JP2000057710A - Error correction method and optical disk device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an error correction method that can contribute to improvement in reliability of reproduced data. A data block including a group of data arranged along a predetermined number of rows and columns, and a first block for correcting an error included in data in a row direction of the data block.
And a data block with an error correction code having a second error correction code for correcting an error contained in the data in the column direction of the data block (ST14). The error included in the data block is corrected using the first error correction code included therein (ST20), and the error included in the data block is corrected using the second error correction code included in the data block with the error correction code (ST34).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an error correction code recorded on an optical disc.
The present invention relates to an error correction method for reproducing data including a character string, and correcting an error included in the reproduced data with an error correction code included in the reproduced data.

[0002] The present invention also relates to an optical disk apparatus for reproducing data including an error correction code recorded on an optical disk and correcting an error included in the reproduced data by using an error correction code included in the reproduced data. .

[0003]

2. Description of the Related Art In recent years, various types of optical disks have been proposed. Among them are DVs characterized by high density recording.
D (Digital Video Disk) -RAM is included. The DVD-RAM is formed with a track for recording data, and the track is formed with a plurality of sector fields for recording a predetermined unit of data.

A DVD-RAM includes an ECC (Erro
r Correction Code) Data in a format called a block is recorded. Strictly speaking, the data of the ECC block is divided into 16, and each is recorded in one sector field.

The ECC block is composed of a data block (a group of user data), a horizontal error correction code, and a vertical error correction code. The data block is composed of data arranged along a predetermined number of rows and columns. The horizontal error correction code is
It corrects an error included in the data in the column direction of the data block. The vertical error correction code corrects an error included in data in the row direction of the data block.

As described above, by providing the ECC block with the horizontal and vertical error correction codes, it is possible to perform more powerful error correction as compared with the error correction from one direction. Further, the horizontal and vertical error correction codes have a limited error correction capability. That is, when the number of errors included in the data in the column direction or the data in the row direction in the data block exceeds a predetermined number, error correction cannot be performed.

Here, the procedure of the error correction processing will be briefly described. First, a horizontal error correction process is performed for each data in the column direction of the data block by the horizontal error correction code. When the error included in the data block is completely corrected by the horizontal error correction processing, the error correction processing is completed. During the horizontal error correction process, if the number of errors included in the data in a certain column direction exceeds a predetermined number and the error cannot be corrected, a flag indicating that the error correction has not been processed for this column. Is set up. Subsequently, a vertical error correction process is performed for each row data in the data block by the vertical error correction code. During the vertical error correction process, if the number of errors contained in data in a certain row direction exceeds a predetermined number and error correction cannot be performed, a flag indicating that error correction has not been performed for this row. Is set up. in this way,
Repeat the horizontal and vertical error correction processing alternately,
Errors contained in the data block are corrected.

[0008]

The above-described conventional error correction processing is based on the premise that 16 sector fields in which data constituting one ECC block is recorded are normally reproduced. In other words, if 16 sector fields in which data constituting one ECC block is recorded are normally reproduced, highly reliable data can be obtained only by the horizontal error correction processing.

However, the 16 sector fields in which data constituting one ECC block is recorded are not always reproduced normally. If 16 sector fields in which data constituting one ECC block are recorded are not normally reproduced, highly reliable data cannot be obtained only by horizontal error correction processing.

[0010] An object of the present invention is to process, when 16 sector fields in which data constituting one ECC block are recorded are not normally reproduced, the data which has not been normally reproduced as normal data. It is an object of the present invention to provide an error correction method capable of preventing the error correction.

It is another object of the present invention to provide a method in which, when 16 sector fields in which data constituting one ECC block are recorded are not normally reproduced, the data which has not been normally reproduced is replaced with a normal data. It is an object of the present invention to provide an optical disk device capable of preventing the processing from being performed as a process.

