JPH09190679A - Information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the decrease of the actual recording capacity of a user recording area by constituting this medium in such a manner that the substitutive recording of the information to the substitutive area for a partial defect area is executed when this area is judged to be a defect area. SOLUTION: The optical disk 1 is recorded with defect management information on the innermost periphery of a recording film 1a and is composed of the substitutive area. The management information area C is so formed as to be recorded with the new and old defect management information (error management information) of every 4K byte. Namely, the defect management information updated with the defect substitutive area information at the time of recording is recorded therein. Two pieces of the same information are written therein, thereby, the reliability of the defect management information is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium such as an optical disc on which information is recorded or reproduced.

[0002]

2. Description of the Related Art In recent years, a large amount of image information of a document or the like is photoelectrically converted by two-dimensional optical scanning, and this photoelectrically converted image information is recorded in an image recording device, or if necessary. 2. Description of the Related Art Recently, an optical disc has been used as an image recording device in an image information file device capable of searching and reproducing and reproducing and outputting as a hard copy or a soft copy.

Conventionally, in such an optical disk apparatus, an optical disk for recording information in a spiral shape is used, and information is recorded or reproduced by an optical head which is linearly moved by a linear motor in the radial direction of the optical disk. It is like this.

In such an optical disc, the defective area (block) is determined by reading the pre-header at the time of manufacture, and the data is recorded on the disc. As a result, recording is performed while skipping the defective area. Also, when recording is performed, if read-after-write is performed and reading is not possible even if correction is performed, the area (block) that cannot be read is determined to be a defective area, and another block is set as a substitute block. Recording information for the defective area is recorded in the block. Then, the defect area is recorded in the defect management area.

However, in the above-mentioned optical disk,
Recording is not performed on a defective area at the time of manufacturing, and recording is performed again on another defective area at the time of recording in another area managed by the host computer. Therefore, the actual recording capacity of the user recording area has been reduced.

Further, since the alternative area is not fixed and managed by each host computer, there is no compatibility for each disk.

[0007]

As described above, the disadvantage that the actual recording capacity of the user recording area is reduced is eliminated, and it is used without reducing the actual recording capacity of the user recording area. It is an object of the present invention to provide an information recording medium capable of maintaining compatibility with an alternative area for managing the alternative processing for the defective area.

[0008]

The information recording medium of the present invention, in which defect management information indicating an alternative area to a defective area is stored, is a user record used for recording or reproducing information by a user. area,
There is a replacement area corresponding to the partial defect area in the user recording area, and a management area for storing defect management information indicating the replacement area corresponding to the partial defect area in the user recording area. When the partial area to be recorded in the user recording area is determined to be a defective area by the defect management information of the management area, alternative recording of information to the alternative area corresponding to the partial defective area is performed. After the recording of the information, the recorded information is read from the user recording area and the information is reproduced by performing the error correction. When the reproduction of the information is not performed correctly, the user recording is performed. Using a partial area in the area as a defective area, alternative recording of information to the alternative area is performed and Correspondence between the defective area and the alternative area is stored in the management area as defect management information, and when reproducing information, the area to be reproduced in the user recording area is a defect area according to the defect management information of the management area. If it is determined that the information is reproduced in the alternative area corresponding to the partially defective area.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a schematic structure of an optical disk device in which the disk of the present invention is used. That is, the optical disk (disk) 1 has a spiral or concentric information storage unit having a constant radial pitch and is rotationally driven by the motor 4.

[0011] As shown in FIG.
For example, a metal film layer of tellurium, bismuth or the like, that is, a recording film 1a is coated in a donut shape on the surface of a substrate formed of glass or plastics in a circular shape, and a cutout part is formed near the center of the metal film layer. A reference position mark 1 ₁ is provided.

Further, as shown in FIG. 4, on the optical disc 1, the reference position mark _{11 is set} to "0" and "0 to 25".
5 "into 256 sectors. Variable length information is recorded on a plurality of blocks on the optical disc 1, and 36000 is recorded on the optical disc 1.
300,000 blocks are formed on the track.

The number of sectors of one block on the optical disc 1 is, for example, 40 sectors inside and 20 sectors outside. At the start position of the block, a block header A including a block number, a track number, and the like is recorded, for example, when the optical disc 1 is manufactured. When each block on the optical disc 1 does not end at the sector switching position, a block gap is provided so that each block always starts from the sector switching position.

