JPH05101392A - Method for recording optical information - Google Patents

Abstract

PURPOSE:To provide an optical information recording method preventing recording shortage due to the lowering of sensitivity from generating in the optical recording medium of an MCAV system. CONSTITUTION:The disk like optical recording medium is used, which is manufactured base on an MCAV format and provided with a directory information recording part 2 on an inner peripheral side. Information is recorded in the optical recording medium from the outer peripheral side. Thus, even when the sensitivity is lowered by the long term use of the medium, the generation of the recording shortage is prevented, and since the directory information is not damaged, the reliability is improved further.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording method,
Specifically, it relates to improvement of an optical information recording method using the MCAV system.

[0002]

2. Description of the Related Art Conventionally, as a rotational driving method for an optical information recording disk, a constant angular velocity (CAV) method, a constant linear velocity (CLV) method, and a constant angular velocity recording area are used. Has been proposed in which the clock frequency is divided into a plurality of blocks in the radial direction and the clock frequency is changed for each block (Modified CAV, MCAV).

[0003] The CAV system has the advantages that random access is excellent and data can be transferred at a high speed because the sector position can be specified radially around the center of rotation of the optical information recording disk. Since the data clock frequency is fixed, the linear velocity increases in proportion to the increase in the radial position of the selected sector,
There is a problem that the recording density decreases.

On the other hand, in the CLV system, the rotation speed of the optical information recording disk is controlled so that the linear velocity becomes constant irrespective of the radial position of the sector. It has the advantage that it can be made uniform and enables high-density recording, but on the other hand, the seek speed is slow because the rotational speed of the disk drive motor must be controlled by the radial position of the sector, and the sector Since the positions cannot be specified radially, there is a problem that the random accessibility is poor and the data transfer rate is slow.

Further, the MCAV system can be provided with an intermediate feature between the CAV system and the CLV system by setting the data clock frequency for each block divided in the radial direction, but at the outer peripheral portion. Since the clock frequency becomes high, the energy required for recording becomes large.

On the other hand, when the optical recording medium is used for a long period of time, there is a possibility that the recording sensitivity may be slightly lowered due to the change in the characteristics of the recording film. Moreover, the recording sensitivity is lowered due to the adhesion of dust to the surface of the medium. Therefore, M
In the CAV method, there is a possibility that recording may be insufficient at the outermost peripheral portion of a medium that has been used for a long time even if there is no problem initially. Especially when the directory information is lost, it is inconvenient to use the entire medium.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide an optical information recording method which does not cause recording shortage due to a decrease in sensitivity of a medium.

[0008]

In order to achieve the above object, according to the present invention, a system for recording / reproducing information by using a clock frequency at the outer periphery of the disc-shaped optical recording medium is set higher than that at the outer periphery thereof. In the optical information recording method, there is provided an optical information recording method characterized by recording information from the outer peripheral side of a disc-shaped optical recording medium.

When recording from the outer peripheral portion, there is a method of sequentially recording from the outermost peripheral portion of the track, but this is not preferable because it takes access time when recording and reproducing a large amount of information over several tracks. Therefore, in practice, it is preferable to divide the recording portion according to the radial position of the medium and sequentially use the outer peripheral zone. In each case, recording may be performed from the inner circumference side. The outermost zone starts at a position of 1/3 or less and 1/30 or more from the outer circumferential side in the radial direction.

Further, according to the present invention, there is provided an optical information recording method characterized by using a disc-shaped optical recording medium having a directory information recording portion provided in an inner peripheral portion in the above structure.

Further, according to the present invention, in the above structure, a plurality of zones are provided in the radial direction of the disk-shaped optical recording medium, recording is preferentially performed in the outer peripheral side zone, and a plurality of zones in the outer peripheral side zone are provided. There is provided an optical information recording method, characterized in that recording is performed from a track closer to the medium center side of the track.

[0012]

According to the present invention, there is little margin in the recording sensitivity, and when the recording film is deteriorated due to long-term use of the medium or the sensitivity is reduced due to the adhesion of dust to the medium surface, information is highly likely to be recorded from the outer peripheral side. Since the recording is performed, the outer peripheral portion is used before the total use time after the medium is manufactured is short. That is, since the outer peripheral portion is used before the sensitivity is insufficiently generated for a long period of time, the above-mentioned trouble can be avoided. Further, by providing the directory information recording portion on the inner peripheral portion, the directory information is not lost even if the medium is used for a long period of time, and the use of the entire medium is not inconvenient.

