the WRITE POWER signal is set to high (H) and output. That is, the output of the laser is increased (write output). And ENCODE
While the level of the EFM signal is low (L), the WRI
The level of the TE POWER signal is set to a low level (L) and output. That is, the output of the laser is reduced (return to read output).

As a result, the optical disk 2 has an ENCO
When the level of the RDE EFM signal is high (H), a pit of a predetermined length is written, and ENCODE EFM is written.
When the level of the FM signal is low (L), a land of a predetermined length is written.

In this manner, data is written (recorded) on a predetermined track of the optical disc 2.

EFM / CDROM encoder control unit 24
In, a predetermined ENCODE EFM signal (random EFM signal) is generated in addition to the above-mentioned ENCODE EFM signal. This random EFM signal is output from the OPC (Opti
mum Power Control) is used for laser output adjustment (power control) at the time of test writing to the test area.

At the time of test writing to a test area in OPC, the random EFM signal
The data is input from the M encoder control unit 24 to the laser control unit 14.

At the time of trial writing in the test area in the OPC, the control means 13 generates a WRITE POWER signal of 15 levels and outputs the WRITE POWER signal.
The EPOWER signal is output from a D / A converter (not shown) built in the control unit 13 and input to the laser control unit 14.

Then, the laser control unit 14 receives the WRIT from the control unit 13 based on the random EFM signal.
The level of the E POWER signal is switched between a high level (H) and a low level (L) and output, thereby controlling the driving of the laser diode of the optical head 3. This is performed for each of the WRITE POWER signals of 15 levels.

In the OPC operation, the test writing to the test area is performed with the laser light having the 15-step output in this manner.

When writing data to the optical disk 2, a laser beam of read output is irradiated from the laser diode of the optical head 3 to the pregroove of the optical disk 2, and the reflected light is received by the divided photodiode of the optical head 3. Is done.

The split photodiode outputs a WOBBLE signal shown in FIG. As described above, the WOBBLE signal includes a signal having a frequency of 22.05 kHz at 1 × speed, and a signal obtained by performing biphase modulation on ATIP information and further performing FM modulation at a carrier frequency of 22.05 kHz.

The WOBBLE signal is input to the WOBBLE signal detection circuit 19, and is binarized by the WOBBLE signal detection circuit 19.

The binarized WOBBLE signal is the WOB signal.
This is input to the BLE servo controller 22.

In the WOBBLE servo controller 22, the FM-modulated AT of the WOBBLE signal is used.
The IP information is demodulated to obtain a BIDATA signal (bi-phase data signal) shown in FIG. This BIDATA signal is a signal (pulse signal) of 1T to 3T. Note that this BIDATA signal is bi-phase demodulated and then decoded to obtain ATIP information.

The WOBBLE servo controller 2
2, a digital PLL circuit (not shown) generates a clock based on the BIDATA signal,
The BICLOCK signal shown in FIG. 7 is obtained. This BICLO
The CK signal is used for decoding timing of a BIDATA signal described later.

The BIDATA signal and the BICLOC
The K signals are input to the sync signal generation / ATIP decoder 27, respectively.

The sync signal generation / ATIP decoder 27 bi-phase demodulates the BIDATA signal based on the BICLOCK signal, and then decodes and decodes the ATIP signal.
Information is obtained, and an ATIP-SYNC signal (ATIP sync signal) shown in FIG. 7 is generated.

In this case, as shown in FIG.
When a SYNC pattern included in the A signal is detected, a pulse of the ATIP-SYNC signal is generated. The period of the pulse of the ATIP-SYNC signal (the interval between adjacent pulses) is 1/75 second at 1 × speed.

This ATIP-SYNC signal is input to each of the control means 13 and the WOBBLE servo controller 22.

The decoded ATIP information is input to the control means 13. The control means 13 grasps the absolute time on the optical disc 2 based on the ATIP information.

The SUBCODE-SYNC signal from the EFM / CDROM encoder control unit 24 is input to the sync signal generation / ATIP decoder 27, and the sync signal generation / ATIP decoder 27 sends the SUBCODE-SYNC signal to the control unit 13.
And WOBBLE servo controller 22.

FIG. 8 is a diagram showing the format of an ATIP frame. As shown in the figure, the data of the ATIP frame is a 4-bit synchronization signal, that is, a sync (S
yn), an 8-bit minute (Min), an 8-bit second (Sec), an 8-bit frame, and a 14-bit error detection code (CRC: Cyclic Redundancy Code).

The WOBB servo controller 22 detects an error in the ATIP information for each ATIP frame (determines whether the ATIP information is incorrect).

In this error detection of the ATIP information, the ATI
"Normal" means that the result of performing a predetermined operation on the Sync, minute (Min), second (Sec) and frame data of the P frame matches the error detection code (CRC), Say "ATIP error."

