JP2001236651A - Optical disk device and position detecting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the exact addition of postscript when the write-in of data is interrupted, by exactly detecting the final writing position of the data and hastening the start of the write-in of the data. SOLUTION: By a data transfer means 3, the data to be recorded are transferred to a light emitting means 2 while controlling the positional information on the data, and the data are recorded by the light emitting means 2 in the manner of irradiating the optical disk 11 with laser beams. When the error is generated and the laser beam output of the light emitting means 2 is stopped, this state is detected by a means 4 for detecting the stop of output and notified to a data transfer means 3, then the positional information on the data being transferred at the notified time point is stored in a positional information storage means 5 by the data transfer means 3.

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 capable of recording data and a position detecting method,
The present invention relates to an optical disk device and a position detecting method for accurately detecting a final writing position when data writing is interrupted due to some error.

[0002]

2. Description of the Related Art In recent years, CDs (Compact Disks) and CD-ROMs (CD-Read Online) have been used as digital data storage media.
Optical disks such as y Memory) have become widespread, and among those optical disks that can only be played back in the past, those that can be recorded have been put to practical use. For example, in the CD system, there are a CD-R (CD-Recordable) that can be recorded only once, and a CD-RW (CD-Rewritable) that can be recorded a plurality of times.

The CD-R and CD-RW have a recording layer between a light transmitting layer and a reflecting layer, and meandering guides for guiding a light spot during recording and time management of recording signals. Except that a groove (pre-groove) is formed, the shape, dimensions, storage capacity, and the like are the same as those of a CD. In the data recording, in a CD-R, a recording layer of an organic dye irradiated with a laser beam is heated and melted to cause a chemical change.
This is performed by forming pits of the same type as the CD due to deformation and alteration. In the case of CD-RW, the recording layer is changed from crystal to amorphous by the heat of the laser beam, and the difference in reflectivity depends on the presence or absence of the pits. It is recorded in the same way.

A digital signal to be recorded is converted into an EFM (Eight to Fourteen Modulation) signal similar to that of a CD and output. The return light from the optical disk is converted into an electric signal by a light receiving element (photodiode), and each of the servos for focus and tracking is applied using the light signal. The spot of the laser light is always focused on the recording film surface and the track is formed. Controlled to trace.

From the return light from the optical disk, a wobble signal recorded by the meandering shape of the pre-groove is further detected, and the FM signal is centered on a predetermined frequency.
ATIP (Abosolute Time In Pregroove) indicating time information for each sector of the optical disk by modulating
Is obtained. When recording a CD-R or CD-RW, this ATIP is detected to detect time information of the current sector,
The recording start sector of the information is determined, and the rotation servo of the optical disk is applied. Then, in the information to be recorded, an EFM frame synchronization signal synchronized with the ATIP frame synchronization signal is recorded in a format similar to that of recording on a normal CD.

[0006]

However, in such an optical disk, when an error occurs during data recording, the recording is interrupted, and data subsequent to the recorded area is recorded (appended). By accurately specifying the last position information of the area where the data was written before the recording was interrupted, it is possible to perform accurate data recording without overlapping the recording information or conversely creating a gap in the writing area. it can.

[0007] The causes of the errors include abnormalities of a sled motor for moving the objective lens of the optical pickup from the inner circumference to the outer circumference of the optical disk, a spindle motor for rotating the optical disk, a failure of the laser light generating device, and the like.
A data write error or the like due to a synchronization shift during data modulation can be considered. Conventionally, when such an error occurs during data writing, the laser beam irradiation is stopped to stop recording, and after the error is cleared, the written data is reproduced to check the writing area again. And the last position was detected, and data was recorded from the position after this position.

However, in this method, since the data position is detected at a high speed, an error of several EFM frames often occurs in the detection of the final write position of the data, and the recorded data may not be reproduced correctly. Was. Further, since such a process of detecting the write end position is performed before the start of the additional writing, a certain time is required until the start of the writing, and the smooth additional writing operation is not performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. When data writing is interrupted, the final writing position of data is accurately detected, and the start of data writing is quick and accurate additional writing is possible. Optical disk device is provided.

It is another object of the present invention to provide a position detecting method capable of accurately detecting the final write position of data when data writing is interrupted.

[0011]

According to the present invention, in order to solve the above-mentioned problems, in an optical disk apparatus capable of recording data, data transfer means for managing and transmitting position information of data to be recorded, Light emitting means for irradiating the optical disc with laser light in response thereto, output stop detection means for detecting the output stop of the laser light and notifying the data transfer means, and output of the data when the stop of the laser light is notified. An optical disk device comprising: position information storage means for storing position information.

