JPH10283645A - Optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical disk device capable of withstanding an extensive range of operating temps. SOLUTION: In an optical disk device performing the automatic adjustment of a tracking offset, the device is provided with a detection means detecting the temp. change of the vicinity of an optical pickup 4, a storage means storing the control data of the tracking offset and a means adjusting the tracking offset by updating the set value of the tracking offset while reading out the control data stored in the storage means when a temp. deviates off the preliminarily set temps. As a result, since the device can perform the automatic adjustment of the tracking offset without interrupting an operation temporarily even when a remarkable temp. change is generated during the reproducing or the recording operation of an optical disk, the reproducing or the recording of the optical disk are continued in the extensive range of ambient temps.

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 such as a CD player and an MD recorder which can control a tracking offset.

[0002]

2. Description of the Related Art A conventional technique will be described with reference to the drawings. FIG. 4 is a block diagram showing a configuration of a part for adjusting a tracking offset of a conventional optical disc device, and FIG. 5 is a flowchart showing a conventional tracking offset adjusting operation. FIG. 6A is a diagram illustrating a signal waveform before the tracking offset adjustment, and FIG. 6B is a diagram illustrating the tracking error signal after the adjustment.

Conventionally, an optical disk device has a spindle motor 2 for driving the optical disk 1 to rotate.
Optical pickup 4 for reading digital information recorded on
Having. The signal read by the optical pickup 4 is amplified by the head amplifier 5, and various servo signals such as focus servo, torsoking servo, slide servo, and spindle servo are processed by the servo processing IC 3, and the servo driver 3 performs control. ', The spindle motor 2 and the optical pickup 4 are operated to perform recording or reproduction on the optical disk 1.

[0004] A micro computer (hereinafter referred to as a microcomputer) 15 instructs a servo processing IC 3 such as an operation command for controlling each operation of the spindle motor 2 and the optical pickup 4. The servo processing IC 3 once releases the servo loop by the tracking offset adjustment command sent from the microcomputer 15 and detects the DC component of the tracking error signal generated by the temperature characteristic of the detector sensitivity of the optical pickup 4 and the detection result. Is sent to the microcomputer 15.

[0005] Based on the detection result sent from the servo processing IC 3, the microcomputer 15 generates a DC of the tracking error signal.
Servo processing of control data for canceling components
C3, the servo processing IC3 sets a servo value based on the sent control data, and sends it to the head amplifier 5. The tracking error signal having the DC component V2 before the adjustment is converted into the tracking error signal without the DC component after the adjustment, the adjustment of the tracking offset is completed, and the recording or reproducing operation is started.

The operation for adjusting the torso offset will be described with reference to a flowchart shown in FIG. In order to adjust the tracking offset at the start of recording or reproduction, the microcomputer 15 temporarily turns off the tracking servo.
FF is set (S11).

The DC component V2 of the amplitude V1 of the tracking error signal output from the head amplifier 5 is detected, and a bias voltage -V2 is applied to the servo processing IC 3 to obtain the DC component V2.
, And the tracking offset is adjusted to 0 by the head amplifier 5 as shown in the normal state in FIG. 6B (S12). Turn on tracking servo
Then, recording or reproduction is started (S1).
4).

While the recording or reproducing operation is continued,
The temperature inside the optical disk device rises, or in the case of a portable type, the offset voltage is warmed or cooled by a change in the temperature of the outside air or the like, so that the offset voltage is within the allowable operating range ± V3.
(Approximately 15% of V1), the tracking servo deviates, and the DC component V2 'shown in FIG. 6B is generated, and the tracking servo does not operate. When the reproduction becomes impossible due to the temperature change, the reproduction state may be turned off and the reproduction operation may be performed by performing the offset adjustment operation again.
It is difficult to form a product by performing a control loop of a tracking servo capable of maintaining a reproducing operation in a temperature range of, for example, -10 ° C. to 40 ° C. in a reproducing operation range with a fixed coefficient correction.

