JPH02156477A - Optical information recording disk - Google Patents

Abstract

PURPOSE:To prevent probability to relieve the defect of a zone at an outer peripheral part from being lowered by varying and arranging the number of substitute sectors on one track at every zone divided in the direction of radius of gyration of a disk. CONSTITUTION:In an optical disk 1, a concentric circular shape track 2 is divided into the zones 10-12. The same number of sectors 3 on one track is provided in each of the zones 10-12. Also, one substitute sector 104 is provided on every track in the zone 10, two substitute sectors 114 on every track in the zone 11, and three substitute sectors 124 on every track in the zone 12. Thus, it is possible to reduce an error rate at the outer peripheral part by increasing the number of substitute sectors in the zone at the outer peripheral part to one, two,....

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an optical information recording disk.

The track on the disk is divided into a plurality of zones in the direction of the rotation radius, and the zones nearer to the outer periphery record at a lower rotation speed, and within each zone, recording is performed at a constant rotation speed, and then alternate to each of the tracks. The present invention relates to an optical information recording disk having sectors.

[Conventional technology]

Optical information recording disks (hereinafter referred to as optical disks) have tracks arranged concentrically or spirally, and each track has multiple sectors in order to record variable length data and speed up access. optical recording and reproduction is performed sector by sector.

Information is recorded by focusing the radar light emitted from the semiconductor radar onto the recording layer on the disk, and drilling holes in the recording layer.
Alternatively, recording pits may be formed by changing reflectance or transmittance.

The format of data recording density is roughly divided into two types: the CLV method, in which the recording pits are recorded on the disk at a constant linear velocity, and the CAV method, in which the recording pits are recorded at a constant angular velocity.

In the CAV method, since recording is performed at a constant angular velocity, the outer circumference of the disk has a lower data recording density per unit length than the inner circumference, and is inferior in terms of efficient use of storage capacity.

Also, in the CLV method, the sectors are not arranged in a radial manner, so
Furthermore, since the number of rotations differs depending on the position, there is a drawback that access time becomes long.

Therefore, the 7'j MCAV system has been proposed in JP-A-59-167874, which has both the easy access of the CAV system and the advantages of the recording density of the CLV system. In other words, the disk is divided into multiple zones in the direction of the rotation radius,
Recording is performed by lowering the rotation speed toward the outer zone, and recording at a constant rotation speed within each zone, thereby achieving 9 C.
A method has been proposed that improves the drawback of the AV method, which is that the recording density decreases as the number of peripheries increases.

On the other hand, defects on the f disk do not have any adverse effects during recording and reproduction. Normal information recording and reproducing operations are interrupted in an incomplete state by causing a detection error in the sector ID part during information recording and reproducing operations, or by causing a dragging error (AT misalignment) during information recording and reproducing operations. Furthermore, the ECC capability of the optical information recording/reproducing device may be exceeded and the following errors may occur.

In order to avoid these errors, it may be possible to completely detect defects across the entire surface of each medium before shipping, as with magnetic disks, but this would be disadvantageous in terms of cost, and the Since such media cannot be erased in principle, it is not possible to record for defect detection.

Therefore, in order to logically avoid defects, a playback operation is performed immediately after the actual recording operation.

When a defective location is detected, an alternative processing method is essential, in which the block is rewritten to a predetermined replacement block.

Generally, in replacement processing on the original disk, data is layered into various stages using sectors, tracks, etc. as units of recording and playback, according to the data format on the medium.

Blocks that do not meet the standards of recording quality set at each stage are replaced with pre-prepared replacement blocks.

[Problem to be solved by the invention]

However, when one replacement sector is prepared in a track consisting of multiple sectors, the defect recovery probability for one track is common to all tracks in the CAV method, but
In the MCAV method, since the number of data sectors within one track differs from zone to zone, there is a problem in that the probability of defect repair is lower in zones closer to the periphery. Further, for this reason, there is a problem in that it is undesirable to record highly important information such as disk management information in an area on the outer periphery where the probability of repairing defects is low.

In view of the above, an object of the present invention is to provide an optical disc that can record and reproduce data using the MCAV method, and can prevent a decrease in the probability of repairing defects in the outer peripheral zone.

[Next means to solve the problem]

To achieve the above object, the track on the disk is divided into a plurality of zones in the direction of the rotational radius, and recording is performed by lowering the rotational speed toward the zones closer to the outer periphery.

And within each zone, recording is performed at a constant rotation speed.

Furthermore, there is provided an optical information recording disk having alternate sectors in each track, wherein the number of alternate sectors in the l track is varied and arranged for each zone. Ru.

〔Example〕

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

FIG. 1 shows a schematic diagram of the format of an optical disc according to a first embodiment of the present invention. FIG. 1 is a schematic diagram, and in an actual disc-shaped optical disc, the left end IIj 121 and the right end line 22 are connected.

The optical disc 1 according to this embodiment has a concentric track 2 divided into three zones 10, 11, and 12. In each zone 10j11.12, the number of sectors in one track is equal; in this embodiment, zone IO has 10 sectors in one track, and zone 11 has 11 sectors in one track.
In sector and zone 12, 12 sectors are provided in one track.

