JP2713681B2 - Optical disc information recording method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for recording information on an optical disk, and more particularly to a method and apparatus for recording information on an optical disk which can quickly recover when tracking is lost during information recording.

[0002]

2. Description of the Related Art Conventionally, in an information recording apparatus for an optical disk, a recording layer of the optical disk is altered or deformed by a laser beam, and information is recorded by changing a reflection direction or a reflectance of the laser beam during reproduction. .

[0003]

Therefore, if the tracking is lost for some reason during the recording of information, the recording of the information fails, and the optical disk on which the information was recorded at this time is rewritable. Other than that, the optical disk had become unusable.

That is, if tracking is lost for some reason such as disturbance (vibration or mechanical shock) or a defect while information is being recorded on the optical disk, control is lost on the recording surface of the optical disk. In this state, the information is recorded by irradiating a laser beam, and if the optical disk is of a non-rewritable type (write-once type), it cannot be used again. Further, even on a rewritable optical disk, information must be re-recorded from the beginning again, which is very troublesome.

On the other hand, a method of instantly turning off the laser beam when tracking is lost during recording of information has been realized, and a method of not recording information in a state out of control has also been realized. However, even with this method, the recording is interrupted on the way, so that the above problem cannot be solved in any case, resulting in a failure of the recording.

In view of the above problems, an object of the present invention is to provide an information recording method and an information recording apparatus for an optical disk capable of continuously recording information even when tracking is lost during recording of information. To provide.

[0007]

According to the first aspect of the present invention, there is provided an information recording method for an optical disc, wherein the optical disc is irradiated with a laser beam while tracking, and information is sequentially recorded on the optical disc. When the tracking is lost, the recording of the information is stopped, and the position where the tracking is lost is stored, and the information to be recorded after the position where the tracking is lost is stored, and from the vicinity of the position where the tracking is lost, The present invention proposes an information recording method for an optical disc in which tracking is performed again and the stored information to be recorded is sequentially recorded.

According to a second aspect of the present invention, in the information recording method for an optical disk according to the first aspect, when recording the stored information after the position where the tracking is lost, the recording speed is lower than the recording speed before the tracking was lost. We propose an information recording method for optical discs that records information at high speed.

According to a third aspect of the present invention, a rotating means for rotating the optical disk, a laser light irradiating means for irradiating the optical disk with laser light, and a tracking means for tracking an irradiation position of the laser light to an information recording position of the optical disk. And an information recording apparatus for an optical disc, comprising: a laser beam irradiation control unit that controls laser beam irradiation by the laser beam irradiation unit based on recording target information; and a tracking state detection unit that detects the tracking state. Based on a detection result of the tracking state detecting means, when tracking is deviated, position detecting means for detecting a position on the optical disk where the tracking deviated,
Based on the detection result of the tracking state detection means,
When tracking is lost, at least information storage means for storing recording target information after the position where tracking is lost, and when tracking is lost, tracking correction means for performing re-tracking from the detection position of the position detection means. In addition to the above, the laser light irradiation control means sets the intensity of the laser light irradiated by the laser light irradiation means to a predetermined value or less when tracking is deviated based on the detection result of the tracking state detection means. ,
When the re-tracking is started, the intensity of the laser light is set to a predetermined value or more, and an information recording apparatus for an optical disc which controls the irradiation of the laser light by the laser light irradiation means based on the information stored in the information storage means. Suggest.

According to a fourth aspect of the present invention, in the information recording apparatus for an optical disk according to the third aspect, at least when the information stored in the information storage means is recorded after the tracking is lost, the tracking is lost. Rotation control means for rotating the optical disc at a higher speed than before is provided, and the laser light irradiation control means controls laser light irradiation by the laser light irradiation means in accordance with the rotation speed of the optical disc by the rotation control means. An information recording device for an optical disk is proposed.

[0011]

According to the first aspect of the present invention, when tracking is lost, recording of information on the optical disk is stopped, the position where tracking is lost is stored, and information is recorded after the position where tracking is lost. Information is stored. Further, the tracking is performed again from the vicinity of the position where the tracking is lost, and the stored information is sequentially recorded.