[0009]

However, in the above prior art, the adjustment of the tracking offset is performed by the reproducing operation,
Or turn off the servo loop at the start of the recording operation
Since the adjustment is performed only once, it is not readjusted during the reproducing operation or the recording operation thereafter. However, after the completion of the adjustment, a time elapses, the peripheral temperature in the vicinity of the optical pickup rises, and a state in which the tracking offset due to a large change in the temperature cannot be corrected occurs. There has been a problem that the offset becomes large and a signal cannot be recorded on the optical disk or the recorded signal cannot be reproduced in the middle.

[0010]

SUMMARY OF THE INVENTION The present invention relates to an optical disk apparatus for recording a signal on or reproducing a signal recorded on an optical disk, a temperature detecting means for detecting a temperature in the apparatus, and a tracking offset generated by a temperature difference. An optical disk comprising: storage means for storing control data to be read, and means for reading out the control data stored in the storage means for the temperature detected by the temperature detection means and updating the tracking offset setting to adjust the tracking offset. Device.

Further, the present invention relates to an optical disc apparatus for recording a signal on an optical disc or reproducing a recorded signal, a temperature detecting means for detecting a temperature near an optical pickup, and a data for controlling a tracking offset generated by a temperature difference. An optical disc device comprising: a storage unit for storing the control data stored in the storage unit of the temperature detected by the temperature detection unit, and a unit for reading out the control data and updating the setting of the tracking offset to adjust the tracking offset. .

Further, the present invention relates to an optical disk apparatus for recording a signal on an optical disk or reproducing a recorded signal, wherein a temperature detecting means for detecting a temperature change from a reproduced signal which changes in accordance with a temperature change in the vicinity of the optical pickup. A storage unit for storing data for controlling a tracking offset caused by a temperature difference; and reading control data stored in the storage unit for the temperature detected by the temperature detection unit and updating the setting of the tracking offset to update the tracking offset. Is an optical disc device provided with a means for adjusting the distance.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an optical disk drive according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a D (mini-disc) recorder.
The operation of reproducing and recording using a mini disc (MD) as an optical disc will be described. The MD 1 is housed in the cartridge 1A, and is mounted on the turntable 2B by loading the cartridge 1A into the MD recorder. In the cartridge 1A, the MD 1 is fixed at the center on the turntable 2B and the spindle motor 2
Is driven to rotate.

When the shutter provided on the cartridge 1A is opened, the optical pickup 4 and the magnetic head 16 are opened.
Is slid by the slide motor 18 in the axial direction of the MD1, and recording and reproduction of signals are performed on predetermined tracks of the MD1.

When a signal is recorded on the MD 1, a switching signal is recorded by the laser beam irradiation by the optical pickup 4 and a magnetic head driving circuit 17 so that the magnetic head 16 generates an NS pole magnetic field corresponding to the recording signal. You.

A recording input signal is inputted from the input terminal 14 or a digital audio tape recorder (DAT) or a compact disk (CD) player 21 and is converted into a digital signal by an analog-to-digital converter (ADC) 11.
The digital signal is time-axis-compressed by an ATRAC (Adaptive Transform Acoustic Coding) modulation / demodulation circuit 10 and is temporarily stored in a memory 9 as a buffer memory via an anti-vibration memory controller 8 for a predetermined period of time.
to Fourteen Modulation) / ACIRC (Adaptive Cros)
s Interleave Read-solomon Code) The modulation / demodulation circuit 7 modulates the recording signal into a recording signal conforming to the recording format, sends the recording signal to the magnetic head 16 via the magnetic head driving circuit 17, and the system controller (microcomputer) 15. Under the control, the reproduction or recording output is supplied to the optical pickup 4 via the head amplifier 5. Magnetic head 16, optical pickup 4, and spindle motor 2
Is controlled via a servo processing IC 3 and a servo driver 3 ′, and recording is performed on a predetermined track.

Next, the reproducing operation will be described. A signal recorded on a predetermined track of the MD 1 is converted into an electric signal by the optical pickup 4 and amplified by the head amplifier 5. The rotation control of the MD 1 and the tracking servo control of the optical pickup 4 are performed by a microcomputer 1
5 through the servo processing IC 3 and the servo driver 3 ′.

The reproduced signal amplified by the head amplifier 5 is demodulated by an EFM / ACIRC modulation / demodulation circuit 7 via an address recorder 6 and is temporarily stored in a memory 9 of a buffer memory via an anti-vibration memory controller 8.

