JP2001291330A - Optical recording medium, information recording device, and information reproducing device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To facilitate recording and reproduction by performing optimal error correction processing. SOLUTION: Main data obtained by subjecting an information signal to be recorded to error correction processing including interleaving processing and a subcode including access information for the main data are recorded on a recording track. Error correction information relating to the error correction processing is recorded in the subcode. This makes it easy to determine what kind of error correction processing is performed and error correction is performed during reproduction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk-shaped optical recording medium on which information signals are recorded and / or reproduced along recording tracks. Further, the present invention relates to an information recording device for recording an information signal on such an optical recording medium and an information reproducing device for reproducing the information signal.

[0002]

2. Description of the Related Art An optical recording medium is formed in a disk shape with a signal recording layer. By irradiating the signal recording layer with a light beam, recording and / or reproduction of an information signal (hereinafter referred to as an information signal) is performed. , Recording and reproduction).

As such an optical recording medium, for example, C
D (Compact Disc) and CD-ROM (CD-Read Only Mem)
ory), there is a read-only optical disk in which pit strings corresponding to information signals to be recorded are formed in advance on a disk substrate. In such a read-only optical disk, the main surface on the disk substrate on which the pit array is formed has a function as a signal recording layer.

[0004] For example, an optical disk (hereinafter, referred to as a CD-R) to which an information signal can be additionally written has been put to practical use, which is used in a so-called compact disk recordable system. In a CD-R, a signal recording layer on which an information signal is recorded is formed of an organic dye-based material, and recording is performed by irradiating a light beam to change the reflectance at this irradiation position. The recorded signal is reproduced by detecting the reflectance of the signal recording layer.

As an optical recording medium, CD-RW
Phase-change optical disks, such as (CD-Rewritable), in which a recording signal can be rewritten using a phase change of a signal recording layer, have been put to practical use.

[0006] CD, CD-ROM, CD as described above
Various specifications of an optical disc such as -R and CD-RW are standardized by a standard called a CD format. As a result, a CD-R or CD-RW on which an information signal can be additionally written or rewritten can be used for a read-only CD or CD-R.
It is also possible to reproduce the data by a device for reproducing the D-ROM.

[0007]

The above-mentioned C
In the D format, the information signal to be recorded is CIRC (Cr
oss Interleave Reed-Solomon Code) is subjected to an error correction coding process by a convolutional double coding including an interleave process, and is subjected to EFM modulation (Eight to Fourth).
en Modulation) is performed on the recording track. Then, when reproducing the optical disk, the recorded information signal is expanded by the CIRC and error correction is performed, and the main data included in the information signal is read.

[0008] However, for example, the CD, C
In order to realize a large-capacity optical disc by further increasing the recording density while ensuring compatibility with optical discs such as D-ROM, CD-R, and CD-RW, a conventional optical disc is used. If the same CIRC format is used, there is a possibility that error correction cannot be performed sufficiently. For this reason, it is necessary to perform stronger error correction than before by, for example, changing the unit delay amount in the CIRC interleaving process from “4” to “7” according to the increase in recording density.

In this case, the optical disc apparatus is designed to cope with both conventional optical discs and optical discs with a high recording density by interleaving information signals recorded on the optical discs in any CIRC format. It is necessary to determine whether At this time, for example, an error correction using a plurality of CIRC formats is attempted, and an operation of estimating the format with the lowest error correction number as the CIRC format of the optical disc is performed.

However, when recording and reproducing data on and from a plurality of optical discs having different CIRC formats, as described above, there is a problem that it takes a lot of time to repeat trials using a plurality of CIRC formats. Will happen. In addition, the number of error corrections may be increased due to dust or scratches attached to the surface of the optical disk, and it is expected that it will be difficult to select a CIRC format that matches the optical disk. Is done.

The present invention has been made in view of the above circumstances, and has as its object to provide an optical disk which can be easily subjected to optimal error correction processing and recorded and reproduced. It is another object of the present invention to provide an information recording device for recording an information signal on such an optical disc and an information reproducing device for reproducing the information signal.

[0012]

An optical recording medium according to the present invention is a disk-shaped optical recording medium on which information signals are recorded and / or reproduced along recording tracks. The recording track has main data in which an information signal to be recorded has been subjected to error correction processing including interleaving processing,
A subcode including access information for the main data is recorded. And in the above subcode,
Error correction information regarding the error correction processing is recorded.