Further, according to the second aspect, when recording the stored information after the position where the tracking is lost, the information is recorded at a higher speed than the recording speed before the tracking is lost. As a result, a time delay caused by the deviated tracking is reduced.

According to the third aspect, the tracking state is detected by the tracking state detecting means, and based on the detection result, when tracking is lost, the position on the optical disk on which tracking has been lost is detected by the position detecting means. The position is detected, and information to be recorded at least after the position at which tracking is lost is stored by the information storage unit, and the intensity of the laser beam irradiated by the laser beam irradiation unit cannot be recorded by the laser beam irradiation control unit. It is set to a predetermined value or less. Further, the tracking correction means performs re-tracking from the detection position of the position detection means, and after the re-tracking is started, the laser light irradiation control means sets the intensity of the laser light to a predetermined value at which information can be recorded. As mentioned above,
The irradiation of the laser beam by the laser beam irradiating unit is controlled based on the information stored in the information storing unit, and the recording of the information is restarted.

Further, according to the present invention, when recording the information stored in the information storage means at least after the tracking is released, the optical disc is rotated at a higher speed than before the tracking is released by the rotation control means. In addition, the laser light irradiation control means controls the laser light irradiation by the laser light irradiation means in accordance with the rotation speed of the optical disk. As a result, a time delay caused by the deviated tracking is reduced.

[0015]

FIG. 1 is a block diagram showing an information recording apparatus for an optical disc according to an embodiment of the present invention.
It hijacks the mpact Disc system standard. In the figure, 1 is an optical disk, 2 is an information recording device, which comprises a data input unit 21, a data conversion unit 22, and a recording unit 23.

The optical disc 1 is, for example, a write-once compact disc, and has a spiral groove (guide groove) 11 wobbled (oscillated) at a predetermined cycle as shown in FIG. The tracking can be performed using the groove 11. In addition, an ATIP code (absolute time information) is recorded in the groove itself, and by detecting the ATIP code, the optical pickup described later can be moved accurately (Japanese Patent Application Laid-Open Nos. 56-105343 and 56-105343). Showa 6
3-87682, JP-A-63-10345).

The data input section 21 includes an analog input interface 211, an analog / digital (hereinafter, referred to as A / D) converter 212, and a digital input interface 21.
3 and a changeover switch 214. When the information to be recorded is supplied as an analog signal, the analog signal is supplied to the A through the analog input interface 211.
The signal is input to a / D converter 212 and converted into a digital signal DA1. When the information to be recorded is supplied by a digital signal, the digital signal is input to the digital input interface 213 and input to the switch 214 as the digital signal DA2. The changeover switch 214 selects one of the digital signals DA1 and DA2 according to the supply state of the information to be recorded, and outputs it to the data converter 22.

The data conversion section 22 comprises a well-known EFM encoder 221 and a buffer memory 222.
The EFM encoder 221 converts the digital signal DA output from the data input unit 21 into an EFM (Eight to Fourteen M
odulation) and outputs the result to the buffer memory 222. The buffer memory 222 sequentially stores digital data output from the EFM encoder 221 and stores the digital data stored based on a control signal from a system controller 231 of the recording unit 23 described later.
Output to 3.

The recording unit 23 includes a system controller 231
, A spindle motor 232, an optical pickup 233, a signal processing circuit 234, a synchronization circuit 235, a recording correction circuit 236, and a tracking control circuit 237. The spindle motor 232 rotates the optical disc 1 at a rotation speed based on a control signal from the system controller 231.
The optical pickup 233 includes a laser diode, a lens, a mirror, a photodetector, and the like, as is well known, and emits a laser beam based on a recording signal output from the recording correction circuit 236 and receives reflected light from the optical disk 1. Then, the light receiving signal PS corresponding to this is output.
The optical pickup 233 is a tracking control circuit 237.
From the optical disk 1 based on the control signal from the
It is configured to be movable so that the irradiation position of the laser beam can be tracked corresponding to 1.