[0013]

The present invention will be described in detail below. FIG. 1 is a diagram showing a disc-shaped optical recording medium used in the method of the present invention.
Is an information recording unit, 2 is a directory information recording unit, and the directory information recording unit 2 is provided on the inner peripheral side. Moreover, this optical recording medium is manufactured based on the MCAV format.

FIG. 2 is an explanatory diagram of the MCAV format.
(A) is an outline, (b) is the relationship between the radial position and the rotation speed,
(C) shows the relationship between the radial position and the clock frequency. In the figure, 3 is a track, 4 is an outer sector, and 5 is an inner sector. Since the MCAV type optical recording medium is used while being rotated at a constant speed, the linear velocity becomes faster and the recording / reproducing frequency becomes higher toward the outer periphery, so that the recording sensitivity margin of the medium becomes smaller. The decrease in the sensitivity of the medium is caused by the attachment of dust to the medium surface or the change in the characteristics of the recording film. The adhesion of dust to the surface of the medium occurs when the medium is mounted in the device and used, and hardly occurs when the medium is left unused outside the device. That is, since the sensitivity decrease of the medium occurs in correlation with the usage time of the medium, there is no problem in storing the medium for a long time without using it. In addition, the change in the characteristics of the recording film is caused by the temperature stress when the medium is mounted and used in the apparatus.

In the MCAV system, since the clock frequency of the outer peripheral portion is high as described above, the outer peripheral portion has a smaller margin in terms of recording sensitivity. In recording on a medium having an outer peripheral portion in such a situation, recording with the same energy is performed in all areas, but if, for example, the same amount of dust adheres to the medium surface, it is recorded as the entire area. The sensitivity decreases, and due to the decrease, the outer peripheral portion may exceed the limit of recordability and may become unrecorded.

In view of this, the present invention avoids the recording shortage due to the sensitivity decrease by using the outer peripheral portion which is easily affected by the sensitivity decrease before the sensitivity decrease occurs. That is, as shown in FIG. 1, in the present invention, there is little margin in recording sensitivity, and recording may be insufficient when the recording film is deteriorated due to long-term use of the medium or the sensitivity is reduced due to adhesion of dust to the surface of the medium. Since information is recorded from the high outer peripheral side, the outer peripheral portion is used while the total usage time after the medium is manufactured is short. That is, since the outer peripheral portion is used before the sensitivity is insufficiently generated for a long period of time, the above-mentioned trouble can be avoided.

Further, in the present invention, as described above, the directory information recording section 2 is provided in the inner peripheral portion. The directory information is the address information in which information is recorded, and is rewritten or additionally recorded before recording new information. Therefore, by recording this directory information in a portion where the recording condition of the inner peripheral portion is loose, the integrity of the information can be improved despite the decrease in recording sensitivity due to long-term use of the medium.

The method of the present invention can be carried out regardless of whether the recording format of the medium is the write once type or the rewrite type.

[0019]

According to the present invention, information is recorded from the outer peripheral portion of an MCAV type optical recording medium, so that the medium can be used without being affected by sensitivity deterioration due to long-term use. Moreover, since the directory information is recorded in the inner peripheral portion, the reliability of the information can be further improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a process of recording information on a disc-shaped optical recording medium by the method of the present invention.

2A and 2B are explanatory diagrams of the MCAV format, where FIG. 2A is a schematic diagram, FIG. 2B is a relationship between a radial position and a rotation speed, and FIG. 2C is a relationship between a radial position and a clock frequency.

Claims (3)

[Claims] 1. An optical information recording method using a method of recording and reproducing information by increasing the clock frequency of the outer circumference than the inner circumference of the disc-shaped optical recording medium, wherein the information is recorded from the outer circumference side of the disc-shaped optical recording medium. A method for recording optical information, which comprises: 2. The optical information recording method according to claim 1, wherein a disc-shaped optical recording medium having a directory information recording portion provided on an inner peripheral portion thereof is used. 3. A disc-shaped optical recording medium is provided with a plurality of zones in a radial direction, recording is preferentially performed in an outer peripheral side zone, and recording is performed from a track near a medium center side of a plurality of tracks in the outer peripheral side zone. The method according to claim 1, wherein
The optical information recording method described in.