KR100229369B1 - Magneto-optical disc recording medium - Google Patents

Abstract

The present invention relates to a magneto-optical disc recording medium, and more particularly, to find an incomplete and optimal recording condition of a recording caused by different recording conditions in each zone by a zoned constant angular velocity (ZCAV) format. The present invention relates to a magneto-optical recording medium that improves the performance of an entire recording system by providing a drive with an optimal recording condition by pre-pits in order to reduce the delay of time caused by a plurality of recording and reproducing tests.

Description

Magneto-optical recording media

1 is a graph showing a recording pulse pattern used in recording by a general mark edge method.

The present invention relates to a magneto-optical disc recording medium, and more particularly, to find an incomplete and optimal recording condition of a recording caused by different recording conditions in each zone according to a zoned constant angular velocity (ACAV) format. The present invention relates to a magneto-optical recording medium that improves the performance of the entire system by providing the drive with an optimal recording condition by pre-pits in order to reduce the time lag caused by a plurality of recording and reproducing tests.

In the recent development of magneto-optical disks, high data transfer speeds and high density have been the subjects, and studies have been actively conducted in various parts of the world. In particular, in order to achieve a high density of disk capacity, the wavelength of the laser light must be shortened, and the recording angle must be excellent due to the large rotation angle at a short wavelength. The recording principle of the magneto-optical disk records information by changing the direction of the perpendicular magnetism in the magnetic domain by scanning a laser beam on a thin film material having a perpendicular magnetism, and rotating the recorded information in the polarization direction (Kerr effect). This is the principle of reading using.

Such a magneto-optical recording medium must satisfy the following characteristics in order to obtain a good effect.

First, the recording density of the information storage must be high, and there must be sufficient perpendicular magnetic anisotropy to take advantage of the kerr effect of the polarizing beam in reading the information,

Second, since the signal is large and proportional to the angle of rotation, the angle of rotation must be large,

Thirdly, it should have a low Curie temperature (Tc) of generally 300 ° C or less, so that information can be recorded at low power, typically less than 200mW laser diode output,

Fourth, the coercivity should be 1k0e or more so that the recorded magnetic domain is not erased by the external magnetic field,

Fifth, the life of the product should be long, because the oxidation and corrosion resistance of the material is strong,

Sixth, performance should be comparable to that of conventional storage media (hard disks, etc.).

At present, recording and reproducing of a magneto-optical recording medium takes a lot of time during recording because the recording and testing are performed several times between a zone and a zone of a user data area formed on the disc to obtain an optimal recording condition. Incomplete recording by interpolation of recording conditions given in a standard formatted part (SFP) becomes a problem. At this time, the SFP has a basic physical format such as the size of a sector, the number of sectors and the number of tracks, basic characteristics such as reflectance and performance index, and various conditions such as recording conditions, erasing conditions, playback conditions, wavelengths, and rotation speeds. The above information is provided to the drive when the disc is mounted as an area created by the disk.

Since the conventional magneto-optical disc is recorded by a simple pit position method, there is no problem with the recorded magnetic field or the reproduction signal. However, in the recording method of the magneto-optical disk, which is three times as large as the existing capacity, the mark-edge method is used instead of the pit position method, which makes it difficult to form a recording domain. It tries to make recording domain uniform by using the same method as writing compensation. In the case of 130mm discs, the recording frequency is different for each zone because the zones are divided in ZCAV format in physical format to increase capacity. As a result, various recording conditions have been changed, and incomplete recording (increasing jitter) and recording during recording by using the recording conditions of the SFP or by repeatedly recording and playing on the test track between zones to find these conditions. There was a problem that it takes a lot of time, and also, since the user data area is divided into several zones by the ZCAV method, there is a problem that recording in each zone becomes difficult. In addition, even when the recording conditions of the SFP area are not used, there is a problem in that recording takes a long time because the optimum condition is found by recording and replaying a plurality of times in the test track of each zone.

Accordingly, an object of the present invention is to provide a magneto-optical disc recording medium capable of stable recording and high-speed recording regardless of the area by providing an optimal recording condition in advance by a prepit in the user date area in order to solve the above problems. To provide.

The magneto-optical disc of the present invention for achieving the above object has a structure of a user area of a disc, which includes (A) a buffer area, (B) a zone information sector area, and (C) data. ) Disk, (D) parity area, (E) spare area, and (F) buffer area.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

Table 1 below shows the format structure of a conventional magneto-optical disk user area.

TABLE 1

The defect management area (DMA) is composed of a disk definition structure (DDS), a primary defect list (PDL), and a secondary defect list (SDL), and the DDS is a type of disk, a track and sector where the PDL starts, and an SDL starts. Information such as track and sector number are stored.In the PDL, defect sector information of the disc is input before the user uses it.In the SDL, if a defect sector is generated when the user uses the disc, the spare area is replaced and recorded and used. The address of the spare area is stored.

(a) The buffer area is a buffer area provided to designate a certain number of tracks between the areas so as not to affect other data areas during recording. (b) The data area is a space where information is stored. The parity area corrects when a playback error occurs in the ROM sector in the case of a ROM type disc such as an O-ROM, P-ROM, or P-ROM-R. (E) Buffer area plays the same role as buffer (a), and (f) Test area is a recording and playback test to find the optimal recording condition before recording data in each band. (G) The buffer area also performs the same function as the buffer areas (a) and (e). In this case, in the case of a ZCAV type magneto-optical disk, the band is designated as a data area having a constant angular velocity.

Table 2 shows the format structure of the magneto-optical disk user area according to the present invention.

TABLE 2

(A) Buffer area, (B) Zone information sector area, (C) Data area, (D) Parity area, (E) Spare area, (F) Buffer area, where (A) buffer area, (C) data area, (D) parity area, (E) spare area, and (F) buffer area are the same as the conventional functions. By specifying the information sector area between (A) buffer area and (C) data area, the roles of the conventional (g) test area and (f) buffer area are replaced as shown in Table 1 below.

TABLE 3

Where r represents the radius of the disk.

Therefore, the magneto-optical recording medium of the present invention is characterized by designating an information sector area between (A) buffer area and (C) data area so as to replace the conventional (f) test area and (s) buffer area thereof. The data of this information sector area is shown in Table 4 below.

TABLE 4

Here, the value of P1, which is the content of bytes 5-7, is the recording power of the initial pulse, P2 is the bias power, P3 is the power between pulse trains to make the recording domain uniform, and P4 is The recording power of the pulse train is shown, t1, which is the content of byte 8-9, is the recording time of the first pulse, t2 is the recording time of the pulse train, and t3 is the time between the pulse trains.

As shown in Table 4, the bytes forming the information sector area according to the present invention are 1024 bytes in total, and only 1 to 14 bytes are used, and 15 to 1024 bytes are not used. 1 byte is the first data track of this area, that is, the information sector area, 2 bytes the last data track, 3 bytes the recording frequency, 4-10 bytes the recording power and the recording duty, and 11 bytes the starting track of the spare area. , 12 bytes designate the end track of the spare area.

Meanwhile, the format of Table 1, which is a conventional inventor, includes various types of information such as regeneration power, erase power, and performance index for each rotational speed or wavelength. However, since such information is input to the drive in advance, Table 4 according to the present invention is used. By specifying the same information, effective recording and reproducing are possible.

In addition, Table 2, which is the format structure of the user area of the disk according to the present invention, shows that the optimum recording conditions such as the recording power and the recording duty indicating the characteristics of each zone in advance by measuring the characteristics of the disk in advance are physically free. It is input in the form of a pit in advance at the time of manufacture of the stamper, and during recording and reproducing, information is recorded and reproduced in the data area according to the recording conditions as shown in Table 4 without performing the recording and reproducing test several times unlike in the prior art.

Therefore, since the test area (4 tracks) and its buffer area (4 tracks) are not required in the conventional user area structure, the use capacity of 8 tracks per zone is increased, and information stored in the information sector area is read in advance during recording and playback. Recording and playback reduces recording and playback time.

Hereinafter, the effects of the present invention will be described in more detail through Example 1 and Comparative Example 1, but the scope of the present invention is not limited to the following examples.

Example 1

A substrate made of polycarbonate was injection molded using a stamper having the format shown in Table 2. The magneto-optical disk having the format as shown in Table 2 was produced by sputtering using an alloy target of TbFeCo on it. The manufacturing conditions of the thin film were the initial vacuum degree of about 3 × 10 ⁷ mbar, the Ar gas pressure of about 3 mtorr, the Ar gas flow rate of 50 SCCM, the DC power of 1.0 kw, and the distance between the target and the substrate to about 64 mm. Silver was prepared by the DC sputtering method, and the protective film was made of Si ₃ N ₄ having a refractive index of about 2.01 with a flow rate of Ar and N ₂ gas at 1: 1. The fabricated specimens were fabricated on a polycarbonate substrate with a protective film of 200Å, a recording film of 200Å, and a reflective film of 300Å.

Comparative Example 1

A magneto-optical disk was manufactured in the same manner as in the above example except that a stamper having a conventional ZCAV format as shown in Table 1 was used.

Thus, the magneto-optical disks prepared in Comparative Example 1 and Example 1 were rotated: 3000 rpm, recording pulse duty (1T): 20 ns to 39.4 ns, recording power: variable, erase power: variable, reproduction power. The jitter values were measured at 1.5 mW and the external magnetic field at 300 Oe.

All the recording conditions in the information sector represent P ₁ , ₂ , ₃ , ₄ and t ₁ , ₂ , ₃ values of the recording pulses as shown in FIG. ₁ .

As can be seen from Table 5, as a result of recording and reproducing in several zones, as shown in the table, when recording and reproducing by using interpolation using conventional SFP data, the 2T and 4T marks have small jitter but jitter in long periods of 5T to 8T. It can be seen that increases. However, as shown in Table 6, when the recording conditions of the zone were directly read and recorded in the information sector area, very small jitter values of 4 ns or less were obtained in the 2T to 8T recording patterns. In addition, when SFP data is not used as shown in Table 6, when only the P1 value in FIG. 1 is changed, much more time is recorded than in the case of Table 2 because recording and replaying are required several times in the test track of each zone. Is needed. Therefore, if you change P2, P3, P4, t1, t1, t3, there will be more time difference.

Therefore, in the magneto-optical recording medium according to the present invention, an information sector area is created in a user area of a ZCAV format, and various recording conditions are inputted in advance to this information sector area so that the recording condition of each zone is read and jittered at the optimal condition. Has the effect of reducing a very small complete recording and recording time, and also has the effect of increasing the information storage space of the disc by deleting the conventional test area and its buffer area.

TABLE 6

TABLE 7

Claims (5)

In the structure of the magneto-optical disk user area using the mark edge recording method and the ZCAV format, (A) buffer area, (B) zone information sector area, (C) data area, ( D) A magneto-optical recording medium having a structure of a user area of a disc composed of a parity area, an (E) spare area, and an (F) buffer area. The magneto-optical recording medium according to claim 1, wherein (B) all recording conditions corresponding to each zone in the information sector area are physical prepits. 2. The information sector according to claim 1, wherein the (B) information sector area includes a first data track, a last data track, a recording frequency, a recording power, a recording time, a start track of a spare area, an end track of a spare area, a start track of a buffer area, and a buffer. Magneto-optical recording medium, characterized in that consisting of bytes for storing information about the end track of the area. The magneto-optical recording medium according to claim 1 or 3, wherein the information storage bytes for the recording power and the recording time are designated as four recording powers and three recording times. 4. The information storage byte according to claim 1 or 3, wherein the first data track, the last data track, the recording frequency, the start track of the spare area, the end track of the spare area, the start track of the buffer area, and the end track of the buffer area. Magneto-optical recording medium, characterized in that each one is specified.