In this case, as shown in FIG.
In the E servo controller 22, an error in the ATIP information,
That is, when an ATIP error is detected, a pulse 51 is generated and output.

ATIP E composed of this pulse 51
The RROR signal is input to a counter (counter) 131 of the controller 13. And this counter 13
1, the number of pulses of the ATIP ERROR signal becomes A
It is counted (measured) as a TIP error.

The error detection of the ATIP information is performed by the ATIP
Since it is performed for each frame, the ATIP error is 75 A
There are a maximum of 75 TIP frames (1 second at 1 × speed).

The WOBBLE servo controller 2
2 constitutes a detecting means for detecting an ATIP error.

The count value of the ATIP error is stored in the memory 26 and the interface control unit 3
1 and transmitted to the computer 41 for use in the inspection of the optical disk device 1 (determination of the recording capability of the optical disk device 1).

The ATIP-input to the control means 13
The SYNC signal is used for updating the ATIP time information.

The WOBBLE servo controller 2
2, the ATIP-SYNC signal is input to the SUBCO
Used for synchronization with the DE-SYNC signal.

SUBCODE input to the control means 13
The -SYNC signal is used for interpolation of ATIP time information and measurement of the ATIP error described above.

The WOBBLE servo controller 2
The SUBCODE-SYNC signal input to 2 is used as a reference signal for synchronization, like the ATIP-SYNC signal.

The synchronization is performed in order to make the position of the SUBCODE-SYNC signal in the EFM data generated at the time of writing substantially coincide with the position of the ATIP-SYNC signal on the optical disk 2 where the ATIP-SYNC signal is generated.

As shown in FIG. 9, SUBCODE-SY
The difference between the NC signal and the ATIP-SYNC signal is usually
± 2E at each part of the entire optical disc 2
Up to FM frames are allowed.

[Reproduction] When reproducing (reading) data (signal) from the optical disk 2, the WRITE POW from the laser control unit 14 is used.
The level of the ER signal is a constant D corresponding to the read output.
The output is held at the C level, whereby the output of the laser is held at the read output. The read output (output of the main beam) is usually set to 0.7 mW or less.

When reading data from the optical disk 2,
A read output laser beam is radiated from a laser diode of the optical head 3 onto a predetermined track of the optical disc 2,
The reflected light is received by the split photodiode of the optical head 3.

Each light receiving portion of the divided photodiode outputs a current (voltage) corresponding to the amount of received light. These currents, that is, each signal (detection signal) is
Each is input to the HF signal generation circuit 15 and the error signal generation circuit 18.

The HF signal generation circuit 15 generates an HF (RF) signal by adding or subtracting these detection signals.

The HF signal is an analog signal corresponding to the pits and lands written on the optical disk 2.

The HF signal is input to the HF signal gain switching circuit 16 and is amplified. The amplification factor (gain) of the HF signal gain switching circuit 16 is
Is switched by a gain switching signal from the controller.

The amplified HF signal (hereinafter simply referred to as “HF signal”
Signal) is input to each of the peak / bottom detection circuit 17 and the CD servo controller 21.

The peak / bottom detection circuit 17
A tracking error (TE) signal described in the focus control, tracking control, and sled control is input.

As shown in FIG. 10, the peak / bottom detection circuit 17 extracts an amplitude (envelope) of an input signal, for example, an HF signal or a tracking error signal.

The upper side of the amplitude is called PEEK (TOP), the lower side of the amplitude is called BOTTOM, the signal corresponding to the upper side of the amplitude is called the PEEK (TOP) signal, and the signal corresponding to the lower side of the amplitude is called the BOTTOM signal.

The PEEK signal and the BOTTOM signal are
A (not shown) built in the control means 13
The signal is input to a / D converter, and is converted into a digital signal by the A / D converter.

The PEEK signal and the BOTTOM signal are used for, for example, amplitude measurement, amplitude adjustment of a tracking error signal, and β in OPC (Optimum Power Control).
It is used for calculating (β value), determining the presence or absence of an HF signal, and the like.

In the CD servo controller 21, the HF signal is binarized, EFM demodulated, and an EFM signal is obtained. This EFM signal is a signal composed of pulses having a length (period) of 3T to 11T.

The CD servo controller 21 responds to this EFM signal by a CIRC (Cross Interl
Error correction (CIRC error correction) using an error correction code called “eaved Read Solomon Code” is performed twice.

In this case, the first CIRC correction is called C1 error correction, and the second CIRC correction is called C2 error correction.

A case where the first CIRC correction, ie, the C1 error correction cannot be performed, is referred to as “C1 error”, and a case where the second CIRC correction, ie, the C2 error correction cannot be performed, is referred to as “C2 error”.

As shown in FIG. 11, in the CD servo controller 21, when a C1 error is detected during the C1 error correction, a pulse 52 is generated and output.

