JPH06176361A - How to manage data - Google Patents

Abstract

(57) [Summary] [Structure] The number of rewrites for recording / erasing including the prewrite test area of the disk is registered in the data management area of the disk, and the number of rewrites in a certain area on the disk is not concentrated so that it does not concentrate. Measures on the device to be dispersed in and the soft measures were taken. [Effect] Since the number of times of rewriting on the disk is not concentrated on a certain track or a certain sector, it is possible to greatly improve the utilization efficiency of the track, since it is less necessary to take measures such as a replacement sector and recording prohibition. . At the same time, the life of the disc could be greatly extended.

Description

Detailed Description of the Invention

[0001]

The present invention relates to recording using laser light,
The present invention relates to a rewritable optical recording for reproducing or erasing, and particularly to a data management method suitable for stable recording / reproducing and obtaining a highly reliable optical disc.

[0002]

2. Description of the Related Art With the progress of the advanced information society in recent years, there is an increasing need for a high-density and large-capacity file memory. Among them, optical recording has attracted attention as one that meets this need. Among them, the magneto-optical recording and the phase change type optical recording which have recently been put into practical use are used as rewritable type optical recording in many fields including image files and document files. At present, research and development are being pursued with the aim of further improving performance, such as improving recording density and enabling overwriting. At the center of this is the further improvement in recording density. Therefore, it is known that it is effective to perform recording and reproduction using a light source having a short wavelength. In this case, the shorter the wavelength of light,
On the other hand, the energy density per unit area becomes high, although it can be narrowed down to a minute spot. As a result, when recording / erasing is repeated, the recording medium physically deteriorates in the phase change optical recording,
Further, in magneto-optical recording, the magnetic characteristics may change due to structural relaxation of the recording film or the like, which may reduce the signal output, and reliability may not be ensured. On the other hand, this problem has been solved by devising the structure of the recording medium and the fabrication process of the recording film.

[0003]

The above-mentioned conventional technique has sufficient recording accuracy for the conventional pit position recording system, but does not necessarily have sufficient precision for the mark length recording system. Didn't. That is, there is a problem that the reproduction signal output decreases when recording and erasing are repeated.

An object of the present invention is to record signals on an optical disc by equalizing the number of times recording / erasing is repeated in the recording area (the number of times of rewriting) in any area so that a signal generated by repeating recording / erasing can be obtained. It is to provide a data management method that does not cause a reduction in output.

[0005]

In order to achieve the above object, in rewritable optical recording in which recording, reproduction, or erasing is performed using at least a laser beam, information is recorded on the disc in order to record information on the disc. Area and record /
The number of repetitions of erasure may be recorded in the data management area, and information to be recorded may be managed so that the number of repetitions of recording / erasure is not biased to any area when recording on the disc. Alternatively, in order to record information on the previous disc, the area where information is recorded on the disc and the number of times of recording / erasing are recorded in the data management area, and the recording / erasing is performed to record on the disc. The information to be recorded may be managed so that the number of repetitions increases from the inner peripheral portion toward the outer peripheral portion. Here, when information is recorded on the disc, recording / erasing is performed under a constant rotation number of the disc. This is to register the number of rewrites of recording / erasing including the prewrite test area of the disk in the data management area of the disk, and to distribute so as not to concentrate, such as when the number of rewrites of a certain area on the disk increases. Measures and soft measures were taken.

[0006]

In recording on the disc, the area where the number of times of recording / erasing is repeated is not biased to a specific area in a certain area, so that the reproduced signal output of the same intensity is always obtained in any area.

[0007]

【Example】

Example 1 FIG. 1 shows the cross-sectional structure of the optical disc manufactured in this example. The disk has a silicon nitride film 2 having a thickness of 75 nm on a disk substrate 1 having an uneven guide groove.
Formed. Next, a TbFeCoNb film was formed as the recording film 3 to a film thickness of 25 nm. Subsequently, the silicon nitride film 4 was again formed to have a film thickness of 20 nm. Finally, an Al ₉₃ Ti ₇ film is formed as the metal layer 5 to a film thickness of 50 nm,
An optical disc was produced.

Recording was performed on this optical disk. In that case, the recording position on the disk such as a sector in which information is recorded and the number of times recording / erasing is repeated are recorded in the data management area. Then, each time the information in the area is rewritten, the number of times accumulated up to that time is recorded in the previous data management area. At the same time, in determining the recording area, recording was performed in the area in which the number of times of rewriting was the smallest. And record /
Recording was performed so that the number of times of rewriting, which is repetition of erasing, was uniform.