[0012] Such an optical disk device detects the stop of the output of the laser beam and stores the position information of the data being transferred at this time, so that the end position of the data writing can be accurately detected, and When the writing is restarted, the writing start position can be detected at high speed, and the data can be accurately added.

Further, in a position detecting method for detecting a final writing position when writing is interrupted by an error in a write-once optical disk device, a stop of output of a laser beam applied to an optical disk is detected, A position detection method characterized by storing position information of existing data.

In such a position detecting method, since the stop of the output of the laser beam is detected and the position information of the data transferred at this time is stored, it is possible to accurately detect the final position of the data writing, When writing is resumed,
This position information can be used for fast additional recording start and accurate additional recording of data.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a principle diagram of the optical disk device of the present invention.

In the optical disk device 1, the optical disk 1
1 is rotated by a spindle motor 12, and a laser beam output from the light emitting means 2 is irradiated on a signal recording surface of the optical disk 11, so that data is recorded on the optical disk 11. The data transfer means 3 transfers the data to the light emitting means 2 while managing the position information of the data to be recorded.

The output stop detecting means 4 is provided in the optical disk device 1.
When an error occurs in the data transmission means 3, the stop of the laser beam output from the light emitting means 2 is detected, and this is notified to the data transfer means 3. The data transfer means 3 counts the position information of the data at the EFM frame level together with the transfer of the data, and when the stop of the laser output is detected by the output stop detection means 4, the data transfer at this time is performed. The position information is detected and stored in the position information storage means 5.

The stop of the laser output is detected by a method of detecting the drive current or drive voltage of the light emitting means 2, a method of detecting the laser light output from the light emitting means 2, and a method of detecting the laser light emitted by the light emitting means 2 on the optical disk. For example, a method of detecting the light reflected by the light source 11 may be considered.

When the error of the optical disk device 1 is eliminated and the additional recording on the optical disk 11 is started, the light emitting means 2 is turned on by the light emitting means 2 based on the position information at the time of stopping the laser light output stored in the position information storing means 5. Optical disk 1 for irradiating
1 is directly designated, the irradiation spot of the laser light is moved to this position, the output of the laser light is restarted, and the data recording is started.

Next, FIG. 2 shows an example of the configuration of an optical disk device according to the present invention. The optical disk device 1 includes, for example, a CD-R,
It is suitable for use as a CD-RW data recording device. The optical disk device 1 includes a spindle motor 12 for rotating the optical disk 11, a light emitting element for irradiating the optical disk 11 with laser light, a light receiving element for receiving light reflected from the optical disk 11, and an objective lens for focusing and tracking. An OP block 13 provided with a driving actuator, a sled motor 14 for moving the OP block 13 in a radial direction of the optical disc 11,
A servo circuit 15 for driving and controlling the spindle motor 12, the actuator of the OP block 13, and the sled motor 14, a signal modulation circuit 16 for modulating data to be recorded on the optical disk 11, and a demodulation of data reflected and received on the optical disk 11 A signal processing circuit 17, an encoding / decoding circuit 18 for encoding data to be recorded and decoding data to be reproduced, a buffer memory 19 for temporarily storing recording data, an external host computer or the like, and recording and reproducing data, or An external interface circuit 20 for transmitting and receiving control signals; a CPU block 21 for controlling the entire optical disc device 1;
It consists of two.

When recording data, first, the data to be recorded is received by the external interface circuit 20 and stored in the buffer memory 19. Then, the spindle motor 12 is rotated by a command from the CPU block 21, and the optical disk 11 is irradiated with laser light at a reproduction output level. From the received signal, an ATIP signal, which is time information recorded in a pre-groove formed on the optical disk 11, is detected by a signal processing circuit 17, and based on the ATIP signal, a servo circuit 15 passes through a CPU block 21 and a spindle motor 12, a thread. The motor 14 is controlled to move the objective lens of the OP block 13 to a target recording position specified by the CPU block 21. At the same time, focusing and tracking servo are applied by the servo circuit 15 from the received light signal, and preparation is made so that data can be written to a target position.