The signal processing circuit 234 includes an optical pickup 233
The received light signal PS output from the
The focus control of the optical pickup 233 is performed based on S, the wobbling cycle of the groove 11 (hereinafter, referred to as a wobble signal) is detected from the received light signal PS, and a clock signal CK synchronized with the wobble signal is generated to generate a system controller 231. And output to the synchronization circuit 235. That is, when the rotation speed of the optical disc 1 changes and the cycle of the wobble signal changes, the cycle of the clock signal CK generated corresponding thereto also changes. Further, the signal processing circuit 234
Detects the ATIP code from the received light signal PS,
Absolute time based on P code
Output to

The synchronizing circuit 235 receives EFM-modulated digital data from the buffer memory 222, and receives a control signal from the system controller 231 and a signal processing circuit 234.
And outputs the input digital data at a predetermined timing synchronized with the clock signal CK.

The recording correction circuit 236 receives the digital data output from the synchronizing circuit 235, and responds to the digital data and, based on a control signal from the system controller 231, adjusts the voltage and the duty of the pulse width to optimal values. Optical pickup by generating a recording signal set to
Output to 233.

The tracking control circuit 237 moves the position of the optical pickup 233 based on a control signal from the system controller 231 and also controls the position of the optical pickup 233.
The irradiation position of the laser beam is tracked corresponding to the groove 11 of the optical disc 1 based on the light receiving signal PS from the optical disc 1. Further, when tracking is lost, a tracking error signal ER is output and this is immediately notified to the system controller 231.

According to the present embodiment having the above-described configuration, when information to be recorded is input to the data input section 21, data for a predetermined time is stored in the buffer memory 222 before information is recorded on the optical disk 1. Stored. The system controller 231 drives the spindle motor 232 to rotate the optical disc 1 at a predetermined rotation speed, and after detecting that a predetermined amount of data has been stored in the buffer memory 222, the data stored in the buffer memory 222. Buffer memory 22 sequentially
Output from 2. In addition, the system controller 231
Starts tracking from the information recording start position via the tracking control circuit 237.

Thus, the data output from the buffer memory 222 is synchronized with the clock signal CK by the synchronization circuit 235, is output at a predetermined timing, and is converted into a recording signal by the recording correction circuit 236. A pulsed laser beam is emitted from the optical pickup 233 based on the recording signal, and information is recorded on the optical disk.

On the other hand, if tracking is lost for some reason such as disturbance (vibration or mechanical shock) or a defect while information is being recorded on the optical disk 1, the tracking control circuit 237 sends a signal to the system controller 231.
Outputs a tracking error signal ER. System controller 23 that inputs tracking error signal ER
1 is to stop the output of the recording signal from the recording correction circuit 236, stop the recording of information on the optical disk 1, and detect the position where tracking is deviated based on the absolute time information input from the signal processing circuit 234. Remember. Further, the output of data from the buffer memory 222 is stopped.

Thereafter, the system controller 231 sends a signal to the vicinity of the position where the tracking is lost (±
Then, the tracking is restarted, and the output stop state of the recording signal in the recording correction circuit 236 is released. Further, the system controller 231 outputs the stored data from the buffer memory 222 at a higher speed than before the tracking is lost, and increases the rotation speed of the spindle motor 232 correspondingly. As a result, information is recorded at a higher speed than before tracking is lost.

When the rotation speed of the optical disk 1 increases, the period of the clock signal CK generated by the signal processing circuit 234 changes correspondingly.
The cycle of the recording signal output from is changed according to the rotation of the optical disk 1 (the rotation of the spindle motor 232). At this time, under the control of the system controller 231, the time adjustment of the data output with respect to the data input is performed in the buffer memory 222. Further, the optimum value of the laser output changes with the change of the rotation speed, the linear speed, etc., but under the control of the system controller 231, the recording correction circuit 236 adjusts the laser output to the optimum value which matches the rotation speed and the linear speed of the optical disk 1. The values of the voltage of the recording signal and the duty of the pulse width are changed so as to obtain the values. As a result, information recorded after the position at which tracking is lost is almost normally recorded, and a time delay caused by tracking loss is reduced. Therefore, even if the tracking is lost during the recording of the information, the information can be continuously recorded, and unlike the conventional case, the information recording does not fail due to the lost tracking, and the optical disc can be read again. Never become unusable.