The hatched sectors in FIG. 1 are replacement sectors prepared in advance for replacement processing. In this embodiment, zone 10 has one sector 104 for each track, and zone IIK has two sectors for each track. Three sectors 124 are provided in each track in the zone 12. Therefore,
The user data area is 97 data across all tracks. Further, in this embodiment, the replacement sector 104 of zone 10 is set to the last sector of any track, the replacement sector 114 of zone 11 is set to the last sector of any track and the sector immediately before it, and zone 12 is set to the last sector of each track.
The replacement sector 124 is the last part of any trunk.
It is set to sector.

The optical disc according to the present embodiment is configured as described above, and if a certain sector 3 is recorded in zone 10 and it is a bad sector, it is replaced with the last sector of the same track and recorded in zone 11. , if a certain sector is recorded and it turns out to be a bad sector, it will be replaced with one of the two sectors at the end of the same track, and if that sector is bad or in the data area. If there is another defective sector on the same track, the remaining sectors of the last two replacement sectors 114 are replaced. The same applies to the zone 12, and in this case, three replacement sectors 124 can be subjected to replacement processing.

Now, suppose that the sector defect rate is E8, and the track error rate in the above configuration is Et.

It is expressed by the formula. Here, a indicates the number of alternate sectors in one track, and n indicates the total number of sectors in the track.

Now, the track error rate in zone 10 is EH8, and the error rate in zone 11.12 is Et11'"t12.
Then, each becomes E,. The relationship is ≧Et11≧”t12.

As can be seen from this relationship, by increasing the number of replacement sectors in the outer zone by one, two, etc.
It is possible to lower the error rate on the outer periphery.

In this embodiment, the replacement sectors 104, 114° 124
is placed in the last part of the track, but it may be placed in other parts of the track.

FIG. 2 shows a schematic diagram of the format of an optical disc according to a second embodiment of the present invention. Figure 2 is a schematic diagram similar to Figure 1.
In an actual disc-shaped optical disc, the left end 1s2
1 and the right m line 22 are connected.

In this embodiment, the positions of the replacement sectors are dispersed in the tracks of each zone. The other configurations, such as the number of sectors in each zone and the number of replacement sectors, are the same as those in the first embodiment, so their explanation will be omitted.

The optical disc according to the present embodiment is configured as described above. In the disk 710, if a certain sector 3 is recorded and it turns out to be a bad sector, replacement processing is performed on a replacement sector at any position on the same track. In zone 11, if a certain sector is recorded and it turns out to be a bad sector, it is replaced with one of two replacement sectors located somewhere on the same track, and if that sector is also bad. If there is another defective sector in the data sector of the same track, the remaining sector of the two replacement sectors 114 is replaced. The same applies to zone 12, and in this case, replacement processing is possible for three replacement sectors 1241C located at any position.

The track pitch of an optical memory is usually about 1.6 μm, and the track density is high. On the other hand, there are about ten sectors in one track. If the temporary sheet has a defect with a diameter of about 30 μm,
Sectors spanning 20 tracks become bad sectors. By the way, if the position of the replacement sector for each track is fixed as shown in FIG. 1, the probability that the replacement sector will be defective and become useless after use increases accordingly.

Therefore, by distributing the replacement sectors as in this embodiment, it is possible to reduce the probability that the replacement sectors become unusable due to defects.

Above 1. In the second embodiment, the tracks are arranged concentrically, but it goes without saying that the present invention can also be applied to an optical disk in which tracks are arranged spirally.

Also, the above 1. In the second embodiment, the number of data sectors in each zone is equal to 9 sectors, but the number of data sectors may be different in each zone.
Furthermore, the above 1. In the second embodiment, it is composed of three zones, and each zone has 10 sectors in one track.
11 sectors.

Although it is assumed that the track is composed of 12 sectors, this is just an example; the number of zones, the number of sectors in one track in each zone, the number of alternate sectors, etc. can be freely designed according to the purpose. be.

〔Effect of the invention〕

In the optical information recording disk according to the present invention, since the number of replacement sectors in one track is varied and arranged for each zone, it is possible to prevent a decrease in the probability of repairing defects in the outer peripheral zone. .

Furthermore, if the positions of the replacement sectors are distributed in the tracks of each zone, it is possible to reduce the probability that the replacement sectors will become unusable due to defects.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the format of an optical disc according to the first embodiment of the present invention, and FIG. 2 is a schematic diagram of the format of the optical disc according to the second embodiment. 1... Optical disk, 2... Track, 3... Sector. 10.11.12...Zone, 104,114.12
4...Replacement sector. Figure 1

Claims (3)

[Claims] (1) The track on the disk is divided into a plurality of zones in the direction of the rotation radius, and recording is performed at a lower rotational speed as the zones near the outer periphery, and recording is performed at a constant rotational speed within each zone, and furthermore, each of the zones is recorded at a lower rotational speed. 1. An optical information recording disk having alternate sectors on a track, wherein the number of alternate sectors in one track is varied and arranged for each zone. (2) The number of sectors other than the replacement sector in the one track is made the same in all of the zones, so that the number of the replacement sectors is larger in the outer peripheral part of the zone. The optical information recording disc according to claim 1. (3) The optical information recording disk according to claim 1 or 2, wherein the positions of the replacement sectors are dispersed in the tracks of each zone.