When the data is converted by the encoding / decoding circuit 18 in accordance with a predetermined recording format and data transfer is prepared, the CPU block 21 passes the laser beam through the servo circuit 15 based on the ATIP signal from the signal processing circuit 17. The recording / output of the light emitting element is started, and at the same time, the transfer of data is started by the encoding / decoding circuit 18. The encoding / decoding circuit 18 inserts the EFM frame synchronization signal and the subcode frame synchronization signal into the recording data at a desired timing in synchronization with the ATIP and transfers the recording data. The transferred recording data is transmitted to the signal modulation circuit 16.
And the recording output of the light emitting element of the OP block 13 is controlled in accordance with the recording data.
Data is written to

During the data writing, errors such as an abnormality of the sled motor 14 and the spindle motor 12 and the like, a failure of the laser light generator, a data writing error due to a synchronization error at the time of data modulation, and the like occur. When the light output is stopped, the laser output is stopped.
The laser output control signal 13a detected in the block 13 and corresponding thereto is input to the signal processing circuit 17.
At this moment, the CPU block 21 extracts the position information of the EFM frame synchronization signal of the data counted together with the data transfer by the encode / decode circuit 18 and stores it in the memory 22. As described above, the time when the laser output to be written to the optical disk 11 is stopped is detected, and in synchronization with this detection, the accurate position information of the transferred recording data is detected. It is accurately specified in EFM frame units.

Next, when the error of the optical disk device 1 is recovered and the additional data is instructed from the CPU block 21, the subsequent data to be recorded in the buffer memory 19 is stored and prepared for transfer. Is rotated. Next, the CPU block 21 calls out the last recording position information of the data stored at the time of the recording interruption from the memory 22, designates this position to the servo circuit 15, controls the drive of the thread motor 14 and the actuator of the OP block 13, and The laser beam spot is moved to the final data recording position. At the same time when the spot moves to the target position, the encode / decode circuit 18 starts the data transfer accurately from the data position obtained from the final recording position information, and is EFM-modulated by the signal modulation circuit 16 so that the recording output of the laser light emitting element is changed. It starts and data is added following the last recording position.

As described above, since the final write position of data is accurately specified when data recording is interrupted, the position at which data is to be additionally written is accurately specified in EFM frame units, and this position is set as a target. Since additional writing is started by moving the light spot, the process of reproducing written data and detecting the end position of writing as in the conventional case is not required, and the laser light spot is moved to the writing start position at a high speed, and The data can be moved accurately, and accurate data can be added from this position.

Next, FIG. 3 shows an example of the configuration of the optical system of the OP block. An example of a method for detecting the stop of laser beam output will be described with reference to FIG. The standard optical system of the OP block is
A laser diode (LD) 31, a grating (diffraction grating) 32, a beam splitter (BSP) 33, a concave lens 34, a photodetector IC (PDIC) 35, a collimator lens 36, a mirror 37, a 1/4 wavelength plate 38, and an objective lens 39. Be composed.

When data is recorded on the optical disk 11, a laser beam is output according to the data recorded by the laser diode 31, and this output light is
Are reflected by the beam splitter 33, collimated by the collimator lens 36, reflected by the mirror 37, and
The light is polarized by the four-wavelength plate 38, collected by the objective lens 39 on the signal recording surface of the optical disk 11, and data is recorded. On the other hand, the reflected light reflected by the surface of the optical disk 11 is supplied to the objective lens 39 and the 波長 wavelength plate 38 similarly to the output light.
Passes through the mirror 37 and is reflected by the mirror 37 so that the collimator lens 36
Through the beam splitter 33 and the concave lens 34
Is received by the photodetector IC 35 via the. This light receiving signal is used for focusing and tracking servo, control of the thread motor 14 and the spindle motor 12, and the like.

When the recording of data on the optical disk 11 is interrupted by an error and the output of the laser diode 31 is stopped, the output stop of the laser beam is detected. The following three methods are considered. The first method is to connect an ammeter 30 to the driving circuit of the laser diode 31 as shown by connecting to the laser diode 31 in FIG.
1 or a voltmeter is connected, and the input current or input voltage for driving the laser diode 31 is measured.

In the second method, the laser diode 3
In the method of receiving the output light of No. 1 using a light receiving element, for example, a front monitor photodiode (FPD) 302 is installed on the extension of the optical path from the laser diode 31 to the grating 32 and the beam splitter 33 as shown in FIG. Then, the output light of the laser diode 31 transmitted through the beam splitter 33 is transmitted to the front monitor photodiode 30.
2, a method of receiving light can be considered.

Further, the third method is a method in which the laser light output from the laser diode 31 receives the reflected light reflected on the optical disk 11 by using a light receiving element. For example, the laser light is recorded on the optical disk 11. A method of detecting a signal using a photodetector IC 35 normally provided for detecting a signal is conceivable. This method has an advantage that it is not necessary to add a new component for detecting the stop of the laser beam output. In the third method, a signal which is actually applied to the optical disk is received.
This is considered to be a more reliable method than the second method. That is, for example, in the first method, the laser beam is output and in the optical path system from the grating 32 to the optical disk 11, the beam splitter 3 is used in the second method.
In the optical path system from the optical disk 3 to the optical disk 11, a failure occurs in the middle of the optical path.
If the data is not recorded because the laser beam is not irradiated on the optical disk 11, this may not be detected, and the final recording position of the optical disc 11 may not be detected.