[0012]

In order to solve the above-mentioned problems and achieve the object, an error correction method and an optical disk apparatus according to the present invention are configured as follows. An error correction method according to the present invention includes a data block comprising a group of data arranged along a first direction and a second direction orthogonal to the first direction, wherein the first direction of the data block is First to correct the errors contained in the data
And a first step of generating a data block with an error correction code having a second error correction code for correcting an error included in the data in the second direction of the data block. First
A second step of correcting an error included in the data block by the first error correction code of the data block with the error correction code generated by the step of: Irrespective of whether or not the first
And a third step of correcting an error included in the data block using the second error correction code included in the data block with the error correction code generated in the step.

Further, the optical disk device of the present invention has a data block composed of a group of data arranged along a predetermined number of rows and columns, and a data block for correcting an error included in data in a column direction of the data block. N error correction codes, and N recording data units generated from an error correction code-attached data block having a second error correction code for correcting an error included in data in the row direction of the data block. Wherein one recording data unit recorded in one sector field among a plurality of sector fields provided on the optical disc is composed of M rows of data in the data block, A code assigned to data of M rows of the code, and the second error correction code. It has a code of 1 / N, these N
Reproducing means for reproducing N sector fields provided at predetermined positions on the optical disk on which the recording data units are recorded, and generating the data block with the error correction code based on the data reproduced by the reproducing means. A first error correction unit that corrects an error included in the data block by the first error correction code of the data block with the error correction code generated by the generation unit; 1
Regardless of whether or not the error has been completely corrected by the error correction by the error correction means, the data block is included in the data block by the second error correction code of the data block with the error correction code generated by the generation means. Second error correcting means for correcting an error to be corrected.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. First, the structure of data recorded on the DVD-RAM and the structure of data reproduced from the DVD-RAM will be described with reference to FIGS. FIG. 1 is a diagram schematically showing a data structure of an ECC block. FIG. 2 is a diagram schematically showing a data structure of a recording data unit.

A track for recording data is formed on the DVD-RAM, and a plurality of sector fields for recording data of a predetermined unit are formed on the track. The DVD-RAM is configured to record data in a format called an ECC block. Strictly speaking, 16 recording unit data generated from the ECC block are distributedly recorded in 16 sector fields.

As shown in FIG. 1, the ECC block is composed of a data block DB (collection of user data), a horizontal error correction code ECC1, and a vertical error correction code ECC2.

The data block DB is composed of data arranged along a predetermined number of rows and columns, and this data block can be divided into 16 data units DU. More specifically, the data block DB is composed of 172 (the number of bytes) × 12 (the number of rows constituting the data unit) × 16 (the number of data units constituting the data block). The data unit DU is composed of 172 (the number of bytes) × 12 (the number of rows constituting the data unit). Further, the data unit DU contains an error detection code EDC (Error Detection Code). The error detection code EDC is for detecting an error included in a group of a part of data in the data unit.

The horizontal error correction code ECC1 corrects an error contained in column data of the data block DB. More specifically, the horizontal error correction code ECC1 is 10 (bytes) × 1
It is composed of 2 (the number of rows constituting the data unit DU) × 16 (the number of data units DU constituting the data block DB) data.

The vertical error correction code ECC2 corrects an error contained in data in the row direction of the data block DB. More specifically, the vertical error correction code ECC2 is $ 172 (byte)
+10 (bytes)｝ × 16 (the number of data units DU constituting the data block DB).

Next, the recording data unit RDU will be described with reference to FIG. Sixteen recording data units RDU are generated from one ECC block. One recording data unit RDU includes a data unit DU, a part of a horizontal error correction code ECC1 given to the data unit DU, and a part of a vertical error correction code ECC2. I have. More specifically, the recording data unit R
DU is {172 (bytes) +10 (bytes)} × 12
(The number of rows constituting the data unit DU) +1 (for one column of the vertical error correction code ECC2).

Next, a schematic configuration of an optical disk device according to an embodiment of the present invention will be described with reference to FIG. The optical disk device shown in FIG. 3 performs a DVD-ROM, a DVD-V
video, DVD-R, music CD, CD-ROM, C
Reproduction processing can be performed on the DR and CD-RW.