Further, the system controller 231 performs the above-described high-speed recording, and when the amount of data stored in the buffer memory 222 falls below a predetermined value, the rotation speed of the spindle motor 232, the voltage and pulse width of the recording signal. And the data output speed from the buffer memory are reset to normal values, and information is recorded at the normal speed.

The allowable time from when tracking is lost to when the tracking is restored is determined by the capacity of the memory mounted as the buffer memory 222. For example, in the case of the compact disk described above, the data input to the data input unit 21 is used. Since the input speed of the data is 1.4 Mbit / s, 1 Mbi
When a DRAM of t is used, there is a temporal buffer capacity of about 0.7 s (2.8 s for a 4 Mbit DRAM).

That is, even if tracking is lost during recording for some reason, the optical pickup 233 accesses at high speed, returns to the position where tracking is lost, performs high-speed recording, and inputs the data to the data input unit 21 in real time. The operation of narrowing the time difference from incoming data is 0.7s
If it can be completed within this time, the error in the part where tracking has been lost will be somewhat large, but it can be sufficiently compensated for by error correction processing during reproduction. Further, when tracking is deviated due to a general defect or slight vibration, about 0.7 s or more is an effective time for recovery.

By the way, in order to control the waveform of a recording signal to obtain a better recording state, it is common to perform correction at the time of recording. It is desirable to provide between the pickup 233 and the synchronization circuit 235. At this time, the recording correction circuit 236
And the synchronization circuit 235 may be mixed. As a result, the circuit system is simplified, and the cost can be reduced.

As shown in FIG. 3, a buffer memory 222 is provided in front of the EFM encoder 221 and a clock signal generated by the signal processing circuit 234 (optical disk 1) is controlled by using a clock generation circuit of the EFM encoder 221 as an external control.
May be input as a synchronizing signal.

That is, in the configuration of FIG. 3, the digital data DA output from the data input section 21 is input to the buffer memory 222, and the data output from the buffer memory 222 is transmitted to the recording correction circuit 236 via the EFM encoder 221. Is input to Further, a synchronization circuit 238 is provided in place of the synchronization circuit 235, and the synchronization signal generated from the clock signal CK in the synchronization circuit 238 is input to the EFM encoder 221.

In this case, data that is not EFM-modulated by the EFM encoder 221 and to which an error correction code such as CIRC is not added is stored in the buffer memory 222.
When a 1 Mbit DRAM is used, a temporal buffer capacity of about 1.4 s can be obtained.

Further, as shown in FIG. 4, an automatic gain control (AGC) circuit 239 for tracking control is used.
The tracking stability can be further increased by re-adjusting either the tracking gain or the offset or both at the time of re-tracking after the tracking is lost during the recording of information.

In this embodiment, the optical information recording medium is a write-once compact disc. However, the present invention is not limited to this.

In this embodiment, data is stored in the buffer memory 222 from the start of recording information. However, the present invention is not limited to this. Even if the data to be stored is stored in the buffer memory 222, substantially the same effect can be obtained.

[0039]

As described above, according to the first aspect of the present invention, when tracking is deviated, recording of information on the optical disk is temporarily stopped, and tracking is performed again from the vicinity of the deviated position. Thus, the stored information is sequentially recorded, so that the information can be continuously recorded, and the information recording does not fail due to the loss of tracking, and the optical disk cannot be reused. Disappears.

According to the second aspect of the present invention, in addition to the above effects, when recording the stored information after the position at which the tracking is lost, the information is recorded at a higher speed than the recording speed before the tracking was lost. Is recorded, so that a time delay caused by the interruption of the tracking can be reduced.