As shown in FIGS. 5 and 6, the optical disc 1 has defect management information recorded on the innermost circumference of the recording film 1a and is composed of an alternative area, for example, an alternative process for 1000 tracks. A recording area (alternate processing recording area) a is provided, and in addition to this, a user area (user recording area) b as a recording area used by the user is provided.

As shown in FIG. 7, the substitute processing area a is a management information area (correct) c in which new and old defect management information f of 4 Kbytes is recorded, and this management information area c.
It is composed of a management information area (sub) d in which the same information is recorded and an alternative block area e in which an alternative block (alternative area) is prepared. The substitute block is a block used as a substitute for a defective block (defective area) in the user area b during manufacturing or recording.

In the management information area c (, d), as shown in FIG. 7, new and old defect management information (error management information) f is recorded every 4 Kbytes.
That is, the defect management information in which the defect replacement area information at the time of recording is updated is recorded. Here, two pieces of the same information are written to improve the reliability of the defect management information.

As shown in FIG. 8, the defect management information f includes initial defect replacement area information g and recording defect replacement area information h. The initial defect replacement area information g is information for designating a replacement block (substitution area) for a defect at the time of manufacture, that is, a block (defect area) that cannot be recorded at the time of manufacture. For example, a pre-header is read. ., A substitute block number (substitute area) for a block number (defective area) in which the pre-header cannot be read.

The above-mentioned defect replacement area information at the time of recording h designates a defect found at the time of recording, that is, a replacement block (replacement area) for a block (defect area) where recording cannot be performed correctly at the time of recording. This is information. For example, the recorded information is played back (after read-after-write), and it is judged whether or not it was correctly written by whether it was played correctly. Block number (alternative area)
Is stored. That is, it is information for designating writing to another area for an area that cannot be understood unless it is actually written.

1 and 2 below the optical disk 1.
As shown in FIG. 3, an optical head 5 for recording and reproducing information is provided. The optical head 5 includes a movable portion 6 and a fixed portion 8 of the direct current linear motor 3 which is a movable portion 6.
Is fixed to the optical disk 1 by the movement of the movable part 6.
Is linearly moved in the radial direction, that is, in the directions a and b in the figure. 9 is a detector for detecting the position of the movable part 6,
These are movable parts 6 by a so-called superimposed grid detection method.
That is, two types of detection signals having different phases (the phase relationship changes depending on the direction) are output according to the movement amount of the optical head 5.

On the other hand, the optical head 5 fixed to the linear motor 3 includes a semiconductor laser, a collimator lens, a beam splitter, an objective lens, a focus drive coil for driving the objective lens in the direction of the optical disc 1, and an objective lens having a radius of the optical disc 1. Tracking drive coil for driving in the direction, a focus detector having a pair of photodetectors for detecting whether or not the laser beam light is focused on the optical disc 1, and a pair of photodetectors for detecting whether or not tracking is performed on the information track. A tracking detector having.

A detection signal is output from each photodetector to a corresponding processing circuit, and a predetermined voltage is applied to each drive coil and semiconductor laser from each drive circuit.

The control circuit 20 controls the entire device according to a signal from an external device, that is, a host computer (not shown). The linear motor drive circuit 14 uses the target position signal and the detector 9 supplied from the control circuit 20.
The linear motor 3 is driven according to the output signal of.

On the other hand, the rotary motor drive circuit 10
The speed is determined according to the rotation clock from the control circuit 20, and the speed is controlled to the speed set by the control circuit 20. The focus servo circuit 11 adjusts the focus of the objective lens in the optical head 5 according to the detection signal from the detector in the optical head 5, and the focus pull-in circuit 1
6 makes it possible to accurately perform focusing when changing from a state in which focusing is not working to a state in which it is working.

The tracking servo circuit 12 sets the objective lens of the optical disk 1 so that the light beam emitted through the objective lens in the optical head 5 is at the center of the track in accordance with the detection signal from the detector in the optical head 5. It can be moved in the radial direction. Further, the tracking servo circuit 12 can temporarily stop the servo operation and generate a track jump drive pulse in accordance with the track jump pulse from the track jump pulse generation circuit 17 to move the objective lens and move the beam light for one track. It is possible.

The pit signal waveform shaping circuit 13 shapes the waveform of the detection signal from the detector in the optical head 5. The binarization circuit 18 binarizes the waveform shaping signal from the pit signal waveform shaping circuit 13.