This optical disk device performs recording and reproduction on a DVD-RAM, a DVD-ROM, and a DVD-Video.
o, DVD-R, music CD, CD-ROM, CD-
R, CD-RW
A system optical system and a signal processing system are provided. In other words, this optical disk device has a DVD optical system and a signal processing system,
And a CD optical system and a signal processing system.

The optical disk device is provided with a spindle motor 12, and the optical disk 10 is rotated by the spindle motor 12. Further, the optical disk device includes an objective lens actuator 70,
And an optical pickup 32. The optical pickup 32 irradiates the optical disk 10 with a light beam and detects reflected light from the optical disk. The light beam emitted from the optical pickup 32 is focused on the optical disc 10 via the objective lens actuator 70. That is, the reflected light of the collected light beam is detected by the optical pickup 32.

Here, the optical pickup 32 will be described with reference to FIG. As shown in FIG. 4, the optical pickup 32 includes a first semiconductor laser 98 for DVD and a CD.
A second semiconductor laser 99 for use. The first semiconductor laser 98 generates a laser beam having a wavelength of, for example, 650 nm. The second semiconductor laser 99 is, for example,
A laser beam having a wavelength of 780 nm is generated.

The laser beam emitted from the first semiconductor laser 98 is collimated by the collimator lens 96, reflected by the beam splitter 95, passes through the beam splitter 93, and is guided out of the optical pickup 32. On the other hand, the laser beam emitted from the second semiconductor laser 99 is collimated by the collimator lens 97, passes through the beam splitters 95 and 93, and is guided to the outside of the optical pickup 32.

The laser beam guided from the optical pickup 32 is supplied to a first objective lens 34 and a second objective lens 3.
5, and the laser beam is focused on the recording track of the optical disk 10 by the first objective lens 34 or the second objective lens 35. The laser beam reflected from the optical disk 10 is returned to the optical pickup 32 via one of the first objective lens 34 and the second objective lens 35 again.

In the optical pickup 32, the laser beam is reflected by the beam splitter 93 and is condensed by a condenser lens 91.
, And are divided into two systems by a beam splitter 90, and detected by a first photodetector 94a for DVD and a second photodetector 94b for CD. And
A DVD-based focus error signal, tracking error signal, reproduction signal (sum signal), and the like are generated by a signal output from the first photodetector 94a. On the other hand, a signal output from the second photodetector 94b generates a focus error signal, a tracking error signal, a reproduction signal (sum signal), and the like of the CD system.

Using the above-mentioned focus error signal, a positional shift of the first objective lens 34 or the second objective lens 35 in the focus direction is detected, and the first objective lens 34 or the second objective lens is corrected so as to correct the positional shift. A current is supplied to a coil (not shown) that moves the lens 35 in the optical axis direction. In addition, a positional deviation of the first objective lens 34 or the second objective lens 35 in the track direction is detected by using the track error signal, and the first objective lens 34 or the second objective lens 3 is corrected so as to correct the positional deviation.
Current is supplied to a coil that moves the disk 5 in the radial direction of the disk. In this way, information is recorded on the recording track of the optical disk 10, and the information is read from the recording track of the optical disk 10.

Here, returning to FIG. 2, the schematic description of the optical disk apparatus will be resumed. The optical disk device has a CPU
55, a ROM 54, and a RAM 53 are provided.
The CPU 55 controls each unit of the optical disk device based on a control program stored in the ROM 54. Also, RA
Necessary data is temporarily stored in M53.

Further, the optical disk device is provided with a laser control unit 40 for controlling the driving of the first semiconductor laser 98 and the second semiconductor laser 99. This laser controller 4
0 controls the driving of the first semiconductor laser 98 and the second semiconductor laser 99 in the DVD mode and the CD mode based on an instruction from the CPU 55. DVD mode is DV
In this mode, data processing (recording, reproduction, and erasing) is performed on D. The CD mode is a mode for executing data processing (reproduction) for a CD.