As a result, the mark length recording method was used for recording in the entire area, and recording was performed by the (1,7) modulation method.
In addition, MC so that the recording density on the disk is constant
The AV method was used. The wavelength of light used for recording and erasing is 63
It is 0 nm. When recording or erasing, the recording is first performed from the outer peripheral portion, and the number of rewriting is reduced toward the inner peripheral portion.

Innermost circumference position of 5.25 inch disc (r
= 30 mm), the edge shift was ± 2 ns or less at any position up to 10 ⁷ times of recording / erasing. But,
When it exceeds 6 × 10 ⁷ times, the value increases slightly to ± 5 ns.
Became. Jitter also increased from the initial value and was 35% or less with respect to the detection window width, but increased by repeated recording / erasing to 48%. This is the case where recording / erasing was concentrated on a certain track, and the number of rewrites was registered according to the present invention, and recording was performed so that the number of rewrites was uniform over the entire surface of the disc. Then, according to the registered number of times of rewriting, the recording condition is optimized by a pre-write test, or the recording to that portion is prohibited. According to the present invention, the life of the disk can be greatly extended.

<Embodiment 2> FIG. 1 shows the cross-sectional structure of the optical disk manufactured in this embodiment. For the disc, a silicon nitride film 2 having a film thickness of 75 nm was formed on a disc substrate 1 having an uneven guide groove. Next, GeS is used as the recording film 3.
The bTe film was formed to a thickness of 40 nm. Subsequently, the silicon nitride film 4 was again formed to have a film thickness of 20 nm. Finally, an Al ₅₀ Ti ₅₀ film was formed as the metal layer 5 to a film thickness of 50 nm, and an optical disc was produced. The optical disc was manufactured by the all-sputtering method.

Recording was performed on this optical disk. In that case, the recording position on the disk such as a sector in which information is recorded and the number of times recording / erasing is repeated are recorded in the data management area. Then, each time the information in the area is rewritten, the number of times accumulated up to that time is recorded in the previous data management area. At the same time, in determining the recording area, recording was performed in the area in which the number of times of rewriting was the smallest. And record /
Recording was performed so that the number of times of rewriting, which is repetition of erasing, was uniform.

As a result, the carrier-to-noise ratio (C / N) did not change after rewriting 5 × 10 ⁵ times. But 5
The noise level increased by about 3 dB after rewriting 10 ⁶ times. After that, the noise level increased as the number of rewrites increased, and eventually recording / playback became impossible. this is,
This is the result of recording / erasing concentrated on a certain track. Actually, recording / erasing was concentrated on a certain track according to the present invention.
Since no erasing is performed and the number of times of rewriting is registered in all sectors, it is only necessary to take measures such as optimizing the recording conditions by a prewrite test according to the number of times of rewriting, or prohibiting recording on that portion. . According to the invention,
We were able to extend the life of the disc significantly.

[0014]

According to the present invention, since the number of times of rewriting on the disk is not concentrated on a certain track or a certain sector, it is less necessary to take measures such as a replacement sector and recording prohibition. It can be greatly improved. At the same time, the life of the disc could be greatly extended.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a cross-sectional structure of a prototype optical disc.

[Explanation of symbols]

1 ... Disk substrate, 2 ... Silicon nitride film, 3 ... Recording film,
4 ... Silicon nitride film, 5 ... Metal layer.

Claims (3)

[Claims] 1. A rewritable optical recording method for recording, reproducing, or erasing by using a laser beam, wherein data indicating an information recording area on a disc and recording / erasing repetition count data are recorded in a data management area. A data management method is characterized in that the number of times of recording / erasing is controlled so as not to be biased to any area on the disk when recording on the disk. 2. A rewritable optical recording method for recording, reproducing, or erasing by using a laser beam, wherein the information recording area on the disk and the number of times of recording / erasing are repeated for recording information on the disk. The data is recorded in a data management area, and the information is recorded so that the number of times of recording / erasing is increased from the inner peripheral portion toward the outer peripheral portion in order to record on the disc. How to manage data. 3. A data management method for recording / erasing information when recording the information according to claim 1 or 2 on the disc under a constant rotation speed of the disc.