According to the third aspect, when tracking is lost, the recording of information on the optical disk is temporarily stopped by the laser beam irradiation control means, and the tracking correction means restarts from the vicinity of the position where the tracking is lost. Since tracking is performed and the stored information is sequentially recorded, information can be recorded continuously, and information recording does not fail due to missing tracking, and the optical disk can be reused. It will not be impossible.

According to a fourth aspect of the present invention, in addition to the above-described effects, when recording the stored information after the position where the tracking is lost, the information is recorded at a higher speed than the recording speed before the tracking was lost. Is recorded, the time delay caused by the interruption of the tracking can be mitigated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an information recording apparatus for an optical disc in one embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of an optical disc in one embodiment of the present invention.

FIG. 3 is a configuration diagram showing an information recording apparatus for an optical disc in another embodiment of the present invention.

FIG. 4 is a configuration diagram showing an information recording apparatus for an optical disc in another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical disk, 11 ... Groove, 2 ... Optical information recording device, 21 ... Data input part, 211 ... Analog input interface, 212 ... A / D converter, 223 ... Digital input interface, 214 ... Changeover switch, 22 ... Data conversion Unit, 221, EFM encoder, 222, buffer memory, 23, recording unit, 231, system controller, 232
… Spindle motor, 233… optical pickup, 234… signal processing circuit, 235, 238… synchronization circuit, 236… recording correction circuit, 237… tracking control circuit, 239… AGC circuit

Continuation of the front page (56) References JP-A-64-10431 (JP, A) JP-A-3-66031 (JP, A) JP-A-62-102432 (JP, A) JP-A-59-65946 (JP) JP-A-62-192938 (JP, A) JP-A-63-103435 (JP, A)

Claims (4)

(57) [Claims] 1. An information recording method for an optical disk, wherein a laser beam is irradiated on an optical disk while tracking, and information is sequentially recorded on the optical disk. The tracking state is monitored, and when the tracking is lost, the recording of the information is stopped. Then, while storing the position at which the tracking is lost, storing the recording target information after the position at which the tracking is lost, performing tracking again from near the position at which the tracking is lost, and recording the stored recording target information. Restarting the operation of the optical disk. 2. The optical disc according to claim 1, wherein, when recording the stored information after the position where the tracking is lost, the information is recorded at a higher speed than a recording speed before the tracking is lost. Information recording method. 3. Rotating means for rotating an optical disk, laser light irradiating means for irradiating the optical disk with laser light,
An optical disc comprising: a tracking unit that tracks an irradiation position of the laser light to an information recording position of the optical disc; and a laser light irradiation control unit that controls irradiation of the laser light by the laser light irradiation unit based on recording target information. In the information recording apparatus, tracking state detecting means for detecting the tracking state, and detecting the position on the optical disk where the tracking is lost when tracking is lost based on the detection result of the tracking state detecting means Position detecting means, based on the detection result of the tracking state detecting means,
When tracking is lost, information storage means for storing at least the information to be recorded after the position where tracking is lost, and tracking correction means for performing re-tracking from the detection position of the position detection means when tracking is lost. Along with the provision, the laser light irradiation control means, based on the detection result of the tracking state detection means, when tracking is deviated, the intensity of the laser light irradiated by the laser light irradiation means to a predetermined value or less When the re-tracking is started, the intensity of the laser light is set to a predetermined value or more, and irradiation of the laser light by the laser light irradiation unit is controlled based on information stored in the information storage unit. Characteristic information recording device for optical discs. 4. When recording information stored in the information storage means at least after tracking is lost, a rotation control means for rotating the optical disk at a higher speed than before the tracking is lost is provided, and the laser is provided. 4. The optical disk information recording apparatus according to claim 3, wherein the light irradiation control means controls the irradiation of the laser light by the laser light irradiation means in accordance with the rotation speed of the optical disk by the rotation control means.