The DVD mode described above includes a DVD-RA
Recording mode for recording data on M, DVD-RA
An erasing mode for erasing data recorded on M and a reproducing mode for reproducing data recorded on various DVDs are included. When the DVD mode is executed in the laser control unit 40, the first semiconductor laser 98 is driven.
At this time, the laser power emitted from the first semiconductor laser 98 is controlled to a laser power suitable for each of the recording mode, the erasing mode, and the reproducing mode. In the recording mode, the driving of the first semiconductor laser 98 is controlled based on the recording data (strictly speaking, the data of the recording data unit RDU shown in FIG. 2) output from the DVD data processing unit. Thereby, the DV loaded in the optical disc device is
Recording data output from the DVD data processing unit is recorded in the D-RAM.

The CD mode includes a reproduction mode for reproducing data recorded on various CDs. When the laser control unit 40 executes the CD mode, the second semiconductor laser 99 is driven. At this time, the laser power emitted from the second semiconductor laser 98 is controlled to a laser power suitable for the reproduction mode.

In the optical disk device, the optical disk is directly
Alternatively, a tray 62 for mounting an optical disk stored in the disk cartridge 11 is provided. The tray 62 includes a first objective lens 34 and a second objective lens 35.
The loaded optical disk 10 is conveyed into the optical disk device so that the optical disk 10 is arranged facing the optical disk.

The optical disk device is provided with a tray motor 60 for driving the tray 62. The optical disk 10 loaded in the optical disk device has a stamper 6
3 and is rotatably held on a spindle motor 61 by the spindle motor 61. The optical pickup 32 is mounted on a feed mechanism (not shown) driven by a feed motor 56, and is moved in the radial direction of the optical disk 10 by the feed mechanism.

The signals (current signals) output from the first photodetector 94a and the second photodetector 94b provided in the optical pickup 32 are supplied to the current / voltage converter 4
1 converts it into a voltage signal. The converted voltage signal is supplied to the reference amplifier 42 and the servo amplifier 43.

The reference amplifier 42 outputs a reproduced signal as a sum signal (focus sum signal or tracking sum signal). DV in the laser control unit 40
When the D mode is executed, the output from the reference amplifier 42 is supplied to the DVD data processing unit 46. When the CD mode is executed in the laser control unit 40, the output from the reference amplifier 42 is C
It is supplied to the D servo seek control unit and the CD data processing unit 49.

The servo amplifier 43 generates a focus error signal and a tracking error signal based on the voltage signal converted by the current / voltage converter 41. The focus error signal is a signal corresponding to the focus state of the light beam emitted from the first semiconductor laser 98 or the second semiconductor laser 99. The tracking error signal is the first
It is a signal corresponding to the tracking state of the light beam emitted from the semiconductor laser 98 or the second semiconductor laser 99. That is, the servo amplifier 43 outputs a focus error signal and a tracking error signal. When the DVD mode is executed in the laser control unit 40, the output from the servo amplifier 43 is
It is supplied to the servo seek control unit 48. Laser controller 4
0, when the CD mode is executed, the servo
The output from the amplifier 43 is supplied to a CD servo seek control unit and a CD data processing unit 49.

The DVD servo seek control unit 48 generates a focus signal and a tracking signal for controlling the focus / tracking actuator driver and the feed motor driver 57 based on the focus error signal and the tracking error signal supplied from the servo amplifier 43. Generate. Further, a DVD servo seek control unit 4
8 generates an access signal based on a disk access instruction supplied from the CPU 55. The focus signal, the tracking signal, and the access signal generated by the DVD servo seek control unit 48 correspond to the focus / tracking actuator driver and the feed motor driver 5.
7. The focus / tracking actuator driver and the feed motor driver 57 perform focus servo control and tracking servo control of the first objective lens 34 based on the focus signal and the tracking signal supplied from the DVD servo seek control unit 48.
Further, the focus / tracking actuator driver and the feed motor driver 57 control the drive of the feed motor 56 based on the access signal supplied from the DVD servo seek control unit 48.

The CD servo seek control section and the CD data processing section 49 perform the following based on the focus error signal and the tracking error signal supplied from the servo amplifier 43.
A focus signal and a tracking signal for controlling the focus / tracking actuator driver and the feed motor driver 57 are generated. Further, the CD servo seek control unit and the CD data processing unit 49
An access signal is generated based on the disk access instruction supplied from the control unit 5. CD servo seek control unit and C
The focus signal, tracking signal, and access signal generated by the D data processing unit 49 are supplied to a focus / tracking actuator driver and a feed motor driver 57. The focus / tracking actuator driver and the feed motor driver 57 are a CD
Based on the focus signal and tracking signal supplied from the servo seek control unit and the CD data processing unit 49,
Focus servo control and tracking servo control of the second objective lens 34 are performed. Further, a focus / tracking actuator driver and a feed motor driver 5
7 is a CD servo seek control unit and a CD data processing unit 4
9 based on the access signal supplied from the feed motor 5.
6 is controlled.

The spindle motor 61 is controlled by a spindle motor driver 58. The control of the spindle motor 61 by the spindle motor driver 58 is as follows.
The processing is executed based on data supplied from the DVD data processing unit or data supplied from the CD servo seek control unit and the CD data processing unit 49. The tray motor 60 is
It is controlled by the tray motor driver 59. The control of the tray motor 60 by the tray motor driver 59 is executed based on data supplied from the DVD data processing unit 46 or the CPU 55.

The DVD data processing section 46 executes a data recording process and a data reproducing process based on an instruction from the CPU 55. The data recording process is a process of generating recording data based on user data input via the SCSI interface control unit 50 and supplying the generated recording data to the laser control unit 40. Here, the data recording process will be described in more detail. User data input via the SCSI interface control unit 50 is data included in the data block DB in FIG. That is, based on the user data input via the SCSI interface control unit 50, the EC shown in FIG.
A C block is generated. Furthermore, this generated EC
Based on the C block, 16 recording data units R
A DU is generated. Then, the recording data unit RDU is supplied to the laser control unit 40.

On the other hand, the data reproduction process is a process of generating reproduction data based on a reproduction signal supplied from the reference amplifier 42 and stored in the RAM 47, and supplying the generated reproduction data to the SCSI interface control unit 50. is there. Here, the data reproducing process will be described in more detail. Upon receiving the reproduced signal supplied from the reference amplifier 42, the reproduced signal is stored in the RAM 47. Here, the DVD data processing unit 46 reads the reproduction signal stored in the RAM 47, that is, the recording data unit RD.
An ECC block is generated based on a reproduced signal corresponding to U. Further, a vertical error correction process is performed based on the vertical error correction code ECC1 included in the generated ECC block, and a horizontal error correction process is performed based on the horizontal error correction code ECC2.
Further, an error detection process is performed based on the error detection code EDC included in the data unit DU of the ECC block. After these series of processes are performed, E
The user data included in the data block DB of the CC block is output to the external device via the SCSI interface control unit 50. The external device is a personal computer or the like. The RAM 51 functions as a SCSI interface control unit and a buffer for the CD-ROM decoder 50.

The CD servo seek control section and the CD data processing section 49 receive the reproduction signal supplied from the reference amplifier 42 and perform predetermined processing on the reproduction signal. The reproduction signal subjected to the predetermined processing is supplied to the SCSI interface control unit and the CD-ROM decoder 50, and is output to an external device via the SCSI. The reproduction signal reproduced from the music CD is supplied from the CD servo seek control section and the CD data processing section 49 to the CD data output amplifier 52. The CD data output amplifier 52 outputs an audio based on a reproduction signal reproduced from the music CD.

Next, referring to the flowchart of FIG.
The flow of the data reproducing operation will be described. First, data is reproduced from (16 × N) sector fields on the optical disk (ST12). That is, the recording data unit RDU recorded in the sector field provided on the optical disc is reproduced. The ECC block shown in FIG. 1 is generated based on the reproduction data obtained by this reproduction (ST14). Since the data recorded on the optical disk has been subjected to a predetermined modulation process (8-16 modulation), the reproduction data reproduced from the optical disk is subjected to a predetermined demodulation process. These modulation processing and demodulation processing are performed in the DVD data processing unit 46.