The signal temporarily stored in the memory 9 is transmitted by the system controller 15 to the vibration-proof memory controller 8.
The signal is sent to an ATRAC modulation / demodulation circuit 10 via a demodulation circuit, demodulated into a signal whose time axis is expanded by the demodulation circuit, converted into an analog signal by a digital / analog converter (DAC) 12, and output from an output terminal 13.

The reproduction operation is performed by operating the M track from the operation unit 22.
(M songs), and then instructing to successively reproduce N tracks (N songs), the reproduction of the track N is started after the search time S is required after the reproduction of the track M. A regular time interval is provided so as to provide an inter-song portion where the M and N songs are not connected and reproduced, and normal reproduction is performed. The data recorded on the track has time information, and the time axis of the recorded signal is reconstructed at the time of reproduction to maintain the continuity of the information.

The contents of the operation of the microcomputer 15 are displayed on the display unit 19 provided on the panel unit of the MD recorder by operating a key switch or the like of the operation unit 22.

In the MD, time-axis-compressed data is recorded for each track. Normal track M followed by track N
Is designated from the operation unit 22 and when the signal is reproduced, the signal of each track on the MD1 disc is represented by track M.
Etc. are recorded.

A temperature sensor 3A is provided on the frame of the optical pickup 4. Data detected by the temperature sensor is input to the microcomputer 15 and the temperature is detected. Microcomputer 15
In the memory 15 ′, control data corresponding to the temperature characteristic of the tracking offset of the optical pickup 4 is previously stored in a predetermined temperature range. For example, data for canceling the DC component of the tracking error signal is read out by the microcomputer 15 in accordance with the contents stored in the memory shown in FIG. 3 in advance, processed by the servo processing IC 3, and the optical pickup is subjected to tracking servo by the head amplifier 5. You.

Next, according to the flowchart shown in FIG.
A switching operation for controlling the tracking offset of the optical pickup 4 in the MD recorder according to the present embodiment in accordance with the temperature in the apparatus will be described. When the MD recorder is in the recording or reproducing state, the microcomputer 15 detects the temperature from the temperature sensor 3A at a predetermined time interval (S1), takes the detected data into the microcomputer 15, and determines the temperature range and the temperature category. The current temperature is determined and stored in the memory 15 '(S
2).

The microcomputer 15 cancels the offset by, for example, as shown in FIG. 3, for each temperature range, the control data previously stored in the memory 15 'as the control data of the tracking offset adapted to the optical pickup 4 to be used. Then, the control data at the current temperature is read out (S3), input to the servo processing IC 3 to set data for canceling the offset, and update the tracking offset control via the head amplifier 5 (S4).

During the recording or reproducing operation of the MD recorder (S
5) Every time the temperature detected by the temperature sensor 3A changes beyond a predetermined range or every time a predetermined period elapses, the process returns to S1 to repeat the tracking offset update control (S
6). If the process is terminated without any change in the temperature, the process is terminated as it is. If the recording or reproduction is continued, the process returns to S5 to monitor whether or not the detected temperature in S6 has changed.

In the MD recorder, recording and reproduction are performed by time-axis-compressed data.
Detects the temperature even during recording or reproduction, or during recording / reproduction, and detects a temperature change when the temperature exceeds a predetermined temperature range stored in the memory 15 ′, and detects the temperature change from the memory 15 ′. The tracking offset data is read out, and the tracking offset data is constantly updated without breaking the tracking servo loop, so that the offset of the control loop can follow the temperature change.

Further, in another embodiment, a temperature sensor 3A for measuring the temperature around and near the optical pickup 4 is provided in an optical disk device having an automatic tracking adjustment function, and a memory 15 'in which a power supply is backed up is provided. A storage means is provided which does not erase stored data even when the power is turned off.

In the memory 15 ', control data of the temperature and the tracking offset of the optical pickup 4 are previously stored at the time of shipment from the factory as shown in FIG. The temperature is compared with the temperature stored in the memory 15 'by the temperature sensor 3A, and when a temperature change is detected or at a certain time interval, the microcomputer 15 stores the control data in the memory 1'.
Automatically adjusts the tracking offset value read from 5 '.