In the optical recording medium according to the present invention configured as described above, since error correction information is recorded in the subcode, what kind of information is recorded and reproduced when the optical recording medium is recorded and reproduced by the optical disc device. It is possible to easily determine whether to perform error correction processing and perform error correction.

Further, an information recording apparatus according to the present invention is an information recording apparatus for recording an information signal on a disk-shaped optical recording medium along a recording track. And it has a signal processing means, a rotation driving means, and a recording means. The signal processing means generates main data obtained by subjecting an information signal to be recorded to an error correction process including an interleave process, and access information for the main data, and a subcode including error correction information relating to the error correction process. The rotation driving means rotationally drives the optical recording medium at a predetermined speed. The recording means is movable in the radial direction of the optical recording medium, and records the main data and the subcode on the optical recording medium.

The information recording apparatus configured as described above has
When recording on an optical recording medium, error correction information relating to error correction processing can be recorded in the subcode. Therefore, when reproducing this optical recording medium,
It is possible to easily determine what kind of error correction processing is performed and error correction is performed.

Further, an information reproducing apparatus according to the present invention is an information reproducing apparatus for reproducing an information signal recorded along a recording track on a disk-shaped optical recording medium.
And it has rotation drive means, detection means, and signal processing means. The rotation driving means rotationally drives the optical recording medium at a predetermined speed. The detecting means is movable in the radial direction of the optical recording medium and detects an information signal recorded on a recording track of the optical recording medium. The signal processing means expands, from the information signal detected by the detection means, main data subjected to error correction processing including interleaving processing, and a subcode including access information for the main data, and Error correction of the main data is performed based on the error correction information regarding the error correction process included therein.

In the information reproducing apparatus according to the present invention having the above-described configuration, when reproducing the information signal recorded on the optical recording medium, based on the error correction information recorded in the subcode, the main information is reproduced. Data error correction can be performed. Therefore, even when each optical recording medium is recorded using a different error correction processing, it is possible to appropriately select an error correction processing suitable for the optical recording medium and quickly and surely reproduce the data. it can.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical recording medium, an information recording apparatus, and an information reproducing apparatus to which the present invention is applied will be described.
This will be described in detail with reference to the drawings. In the following,
As an example of an optical recording medium to which the present invention is applied, an existing CD
A CD-R of a double density CD format newly defined for the format (hereinafter, referred to as a double density CD-R) will be described. Further, as an information recording apparatus and an information reproducing apparatus to which the present invention is applied, an optical disk apparatus that records and reproduces an information signal on and from the above-described double-density CD-R will be described as an example.

The present invention is not limited to application to a double-density CD-R, but may be applied to, for example, a read-only optical disk, various write-once optical disks, a phase change optical disk, and the like. Good. Specifically, for example,
Like the double-density CD-R described below, the present invention may be applied to a newly defined double-density CD-format CD-RW. Also, the present invention is not limited to the recording density of the optical disc.

The various specifications of the CD-R are standardized under the name of the so-called Orange Book Part 2 (Orange Book Part II).
Only the differences between the DR (hereinafter, referred to as a 1 × density CD-R) and the 2 × density CD-R will be described.

The CD-R is, as shown in FIGS. 1 and 2,
A resin material such as polymethyl methacrylate (PMMA) or polycarbonate (PC) has an outer diameter of φ120 mm,
A disk substrate 1 formed into a disk having a thickness of 1.2 mm is provided, on which a signal recording layer 2 formed by spin coating an organic dye-based recording material is formed. On the signal recording layer 2, for example, Au, A
The reflective layer 3 is formed by depositing g, Al or the like, and a protective layer 4 is formed on the reflective layer 3 by, for example, spin-coating an ultraviolet curable resin or the like.

In this CD-R, a recording light beam modulated in accordance with data to be written (hereinafter, referred to as recording data) is applied to the signal recording layer 2 so that a portion irradiated with the light is irradiated. Interaction between the signal recording layer 2 and the disk substrate 1 in contact therewith causes deformation at these interfaces, whereby a recording mark corresponding to recording data is formed irreversibly. Then, the recording mark is irradiated with a light beam for reproduction, and the change in the reflectance is detected, so that the data written on the CD-R is read.