Subsequently, the DVD data processing unit 46
Vertical and horizontal error correction processing and error detection processing are executed. First, the count value (N) of the error correction counter is set to 0 (ST16). This error correction counter is a counter that counts the number of times the vertical and horizontal error correction processes are executed at a specific timing. When a predetermined number of error correction processes are counted by the error correction counter, the error correction process is stopped. This error correction counter is
It is assumed that the DVD data processing unit 46 is provided.

On condition that the count value of the error correction counter has not reached the predetermined number (MAX) (ST18,
NO), a horizontal error correction process is performed (ST2).
0). That is, the error correction process in the row direction of the data block DB is performed by the horizontal error correction code ECC1 included in the ECC block. The horizontal error correction code ECC1 has a maximum of 4 per column.
It has error correction capability to correct errors up to bytes. That is, it is not possible to correct an error in a data string including an error of 5 bytes or more. Therefore, an error flag indicating that error correction has not been processed is set for a data string including an error of 5 bytes or more.

When an error flag is set by the error correction process in ST20 (ST22, YES), the count value of the error correction counter is incremented by one (ST24). Then, a vertical error correction process is performed (ST26). That is, the error correction process in the column direction of the data block DB and the horizontal error correction code ECC2 is executed by the vertical error correction code ECC2 included in the ECC block. The vertical error correction code ECC2 has a maximum of one per line.
It has an error correction capability for correcting errors up to 6 bytes. That is, it is not possible to correct an error in a data row containing an error of 17 bytes or more. Therefore, an error flag indicating that error correction has not been processed is set for a data line containing an error of 17 bytes or more.

If an error flag is set by the error correction processing in ST26 (ST28, YES), the count value of the error correction counter is incremented by one (ST30). At this time, on the condition that the count value of the error correction counter has not reached the predetermined number of times (MAX) (ST18, NO), the processes after ST20 are executed again. When the count value of the error correction counter reaches a predetermined number (M
AX) (ST18, YE
S), a reproduction error occurs (ST32). This means that errors contained in the reproduced data cannot be corrected. As described above, the error of the reproduction data is corrected by repeating the horizontal and vertical error correction processes until the error flag disappears.

If the error flag is not set by the error correction processing in ST20 (ST22, NO), S
A vertical error correction process similar to T26 is performed (ST34). When an error flag is set by this vertical error correction processing (ST36, YE
S), a reproduction error occurs (ST32). In this case,
Assuming that the 16 sector fields in which data constituting one ECC block are dispersedly recorded are not normally reproduced, the data reproducing operation is restarted. That is, the process is repeated from ST12.

The reason why the 16 sector fields in which the data constituting one ECC block are dispersedly recorded are regarded as not being normally reproduced is that the error correction has been completed by the horizontal error correction processing. This is because the error was corrected again by the vertical error correction processing. If the 16 sector fields in which the data constituting one ECC block are dispersedly recorded are normally reproduced, and the error correction is completed by the horizontal error correction processing, no error is included in the reproduced data. Should be. Nevertheless, the error is corrected again by the vertical error correction process only for one E.
This means that 16 sector fields in which data constituting the CC block are dispersedly recorded are not normally reproduced.

For example, the data constituting the ECC block A is composed of the sector fields SFA1 to S
It is assumed that distributed recording is performed in 16 sector fields of the FB 16. Further, the data constituting the ECC block B is composed of sector fields SFB1 to SF1.
It is assumed that data is distributed and recorded in 16 sector fields of B16. Under such a situation, it is assumed that 16 sector fields of the sector fields SFA1 to SFA15 and the sector field SFB1 are erroneously reproduced as one ECC block. In such a case, even if the error correction is completed by the horizontal error correction processing, an error is found by the vertical error correction processing. This is due to the characteristic of the data structure of the recording data unit RDU shown in FIG.

Data constituting one ECC block is not always recorded in 16 consecutive sector fields. There is also a defective field in the sector field provided on the optical disc. No data is recorded in such a defective field. That is, data constituting one ECC block is dispersedly recorded in 16 sectors excluding such a defective field. Under such circumstances, one ECC
The 16 sector fields in which the data constituting the block are dispersedly recorded may not be properly reproduced.

If the error flag is not set in the vertical error correction processing in ST34 (ST3
6, NO), an error detection process is executed (ST3).
8). That is, the error included in the data unit DU is detected by the error detection code EDU included in the data unit DU of the ECC block. If no error is detected by this error detection processing (ST40, N
O), the reproduction data is transferred to the external device (ST)
42). If an error is detected by this error detection processing (ST40, YES), a reproduction error occurs (ST3).
2).

According to the present invention, as described above, by always performing the horizontal and vertical error correction processing, 16 sector fields in which data constituting one ECC block are dispersedly recorded are normally reproduced. If not, a reproduction error can be detected. Thereby, the reliability of the reproduced data can be improved.

[0055]

According to the present invention, the following error correction method and optical disk device can be provided. (1) When 16 sector fields in which data constituting one ECC block are dispersedly recorded are not normally reproduced, the data which is not reproduced normally is prevented from being processed as normal data. Error correction methods that can be used.

(2) When 16 sector fields in which data constituting one ECC block are dispersedly recorded are not normally reproduced, the data which has not been normally reproduced is processed as normal data. An optical disk device that can prevent the occurrence of an error.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a data structure of an ECC block.

FIG. 2 is a diagram schematically showing a data structure of a recording data unit.

FIG. 3 is a block diagram illustrating a schematic configuration of an optical disc device according to an embodiment of the present invention.

FIG. 4 is a diagram showing a schematic configuration of an optical pickup.

FIG. 5 is a flowchart showing a flow of a reproducing operation.

[Explanation of symbols]

 Reference Signs List 10 optical disk 32 optical pickup 42 reference amplifier 43 servo amplifier 46 DVD data processing unit 53 RAM 54 ROM 55 CPU

Claims (6)