C1 ERROR constituted by this pulse 52
The R signal is input to the counter 131 of the control means 13. The counter counts (measures) the number of pulses of the C1ERROR signal as a C1 error.

Since one subcode frame is composed of 98 EFM frames, the C1 error and the C2 error are
75 subcode frames each (1 second at 1x speed)
, There are a maximum of 7,350.

The CD servo controller 21 constitutes detecting means for detecting a C1 error.

The count value of the C1 error is stored in the memory 26.
Is transmitted to the computer 41 via the interface control unit 31 and is used for the inspection of the optical disk device 1 (determination of the reproduction capability or the recording / reproduction capability of the optical disk device 1).

In the CD servo controller 21, the CIR
The EFM signal after the C error correction is decoded (converted) into data of a predetermined format, that is, a DATA signal.

Hereinafter, representatively, audio data (music data) is recorded on the optical disc 2 and its EFM
A case where a signal is decoded into a DATA signal in an audio format will be described.

FIG. 12 is a timing chart showing the audio format DATA signal, LRCLOCK signal and BITCLOCK signal.

As shown in the figure, in the CD servo controller 21, the EFM signal is composed of 16-bit L channel data and 16-bit R channel data based on the clock signal from the clock 33.
Decoded to ATA signal.

In the CD servo controller 21,
BITC based on the clock signal from clock 33
A LOCK signal and an LRCLOCK signal are generated, respectively. This BITCLOCK signal is a serial data transfer clock.

The LRCLOCK signal is a signal for distinguishing between L channel data and R channel data in the DATA signal. In this case, when the level of the LRCLOCK signal is high (H), it indicates L channel data, and when it is low (L), it indicates R channel data.

Even when ordinary data is recorded on the optical disk 2, the EFM signal is decoded into the above-mentioned DATA signal composed of 16-bit L channel data and 16-bit R channel data. .

The DATA signal, LRCLOCK signal and BITCLOCK signal are respectively
The data is input to the decoder control unit 28.

In the CDROM decoder control section 28, correction information such as ECC (Error Correc
If an error correction code of (Edtion Code) / EDC (Error Detecting Code) is recorded, the error correction is performed on the DATA signal.

This ECC / EDC is a CD-ROM M
This is an error correction code in the ODE1 format.
By this error correction, the bit error rate can be reduced to about 10 ⁻¹² .

In the CDROM decoder control unit 28, the DATA signal is decoded into data of a predetermined format for communication (transmission) based on the clock signal from the clock 35, and the decoded data (decoded data) Is transmitted to the computer 41 via the interface control unit 31.

On the computer 41 side, for example, the decoded data is encoded, and the encoded data (encoded data) is recorded (copied) on a predetermined recording medium (for example, an optical disk).

In the CD servo controller 21,
The FRAME SYNC signal shown in FIG. 13 is generated.

The level of the FRAME SYNC signal becomes a high level (H) when the HF signal is input to the CD servo controller 21 and the EFM signal is synchronized at a specified period (3T to 11T). And HF
When a signal (EFM signal) is not input (when synchronization is lost), FRAME S is output in EFM frame units.
The level of the YNC signal changes from a high level (H) to a low level (L).

The length (period) of one EFM frame
Is 136 μsec at 1 × speed, and 98 EFM frames are one subcode frame.

The FRAME SYNC signal is input to the control means 13 and used for detecting the end of the HF signal.

The SUBQ DATA signal is input from the CD servo controller 21 to the control means 13.

This SUBQ DATA signal is a signal indicating Q data of the subcode data.

The subcodes include P, Q, R, S, T,
There are eight types, U, V and W. One EFM frame has one byte of subcode, and one byte of each of the data P to W is recorded in one byte.

Each data of P to W is 1 bit, and one subcode frame is a 98 EFM frame. Therefore, each data of P to W in one subcode frame is 98 bits. However, the first 2EF
Since the M frame is used for a SYNC pattern (synchronization signal), the actual data is 96 bits.

FIG. 14 is a diagram showing a format of 96 bits of Q data. The controls (4 bits) of Q1 to Q4 shown in FIG. 6 are used for discriminating normal data / audio data.

Addresses Q5 to Q8 (4 bits)
Indicates the contents of data (72 bits) from Q9 to Q80.

The CRC (Cyclic R) of Q81 to Q96
The edundancy code (16 bits) is used for error (error) detection (determination of whether or not data is incorrect).

From the Q data, the absolute time information on the optical disk 2, the current track information, the lead-in, the lead-out, the music number, and the table of contents called TOC (Table Of Contents) recorded in the lead-in are further obtained. Contents and the like can be obtained.

The control means 13 obtains information from such Q data and performs predetermined control.

The SUBCODE-SYNC signal is input from the CD servo controller 21 to the control means 13.

As shown in FIG. 15, there are 98 bytes of subcode data in the 98 EFM frame. As described above, the two bytes of the first 2 EFM frames, ie, S0 and S1, have a SYNC pattern (synchronous signal). ) Is recorded.