According to the above-described embodiment, when the temperature around the optical pickup 3 changes to a temperature equal to or higher than the temperature of each temperature section recorded in the memory 15 'in advance, the tracking offset automatic adjustment set value is changed. Therefore, it is not necessary to cut a control loop to measure a DC component, and it is possible to immediately read out control data corresponding to temperature, correct a tracking offset, and execute a track servo. Thus, the reproduction / recording of the optical disk can be continued without the need.

As shown in FIG. 7, the control data in the predetermined temperature range is based on the mechanism of the supporting portion of the optical pickup as shown in FIG. And the temperature characteristic of an electrical component such as a semiconductor used for the photodetector are combined to produce a change in the offset value. Therefore, the microcomputer 15
It is also possible to increase or decrease the control loop gain together with the offset control, add a DC to correct the tracking offset, expand the usable temperature range of the device, and expand the temperature change characteristics A to N of each product over a wide range. It is possible to improve the accuracy of the offset control unique to each optical pickup by examining the characteristics of each variation in advance and storing the characteristics.

According to the present invention, even if there is a temperature change during the reproduction and recording of the optical disk, the reproduction and recording of the optical disk can be performed without interrupting the reproduction and recording of the optical disk.

In the embodiment, the automatic adjustment of the tracking offset has been described by controlling the head amplifier 5.
Can be similarly performed for an optical disk device that performs automatic adjustment of the tracking offset only by the internal calculation processing of the servo processing IC 3 without controlling the operation.

[0034]

According to the optical disk apparatus of the present invention, even if the temperature changes during the reproducing or recording operation of the optical disk,
Since the tracking offset is automatically adjusted without interrupting the reproduction or recording operation of the optical disk, it is possible to obtain an apparatus that operates continuously over a wide temperature range.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of an optical disk device of the present invention.

FIG. 2 is a flowchart showing the operation of the optical disk device of the present invention.

FIG. 3 is a diagram showing an embodiment of memory storage contents stored in a microcomputer of the present invention.

FIG. 4 is a block diagram showing a tracking servo circuit section of a conventional optical disc device.

FIG. 5 is a flowchart of a conventional optical disk device.

FIG. 6 is a diagram showing a DC offset of a conventional tracking error signal.

FIG. 7 shows D of a tracking error signal of the optical pickup.
The figure which shows the example of the variation with respect to the temperature change of C offset voltage.

[Explanation of symbols]

 Reference Signs List 1 MD 1A Cartridge 2 Spindle motor 2B Turntable 3 Servo processing IC 3 'Servo driver 4 Optical pickup 5 Head amplifier 6 Address recorder 7 EFM / ACIRC modulation / demodulation circuit 8 Vibration resistant memory controller 9 Memory 10 ATRAC modulation / demodulation circuit 11 ADC Reference Signs List 12 DAC 13 Output terminal 14 Input terminal 15 System controller 15 'Memory 16 Magnetic head 17 Magnetic head drive circuit 18 Slide motor 19 Display unit 20 DAT 21 CD player 22 Operation unit

Claims (3)

[Claims] 1. An optical disk device for recording a signal on an optical disk or reproducing a signal recorded on the optical disk, a temperature detection unit for detecting a temperature in the device, and a storage unit for storing control data for controlling a tracking offset caused by a temperature difference. An optical disk apparatus comprising: a control unit that reads control data stored in the storage unit at a temperature detected by the temperature detection unit and updates a tracking offset setting to adjust the tracking offset. 2. An optical disk device for recording a signal on an optical disk or reproducing a signal recorded on the optical disk, a temperature detecting means for detecting a temperature in the vicinity of the optical pickup, and a storage for storing data for controlling a tracking offset caused by a temperature difference. An optical disk device comprising: a control unit that reads control data stored in the storage unit of the temperature detected by the temperature detection unit and updates a tracking offset setting to adjust the tracking offset. 3. An optical disc apparatus for recording a signal on an optical disc or reproducing a signal recorded on the optical disc, comprising: a temperature detecting means for detecting a temperature change from a reproduction signal changing in response to a temperature change in the vicinity of the optical pickup; Storage means for storing data for controlling the generated tracking offset; and means for reading the control data stored in the storage means for the temperature detected by the temperature detection means and updating the tracking offset setting to adjust the tracking offset. An optical disk device comprising: