KR19980074867A - Optical recording medium and recording method thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium capable of preventing deterioration of information on adjacent tracks due to a plurality of repeated recordings in a high density optical disc, and a recording method thereof.

The optical recording medium of the present invention includes a data recording area in which data is continuously recorded in tracks, and a file management area in which data is recorded by skipping tracks one by one.

The optical recording medium recording method of the present invention comprises a first step of identifying whether a data recording area is a data recording area or a file management area, and continuously recording data in tracks when the data recording area is determined in step 1; And a third step of recording data by skipping tracks one by one when the file management area is determined in step 1.

According to the present invention, the file management area can perform land-only recording or groove-only recording to widen the distance between tracks on which data is recorded, thereby preventing information deterioration of adjacent tracks even during a plurality of repeated recordings.

Description

Optical recording medium and recording method thereof

1 is a cross-sectional view showing the structure of a general phase change type optical disk.

2 is a diagram showing in detail the information recording surface of the optical recording medium according to the optical recording medium recording method of the present invention.

* Description of the symbols for the main parts of the drawings *

1 substrate 2 lower dielectric layer

3: information recording layer 4: upper dielectric layer

5: Reflective Film 6: Ultraviolet Protection Layer

7: information recording surface 8: land

9: groove 10: feet

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium capable of recording information by light beams, and particularly to cross-talk and cross-eraser, which degrades information of adjacent tracks in a plurality of repetitive recordings in high density optical discs. An optical recording medium capable of preventing the phenomenon and a recording method thereof.

Optical recording media (hereinafter referred to as optical disks) have been put to practical use by read-only compact discs (CDs), and in recent years, magneto-optical discs and phase change type optical discs have been put into practical use as optical discs capable of repeating recording. Here, the recording capacity of the phase change type optical disk is about 650 MByte, and recently, a so-called 2.6 GByte Digital Versatile Disc-Random Access Memory (DVD-RAM) disk which has been increased by about four times is expected to be put to practical use soon.

In general, a phase change type optical disc capable of repeating recording can rewrite information by irradiating a light beam onto the information recording surface to change the physical characteristics of the material constituting the information recording surface. In other words, the phase change type optical disc erases recorded information and records arbitrary information by phase-changing the coupling structure of the recording surface to a crystalline phase and an amorphous phase by irradiating a light beam on the information recording surface. Typically, the region of the crystalline structure of the disk has a high reflectivity for the light beam while the region of the amorphous structure has a relatively low reflectance for the light beam. At this time, the crystalline phase becomes a portion without information, that is, '0', and the amorphous phase becomes a recording bit, that is, '1', so that binary data recording is possible. That is, the information is read as the difference between the crystalline and the amorphous reflectivity. Therefore, in order to record information on such an optical disc, a light beam of sufficiently large energy that the coupling structure of the information recording surface can be changed must be used, and when the information recorded on the optical disc is reproduced, the coupling structure of the information recording surface is relatively unchanged. Small energy light beams should be used.

The technical problems that are most prominent in such phase change type optical discs can be roughly classified into problems related to the expansion of the recording capacity and problems related to the increase in the number of repetitive recordings. Accordingly, the problem related to the expansion of the recording capacity could be solved by the land and groove recording method. In other words, the land and groove recording methods have an effect of increasing recording density by about twice as compared with the conventional methods of recording only land or grooves. On the other hand, in order for an optical disc to be used as an information recording medium, it must be possible to repeatedly record information many times. However, recently, as the structure of optical discs has been increased, there has been a problem in that cross-talk and cross-laser phenomena deteriorate when information is repeatedly recorded. The problem with the conventional optical disc will be described with reference to the accompanying drawings.

1 is a cross-sectional view showing the structure of a general phase change type optical disc, wherein the phase change type optical disc has a lower dielectric layer 2, a recording layer 3, and an upper dielectric layer 4 continuously stacked on top of the transparent substrate 1; And a reflective film layer 5. In addition, an ultraviolet protective layer 6 is formed on the reflective layer 5.

In order to increase the recording density in the phase change type optical disc having such a structure, techniques such as the use of a short wavelength, for example, a laser of 680 nm or 650 nm, land and groove recording, and a short track pitch application have been developed. Among them, land and groove recording techniques are essential for increasing the density of optical discs in such a way that they can double the density of the discs.

However, in the land and groove recording method, since the distance between adjacent tracks is reduced by half, reflection occurs in the adjacent tracks during data reading, resulting in a large cross-talk phenomenon in which data of the adjacent tracks is read. In addition, a cross-laser phenomenon, which thermally affects data of adjacent tracks during a plurality of repeated recordings, erases data of adjacent tracks already recorded. This phenomenon has become even larger as the track structure becomes smaller, especially as the disk structure is adapted to higher density. In particular, the cross-erase problem becomes more serious as the number of repetitive writes increases.

In fact, in the optical disc capable of repeatable recording, the number of times of repeat recording that can cause the above problems is thousands or more, and only about 1% of the entire disc area is generated by this number of times. In other words, the portion where information deteriorates due to thousands of repetitive recordings is a file management area (FAT) in the DOS format of the entire area of the disk, and the table of content (TOC) in the CD format. This is the part. The file management area is actually located in the innermost or outermost part of the optical disc. In addition, it is expected that the recording formats of the optical discs to come out are not significantly different from the above two methods. In other words, the file management area will be recorded separately from the actual data area referring to this part.

Therefore, if the cross-erase problem occurring in the file management area where a lot of repetitive recording is performed is solved, the cross-erase problem can be solved for the entire disk.

In this regard, a method for solving the conventional optical disc problem is disclosed in US Pat. No. 5,581,539. This proposes a method in which the track pitch of the file management area corresponding to the TOC portion or the FAT portion of the recording area of the optical disc is 1.05 to 1.5 times wider than other data recording areas. As a result, since the file management area is less than 1% of the entire area of the disc, the cross-eraser problem can be solved to some extent while maintaining high density. However, in the above method, if the number of repetitions continues to increase, the cross-erase phenomenon may appear to some extent.

Accordingly, it is an object of the present invention to provide an optical recording medium capable of preventing cross-talk and cross-laser phenomena which degrade information of adjacent tracks in a plurality of repeated recordings.

It is another object of the present invention to provide an optical recording medium recording method capable of preventing cross-talk and cross-laser phenomena which degrade information of adjacent tracks in a plurality of repeated recordings.

In order to achieve the above object, an optical recording medium according to the present invention, in an optical recording medium having a plurality of tracks, crosses a data recording area in which data is continuously recorded on the tracks, and one track among the tracks and the like. And a file management area in which data is recorded.

An optical recording medium according to the present invention is an optical recording medium having land- and groove-shaped tracks and includes a data recording area in which data is recorded in both land- and groove-shaped tracks, and among the tracks in the land- and groove-shaped shapes. It is characterized by including a file management area in which data is recorded only on either side.

Further, in order to achieve the above object, the optical recording medium recording method according to the present invention has a position where data is to be recorded in recording data on an optical recording medium having a plurality of tracks and divided into a data recording area and a file management area. A first step of identifying whether it is a data recording area or a file management area, a second step of continuously recording data on the tracks when it is determined as a data recording area in step 1, and a file management area in step 1 And recording a data by skipping one track among the tracks.

The optical recording medium recording method according to the present invention has a land-shaped and groove-shaped track and records the data in an optical recording medium divided into a data recording area and a file management area. A first step of identifying whether or not it is a file management area; a second step of recording data for both land-shaped and groove-shaped tracks when the data recording area is determined in step 1; and a file management area in step 1 And recording the data only on either one of the land-shaped and groove-shaped tracks.

The above and other objects and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention.

Hereinafter, the most preferred embodiment of the present invention will be described with reference to the accompanying drawings.

First, the optical recording medium applied to the present invention will be described with reference to a phase change type optical disk having a general structure as shown in FIG. Looking at the structure of the optical disk in more detail as follows.

The phase change type optical disk shown in FIG. 1 has a lower dielectric layer 2, a recording layer 3, an upper dielectric layer 4, a reflective film layer 5, and an ultraviolet protective film layer continuously stacked on top of the transparent substrate 1. It consists of (6).

In the phase change type optical disk, a transparent substrate 1 having a predetermined thickness is usually used for all transparent plastic substrates, for example, polycarbonate or PMMA substrates, and although not shown, they usually have land and groove surfaces. The lower and upper dielectric layers 2 and 4 stacked on the transparent substrate 1 with a uniform thickness are all commonly used dielectric materials having low absorption in operating wavelengths, such as ZnS-SiO ₂ , SiO ₂ , and the like. AIN etc. are possible. As the information recording layer 3 formed between the lower dielectric layer 2 and the upper dielectric layer 4, all phase-changeable materials that can be repeatedly recorded may be used. Representative examples thereof include Ge-Sb-Te and Ag-In. -Sb-Te system is mentioned. The reflective film 5 stacked on the upper dielectric layer 4 may be any metal reflective film generally used. Examples of the reflective film 5 may include Al-Ti (%) alloy and Au.

The manufacturing method of such a phase change type optical disk will be briefly described as an example. First, the lower dielectric layer 2 is formed on the polycarbonate substrate 1 and sputtered at high frequency (RF) to form a dielectric film having a thickness of 80 to 150 nm. Subsequently, the target of the information recording layer 3 satisfying the above composition formula is changed to a pressure of 1-5 mtorr and a power of 100-300 W to be sputtered and uniformly laminated on the lower dielectric layer 2 so as to have a thickness of 15 to 30 nm. . Thereafter, the upper dielectric layer 4 is formed to a thickness of 20 to 50 nm on the information recording layer 3 by sputtering at a high frequency like the lower dielectric layer. The reflective film 5 of the aluminum alloy is formed by laminating a thickness of 80 to 150 nm on the upper dielectric layer 4, and then the ultraviolet curable resin is applied to form the protective layer 6.