As shown in FIGS. 2 and 3, a pregroove 5, which is a meandering guide groove, is formed in a portion serving as a data recording area of the disk substrate 1, for example, in a spiral shape. A portion corresponding to the pre-groove 5 of the signal recording layer 3 is set as a recording track, and user data or the like that has been subjected to error correction encoding processing or EFM modulation processing is recorded on this recording track. It has been done. Therefore, in this CD-R, as shown in FIG. 3, the interval between adjacent pregrooves 5 is the track pitch TP.

The pre-groove 5 is formed so as to meander (wobble) in a slightly sinusoidal manner. By this wobbling, FM-modulated position information, that is, time-axis information indicating an absolute position on the disk, etc. But A
It is recorded as a TIP (Absolute Time In Pregroove) wobble signal.

The ATIP wobble signal has a center frequency of, for example, 2 when the CD-R is rotationally driven at a predetermined speed.
It is recorded so as to be 2.05 kHz. ATIP
One sector of the wobble signal matches one data sector (2352 bytes) of the user data. When writing the user data, the writing is performed while synchronizing the data sector of the user data with the sector of the ATIP wobble signal. Is performed.

Next, the recording format of the CD-R will be described. FIG. 4 shows the recording format of the CD-R. Note that the recording format shown in FIG. 4 is an example in which recording data is written by a recording method in which a plurality of logical tracks are added as needed, that is, a method called Track At Once.

As shown in FIG. 4, in the data recording area of the CD-R, the PC
A (Power Calibration Area) 11 and PMA (Progra
m, a lead-in area 13, a plurality of logical tracks 14 a, 14 b, 14 c (hereinafter collectively referred to as a logical track 14), and a lead-out area 15. Although FIG. 4 shows a recording format in the case where data is written by the track-at-once method, in a CD-R, for example, the lead-in area 13, the logical track 14, and the lead-out area 15 are set as one session. Alternatively, the recording data may be written by a recording method for writing a plurality of sessions, that is, a method called Session At Once.

The PCA 11 is an area for calibrating the power of the light beam at the time of recording, and has a test area for actually performing test writing and a count area for recording the use state of this test area. are doing. Also, PM
A12 is an area for temporarily storing information such as a mode of data to be written (the mode will be described in detail later), a recording start position, a recording end position, and the like. The PCA 11 and the PMA 12 are areas that are required only at the time of recording. When the finalizing operation of writing information on the written logical track into the lead-in area 13 is completed, the optical pickup of the optical disk device may access during reproduction. Absent.

The lead-in area 13 is a logical track 1
4 is an area used for reading the recording data written in, for example, TOC (Table Of Contents) information and the like. In the CD-R, the TOC information written in the lead-in area 13 is read at the time of reproduction, so that the optical pickup can instantaneously access a desired recording track.

The plurality of logical tracks 14a, 14b, 14
In c, a program area 16 in which user data is written and a buffer area set at the head position of the program area 16, that is, a pre-gap 17, are set.

The lead-out area 15 is an area in which various information relating to the disc is recorded. Also, the optical pickup has a function of preventing the optical pickup of the optical disk device from overrunning outside the outer periphery of the disk.

Next, the format of the recording data recorded on the CD-R will be described. The user data recorded on the CD-R is CIRC (Cross Interleave Reed-So
lomon Code), which is subjected to error correction coding processing by convolutional double coding, and is subjected to EFM modulation (Eight to F
Ourteen Modulation) is written.

In the error correction coding process by the CIRC, a Reed-Solomon code (C2 code) is coded for each data unit of 24 bytes (12 words), and a 4-byte parity (Q parity) is added. . Then, after interleave processing is performed on user data and Q parity of a total of 28 bytes, Reed-Solomon code (C1 code) is encoded, and a 4-byte parity (P parity) is further added. , A total of 32 bytes of data. Here, the interleaving process is a process of giving a delay of 0, D, 2D, 3D,... 27D to data of, for example, 28 symbols (24 symbols + 4 symbols). Here, D indicates a delay parameter (unit delay amount).

The error correction encoding processing by the CIRC adds a 4-byte Q parity and a 4-byte P parity to each 24-byte user data. A byte frame synchronization signal “Frame Sync” and a 1-byte subcode “Subcode” are added to form one frame as a data transmission unit as shown in FIG.