In the CD servo controller 21, this S
When the YNC pattern is detected, a pulse is generated and output. That is, one subcode frame (98EF)
For every M frames), a pulse is generated and output. The signal composed of this pulse is SUBCODE-SYN
This is the C signal. The SYNC pattern is detected 75 times per second at 1 × speed.

In the CD servo controller 21,
After detecting the pulse of the SUBCODE-SYNC signal, the above-described Q data is updated. Then, the updated Q data is read into the control means 13.

[Focus control, tracking control and sled control (optical head feed control)]

The error signal generating circuit 18 performs addition or subtraction of the detection signals from the divided photodiodes described above, thereby obtaining a focus error (FE) signal, a tracking error (TE) signal, and a thread error (SE) signal.
Signals are respectively generated.

This focus error signal is a signal indicating the magnitude and direction of the shift of the objective lens from the focus position in the direction of the rotation axis (the shift amount of the objective lens from the focus position).

The tracking error signal is a signal indicating the magnitude of the displacement of the objective lens in the radial direction from the center of the track (pre-groove) and its direction (the amount of displacement of the objective lens from the center of the track).

The thread error signal is an error (error) signal used for thread control, that is, thread servo (feed servo of the optical head body of the optical head 3). In other words, it is a signal indicating the magnitude and direction of the displacement of the optical head 3 in the radial direction (the feed direction of the optical head 3) from the target position (proper position) of the optical head 3. The focus error signal is input to the CD servo controller 21.

The tracking error signal is input to the CD servo controller 21 and also to the peak / bottom detection circuit 17 as described above. The thread error signal is output from the CD servo controller 2
1 is input.

Using the focus error signal, tracking error signal and thread error signal, the optical disc device 1 performs focus control, tracking control and thread control on a predetermined track.

At the time of focus control, the CD servo controller 21 performs focus PWM (Puls Width Modulation) control for driving the actuator 4 in the rotation axis direction.
) A signal is generated. This focus PWM signal is
It is a digital signal (continuous pulse).

The focus PWM signal is input from the CD servo controller 21 to the PWM signal smoothing filter 7, and is smoothed by the PWM signal smoothing filter 7, that is, converted into a control voltage (control signal).
Is input to Then, the driver 6 applies a focus signal (predetermined voltage) to the actuator 4 based on the control voltage, and drives the actuator 4 in the rotation axis direction (focus direction).

In this case, the CD servo controller 21
Is to adjust the pulse width (duty ratio) of the focus PWM signal and invert the sign (positive or negative) of the focus PWM signal so that the level of the focus error signal becomes 0 (as much as possible). I do. Thereby, the objective lens of the optical head 3 is located at the focus position.
That is, focus servo is applied.

In the tracking control, the CD servo controller 21 generates a tracking PWM signal for controlling the radial driving of the actuator 4.
This tracking PWM signal is a digital signal (continuous pulse).

The tracking PWM signal is input from the CD servo controller 21 to the PWM signal smoothing filter 7, and smoothed by the PWM signal smoothing filter 7.
That is, it is converted into a control voltage (control signal) and input to the driver 6. The driver 6 applies a tracking signal (predetermined voltage) to the actuator 4 based on the control voltage, and drives the actuator 4 in the radial direction (tracking direction).

In this case, the CD servo controller 21
The tracking PWM is adjusted so that the level of the tracking error signal becomes zero (as much as possible).
The pulse width (duty ratio) of the signal is adjusted, and the sign (positive or negative) of the tracking PWM signal is inverted. Thereby, the objective lens of the optical head 3 is located at the center of the track (pre-groove). That is, tracking servo is applied.

At the time of thread control, the CD servo controller 21 generates a thread PWM signal for controlling the drive of the thread motor 5. This thread PW
The M signal is a digital signal (continuous pulse).

The thread PWM signal is input from the CD servo controller 21 to the PWM signal smoothing filter 7, smoothed by the PWM signal smoothing filter 7, that is, converted into a control voltage (control signal) and input to the driver 6. You. The driver 6 sends a sled signal (predetermined voltage) to the sled motor 5 based on the control voltage.
To drive the thread motor 5 to rotate.

In this case, the CD servo controller 21
Is to adjust the pulse width (duty ratio) of the thread PWM signal and to reverse the sign (positive / negative) of the thread PWM signal so that the level of the thread error signal becomes 0 (as much as possible). I do. Thereby, the optical head main body of the optical head 3 is located at the target position (appropriate position). That is, the thread servo is applied.

Incidentally, in addition to tracking control, the tracking error signal is generated by, for example, connecting the optical head 3 to the optical disk 2.
This is also used for control (track jump operation) when moving to a predetermined track (target track).

[Rotation Speed Control (Rotation Speed Control)] The optical disc apparatus 1 controls the rotation speed of the spindle motor 8 at 1 × speed such as 1 ×, 2 ×, 4 ×, 6 ×, 8 ×, and 12 × speed. Can be changed in multiple steps by an integer multiple of. This change is performed by a command from the computer 41.

For example, at the time of recording and reproduction, the rotation speed (rotation speed) of the spindle motor 8 is controlled in a state where the speed is set to a predetermined speed (in principle, the speed will be described as 1 ×).

The method of controlling the number of revolutions includes WOBBLE.
A method of controlling with a PWM (Puls Width Modulation) signal, that is, a spindle servo (WOBBLE servo) using a WOBBLE signal, a method of controlling with a FG PWM signal, that is, a spindle servo (FG servo) using an FG signal, and an EFM PWM There is a method of controlling with a signal, that is, a spindle servo (EFM servo) using an EFM signal. Hereinafter, these will be sequentially described.

The WOBBLE PWM signal is WOBBL
This is a spindle motor control signal generated by the E servo controller 22. Specifically, it is a digital signal (continuous pulse) of 0-5V level.

This WOBBLE PWM signal corresponds to WOB
The signal is input from the BLE servo controller 22 to the PWM signal smoothing filter 12, smoothed by the PWM signal smoothing filter 12, that is, converted into a control voltage (control signal), and input to the driver 11. And driver 1
1 drives the spindle motor 8 to rotate based on the control voltage.

In this case, the WOBBLE servo controller 22 sets the pulse width (duty ratio) of the WOBBLE PWM signal so that the frequency (period) of the WOBBLE signal becomes a target value (for example, 22.05 kHz at 1 × speed). Adjust). Thus, the spindle servo is operated so that the rotation speed (rotation speed) of the spindle motor 8 becomes the target rotation speed (first target rotation speed, second target rotation speed).

The FG PWM signal is a spindle motor control signal generated by the control means 13. In particular,
It is a digital signal (continuous pulse) of 0-5V level.

This FG PWM signal is input from the control means 13 to the PWM signal smoothing filter 12, and the PWM
The signal is smoothed by an M signal smoothing filter 12, that is, converted into a control voltage (control signal) and input to the driver 11. Then, the driver 11 drives the spindle motor 8 to rotate based on the control voltage.

On the other hand, from the Hall element 9, the FG (Frequenc) corresponding to the rotation speed (rotation speed) of the spindle motor 8 is obtained.
y Generator) signal is output. This FG signal is
The signal is binarized by the G signal binarization circuit 23 to be a square wave, and is input to the frequency measurement unit (period measurement unit) 132 of the control unit 13.

In the frequency measuring section 132 of the control means 13,
The frequency (period) of the FG signal is measured based on the clock signal from the clock 32. And control means 13
Adjusts the pulse width (duty ratio) of the FG PWM signal so that the frequency (cycle) of the FG signal becomes a target value. Thus, the spindle servo is operated so that the rotation speed (rotation speed) of the spindle motor 8 becomes the target rotation speed.

The frequency of the FG signal is
Is proportional to the number of revolutions. Therefore, for example, in the case of 6 × speed, 1
The frequency of the FG signal is six times that of the double speed.

The EFM PWM signal is a spindle motor control signal generated by the CD servo controller 21. Specifically, it is a digital signal (continuous pulse) of 0-5V level.

The EFM PWM signal is input from the CD servo controller 21 to the PWM signal smoothing filter 12, and is smoothed by the PWM signal smoothing filter 12.
That is, it is converted into a control voltage (control signal) and input to the driver 11. Then, the driver 11 drives the spindle motor 8 to rotate based on the control voltage.

In this case, the CD servo controller 21
Adjusts the pulse width (duty ratio) of the EFM PWM signal such that the period of a predetermined pulse of the EFM signal, that is, the pulse having a period of 3T to 11T, becomes a target value. Thus, the spindle servo is operated so that the rotation speed (rotation speed) of the spindle motor 8 becomes the target rotation speed.

In the above-described rotation speed control (spindle servo), the actual rotation speed of the spindle motor 8 is
In order to keep the linear velocity on the optical disc 2 constant, the inner circumference and the outer circumference of the optical disc 2 are different (the innermost circumference is 2.5 times the outermost circumference). Therefore, when the spindle motor 8 rotates, information on the current speed setting, that is, information on the radial position of the optical head 3 is considered together with the target rotational speed.

Information on the radial position of the optical head 3 is obtained from the absolute time on the optical disk. This absolute time is determined by the sync signal generation / ATIP decoder 27 or CD.
ATIP or SU output from the servo controller 21
It is obtained from the Q data of the B code and the like, input to the control means 13 and grasped.

Next, in the optical disk device 1, the spindle motor 8 of the rotation drive mechanism is stopped, that is, from the state where the optical disk 2 is stopped (stop state of the optical disk 2), the rotation speed of the optical disk 2 is changed to the first target rotation speed. The control operation of the control means 13 at the time of (restart) will be described.

FIG. 16 is a flowchart showing the control operation of the control means 13 when the rotation speed of the optical disk 2 is set to the first target rotation speed from the state where the optical disk 2 is stopped. Hereinafter, description will be made based on this flowchart.

When a restart command is received, this program (rotation speed control routine at the start of servo) is executed. In this case, the rotation speed of the optical disc 2 is
Is set to the rotation speed immediately before stopping.

First, initialization is performed (step S10).
1). In step S101, for example, the laser diode of the optical head 3 is driven (lighted). Also CD
Initialization of a predetermined address (an area where the first target rotation speed of the optical disc 2 is stored) of the servo controller 21, the WOBBLE servo controller 22, and the memory 26 is performed.

Next, a servo start operation start mode is set (step S102). Next, it is determined whether or not the currently set rotation speed of the optical disk 2, that is, the first target rotation speed is equal to or lower than N times speed (reference value) (step S103).

[0168] The above N indicates that the optical head 3 is located at the innermost periphery of the optical disk 2 and the rotation speed control (for example, FG servo) is performed so that the rotation speed of the optical disk 2 becomes N times faster. Various servo operations such as focus control, tracking control and thread control, and various automatic adjustments such as signal initialization (standardization) to be described later can be performed reliably (stable) in advance. I have.

If it is determined in step S103 that the first target rotation speed is equal to or lower than the N-times speed, the spindle motor 8 is started, and the rotation speed control is performed so that the rotation speed of the optical disk 2 becomes the first target rotation speed. (For example, FG servo). Then, the spindle servo is applied (turned on) so that the rotation speed of the optical disk 2 becomes the first target rotation speed.
By now, various servo operations (servo control) such as the above-described focus control (objective lens drive control), tracking control (objective lens drive control), and sled control (feed control of the optical head 3), and signal initialization (Automatic adjustment) such as (normalization) (step S10)
4).

In the initialization of the signal, for example, calibration (adjustment of signal amplitude) and adjustment of a reference level of a signal for canceling (reducing) offset are performed. Examples of the signal to be initialized include a focus error signal, a tracking error signal, a thread error signal, and an HF signal.

If it is determined in step S103 that the first target rotation speed exceeds the N-times speed, the first
Is stored in a predetermined address of the memory 26 (step S105).

Next, the spindle motor 8 is started,
The rotation speed of the optical disc 2 is equal to the second target rotation speed, ie, N
The rotation speed control (for example, FG servo) is started so that the speed becomes double (Step S106). By this rotation speed control, the rotation speed of the optical disk 2 once converges to the second target rotation speed, that is, N times speed.

Next, various servo operations such as the focus control, tracking control, and sled control described above,
Various automatic adjustments such as the aforementioned signal initialization are started (step S107). These various servo operations and various automatic adjustments are performed until the rotation speed of the optical disk 2 converges to N times speed.

In this case, since the second target rotation speed is lower than the first target rotation speed, various servo operations and various automatic adjustments can be performed stably.

FIG. 17 is a graph showing the change over time of the rotation speed of the optical disk 2 when the rotation speed of the optical disk 2 is set to the first target rotation speed from the state where the optical disk 2 is stopped. This graph shows that the first target rotation speed is 6 times speed,
This is a case where the second target rotation speed is set to double speed (N = 2).

As shown in the figure, when the rotation speed of the optical disk 2 is increased to 6 times speed from the state where the optical disk 2 is stopped, the rotation speed of the optical disk 2 is once converged to 2 times speed.
After that, it accelerates to 6 times speed.

In this case, when the time when the spindle motor 8 is started is t ₀ , the spindle servo is operated so that the rotation speed of the optical disk 2 converges to double speed, that is, the rotation speed of the optical disk 2 becomes double speed. The time when (ON) is t ₁ , and the time when the spindle servo is operated so that the rotation speed of the optical disc 2 becomes 6 times speed is t ₂ .

From t _{0 to} t ₁ , that is, from the start of the rotation of the optical disk 2 until the rotation speed of the optical disk 2 converges to double speed, focus control, tracking control and thread control are performed in this order. , Focus servo, tracking servo and thread servo. After the tracking servo is applied, the various automatic adjustments described above are performed.

[0179] It should be noted that, since the spindle servo is applied at t _1, all of the servo takes to t _1.

After step S107, it is determined whether or not all servos are turned on (turned on) (step S10).
8) If it is determined that all the servos have been activated, the first target rotational speed is read from a predetermined address in the memory 26 (step S109).

Next, the spindle motor 8 is accelerated so that the rotation speed of the optical disk 2 becomes the first target rotation speed. That is, rotation speed control (for example, FG servo) is started so that the rotation speed of the optical disc 2 becomes the first target rotation speed (step S110).

As shown in FIG. 17, the average acceleration of the rotation speed of the optical disk 2 between t ₁ and t ₂ is larger than the average acceleration between t ₀ and t ₁ .

After step S110, it is determined whether or not the rotation speed of the optical disk 2 has reached the first target rotation speed, that is, whether or not the spindle servo has been applied (turned on) (step S111). When it is determined that the rotation speed has reached the first target rotation speed, that is, when it is determined that the spindle servo has been applied, or after step S104, this program is terminated.

In the present invention, the first target rotation speed is
The rotation speed may be set higher or lower than the rotation speed immediately before the optical disk 2 stops.

For example, when the optical disk device 1 is restarted, data reading and reading other than data (for example, reading of disk information) are performed. However, when reading other than data is performed, The first target rotation speed can be set lower than the rotation speed immediately before the optical disc 2 stops. Thereby, heat generation can be suppressed.

As described above, according to the optical disk device 1, the optical disk 2 is switched from the stopped state to the optical disk 2.
When the rotation speed of the optical disk 2 is set to the first target rotation speed, the rotation speed of the optical disk 2 is once converged to the second target rotation speed, and various servo operations such as focus control, tracking control, and sled control are performed during that time. Therefore, various servo operations can be reliably performed.

In particular, even in the case of the optical disk 2 which is eccentric (the center of gravity is poorly balanced), the focus servo, the tracking servo and the thread servo can be more reliably applied.

Although the amplitude of the signal fluctuates according to the rotation speed of the optical disk 2, a conventional optical disk configured to accelerate the rotation speed of the optical disk 2 from the stop state of the optical disk 2 to a first target rotation speed is used. In this case, since the calibration is performed when the optical disk 2 rotates at a high speed and the acceleration of the rotation speed is relatively high, the amplitude of the signal may not be adjusted to an appropriate value. However, in the optical disk device 1, the calibration is performed when the optical disk 2 rotates at a low speed and the acceleration of the number of rotations is relatively low, so that the signal amplitude can be more reliably adjusted to an appropriate value.

In the conventional optical disk device, the reference level of the signal is adjusted when the optical disk 2 rotates at a high speed and the acceleration of the rotation speed is relatively high.
Although there is a possibility that the adjustment cannot be performed sufficiently, in the optical disc apparatus 1, the reference level of the signal is adjusted when the optical disc 2 rotates at a low speed and the acceleration of the rotational speed is relatively low, so that the optical disc apparatus 1 can be more reliably performed. That adjustment can be made.

The optical disk device of the present invention is similar to the above-described CD.
-R drive device, other than this, for example, CD-R
Various optical disk devices for recording and reproducing optical disks having a pre-groove such as W, DVD-R, DVD-RAM,
The present invention can be applied to various optical disk devices for reproducing optical disks such as CDs (compact disks) and CD-ROMs.

The optical disk device of the present invention has been described based on the illustrated embodiment. However, the present invention is not limited to this, and each component may have any configuration having the same function. Can be replaced by

For example, in the present invention, the above-described control of the rotation speed when the rotation speed of the optical disk is set to the first target rotation speed is not limited to the restarting from the standby state, but also when the optical disk is mounted. May be configured to be performed at that time.

[0193]

As described above, according to the optical disk apparatus of the present invention, when the rotation speed of the optical disk is set to the first target rotation speed, the rotation speed of the optical disk is temporarily lower than the first target rotation speed. Converge to a second target speed, during which
Since drive control (for example, focus control and tracking control) of the objective lens is performed, drive control of the objective lens can be reliably performed.

In particular, even in the case of an eccentric optical disk (poor balance in the center of gravity), the focus servo and the tracking servo can be more reliably applied.

When the signal initialization (for example, the adjustment of the signal amplitude and the adjustment of the reference level of the signal) is performed before the rotation speed of the optical disk converges to the second target rotation speed, it is ensured. Signal initialization can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a state where an optical disk device of the present invention is connected to a computer.

FIG. 2 is a block diagram showing an embodiment of the optical disk device of the present invention.

FIG. 3 is a timing chart showing an ENCODE EFM signal from an EFM / CDROM encoder control unit and an ENCODE EFM signal from a laser control unit according to the present invention.

FIG. 4 shows an ATIP-SYNC signal according to the present invention and SUBCODE from a sync signal generation / ATIP decoder;
6 is a timing chart showing a -SYNC signal and an ATIP ERROR signal.

FIG. 5 shows an ATIP-SYNC signal according to the present invention and a SUBCODE from a sync signal generation / ATIP decoder.
-SYNC signal and SU from CD servo controller
6 is a timing chart showing a BCODE-SYNC signal.

FIG. 6 shows 1T Biphase ATI according to the present invention.
P timing, WOBBLE signal, WO after binarization
6 is a timing chart showing a BLE signal.

FIG. 7 shows a BIDATA signal and BICL according to the present invention.
5 is a timing chart showing an OCK signal and an ATIP-SYNC signal.

FIG. 8 is a diagram showing a format of an ATIP frame according to the present invention.

FIG. 9 shows an ATIP-SYNC signal and S
6 is a timing chart showing a UBCODE-SYNC signal.

FIG. 10 shows an input signal to a peak / bottom detection circuit according to the present invention, the amplitude (envelope) of the input signal,
6 is a timing chart showing a PEEK signal and a BOTTOM signal.

FIG. 11 is a timing chart showing a SUBCODE-SYNC signal and a C1ERROR signal from a CD servo controller according to the present invention.

FIG. 12 is a timing chart showing a DATA signal, an LRCLOCK signal, and a BITCLOCK signal in an audio format according to the present invention.

FIG. 13 shows a SUBCODE-SYNC signal from a CD servo controller and FRAME SY in the present invention.
6 is a timing chart showing an NC signal and an HF signal (EFM signal).

FIG. 14 is a diagram showing a format of 96 bits of Q data according to the present invention.

FIG. 15 is a diagram showing one subcode frame in the present invention.

FIG. 16 is a flowchart showing a control operation of a control unit when the rotation speed of the optical disc is set to a first target rotation speed from a state where the optical disc is stopped in the present invention.

FIG. 17 is a graph showing a change with time of the rotation speed of the optical disk when the rotation speed of the optical disk is set to the first target rotation speed from a state where the optical disk is stopped.

[Explanation of symbols]

 Reference Signs List 1 optical disk device 10 casing 2 optical disk 3 optical head (optical pickup) 4 actuator 5 thread motor 6 driver 7 PWM signal smoothing filter 8 spindle motor 9 Hall element 11 driver 12 PWM signal smoothing filter 13 control means 131 counter 132 frequency measuring unit (period) Measurement unit) 14 Laser control unit 15 HF signal generation circuit 16 HF signal gain switching circuit 17 Peak / bottom detection circuit 18 Error signal generation circuit 19 WOBBLE signal detection circuit 21 CD servo controller 22 WOBBLE servo controller 23 FG signal binarization circuit 24 EFM / CDROM encoder controller 25, 26 memory 27 sync signal generation / ATIP decoder 28 CDROM decoder controller 29 memory 3 DESCRIPTION OF SYMBOLS 1 Interface control part 32-35 Clock 36 Address data bus 41 Computer 42 Keyboard 43 Mouse 44 Monitor 51, 52 Pulse S101-S111 Step

Claims (8)

[Claims] A rotation drive mechanism for mounting and rotating an optical disk; an optical head having an objective lens; signal processing means for processing a signal read from the optical disk by the optical head; An optical disc apparatus for controlling the driving of an optical head and a signal processing means, and for reproducing or recording / reproducing the optical disc, wherein when the rotation speed of the optical disc is set to a first target rotation speed,
Converging the rotation speed of the optical disk to a second target rotation speed lower than the first target rotation speed, and thereafter setting the rotation speed of the optical disk to the second target rotation speed; An optical disc apparatus characterized in that at least drive control of the objective lens is performed until the number is converged to a number. 2. A rotation drive mechanism for mounting and rotating an optical disk, an optical head having an objective lens, signal processing means for processing a signal read from the optical disk by the optical head, at least the rotation drive mechanism, An optical disk device for reproducing or recording / reproducing the optical disk, comprising: an optical head and control means for controlling the driving of a signal processing means, wherein the optical disk has a first target rotation speed from a stopped state of the optical disk. The number of revolutions of the optical disk converges to a second target number of revolutions lower than the first target number of revolutions, and then the first target number of revolutions, and the number of revolutions of the optical disc is set to the An optical disc is characterized in that at least drive control of the objective lens is performed before the objective lens converges to a second target rotational speed. Click device. 3. The optical disk according to claim 1, wherein when the first target rotation speed exceeds a reference value, the rotation speed of the optical disk is made to converge to the second target rotation speed. apparatus. 4. An average acceleration from the second target rotation speed to the first target rotation speed is higher than an average acceleration of the rotation speed of the optical disk up to the second target rotation speed. 4. The optical disk device according to claim 1, wherein the optical disk device is configured. 5. The optical disk device according to claim 1, wherein the drive control of the objective lens is at least one of focus control and tracking control. 6. The optical disc drive according to claim 1, further comprising: controlling the feed of the optical head until the rotation speed of the optical disk converges to the second target rotation speed.
An optical disc device according to any one of the above. 7. The optical disk device according to claim 1, wherein a signal is further initialized before the rotation speed of said optical disk converges to said second target rotation speed. . 8. The optical disk device according to claim 7, wherein the initialization of the signal is at least one of adjustment of the amplitude of the signal and adjustment of the reference level of the signal.