The reference clock generator 41 generates a reference clock. The variable clock generation circuit 19
The reference clock supplied from the reference clock generator 41 is a clock signal (reference signal) having a frequency (time width) according to the clock speed information supplied from the control circuit 20.
Is to occur. That is, as the position of the optical head 5 moves outward of the optical disk 1, the frequency of the clock signal becomes higher (the time width becomes shorter).

The reproduction synchronous clock extraction circuit 23
When a control signal from the control circuit 20 is supplied,
According to the clock signal supplied from the variable clock generation circuit 19, the reproduction synchronous clock recorded first in the block header A of each block is extracted from the data supplied from the binarization circuit 18. .

The demodulation circuit 22 responds to the clock signal from the variable clock generation circuit 19 by following the reproduction synchronization clock from the reproduction synchronization clock extraction circuit 23.
The data supplied from the digitization circuit 18 is demodulated. The serial-parallel conversion circuit 25 converts the reproduction signal supplied from the demodulation circuit 22 from serial data into parallel data according to the clock signal from the variable clock generation circuit 19.

The header discriminating circuit 26 comprises the demodulating circuit 22
The reproduction signal supplied from the variable clock generation circuit 1
Only the header data is discriminated according to the clock signal from 9. The recording / reproducing header register 29 stores the accessed header data supplied from the control circuit 20.

The header comparator 28 compares the header data stored in the recording / reproducing header register 29 with the header data supplied from the header discriminating circuit 26, and outputs a coincidence signal when they match. It is a thing.

The parallel-serial conversion circuit 24
Is for converting a reproduction signal supplied from a recording / reproducing switching circuit 27, which will be described later, from parallel data to serial data in accordance with a clock signal from the variable clock generating circuit 19.

The modulation circuit 21 modulates the data supplied from the parallel-serial conversion circuit 24 according to the clock signal from the variable clock generation circuit 19. The laser drive circuit 15 records data by drivingly controlling a semiconductor laser (not shown) in the optical head 5 according to the modulation signal supplied from the modulation circuit 21.

The recording / reproducing switching circuit 27 records the reproduction data following the header data when the coincidence signal is supplied from the header comparator 28 in response to the reproduction control signal from the control circuit 20, that is, the recording / reproducing data buffer 30. Is output to.

The recording / reproducing switching circuit 27
Is for outputting recording data following the header data supplied from the recording / reproducing data buffer 30 to the parallel / serial conversion circuit 24 in response to a recording control signal from the control circuit 20.

The recording / reproducing data buffer 30 stores the reproducing data from the recording / reproducing switching circuit 27 and the recording data from the recording / reproducing data transfer circuit 32. The error correction code adding / error correcting circuit 31 adds an error correction code by the Reed-Solomon method to the recording data stored in the recording / reproducing data buffer 30 and also reproduces the reproducing data stored in the recording / reproducing data buffer 30. The error is corrected.

The above-mentioned error correction code addition / error correction circuit 3
In No. 1, in the case of read-after-write at the time of recording, the weak correction capability is used for correction to perform a strict check, and at the time of reproduction, the normal error correction capability is used for correction.

The weak correction capability is the size of the error that can be corrected, which is smaller than that during normal reproduction. Since the correction method using the cross interleave in the error correction code addition / error correction circuit 31 is described in detail in Japanese Patent Application No. 59-15501, it will be omitted here.

The recording / reproducing data transfer circuit 32 transfers the reproducing data supplied from the recording / reproducing data buffer 30 to the host computer (not shown) via the external interface circuit 33, and the host computer external interface circuit. The recording data supplied via 33 is output to the recording / reproducing data buffer 30.

Further, as shown in FIG. 9, the ROM 42 as a storage circuit has clock speed information of the optical disc 1 for every 256 tracks, the number of sectors of one block at this clock speed, and the first of 256 tracks at the above speed. A conversion table in which the block number and the start sector of the block correspond to each other is stored.

Further, when the control circuit 20 is supplied from the host computer via the external interface circuit 33 with the block number of the recording or reproducing position, that is, the position to be accessed, the control circuit 20 accesses according to the block number. The position is read from the ROM 42, and the linear motor 3 and the optical head 5 access the position while keeping the frequency of the clock signal constant. Since the clock speed information and the reading (calculation) of the access position are described in detail in Japanese Patent Application No. 59-32825, they are omitted here.

Further, the control circuit 20 stores the latest defect management information read from the management information area c (, d) of the optical disc 1 in the memory buffer 43 when the optical disc 1 is set in the apparatus (when it is opened). Also, when the optical disc 1 is removed from the apparatus (when closed) or when the defect management information is updated, the defect management information stored in the memory buffer 43 is used as the latest information to manage the optical disc 1 in the management information area c. , D in the first unrecorded area.

The memory buffer 43 has a capacity of an integral multiple of the minimum recording unit of data, for example, 4K which is the same as one block.
As shown in FIG. 10, the bytes are used to store initial defect replacement area information as defect management information and recording defect replacement area information.

Next, the operation of the above structure will be described. First, the optical disc 1 is set in this device (at the time of opening). Then, the control circuit 20 firstly sets the motor 4
To rotate the optical disk 1 at a constant speed. Then, the control circuit 20 reads the clock speed information and the access position, that is, the track number and the start sector number according to the block number corresponding to the management information area c from the ROM 42.

As a result, the control circuit 20 outputs the clock speed information to the variable clock generation circuit 19. Then, the variable clock generation circuit 19 causes the reference clock generator 4 to
A clock signal having a frequency (time width) according to the clock speed information supplied from the control circuit 20 is generated using the reference clock from No. 1, and the modulation circuit 21, the demodulation circuit 22, the reproduction synchronous clock extraction circuit 23, the parallel circuit -Supply to the serial conversion circuit 24, the serial-parallel conversion circuit 25, and the header discrimination circuit 26.

Further, according to the track number, the control circuit 20 converts the track number into a scale value, and drives the linear motor driver 14 until the scale value and the position detected by the output of the position detector 9 match. By doing so, the optical head 5 is moved. Then, when the movement of the optical head 5 is completed, the detection signal from the detector in the optical head 5 is shaped by the waveform shaping circuit 13,
It is binarized by the binarization circuit 18 and supplied to the demodulation circuit 22 and the reproduction synchronous clock extraction circuit 23. Then, the reproduction synchronization clock extraction circuit 23 extracts the reproduction synchronization clock recorded first in the block header A from the supplied data and outputs it to the demodulation circuit 22.

As a result, the demodulation circuit 22 demodulates the reproduction synchronization clock and the read signal subsequently supplied from the binarization circuit 18, and the read signal is sent to the recording / reproduction switching circuit 27 via the serial-parallel conversion circuit 25. It outputs and supplies to the header discrimination circuit 26. The header discriminating circuit 26 discriminates only the header data to discriminate the control circuit 20.
And to the header comparator 28.

As a result, the control circuit 20 determines the track to which the optical head 5 corresponds from the header data,
Compare this track with the target track. As a result of this comparison, the control circuit 20 moves the optical head 5 again by the linear motor 3 when it is separated by several tens of tracks or more, and when it is within several tens of tracks, the optical head 5 is moved by the number of corresponding tracks by the track jump. Moving.

When the optical head 5 corresponds to the target track, the header discriminating circuit 26 discriminates only the header data and outputs it to the header comparator 28. At this time,
The header data of the target block, that is, the block corresponding to the management information area c is stored in the header register 29 in advance by the control circuit 20, and the header data of the header register 29 is supplied to the header comparator 28. Thus, the header comparator 28 outputs a match signal to the recording / reproducing switching circuit 27 when the header data match. Then, the recording / reproduction switching circuit 27 outputs the reproduction data supplied following the header data to the recording / reproduction data buffer 30.

The reproduction data of the recording / reproduction data buffer 30 is error-corrected by the error correction code addition / error correction circuit 31 and then supplied to the control circuit 20. As a result, the defect management information f for every 4 k bytes in the management information areas c and d is sequentially supplied to the control circuit 20.

Then, the control circuit 20 reads the latest defect management information f from the management information areas c and d and stores it in the memory buffer 43. In reading the latest defect management information f, the defect management information f in front of five consecutive free areas is read as the latest information. The reliability of data is confirmed by comparing the latest defect management information f read from the management information areas c and d.

Next, in the state where the latest defect management information is stored in the memory buffer 43 as described above, the block number for recording (accessing) from the host computer (not shown) via the external interface circuit 33. Is supplied to the control circuit 20. Then
The control circuit 20 indicates that the block number is the memory buffer 4
It is checked whether it is included in the initial defect replacement area information g of No. 3, that is, whether it is the initial defect area. As a result of this check, if the area is not the initial defect area, the block is recorded as a block number from the host computer. Further, as a result of the above check, in the case of the initial defect area, the replacement block read by the initial defect replacement area information g is set as a block for recording.