The subcode is composed of eight channels P to W, and one bit (one byte in total) is inserted for each channel for each frame. The subcode is completed as one piece of information with subcodes for 98 frames. As shown in FIG.
A data block (data sector), which is an access unit when the optical disk device accesses user data, is constituted by 98 frames, which is a data unit in which a subcode is completed. The rest of one data block is main data “Main Data” including user data.

The user data contained in one data block is a total of 2352 bytes (24 bytes × 98). As shown in FIG. 7, a 12-byte block synchronization signal “Block Sync” is provided at the beginning of the data. And a 4-byte block header “Block Header”. In the block header, the block address “Block Address” is indicated by three bytes, and the remaining byte is a mode byte “Mode Byt” indicating the attribute of the block.
e ".

The subcode contained in one data block is a total of 98 bytes of data. As shown in FIG. 8, the subcode synchronization signals “S ₀ ” and “S ₁ ” of 2 bytes are placed at the beginning of the subcode. "have. The remaining 96 bytes are allocated to each of the channels P to W. Of these channels, the P channel and the Q channel include access information such as absolute time information and address information used for accessing the data block to which the subcode belongs.
The channel includes, for example, a mode of the data block to which the subcode belongs (the mode will be described later in detail), information indicating an item, an instruction, and the like, and accompanying data.

The double-density CD-R according to the present invention has the above-described configuration, ensures compatibility with the conventional single-density CD-R, and relates to the above-described error correction processing. Error correction information is recorded in the subcode. This makes it possible to determine what error correction processing is to be performed on the main data to perform error correction based on the error correction information recorded in the subcode when the data is reproduced by the optical disk device. That is, before performing the error correction processing by the CIRC on the main data, it is possible to determine the error correction information regarding the error correction processing when the subcode is read.

Therefore, for example, even when an optimum CIRC format for sufficiently correcting an error is selected and recorded in accordance with an increase in recording density, an error correction recorded in a subcode is not reproduced during reproduction. The error can be corrected based on the information, and the reproduction can be performed quickly and reliably.

As the error correction information, specifically, information indicating a unit delay amount in the interleave processing can be mentioned. For example, in the conventional single-density CD-R, the unit delay amount is “4”, but the double-density C-R
In the DR, the unit delay amount is set to “7”, and information indicating the unit delay amount is recorded in a subcode. By increasing the unit delay amount in the interleave processing as described above, the error correction capability for a larger burst error is improved. Therefore, in a double-density CD-R with a higher recording density, a single-density CD-R is used. It is effective to make the unit delay larger than R.

By applying the present invention, even when the information signal is recorded by changing the error correction processing according to the recording density of the CD-R, error correction relating to this error correction processing is performed. Since the information is recorded in the subcode of each CD-R, it is possible to perform an appropriate error correction process according to each CD-R when reproducing by the optical disk device.

It is desirable that the error correction information is recorded in a subcode in the lead-in area 13 including the TOC information. When a CD-R is mounted on an optical disk device and is played, the optical pickup of the optical disk device first reads the lead-in area 1.
3 is accessed and the TOC information is read. Therefore, since the error correction information is recorded in the sub-code in the lead-in area 13, if the error correction processing is changed according to the recording density, for example, the CD-R is a single-density CD-R. Yes, double density CD
The determination of -R can be performed immediately after the optical disk device is mounted.

It is desirable that the error correction information be recorded on the Q channel in the subcode. As described above, the Q channel of the subcode includes access information used for accessing the data block to which the subcode belongs. Similarly, the error correction information can be easily read.

Next, in the following, by applying the present invention, the double-density CD-R in which the error correction information is recorded in the subcode as described above is used for an optical disk device 20 as shown in FIG. The case where the information signal is recorded by using is described. In the following description, the optical disc device 20 is described as being capable of not only recording information signals on a double-density CD-R but also reproducing information signals recorded on a double-density CD-R. The present invention relates to a CD-
The present invention is not limited to the application to an optical disk device that performs recording and reproduction for R, but can be widely applied to an optical disk device that performs recording and reproduction of an information signal along a recording track on a disk-shaped optical recording medium. Needless to say.

As shown in FIG. 9, the optical disk device 20 includes a data recording system 21 for recording data supplied from a host computer or the like on the CD-R 100, and a CD-R 100.
A data reproducing system 22 for reproducing data recorded in the R100 and supplying the data to a host computer or the like.

The data recording system 21 is provided with an input terminal 23, from which data supplied from a host computer or the like is input. The data input from the input terminal 23 is CI
It is supplied to the RC encoder 24.

The CIRC encoder 24 includes a C2 encoder 25, a first interleaver 26 and a second interleaver 27, and a switch circuit 28 for switching between the first interleaver 26 and the second interleaver 27. And a C1 encoder 29.

The data input from the input terminal 23 is first supplied to the C2 encoder 25. The C2 encoder 25 performs C2 encoding on the supplied data, and for example, outputs 4 symbols of data for each 24 symbol data unit.
The parity Q of the Reed-Solomon code is added. The data to which the parity Q is added by the C2 encoder 25 is the first data.
Is supplied to one of the interleaver 26 or the second interleaver 27 selected by the switch circuit 28, and an interleave process is performed.

Here, the interleaving process is a process of giving a delay of 0, D, 2D, 3D,... 27D to data of, for example, 28 symbols (24 symbols + 4 symbols). Here, D indicates a delay parameter (unit delay amount).

The first interleaver 26 has a delay parameter D set to “4” (frame), and when data to which a parity Q is added is supplied, the maximum delay for this data is, for example, Interleave processing for 108 frames (27 × 4 frames) is performed. On the other hand, the second
Interleaver 27 has a delay parameter D of “7”
(Frame), and when data to which parity Q is added is supplied, the data is subjected to interleave processing with a maximum delay of, for example, 189 frames (27 × 7 frames).

The data subjected to the interleave processing by the first interleaver 26 or the second interleaver 27 is supplied to the C1 encoder 29. The C1 encoder 29 performs C1 encoding on the data sequence on which the interleave processing has been performed, and adds a parity P of a Reed-Solomon code to each of a plurality of data symbols.

The data subjected to the error correction coding by the CIRC by the above processing is supplied to the EFM modulation circuit 30, and after the EFM modulation circuit 30 performs EFM modulation (Eight to Fourteen Modulation), the write compensation circuit 31. At this time, the EFM modulation circuit 30 adds a subcode to the recording data to be written based on a control signal input from the control unit 43 described later. Then, a write signal from the write compensation circuit 31 is supplied to the optical pickup 32, and the optical pickup 32 records a signal corresponding to the recording data on the CD-R 100 as a recording mark sequence.

The recording system 2 of the optical disk device 20
1, two interleavers 26 and 27 are provided in the CIRC encoder 24 because the single density CD
This is because appropriate interleave processing is performed on both the -R and the double-density CD-R. That is, in the optical disc device 20, when data is recorded on a single-density CD-R, the first interleaver 26 is selected by the switch circuit 28 and supplied to the first interleaver 26. An interleave process for setting the delay parameter D to “4” is performed on the data thus obtained. Further, in the optical disc device 20, when data is recorded on a double-density CD-R, the second interleaver 27 is selected by the switch circuit 28 and supplied to the second interleaver 27. An interleaving process for setting the delay parameter D to “7” is performed on the data thus obtained.

Here, the error correction encoding process by the CIRC encoder 24 will be described with reference to FIG. In FIG. 10, m symbols are data units to be subjected to error correction coding processing, and r symbols are C units.
2 is a parity Q added by the C2 encoding process by the 2 encoder 25, and the s symbol is a C1 decoder 29.
Is a parity P added by the C1 encoding according to.

In FIG. 10, diagonal lines C2a and C2a
2b indicates a data string to be subjected to C2 encoding, and a vertical line C1 indicates a data string to be subjected to C1 encoding. As described above, the data string to be subjected to the C2 encoding is the oblique lines C2a and C2b because the first or second interleaver 26,
This is because the interleave processing is performed by the P.27.
That is, by performing the interleaving process by the first interleaver 26 on the data on which the C2 encoding has been performed, the data sequence becomes the direction indicated by the oblique line C2a in FIG. When the interleaved process is performed by the second interleaver 27 on the interleaved data, the data sequence becomes a direction indicated by an oblique line C2b in FIG.

In FIG. 10, a vertical line C
1 and θ2 of the oblique lines C2a and C2b with respect to 1
Corresponds to the delay parameter D set in the first interleaver 26 and the second interleaver 27, and since the delay parameter D of the first interleaver 26 is set to “4”, Since the inclination of the oblique line C2a with respect to the vertical line C1 is θ1, and the delay parameter D of the second interleaver 27 is set to “7”, the oblique line with respect to the vertical line C1 C2
The inclination of b is θ2. In FIG. 10, A indicates the maximum delay amount (interleave length) when the interleave process is performed by the first interleaver 26, and B indicates the interleave process performed by the second interleaver 27. Shows the interleave length in case of

From FIG. 10, the interleave length B when the delay parameter D is set to "7" and the interleave processing is performed is the interleave length B when the delay parameter D is set to "4" and the interleave processing is performed. It can be seen that the length is longer than the length A. This means
It is shown that by changing the delay parameter D from “4” to “7”, the ability to correct a burst error is improved.

Since the value of the delay parameter D is substantially proportional to the interleave length, the delay parameter D
Is changed from “4” to “7”, the interleave length becomes about 7/4 times, which is a double density CD-R.
This value has been empirically obtained as an optimal value when the interleave processing is performed on the data to be recorded in the data.
That is, when the delay parameter is set to “7” and the data to be recorded on the double-density CD-R is subjected to the interleave processing, the delay parameter is set to “4” and 1
The same ability to correct burst errors as in the case of performing interleave processing on data recorded on a double-density CD-R could be secured. When the delay parameter D is smaller than "7", the correction capability for the burst error is insufficient. On the other hand, if the delay parameter D is too large, a large-capacity memory is required, which is problematic in terms of cost. Therefore, in performing the interleaving process on the data to be recorded on the double-density CD-R, the delay parameter D is set to “7”.

On the other hand, in the data reproducing system 22, the CD
A signal recorded as a recording mark sequence on R100 is read out by the optical pickup 32,
Supplied to The reproduction amplifier 33 includes the optical pickup 3
2 based on the signal (photoelectrically converted voltage signal)
It generates a reproduction signal (RF signal), a focus error signal, a tracking error signal, a wobble signal, and the like.

The reproduction signal generated by the reproduction amplifier 33 is
The data is converted into digital data via a binarization circuit, a clock extraction circuit, and the like (not shown), and supplied to the EFM demodulation circuit 34. The focus error signal and the tracking error signal generated by the reproduction amplifier 33 are supplied to a servo control unit (not shown). The servo controller performs focus servo and tracking servo in the optical pickup 32 based on the focus error signal and the tracking error signal.

The wobble signal from the reproduction amplifier 33 is supplied to the ATIP decoder 35. Here, the wobble signal is a signal obtained from the pre-groove of the CD-R 100. In the CD-R, as described above, the FM-modulated position information, that is, the time axis information indicating the absolute position on the disk is recorded by the wobbling of the pre-groove. This information is called ATIP (Absolute Time In Pregroove) information, and in an optical disc such as a CD-R or CD-RW, a wobble signal is decoded by an ATIP decoder 35 to obtain this ATIP information, so that unrecorded information is obtained. Even in the state, the absolute position on the disk can be detected.

The digital data (reproduced data) supplied to the EFM demodulation circuit 34 is subjected to EFM demodulation by the EFM demodulation circuit 34,
Supplied to In addition, the EFM demodulation circuit 34 expands a subcode included in the reproduction data and supplies the subcode to a control unit 43 described later.

The CIRC decoder 36 is the C1 decoder 3
7, a first deinterleaver 38 and a second deinterleaver 39, a switch circuit 40 for switching between the first deinterleaver 38 and the second deinterleaver 39, and a C2 decoder 41. It has.

The reproduced data from the EFM demodulation circuit 34 is
First, it is supplied to the C1 decoder 37. C1 decoder 3
Numeral 7 performs error correction by C1 code on the supplied reproduced data. By the error correction using the C1 code,
Random errors, which are mainly small errors, will be corrected. The reproduced data on which the error correction by the C1 code has been performed by the C1 decoder 37 is supplied to one of the first deinterleaver 38 and the second deinterleaver 39 selected by the switch circuit 40. .

The first deinterleaver 38 has a delay parameter D set to “4” and corresponds to the first interleaver 26 of the CIRC encoder 24. That is, the first deinterleaver 38
Interleave processing is performed by the first interleaver 26 and recorded on a single-density CD-R.
A deinterleave process is performed on the reproduction data read from the DR.

On the other hand, the second deinterleaver 39 has the delay parameter D set to “7” and corresponds to the second interleaver 27 of the CIRC encoder 24. That is, the second deinterleaver 3
No. 9 is recorded in a double-density CD-R after being subjected to an interleaving process by the second interleaver 27, and a de-interleaving process is performed on reproduction data read from the double-density CD-R. It has been done.

The reproduced data deinterleaved by the first deinterleaver 38 or the second deinterleaver 39 is supplied to the C2 decoder 41.
The C2 decoder 41 performs error correction using C2 code on the reproduction data on which the deinterleaving process has been performed. By the error correction using the C2 code, a burst error, which is a large error, is mainly corrected. The reproduced data on which the C2 decoder 41 has performed the error correction using the C2 code is output from an output terminal 42 and supplied to a host computer or the like.

In the data reproducing system 22 of the optical disk device 20, as described above, the two interleavers 26 and 27
, Two deinterleavers 38 and 39 are provided. In the optical disc device 20, the delay parameter D is set by the first interleaver 26.
When the data recorded on the single-density CD-R is reproduced by performing the interleave processing with “4”, the first deinterleaver 38 is selected by the switch circuit 40 and the first deinterleaver 38 is selected. The deinterleaver 38 performs a deinterleave process. In the optical disk device 20, when the second interleaver 27 performs an interleaving process in which the delay parameter D is "7" and reproduces data recorded on a double-density CD-R, the switch The circuit 40 selects the second deinterleaver 39, and the second deinterleaver 29 performs a deinterleave process.

As described above, the optical disk device 20
Switching between an interleaver and a de-interleaver for recording and reproducing data on a double-density CD-R and for recording and reproducing data on a double-density CD-R, respectively. , Appropriate interleave processing and deinterleave processing are performed. Therefore, according to the optical disk device 20,
While performing a proper recording / reproducing operation while suppressing a decrease in correction capability for a burst error which is a concern in a double-density CD-R having an increased recording density, it is also applicable to a single-density CD-R as before. Recording and reproducing operations can be performed.

In this optical disk device 20,
The operation of each unit is controlled by the control unit 43. For example, a single-density CD-R and a double-density CD-R are driven to rotate at a predetermined speed by a spindle motor (not shown).
For example, when performing a recording / reproducing operation on a single-density CD-R, the spindle motor converts the single-density CD-R into a CLV having a linear velocity of 1.2 m / sec.
(Constant Linear Velocity: constant linear velocity), when performing a recording / reproducing operation on a double-density CD-R, the spindle motor converts the double-density CD-R into a linear velocity of 0.9 m / It is designed to be driven to rotate at CLV for sec.

The operation of the optical pickup 32 is also controlled by the control unit 43. For example, the above-described focus servo and tracking servo are also performed under the control of the control unit 43, and the control of laser power and the like is also performed. This is performed by the control unit 43. Further, an access operation for causing the optical pickup 32 to access a predetermined recording track is also performed under the control of the control unit 43. Here, the access operation of the optical pickup 32 is performed by, for example, the control unit 43 based on ATIP information and the like obtained by decoding the above-described wobble signal in the ATIP decoder 35.
Is appropriately controlled by controlling a thread motor or the like.

The switching of the switch circuit 28 of the CIRC encoder 24 and the CIRC decoder 36
Of the switch circuit 40 is also controlled by the control unit 43. Specifically, for example, at the time of reproduction, the control unit 43 controls the CD-R 100 that reproduces data based on the error correction information included in the subcode supplied from the EFM demodulation circuit 34 in a single-density CD-R. Is determined to be a double-density CD-R.
The switching of the switch circuit 40 of the C decoder 36 is performed. Further, when recording is performed on a double-density CD-R, the control unit 43 corresponds to the switch circuit 28 and the CI
The switch circuit 40 of the RC decoder 36 is switched, and the EFM modulation circuit 30 is controlled to add a subcode including error correction information according to the unit delay amount selected by the switch circuit 40.

[0073]

As described above, in the optical recording medium according to the present invention, the error correction information is recorded in the subcode. It is easy to determine whether to perform error correction using such a CIRC format. Therefore, for example, even in the case of increasing the recording density in order to realize a large capacity, it is possible to select and record the optimal CIRC format capable of sufficiently correcting errors, It is possible to reliably determine the CIRC format applied to the recording medium, correct an error, and perform quick and reliable reproduction.

In the information recording apparatus according to the present invention, when recording on an optical recording medium, the CIR
Error correction information on the C format can be recorded. Therefore, when reproducing the optical recording medium, it is possible to easily determine what CIRC format is applied. Therefore, it is possible to select and record an optimal CIRC format capable of sufficiently correcting an error according to the increase in recording density, and to ensure that the applied CIRC format is reproduced when reproducing the optical recording medium. , The error can be corrected, and the reproduction can be performed quickly and reliably.

Further, the information reproducing apparatus according to the present invention, when reproducing the information signal recorded on the optical recording medium, corrects the error of the main data based on the error correction information recorded in the subcode. It can be carried out. Therefore, even when each optical recording medium is recorded in a different CIRC format, it is possible to appropriately select a CIRC format suitable for the optical recording medium and quickly and surely reproduce the information. That is, the optimum CI that can sufficiently correct the error according to the increase in the recording density
The optical recording medium to which the RC format is applied can be reliably reproduced.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a CD-R shown as an example of an optical recording medium to which the present invention has been applied.

FIG. 2 is a schematic sectional view showing a laminated structure of the CD-R.

FIG. 3 is an enlarged schematic view of a main part showing a pre-groove formed on the CD-R.

FIG. 4 is a schematic view showing a recording area in the CD-R.

FIG. 5 is a schematic diagram showing a configuration of one frame as a data transmission unit in the CD-R.

FIG. 6 is a schematic diagram showing a configuration of one data block as a basic unit forming a subcode in the CD-R.

FIG. 7 is a schematic diagram showing a configuration of main data included in a data block in the CD-R.

FIG. 8 is a schematic diagram showing a configuration of a subcode in the CD-R.

FIG. 9 is a block diagram of an optical disk device shown as an example of an information recording device and an information reproducing device to which the present invention has been applied.

FIG. 10 is a diagram for describing an error correction process by CIRC.

[Explanation of symbols]

1 disk substrate, 2 signal recording layer, 3 reflection layer, 4
Protective layer, 11 PCA, 12 PMA, 13 lead-in area, 14 logical tracks, 15 lead-out area, 16 program area, 20 optical disk device,
24 CIRC encoder, 26 first interleaver, 27 second interleaver, 36 CIRC decoder, 38 first deinterleaver, 39 second deinterleaver

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) G11B 20/18 572 G11B 20/18 572F (72) Inventor Tatsuro Mikami 6-7-35 Kitashinagawa, Shinagawa-ku, Tokyo Sony Corporation F term (reference) 5D044 BC05 BC06 CC04 DE37 DE53 DE68 DE84 DE86 GK11 5D090 AA01 BB03 BB04 CC01 DD03 DD05 FF43 GG11 GG29 GG32 GG33 HH03

Claims (6)

[Claims] 1. A disk-shaped optical recording medium on which information signals are recorded and / or reproduced along recording tracks, wherein the recording tracks are subjected to an error correction process including an interleaving process for the information signals to be recorded. Optical recording characterized in that the main data and the subcode including access information to the main data are recorded, and error correction information relating to the error correction processing is recorded in the subcode. Medium. 2. The optical recording medium according to claim 1, wherein the error correction information includes information indicating a unit delay amount in the interleaving process. 3. The optical recording medium according to claim 1, wherein the error correction information is recorded in the sub-code in a lead-in area including TOC information. 4. The optical recording medium according to claim 1, wherein the error correction information is recorded on a Q channel in the subcode. 5. An information recording apparatus for recording an information signal along a recording track on a disc-shaped optical recording medium, comprising: main data obtained by performing an error correction process including an interleave process on the information signal to be recorded; Signal processing means for generating access information for the main data, and a subcode including error correction information relating to the error correction processing; rotation driving means for rotating the optical recording medium at a predetermined speed; An information recording apparatus, comprising: recording means which is movable in a radial direction of a medium and records the main data and the subcode on the optical recording medium. 6. An information reproducing apparatus for reproducing an information signal recorded along a recording track on a disk-shaped optical recording medium, comprising: a rotation driving means for driving the optical recording medium to rotate at a predetermined speed; Detecting means for being movable in the radial direction of the optical recording medium and detecting an information signal recorded on a recording track of the optical recording medium; and interleaving processing from the information signal detected by the detecting means. The main data subjected to the error correction processing and the sub-code including the access information for the main data are developed, and the error correction of the main data is performed based on the error correction information regarding the error correction processing included in the sub-code. And a signal processing means for performing the following.