2 is a diagram showing in detail the information recording surface of the optical recording medium according to the present invention.

Referring to FIG. 2, there is shown an optical disc having an information recording surface 7 on which a land track 8 and a groove track 9 are formed on a transparent substrate 1 having lands and grand surfaces. This optical disc is divided into a file management area corresponding to a FAT portion in the DOS format and a TOC portion in the CD format and a data recording area for recording the user's data with the dotted line shown in FIG. Here, the file management area forms the recording pits 10 only on the land track 8 or the groove track 9. That is, the file management area makes land-only recording or groove-only recording to widen the distance between tracks on which data is recorded. As a result, it is possible to prevent thermal influences on the data of the adjacent tracks even during a plurality of repeated recordings. On the other hand, in the data recording area in which the user's data is recorded, the recording pits 10 are formed on all of the land track 8 and the groove track 9. That is, the data recording area can perform high density recording because land and groove recording is performed conventionally.

The information recording method according to the present invention in the above optical disc is as follows.

First, the optical disc is premised on that an auxiliary signal indicating the storage area of the optical disc, i.e., the physical position of the track, is formatted. This auxiliary signal is preformatted in the form of a wobble signal on the optical disk. In other words, the auxiliary information of this wobble signal type is preformatted by the wobble of the land and groove tracks, so that the user does not consume the track area in which data is to be recorded.

Accordingly, in the case where information is recorded on the optical disc, it is determined in the first step whether the portion to record the information is a data recording area or a file management portion by using an Absolute Time In Pregroove (ATIP) signal. Since the position signal of the disk is included in the ATIP signal, it is possible to distinguish the data recording area from the file management area. In addition, the data recording area and the file management area can be distinguished by using a pre-embossed pit. At this time, the position signal of the disc may be inserted into the pre-embossed pit to distinguish between the file management area and the data recording area.

When it is determined that the data recording area is part of the first step, land and groove recording is performed in the second step. If it is determined that the file management area is part of the first step, groove-only or land-only recording is performed in the third step. At this time, only groove recording may be performed for better signal quality.

Accordingly, by performing land-only recording or groove-only recording on the file management area of the optical disc, the distance between the tracks on which data is recorded can be widened, thereby preventing the occurrence of the cross-erase phenomenon. In addition, cross-talk phenomenon can be prevented from occurring even when reading data recorded on the optical disc.

As described above, according to the present invention, the file management area of the optical disc is used for land-only recording or groove-only recording to widen the distance between the data recording operations, thereby making cross-erasers due to thermal effects on adjacent tracks during repeated recording. The phenomenon can be prevented from occurring. In addition, it is also possible to prevent the occurrence of a cross-talk phenomenon due to a thermal effect on adjacent tracks when reading data recorded on the optical disc. The data recording area in which actual data is recorded records land and grooves, and the file management area occupies less than 1% of the disk, so that the optical disk as a whole can maintain high density recording.

On the other hand, in the embodiment of the present invention has been described as limited to the optical disk having a land shape and groove shape, it will be appreciated by those skilled in the art that any optical disk having a plurality of tracks can be applied by extending it.

Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (7)

In an optical recording medium having a plurality of tracks, A data recording area in which data is continuously recorded on the tracks; And a file management area in which data is recorded by skipping one track of the tracks. An optical recording medium having tracks in the form of lands and grooves, A data recording area in which data is recorded in both the land-shaped and groove-shaped tracks; And a file management area in which data is recorded only on any one of said land-shaped and groove-shaped tracks. The method of claim 2, The file management area is And data is recorded only in the tracks of the land shape. The method of claim 2, The file management area is And data is recorded only in the groove-shaped track. The method of claim 2, And the position signal of the track is preformatted in the form of a wobble signal by the wobble of the land- and groove-shaped tracks. In recording data on an optical recording medium having a plurality of tracks and divided into a data recording area and a file management area, A first step of identifying whether the position at which the data is to be recorded is a data recording area or a file management area; A second step of continuously recording data in the tracks when it is determined as the data recording area in the first step; And recording the data by skipping one track among the tracks when it is determined as the file management area in the first step. In recording data on an optical recording medium having tracks of land shape and groove shape and divided into a data recording area and a file management area, A first step of identifying whether the position at which the data is to be recorded is a data recording area or a file management area; A second step of recording data for both land-shaped and groove-shaped tracks when the data recording area is determined in the first step; And a third step of recording data only on either one of the land-shaped and groove-shaped tracks when the file management area is determined in the first step.