Then, the control circuit 20 uses the conversion table of the ROM 42 to calculate the track, start sector and clock speed information of the target block (block number from the host computer or alternative block). Then, the control circuit 20 outputs the clock speed information to the variable clock generation circuit 19. As a result, the variable clock generation circuit 19 uses the reference clock from the reference clock generator 41 to generate a clock signal having a frequency according to the clock speed information supplied from the control circuit 20, and the modulation circuit 21 and the demodulation circuit 22. , The reproduction synchronization clock extraction circuit 23, the parallel-serial conversion circuit 24, the serial-parallel conversion circuit 25, and the header discrimination circuit 26.

Further, according to the track number, the control circuit 20 operates in the same manner as in the case of accessing the above-mentioned alternative processing area, and makes the light beam of the optical head 5 correspond to the track of the target block.

At this time, the recording data is recorded / reproduced from the host computer via the external interface circuit 33 and the recording / reproduction data transfer circuit 32.
Is stored in

When the match signal of the block header of the target block is supplied from the header comparator 28 to the recording / reproducing switching circuit 27, the recording data in the recording / reproducing data buffer 30 is parallel-serial by the recording / reproducing switching circuit 27. It is supplied to the conversion circuit 24. The recording data converted into serial data by the parallel-serial conversion circuit 24 is subjected to MFM modulation by the modulation circuit 21 and supplied to the laser drive circuit 15. This allows
The laser drive circuit 15 records data by driving a semiconductor laser (not shown) in the optical head 5 according to the supplied modulation signal.

After this recording, read-after-write is performed.
That is, the block on which the recording has been performed is read. That is, the control circuit 20 causes the laser beam of the optical head 5 to correspond to the track of the target block, as in the case of the above recording.

When the match signal of the block header of the target block is supplied from the header comparator 28 to the recording / reproducing switching circuit 27, the recording / reproducing switching circuit 27 records the reproduced data from the serial-parallel conversion circuit 25. It is supplied to the reproduction data buffer 30. The reproduction data stored in the recording / reproduction data buffer 30 is subjected to error correction by the weak correction capability in the error correction code addition / error correction circuit 31. As a result, if no correction error (defect) occurs, the control circuit 20 ends the recording process.

Further, as a result of the above, when a correction error (defect) occurs, the control circuit 20 determines the alternative block to be used next based on the defect alternative area information at the time of recording, and rewrites the recording data in the alternative block. After this recording is performed, if read-after-write is performed in the same manner as described above, and if no correction error (defect) occurs, the control circuit 20 uses the substitute block corresponding to the defective block to record defective substitute area information in the memory buffer 43. Is updated and the information in the memory buffer 43 is recorded in the management information areas c and d. When a correction error (defect) occurs, the control circuit 20 re-records the recording data in another alternative block, and thereafter operates in the same manner as above.

Also, when data is recorded in another block, it can be performed in the same manner as described above. In this case, data recording is performed in a state where the frequency of the clock signal is increased as the block position is located on the outer peripheral side.

The operation during recording is as shown in FIG.

A host computer (not shown)
It is assumed that a block number for reproduction (access) is supplied from the external interface circuit 33 to the control circuit 20.

Then, the control circuit 20 checks whether the block number is included in the initial defect replacement area information g of the memory buffer 43, that is, whether it is the initial defect area. If the result of this check is that the block is not an initial defect area, the block number from the host computer is set as a block to be reproduced. Further, as a result of the above check, in the case of the initial defect area, the replacement block read by the initial defect replacement area information g is set as the block to be reproduced.

Then, as in the case of the above-mentioned recording, the clock speed information corresponding to the block (the block number from the host computer or the alternative block) is read, and the clock signal of the frequency corresponding to the clock speed information is modulated. The signal is supplied to the circuit 21, the demodulation circuit 22, the reproduction synchronous clock extraction circuit 23, the parallel-serial conversion circuit 24, the serial-parallel conversion circuit 25, and the header discrimination circuit 26.

Further, as in the case of the above recording, the laser beam of the optical head 5 is made to correspond to the track of the target block.

When the match signal of the block header of the target block is supplied from the header comparator 28 to the recording / reproducing switching circuit 27, the recording / reproducing switching circuit 27 records the reproduced data from the serial-parallel conversion circuit 25. It is supplied to the reproduction data buffer 30. The reproduction data stored in the recording / reproduction data buffer 30 is error-corrected by an error correction code addition / error correction circuit 31 with a normal error correction capability. As a result, if no correction error (defect) occurs, the control circuit 20 transfers the reproduction data to the host computer via the recording / reproduction data transfer circuit 33 and the external interface circuit 33, and ends the reproduction processing.

Further, as a result of the above, when a correction error (defect) occurs, the control circuit 20 reads the replacement block corresponding to the defective block from the recording defect replacement area information in the memory buffer 43, and records the replacement block. The data is corrected and reproduced with the ordinary error correction capability in the same manner as above. Then, the control circuit 20 transfers the reproduction data from the alternative block to the host computer via the recording / reproduction data transfer circuit 33 and the external interface circuit 33, and ends the reproduction processing.

Also, when the data of another block is reproduced, the same operation as described above can be performed. In this case, data is reproduced in a state where the frequency of the clock signal is increased as the block position is located on the outer peripheral side.

The operation during the reproduction is as shown in FIG.

When the optical disk 1 is removed (closed) or when the defect management information is updated, the control circuit 20 uses the defect management information stored in the memory buffer 43 as the latest information. The data is recorded in the first unrecorded area of the areas c and d.

As described above, in the optical disc in which the defect management information indicating the alternative area to the defective area is stored, the user recording area used for recording or reproducing the information by the user, and a partial area in this user recording area. It has an alternative area corresponding to the defective area and a management area for storing defect management information indicating the alternative area corresponding to the partial defective area in the user recording area.

As a result, the user area can be used without reducing the actual recording capacity, and since the positions of the management information area and the alternative block area are fixed on the optical disk, they are compatible with each other. There is a nature.

In the above embodiment, the case where the optical disk is used as the information recording medium has been described, but the present invention is not limited to this, and a magnetic disk, a floppy disk, a laser card, etc. may be used.

[0073]

As described in detail above, according to the present invention,
It is possible to use without reducing the actual recording capacity of the user recording area, and it is possible to provide an information recording medium compatible with defect management.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a configuration of an optical disc device of the present invention.

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

FIG. 3 is a plan view showing the configuration of an optical disc.

FIG. 4 is a plan view showing the configuration of an optical disc.

FIG. 5 is a plan view for explaining an alternative processing area and a user area.

FIG. 6 is a plan view for explaining a configuration of an alternative processing area.

FIG. 7 is a diagram showing a recording example of a management information area.

FIG. 8 is a diagram for explaining an example of recording defect management information.

FIG. 9 is a diagram showing an example of storage of a conversion table.

FIG. 10 is a diagram for explaining a storage example of a memory buffer.

FIG. 11 is a flowchart for explaining a recording operation.

FIG. 12 is a flowchart for explaining a reproduction operation.

[Explanation of symbols]

 1 ... Optical disc (information recording medium) 1a ... Recording film a ... Alternate processing area (alternate processing recording area) b ... User area (user recording area) c, d ... Management information area e ... Alternate block area f ... Defect Management information g ... Initial defect replacement area information h ... Recording defect replacement area information

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G11B 20/18 572 9558-5D G11B 20/18 572C 9558-5D 572F

Claims (1)

[Claims] 1. An information recording medium in which defect management information indicating an alternative area to a defective area is stored, a user recording area used for recording or reproducing information by a user, and a partial area of the user recording area. And a management area for storing defect management information indicating the replacement area corresponding to the partial defect area in the user recording area. When the information is recorded, in the user recording area If the partial area to be recorded is determined to be a defective area by the defect management information of the management area, alternative recording of information to the alternative area corresponding to this partial defective area is performed, and After recording, the recorded information is read from the user recording area, and the information is corrected by error correction. When the reproduction is performed and the reproduction of this information is not performed correctly, the partial recording in the alternative area is performed while the partial recording in the user recording area is used as the defective area, and the partial defective area is also recorded. The correspondence between the replacement area and the alternative area is stored in the management area as defect management information, and when reproducing the information, the area to be reproduced in the user recording area is determined to be a defect area based on the defect management information of the management area. The information recording medium is characterized in that the information is reproduced to the alternative area corresponding to the partially defective area when the information is reproduced.