Also in the case of the first, second and third methods, the maximum interval between the end of the pulse waveform output from the laser diode 31 and the next rising edge is determined by EFM modulation. Accordingly, when the output of the laser beam is not detected for a certain period of time or more, it can be determined that the output of the laser beam has been stopped due to some error or the like.

FIG. 4 is a timing chart showing the relationship between the EFM frame synchronization signal of the recording data and the detected laser output control signal. In FIG.
The EFM frame synchronization signal 42 when the frame position of the EFM 41 of the recording data managed by the encoding / decoding circuit 18 is, for example, n to n + 5, and the output waveform 43 of the laser light output from the laser diode 31 at this time. It is shown. The detection result of the laser output by any of the above-described methods is represented as a laser output control signal 13a, and the position information 44 of the data counted together with the transfer of the recording data at this time is represented by E.
It is shown in synchronization with the FM frame synchronization signal 42.

As shown in FIG. 4, the pulses of the laser output waveform 43 disappear during the output stop time 43a, and the output of the laser beam is stopped. At this time, the stop of the laser output is detected, and the laser output control signal 1
3a is directly input to the signal processing circuit 17, and the CPU block 21 stores the position information 44 of the recording data transferred by the encoding / decoding circuit 18 at this moment in the memory 22. That is, in the case of FIG. 4, since the laser output control signal 13a is OFF when the frame position of the EFM 41 is n + 2, the (n + 2) EFM frame is stored as the position information 44 of the last recording position of the data. become. As described above, by inputting the detection signal of the stop of the laser output directly to the signal processing circuit 17, it becomes possible to specify the final recording position at the EFM frame level in synchronization with the recording data to be transferred. I have.

[0034]

As described above, in the optical disk apparatus of the present invention, since the stop of the output of the laser beam is detected and the position information of the data being transferred at this time is stored, the data write end position can be accurately determined. It is possible to detect the write start position at a high speed at the time of resuming the data write, and perform the data additional write accurately.

Further, in the position detecting method of the present invention, since the stop of the output of the laser beam is detected and the position information of the data transferred at this time is stored, the final position of the data writing can be accurately detected. When data writing is resumed, this position information can be used for high-speed start of additional writing and accurate additional writing of data.

[Brief description of the drawings]

FIG. 1 shows a principle diagram of an optical disk device of the present invention.

FIG. 2 is a diagram showing a configuration example of an optical disk device of the present invention.

FIG. 3 is a diagram illustrating a configuration example of an optical system of an OP block.

FIG. 4 is a timing chart showing a relationship between an EFM frame synchronization signal of recording data and a detected laser output control signal.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical disk apparatus, 2 ... Light emission means, 3 ... Data transfer means, 4 ... Output stop detection means, 5 ... Position information storage means, 11 ... Optical disk, 12 ... Spindle motor

Claims (9)

[Claims] 1. An optical disk device capable of recording data, a data transfer unit that manages and transfers position information of data to be recorded, a light emitting unit that irradiates a laser beam to an optical disk according to the data, and a laser. Output stop detecting means for detecting the stop of light output and notifying the data transfer means, and position information storage means for storing position information of the data when the stop of the laser light is notified. Characteristic optical disk device. 2. The optical disk device according to claim 1, wherein said position information is obtained from an EFM frame synchronization signal. 3. The optical disk device according to claim 1, wherein the output stop detecting means detects the output stop of the laser light from a drive voltage of the light emitting means. 4. The optical disk device according to claim 1, wherein the output stop detecting means detects the output stop of the laser light from a drive current of the light emitting means. 5. The optical disk device according to claim 1, wherein the output stop detecting means detects the output stop of the laser light by receiving the output light from the light emitting means. 6. The output stop detecting means according to claim 1, wherein said output stop detecting means detects the output stop of said laser light by receiving reflected light of output light from said light emitting means reflected on said optical disk. Optical disk device. 7. The optical disk according to claim 1, wherein said optical disk is a write-once optical disk.
2. The optical disk device according to claim 1, wherein the optical disk device is an Once-type optical disk. 8. The optical disk according to claim 1, wherein said optical disk is a rewritable optical disk.
2. An optical disk device according to claim 1, wherein the optical disk device is an able) type optical disk. 9. A position detecting method for detecting a final writing position when writing is interrupted by an error in an optical disk device capable of recording data, wherein output stop of a laser beam applied to the optical disk is detected. A position detecting method, comprising storing position information of transferred recording data, and detecting the last writing from the position information.