[Claims] 1. A data block comprising a group of data arranged along a first direction and a second direction orthogonal to the first direction, wherein the first one of the data blocks is
A first error correction code for correcting an error included in the data of the data block, and an error correction code having a second error correction code for correcting an error included in the data of the data block in the second direction. A first step of generating a data block with a code, and a step of correcting an error included in the data block with the first error correction code of the data block with the error correction code generated in the first step. Step 2 and the second error correction of the data block with the error correction code generated by the first step, regardless of whether the error has been corrected by the error correction of the second step. A third step of correcting an error contained in the data block by a code; Error correction method which is characterized in that there was example. 2. An error detecting block which is composed of a group of data arranged along a first direction and a second direction orthogonal to the first direction, and which detects an error included in a part of the group of data. A data block including a detection code, a first error correction code for correcting an error included in the data in the first direction of the data block, and a first error correction code included in the data of the second direction of the data block A first step of generating a data block with an error correction code having a second error correction code for correcting an error to be read; and a first step of the data block with an error correction code generated by the first step. A second step of correcting an error included in the data block by using an error correction code; Irrespective of whether or not the error has been completely corrected by the error correction, the error included in the data block is determined by the second error correction code included in the data block with the error correction code generated in the first step. After a third step of correcting, and the second and third steps, it is determined that the data block included in the data block with the error correction code generated in the first step does not include an error. And a fourth step of detecting an error contained in a part of the data set by using the error detection code contained in the data block. 3. A data block comprising a group of data arranged along a predetermined number of rows and columns, a first error correction code for correcting an error contained in data in a column direction of the data block, and A second step of correcting an error included in data in a row direction of the data block.
N recording data units generated from an error correction code-added data block having the following error correction code, wherein one record is recorded in one of a plurality of sector fields provided on the optical disc. A data unit for data of M rows of the data block, a code assigned to data of M rows of the first error correction code, and a second error correction code. A first step of reproducing N sector fields provided at predetermined positions on an optical disk on which the N recording data units are recorded, the first step comprising: Based on the data reproduced by the steps,
A second step of generating the data block with the error correction code; and an error included in the data block by the first error correction code of the data block with the error correction code generated by the second step. A third step of correcting the error, and irrespective of whether or not the error has been completely corrected by the error correction of the second step, the third step of the data block with the error correction code generated in the second step. A fourth step of correcting an error included in the data block using the second error correction code. 4. A data block comprising a group of data arranged along a predetermined number of rows and columns and including an error detection code for detecting an error contained in a part of the group of data. An error correction code having a first error correction code for correcting an error included in data in a column direction of the data block and a second error correction code for correcting an error included in data in a row direction of the data block N recording data units generated from the appended data block, wherein one recording data unit recorded in one of a plurality of sector fields provided on the optical disc is a recording data unit of the data block. Of the M rows of data, and the M rows of data of the first error correction code. And N sector fields provided at predetermined positions on the optical disc having the given code and 1 / N of the second error correction code, and these N recording data units recorded thereon. A first step of reproducing, and based on the data reproduced in the first step,
A second step of generating the data block with the error correction code; and an error included in the data block by the first error correction code of the data block with the error correction code generated by the second step. A third step of correcting the error correction code; and irrespective of whether or not the error has been completely corrected by the error correction of the third step, the third step of the data block with the error correction code generated in the second step. A fourth step of correcting an error included in the data block by using the second error correction code; and a data block with the error correction code generated by the second step through the third and fourth steps. It has been found that the data block has no error. The an error detection code, the error correction method characterized by comprising: a fifth step, a detecting an error contained in the collection of part of the data contained in the data block. 5. A data block comprising a group of data arranged along a predetermined number of rows and columns, a first error correction code for correcting an error contained in data in a column direction of the data block, and A second step of correcting an error included in data in a row direction of the data block.
N recording data units generated from an error correction code-added data block having the following error correction code, wherein one record is recorded in one of a plurality of sector fields provided on the optical disc. A data unit for data of M rows of the data block, a code assigned to data of M rows of the first error correction code, and a second error correction code. A reproducing means for reproducing N sector fields provided at predetermined positions on an optical disk on which the N recording data units are recorded, wherein the reproduction data is reproduced by the reproducing means. Generating means for generating the data block with the error correction code based on the generated data; and First error correction means for correcting an error included in the data block by the first error correction code included in the data block with the error correction code; and error correction by error correction by the first error correction means. Second error correction means for correcting an error included in the data block by the second error correction code of the data block with the error correction code generated by the generation means, An optical disc device, comprising: 6. A data block comprising a group of data arranged along a predetermined number of rows and columns, and a data block including an error detection code for detecting an error contained in a part of the group of data, and the data block. An error correction code having a first error correction code for correcting an error included in data in a column direction of the data block and a second error correction code for correcting an error included in data in a row direction of the data block N recording data units generated from the appended data block, wherein one recording data unit recorded in one of a plurality of sector fields provided on the optical disc is a recording data unit of the data block. Of the M rows of data, and the M rows of data of the first error correction code. And N sector fields provided at predetermined positions on the optical disc having the given code and 1 / N of the second error correction code, and these N recording data units recorded thereon. A reproducing unit that reproduces the data, a generating unit that generates the data block with the error correction code based on the data reproduced by the reproducing unit, and a data unit that has the data block with the error correction code generated by the generating unit. A first error correction unit for correcting an error included in the data block by using one error correction code; and irrespective of whether or not the error has been completely corrected by the first error correction unit. The second error correction code included in the data block with the error correction code generated by the means A second error correction unit that corrects an error included in the data block; and an error correction process performed by the first and second error correction units. The data with the error correction code generated by the generation unit. When it is determined that the data block has no error in the data block, the error detection code included in the data block detects an error included in a group of some data, based on the error detection code. An optical disc device, comprising: