JPS6358670A - Information recording medium - Google Patents

Abstract

PURPOSE:To use a user memory area with no reduction of its memory capacity by recording the record information and the defect control information to be applied to a defective area of a user recording area into a substitute area and a substitute processing recording area. CONSTITUTION:The surface of a substrate of an optical disk is coated with a recording film 1a. The defect control information is recorded to the most inner circumference of the film 1a and at the same time a substitute processing area (a) is provided together with a user area (b) serving as a recording area for users. The area (a) includes a control information area (original) c, a control information area (duplicate) d, and a substitute block area (e) where a substitute area is prepared. The substitute block is used to a defective block in the area (b) at the time of producing or recording. Thus it is possible to use the area (b) with no reduction of its actual memory capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to an information recording medium such as an optical disc on which information is recorded or reproduced.

(Prior art) In recent years, uniform information such as sentence 1, which is generated in large quantities, is photoelectrically converted by two-dimensional optical scanning, and this photoelectrically converted image information is recorded on an image recording device, or it is used as needed. Recently, optical disks have been used as image recording devices in image information file devices that can reproduce and output images as hard copies or soft copies.

Conventionally, such optical disk devices use an optical disk that records information in a spiral manner, and information is recorded or reproduced using an optical head that moves linearly in the radial direction of the optical disk using a linear motor. It has become.

In such optical discs, defective areas (blocks) are determined by reading the header during manufacture, and the data is recorded on the disc. As a result, recording is performed while skipping the defective area. Also, when recording, if reading cannot be performed even after performing read after write 1- and making corrections,
The area (block) that cannot be read is determined to be a defective area, another block is used as a substitute block, and information recorded in the defective area is recorded in this substitute block. The defect area is then recorded in the defect management area.

However, with the above-mentioned optical discs, recording is not performed on defective areas at the time of manufacture, and recording is performed again on defective areas during recording in another area managed by the host computer. . As a result, the actual recording capacity of the user recording area has been reduced.

Furthermore, since the alternative area was not fixed and was managed by each host 1 to computer, there was no compatibility between disks.

(Problem to be Solved by the Invention) This eliminates the drawback that the actual recording capacity of the user recording area is reduced as described above, and it can be 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 that can maintain compatibility with respect to alternative areas for managing alternative processing for defective areas.

[Structure 1 of the Invention (Means for Solving Problems) The information recording medium of the present invention includes a user recording area used by a user, and an alternative area for alternatively recording information recorded in a defective area in this user recording area. has
and an alternative processing recording area that stores defect management information indicating an alternative area for the defective area in the user recording area.

(Operation) According to the present invention, recording information for defective areas and defect management information in a user recording area are recorded in an alternative area and an alternative recording area different from the user recording area.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 6 shows a schematic configuration of an optical disc device in which the disc of the present invention is used. That is, the optical disk (disc) 1 has a spiral or concentric information storage section with a constant pitch in the radial direction, and is rotationally driven by the motor 4.

As shown in FIG. 7, the optical disc 1 has a metal coating layer such as tellurium or bismuth on the surface of a circular substrate made of, for example, glass or plastic. 1a is coated in a donut shape, and a notch or reference position mark 11 is provided near the center of the metal coating layer.

Further, as shown in FIG. 7, on the optical disc 1, the reference position mark 11 is set to "0", and 25
It is divided into 6 sectors. On the optical disc 1, variable length information is recorded over a plurality of blocks, and 300,000 blocks are formed on 36,000 tracks on the optical disc 1.

The number of sectors in one block on the optical disc 1 is, for example, 40 sectors on the inner side and 20 sectors on the outer side. At the start position of the block, a block header A consisting of a block number, track number, etc. is recorded, for example, when the optical disc 1 is manufactured. Furthermore, if 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.

Further, as shown in FIGS. 1 and 2, the optical disc 1 has defect management information recorded on the innermost circumference of the recording 111a, and is composed of alternative areas, for example 100.
An alternative processing area (alternative processing recording area) a for 01-rack is provided, and in addition to this, a user area (user recording area) is provided as a recording area used by the user.
b is provided.

As shown in FIG. 3, the above alternative processing area a has a management information area (primary) C1 in which new and old defect management information f for each byte is recorded in 4, where the same information as this management information area C is recorded. It is composed of a management information area (sub) d to be 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.

As shown in FIG. 4, in the management information area C(, d), new and old defect management information (error management information) f for each byte is recorded in 4. That is, defect management information with updated defect replacement area information at the time of recording is recorded. Here, the same information is written twice, improving the reliability of the defect management information.

As shown in FIG. 5, the defect management information includes initial defect replacement area information Q and recording defect replacement area information. The above initial defect replacement area information q refers to defects during manufacturing, that is, blocks that cannot be recorded during manufacturing (
This is information that specifies an alternative block (alternative area) for a defective area), for example, by reading a block header and storing an alternative block number (alternative area) for a block number (defective area) whose block header cannot be read. This is what we are doing.

The above-mentioned recording defect replacement area information is information that specifies a replacement block (alternative area) for a defect found during recording, that is, a block (defect area) that cannot be recorded correctly during recording. For example, by reproducing the recorded information (after read-after-write), it is determined whether the recording was performed correctly based on whether or not the information was reproduced correctly, and an alternative block number (defective area) for the block number (defective area) that cannot be recorded correctly is determined. In other words, it is information that specifies writing to an area other than the area, which cannot be known until actually writing.

As shown in FIG. 6, an optical head 5 for recording and reproducing information is provided below the optical disc 1. As shown in FIG. The optical head 5 is fixed to a movable part 6 of a DC linear motor 3, which is composed of a movable part 6 and a fixed part 8, and is linearly moved in the radial direction of the optical disc 1, that is, in the directions a and b in the figure, by the movement of the movable part 6. will be moved to Reference numeral 9 denotes a detector for detecting the position of the movable part 6, which uses a so-called overlapped grating detection method to detect two types of different phases depending on the amount of movement of the movable part 6, that is, the optical head 5 (this phase relationship is outputs a detection signal (changes depending on direction).

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 that drives the objective lens in the direction of the optical disc 1, and a focus drive coil that drives the objective lens in the radial direction of the optical disc 1. Tracking drive coil optical disk 1
It is composed of a focusing detector having a pair of photodetectors on the top of which detects whether the laser beam is focused or not, and a tracking detector having a pair of photodetectors that detects whether the laser beam is tracking on the information track. .

Each photodetector outputs a detection signal to a corresponding processing circuit, and each drive circuit applies a predetermined voltage to each drive coil and semiconductor laser.

The control circuit 20 controls the entire apparatus in response to signals from an external device, that is, a host computer (not shown). The linear motor drive circuit 14 includes the control circuit 2
The linear motor 3 is driven in accordance with the target position signal supplied from the sensor 0 and the output signal of the detector 9.

On the other hand, the rotary motor drive circuit 10 determines the speed according to the rotation clock from the motor 4, and controls the speed to the set speed from the control circuit 20. The focus servo circuit 11 adjusts the focus of the objective lens in the optical head 5 in accordance with the detection signal from the detector in the optical head 5, and the focus retracting circuit 16 moves the lens with one force. When changing from a non-working state to a working state, force tsusing is performed accurately.

The tracking servo circuit 12 moves the objective lens in the radial direction of the optical disk 1 in response to a detection signal from the detector in the optical head 5 so that the beam of light emitted through the objective lens in the optical head 5 is centered on the track. It is something that allows you to move.

Further, the tracking servo circuit 12 can temporarily stop the servo operation and generate a track jump drive pulse in response to a track jump pulse from the track jump pulse generation circuit 17 to move the objective lens and move the beam by one track. It is possible.

Further, the bit signal waveform shaping circuit 13 shapes the waveform of the detection signal from the detector in the optical head 5. The binarization circuit 18 is the bit signal waveform shaping circuit 13
This is to binarize the waveform shaped signal from.

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

Furthermore, when the regenerated synchronization clock extraction circuit 23 is supplied with the control signal from the control circuit 20, the regenerated synchronization clock extraction circuit 23 receives the clock signal supplied from the binarization circuit 18 in response to the clock signal supplied from the variable tarlock generation circuit 19. The reproduction synchronization clock recorded at the beginning of the block header A of each block is extracted from the data.

The demodulation circuit 22 generates the binarization circuit 18 in response to the clock signal from the variable clock generation circuit 19, following the reproduction synchronization clock from the reproduction synchronization clock extraction circuit 23.
It demodulates the data supplied from the The serial-parallel conversion circuit 25 converts the reproduced signal supplied from the demodulation circuit 22 from serial data to parallel data in accordance with the clock signal from the variable clock generation circuit 19.

The header discrimination circuit 26 discriminates only header data from the reproduced signal supplied from the demodulation circuit 22 in accordance with the clock signal from one of the variable clock generation circuits. The recording/reproducing header register 29 is connected to the control circuit 2.
Header data to be accessed supplied from 0 is stored.

The header comparator 28 is connected to the ladder register 29 for the recording/reproduction.
The header data stored in the header discrimination circuit 26 and the header data supplied from the header discrimination circuit 26 are compared to see if they match, and when they match, a match signal is output.

Further, the parallel-serial conversion circuit 24 converts a reproduction signal supplied from a recording/reproduction switching circuit 27 (described later) from parallel data to serial data in accordance with a clock signal from the variable clock generation circuit 19.

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

The recording/reproduction switching circuit 27 outputs the reproduction data following the header data to the recording/reproduction data buffer 30 when the coincidence signal is supplied from the header comparator 28 in response to the reproduction control signal from the control circuit 20 . It is something.

Further, the recording/reproduction switching circuit 27 outputs recording data following the header data supplied from the recording/reproduction data buffer 30 to the parallel/serial conversion circuit 24 in response to a recording control signal from the control circuit 20. It is something.

The recording/reproduction data buffer 30 stores reproduction data from the recording/reproduction switching circuit 27 and also stores recording data from the recording/reproduction data transfer circuit 32. The error correction code addition/error correction circuit 31 is
An error correction code based on the Reed-Solomon method, for example, is added to the recording data stored in the recording/reproduction data buffer 30, and errors in the reproduction data stored in the recording/reproduction data buffer 30 are corrected.

The above-mentioned error correction code addition/error correction circuit 31 performs a strict check by performing correction with weak correction ability in the case of read-after-write during recording, and performs correction with normal error correction ability during playback. It has become.

The above-mentioned weak correction ability means that the magnitude of errors that can be corrected is made smaller than that during normal reproduction. Regarding the correction method using cross interleaving in the above error correction code addition/error correction circuit 31, patent application No. 59
Since it was explained in detail in January 2015, it will be omitted here.

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

Further, as shown in FIG. 8, the ROM 42 as a storage circuit stores clock speed information of the optical disk 1 for each 256 tracks, the number of sectors in one block at this clock speed, and the number of sectors within the 256 tracks at the above speed. It stores a conversion table in which the block number corresponds to the starting sector of that block.

Further, when the control circuit 20 is supplied with a block number of a recording or reproducing position, that is, an access position, which is supplied from the host computer via the external interface circuit 33, the control circuit 20 sets the access position in the ROM 42 according to the block number. , and access is performed by the linear motor 3 and optical head 5 while keeping the frequency of the clock signal constant. The above-mentioned clock speed information and calculation of successive access positions are explained in detail in Japanese Patent Application No. 59-32825M, and therefore will not be repeated here.

Further, the control circuit 20 controls the management information area C of the optical disc 1 when setting the optical disc 1 to the device (in the oven).
The latest defect management information read from (, d) is stored in the memory buffer 43, and is also stored in the memory buffer 43 when the optical disc 1 is closed (when the optical disc 1 is removed from the device) or when the defect management information is updated. The stored defect management information is recorded in the first unrecorded area of the management information areas c and d of the optical disc 1 as R new information.

The memory buffer 43 has an integral multiple of the minimum recording unit of data, for example, 4 bytes, which is the same as one block, and as shown in FIG. time defect replacement area information is stored.

Next, the operation in such a configuration will be explained. First, the optical disc 1 is set in this device (when in the oven).

Then, the control circuit 20 first drives the motor 4 to rotate the optical disc 1 at a constant speed. Next, control circuit 2
0 reads the clock speed information and the access position, that is, the track number and start sector number corresponding to the block number corresponding to the management information area C from the ROM 42.

Thereby, the control circuit 20 outputs the clock speed information to the variable clock generation circuit 19. Then, the variable clock generation circuit 19 uses the reference clock from the reference clock generator 41 to generate a clock signal with a frequency (time width) according to the clock speed information supplied from the control circuit 20, and the modulation circuit 21, The signal is supplied to a demodulation circuit 22 , a reproduced synchronization clock extraction circuit 23 , a parallel-serial conversion circuit 24 , a serial-parallel conversion circuit 25 , and a header discrimination circuit 26 .

Also, based on the track number, the control circuit 20 converts the track number into a scale value, and drives the linear motor driver 14 until this scale value matches the position detected by the output of the position detector 9. , to move the optical head 5. Next, when the movement of the optical head 5 is completed, the detection signal from the detector in the optical head 5 is waveform-shaped by the waveform shaping circuit 13 and then sent to the binarization circuit 1.
8 is converted into 2(i!) and supplied to the demodulation circuit 22 and the reproduction synchronization clock extraction circuit 23. Then, the reproduction synchronization clock extraction circuit 23 extracts the reproduction synchronization recorded at the beginning of the block header A from the supplied data. The clock is extracted and output to the demodulation circuit 22.

Thereby, the demodulation circuit 22 demodulates the reproduction synchronization clock and the read signal supplied from the binarization circuit 1B based on the VTT, and outputs it to the recording and reproduction switching circuit 27 via the serial-parallel conversion circuit 25. It is also supplied to the header discrimination circuit 26. And header discrimination circuit 2
6 discriminates only the header data and outputs it to the control circuit 20 and the header comparator 28.

Thereby, the control circuit 20 determines the track to which the optical head 5 corresponds from the header data, and compares 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 the distance is several tens of tracks or more.
If it is within a track, the optical head 5 is moved by the corresponding number of tracks by track jumping.

Then, when the optical head 5 corresponds to the target track,
The header discrimination circuit 26 discriminates only header data and outputs it to the header comparator 28. At this time, the header data of the block corresponding to the target management information area C is stored in advance in two header registers by the control circuit 20, and the header data of the two header registers is supplied to the header comparator 28. Thereby, the header comparator 28 outputs a match signal to the recording/reproduction switching circuit 27 when the header data match. Then, the recording/reproduction switching circuit 27 transfers the reproduction data supplied following the header data to the recording/reproduction data buffer 3.
Output to 0.

The reproduced data in the recording/reproducing data buffer 30 is subjected to error correction 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 each byte is sequentially supplied to the control circuit 20 in the four management information areas c and d.

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. The latest defect management information f is read out by reading the defect management information f located before five consecutive free areas as the latest information. Furthermore, the reliability of the data is confirmed by comparing the R-new defect management information f read from the management information areas c and d.

Next, with the new defect management information stored in the memory buffer 43 as described above, the host computer (not shown) sends the defect management information to the external interface circuit 33.
Assume that a block number to be recorded (accessed) is supplied to the control circuit 20 via the block number. Then, the control circuit 20
checks whether the block number is included in the initial defect replacement area information Q of the memory buffer 43, that is, whether it is an initial defect area. As a result of this check, if the area is not an initial defective area, the block number from the host computer is recorded as the block. Furthermore, if the result of the above check is that the area is initially defective, the substitute block read out based on the initial defect substitute area information q is set as the block to be recorded.

Then, the control circuit 20 uses the conversion table in 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 one variable clock generation circuit. As a result, the variable clock generation circuit 19 uses the reference clock from the reference clock generator 41 to generate a clock signal with a frequency corresponding to the clock speed information supplied from the control circuit 20, and
1. The signal is supplied to the demodulation circuit 22, the reproduced synchronization clock extraction circuit 23, the parallel-serial conversion circuit 24, the serial-parallel conversion circuit 25, and the header discrimination circuit 26.

Further, based on the track number, the control circuit 20 operates in the same manner as when accessing the alternative processing area described above, and makes the beam light of the optical head 5 correspond to the track of the target block.

At this time, the recording data is stored in the recording/reproducing data buffer 30 from the host computer via the external interface circuit 33 and the recording/reproducing data transfer circuit 32.

Then, a matching signal of the block header of the target block is sent from the header comparator 28 to the recording/reproducing switching circuit 2.
7, the recording data in the recording/reproducing data buffer 30 is supplied by the recording/reproducing switching circuit 27 to the parallel-to-serial converting circuit 24. This parallel
The recording data converted into serial data by the serial conversion circuit 24 is subjected to MFM modulation in the modulation circuit 21 and is supplied to the laser drive circuit 15. Thereby, the laser drive circuit 15 drives a semiconductor laser (not shown) in the optical head 5 according to the supplied modulation signal, thereby
Record data.

After this recording, read-after-write is performed. That is, the block in which the above recording has been performed is read.

That is, the control circuit 20, 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.

Then, a matching signal of the block header of the target block is sent from the header comparator 28 to the recording/reproducing switching circuit 2.
7, the recording/reproducing switching circuit 27 supplies the reproduced data from the serial-to-parallel converting circuit 25 to the recording/reproducing data buffer 30. The reproduced data stored in the recording/reproducing data buffer 30 is subjected to error correction by an error correction code addition/error correction circuit 31 using a weak correction capability. As a result, if no correction error (defect) occurs, the control circuit 20 ends the recording process.

Furthermore, if a correction error (defect) occurs as a result of the above, the control circuit 20 determines a replacement block to be used next based on the recording defect moss area information, and re-records the recording data in the replacement block. After performing this recording, read-after-write is performed in the same manner as described above, and if no correction error (defect) occurs, the control circuit 20 uses a replacement block corresponding to the defective block to store the defect replacement area information at the time of recording in the memory buffer 43. and also this memory buffer 4
3 is recorded in management information areas c and d. Also,
If a correction error (defect) occurs, the control circuit 20 records the recorded data again in another alternative block, and thereafter operates in the same manner as described above.

Furthermore, data can be recorded in other blocks in the same manner as described above. In this case, data is recorded with the frequency of the clock signal increased as the block position is located on the outer circumferential side.

Incidentally, the operation during the above recording is as shown in FIG.

It is also assumed that a block number to be reproduced (accessed) is supplied to the control circuit 20 from a host computer (not shown) via the external interface circuit 33.

Then, the control circuit 20 determines that the process number is the initial defect replacement area information of the memory buffer 43! 11g, that is, whether it is an initial defective area. As a result of this check, if the area is not an initial defective area, the block number from the host computer is used as the block to be reproduced. Furthermore, if the result of the above check is that the area is initially defective, the substitute block read out based on the initial defect substitute area information q is set as the block to be reproduced.

Then, as in the case of recording above, the clock speed information corresponding to the block (block number from the host computer or alternative block) is read out, and a clock signal of a frequency corresponding to this clock speed information is transmitted to the modulation circuit 21. Demodulation circuit 22, reproduction synchronization clock extraction circuit 23
, a parallel-serial conversion circuit 24, a serial-parallel conversion circuit 25, and a header discrimination circuit 26.

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

Then, a matching signal of the block header of the target block is sent from the header comparator 28 to the recording/reproducing switching circuit 2.
7, the recording/reproducing switching circuit 27 supplies the reproduced data from the serial-variable/reconverting circuit 25 to the recording/reproducing data buffer 30. The reproduction data stored in the recording and reproduction data buffer 30 is subjected to error correction by an error correction code addition/error correction circuit 31 using normal error correction capability. As a result, if no correction error (defect) occurs, the control circuit 20 transfers the reproduced data to the host computer via the recording/reproduction data transfer circuit 33 and the external interface circuit 33, and ends the reproduction process.

If a correction error (defect) occurs as a result of the above, the control circuit 20 reads a 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 using the normal error correction capability in the same manner as described above. Then, the control circuit 20 transfers the reproduced 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 process.

Further, when reproducing data of another block, it can be performed in the same manner as described above. In this case, data is reproduced with the frequency of the clock signal being increased as the block position is located on the outer circumferential side.

Note that the operation during the above-mentioned reproduction is as shown in FIG.

Furthermore, when the optical disc 1 is removed (when closed) or when the defect management information is updated, the control circuit 20 updates the defect management information stored in the memory buffer 43 to R'f.
Management information area cSd of optical disc 1 as IT information
recorded in the first unrecorded area.

As mentioned above, alternative blocks for defective blocks in the user area are recorded in an area different from the user area, so they can be used without reducing the actual recording capacity of the user area. Furthermore, since the positions of the management information area and the alternative block area are fixed on the optical disc, there is compatibility between the discs.

In the above embodiments, an optical disk is used as the information recording medium, but the information recording medium is not limited to this, and may be a magnetic disk, a floppy disk, a laser card, or the like.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to use the information recording medium without reducing the actual recording capacity of the user recording area, and to provide two information recording media that are compatible with each other in terms of defect management. can.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a plan view showing the configuration of a disk, FIG. 2 is a plan view illustrating an alternative processing area and a user area, and FIG. 3 is a plan view showing an alternative processing area. A plan view for explaining the configuration of the processing area, FIG. 4 is a diagram showing an example of recording in the management information area, FIG. 5 is a diagram for explaining an example of recording defect management information, and FIG. 6 is an optical disk. FIG. 7 is a diagram schematically showing the configuration of the apparatus, FIG. 7 is a diagram showing the configuration of an optical disk, FIG. 8 is a diagram showing an example of storage of a conversion table, FIG. 9 is a diagram for explaining an example of storage of a memory buffer, FIG. 10 is a flowchart for explaining the recording operation, and FIG. 11 is a flowchart for explaining the reproduction operation. DESCRIPTION OF SYMBOLS 1... Optical disc (information recording medium), 1a... Recording film, a... Area for alternative processing (recording area for alternative processing), b... User area <user recording area, c,
d: Management information area, e: Alternative block area, f: Defect management information, q: Initial defect replacement area information, h: Recordability defect replacement area information. Applicant's representative Patent attorney Takehiko Suzue @Figure 2 Figure 3 f Unrecorded Figure 4 Figure 5 Figure 7 Figure 9 Figure 10

Claims (2)

[Claims] (1) It has a user recording area used by the user and an alternative area for alternatively recording the information recorded in the defective area in this user recording area, and has defect management information indicating the alternative area for the defective area in the user recording area. An information recording medium comprising: a recording area for alternative processing for storing information; (2) Defect management information is composed of initial defect replacement area information indicating a replacement area for initial defects during manufacturing and recording defect replacement area information indicating a replacement area for defects during recording. An information recording medium according to claim 1 characterized by: