JPH0421944A - Optical recording medium - Google Patents

Abstract

PURPOSE:To decrease a recording area capacity by recording two kinds of light intensities for recording on control tracks when identification information indicates direct overwriting optical modulation recording and the light intensities for recording and reproducing in other cases. CONSTITUTION:The magneto-optical disk 1 has 1st, 2nd magnetic layers 12, 13 on a substrate 11 which are magnetized upward. The layer 12 allows the direct overwriting of the information 1, 0 by an external magnetic field+H and a light beam LB of high and low outputs PH, PL. The outputs PH, PL are recorded as recording conditions in the standard format parts SFP1 to SFPn of the control tracks CT. The identification information to indicate whether the direct overwriting optical modulation type or not and the information for reading the SFT1 to (n) are recorded in phase modulation parts PEP1 to 3. The optical recording medium driving device accesses user data areas UA1 to (n) with the outputs suited to the respective conditions after first identifying the type of the optical recording medium from the identification information of the PEP1 to 3. The capacity of the area of the CT to record such information is decreased in this way.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to optical recording media such as optical discs, magneto-optical discs, and phase change optical discs that comply with ISO standards, and in particular, to optical recording media that are capable of wide left overwriting by optical modulation. The present invention relates to an optical recording medium including:

[Conventional technology]

A 130-fi optical disc, which is standardized by ISO, has areas called control tracks on its inner and outer peripheries. The radius of the inner control track is 29~
29.5 There is a phase modulation section in the annular part between the dragons.
A region called d flncoded part (hereinafter referred to as PEP) is also standard in the annular part between the radius of 29.52 and 29.71 m and between 60 and 15 and 60.5 mm of the inner and outer control tracks. S Landard Format
A region called "art" (hereinafter referred to as SFr') is provided. The PEP has no track grooves, and unlike the user area, information is recorded at a low density. This is to reproduce media with various characteristics without errors. P
The type of optical disc and information for reading the SFP are recorded in the EP using phase codes whose phases are inverted. PEP consists of a set of 18 bytes from byte 0 to byte 17, and three sets are recorded in one round. The format of the optical disc is recorded in the upper four bits of byte 7 of the PEP, and when bit 5 is "1", it indicates that it is a write-once type.

The SFP has a track groove in which various conditions for recording and reproducing the optical disc at the same density as the user area are recorded. The SFP has a total area of 512 bytes, of which 18 hides from bytes O to 17 contain PEP replication information, 366 heights from bytes 18 to 383 contain media information such as optical disc recording and playback conditions, and bytes 384
System information such as the number of bytes of the user area is recorded in 64 bytes from 447 to 447.

Furthermore, bytes 448 to 511 are reserved areas for future standardization or standards other than this standard.

In the area of the SFP where media information is recorded, conditions for reflectance and light intensity are defined for three types of laser wavelengths.

Regarding the light intensity, four types of disk rotation speeds are specified for each wavelength, and a total of 12 types of light intensity are specified. Furthermore, for each of the 12 conditions,
In the case of the constant pulse width method, 9 types of light intensity with 3 types of recording radius and 3 types of pulse width are specified, and in the case of the constant power type, 4 types of conditions are specified: light intensity and pulse with 3 types of radius. A total of 13 conditions are defined. Therefore, a very large amount of light intensity condition data of 13×12 (156) types is recorded with each type being one byte.

Similarly, in the media information area of the SFP, condition data for erasing is stored in the same number of bytes as for recording, so a total of 312 bytes of condition data related to light intensity is stored. .

Recently, rewritable optical disks, such as magneto-optical disks, have been proposed that allow direct overwriting with one beam by optical modulation or magnetic field modulation. This was developed to eliminate rotational waiting time during erasing of magneto-optical disks and to increase access speed. A magnetic field modulation type device forcibly determines the direction of magnetization in accordance with a binary signal, similar to a magnetic disk device, and requires only one type of light intensity during recording. - The force tip modulation type has a plurality of magnetic layers formed on a magneto-optical disk, and changes two types of light, strong and weak, in accordance with a binary signal during recording.

In addition, a phase change type optical disk has also been proposed in which direct override is possible with one beam by optical modulation using two types of light, strong and weak, in accordance with a binary signal.

[Problem to be solved by the invention]

The above-mentioned optical disc that can be directly overridden by optical modulation is still in the development stage and has not been standardized by ISO, but if it were to be standardized, there would be two levels of light intensity, high and low, so if it were applied to the above-mentioned standard, 15 more
Six combinations are required, totaling 1 including elimination.
56 x 3 = 468 combinations are required. Therefore, there is a problem that 468 bytes are required to store the condition data, and the condition data cannot be stored in the 366-byte media information area of the ISO standard.

This is currently being standardized by ISO90.
The same is true for the mm optical disc, and although the area that defines the light intensity within the control track is not determined, there is no room to store three types of condition data.

The present invention has been made in view of such circumstances, and it records whether or not light modulation recording is performed on the PEP in the control track as identification information, and the SFP in the control track
To provide an optical recording medium capable of recording light intensities in a recording area of the same capacity regardless of whether overwriting by optical modulation is possible or not by recording two types of light intensities based on identification information.

[Means to solve the problem]

In the optical recording medium according to the present invention, identification information indicating whether or not optical modulation recording is performed is recorded in the control track portion, and if the optical recording medium is not optical modulation recording, the respective light intensities used for recording and erasing are adjusted according to the identification information. In the case of optical modulation recording, two levels of light intensity (high and low) used for recording are recorded.

[Effect]

In the present invention, identification information indicating whether or not light modulation recording is being recorded is recorded in the control track portion, and if it is not light modulation recording, the respective light intensities for recording and erasing are recorded, and the light intensity of each light modulation recording is recorded. In this case, since two levels of light intensity, high and low, are recorded for overwrite recording, the data capacity of the light intensity is the same regardless of whether or not the light modulation recording allows wide left overwriting.

In the case of optical modulation recording, a wide left overwrite is possible, so when erasing data, predetermined data can be recorded using a wide left overwrite. Therefore, the light intensity for erasing is not necessary, and the light intensity of one of the two levels can be written in the area where the light intensity for erasing is recorded.

〔Example〕

The present invention will be described below based on drawings showing embodiments thereof.

FIG. 1 is a plan view showing the area configuration of a 130 n+ magneto-optical disk, which is an optical recording medium according to the present invention. In the figure, reference numeral 1 denotes a magneto-optical disk, and this magneto-optical disk 1 has a two-layer film structure that allows for wide left overwriting by optical modulation. Control tracks CT on which control information is recorded are provided on the inner and outer peripheries of the magneto-optical disk 1. Radius of inner control track CT 29
In the annular region of ~29.5 mm three phase modulation sections PEPI of 18 byte length.

PEP2. PEP3 is preformatted.

The phase modulation units PEPI to PEP3 have no trunk grooves, and information is preformatted in triple writing using phase codes.

Identification information indicating the format of the medium, such as whether it is a wide left overwrite light modulation type, and information for reading a standard formant part to be described later, are recorded here. For details, see IS.
O/TECDIS 10089, page 42, 16.4.3
．． Although the description is omitted, byte 7 records the type of medium. For example, in the case of a wide left overwrite light modulation type, a predetermined bit (for example, The most significant bit) is 1''.

Also, the phase modulation section PEPI of the control track CT
In the annular area with a radius of 29.52 to 29.70 am following PEP3, there is a standard format part SFP for each sector,
~SFP.

(n: number of sectors) is preformatted, and recording and playback conditions, etc. are recorded therein in a standard user data format. Here, a sector is a track divided equally in the inner circumferential direction; for example, in ISO, the number of sectors n is 1.
7 or 31, and when the number of sectors is 17, the user data area of l sector is 1024 bytes, and when it is 31, it is 512 bytes. Each standard format section SFP1 to SFP stores 512 bytes of data from bytes O to 511, and the contents of phase modulation sections PEPI to PEP3 are copied from bytes 0 to 17, and 342 bytes from bytes 18 to 359 are stored. The bite has 3 types of combinations of wavelength and reflectance, 4 types of rotation speed (N, ~Nt), 3 types of radius (30 mm, 45 mm, 60 mm), and 3 types of pulse width (T Xl, 0, TXo, 5, TXo, 25)
Information including two types of values of recording power (light intensity) for each is included.

Table 1 shows the wavelength L11 and reflectance R1 of a light modulation type optical recording medium.
2 is a table showing the stored bytes of the standard formant section when the number of rotations is N+ and the reproduction power is P1.

(Left below) In other words, recording conditions 1.2 such as two types of recording power with different light intensities, high and low, are recorded in 26 bytes from Hyde 22 to Hyde 47, and on the other hand, three wavelengths and four rotation speeds are recorded. There are 12 ways, 104 bytes for each type of wavelength, a total of 31
The recording capacity is 2 bytes.

On the other hand, in the non-light modulation type, erasing power is recorded instead of the second recording power. This is ISO/IECD
It is as described in Table 2 on page 50 of IS 10089, and the explanation is omitted.

An annular t43'A with a radius of 30 to 60W following the standard format part spp, ~SFP, , is an n-sector user data area tlA, ~UA, and is a recording area that can be left overwritable using a two-layer film, which will be described later. It has become an area.

and the radius of the outer control track CT is 60.1
The annular area of 5 to 60.5 ml is provided with standard format sections SFP and 5FP11 having the same content as the standard format portions 5FPI to 5FPn provided on the inner circumferential side.

FIG. 2 is a conceptual diagram of the recording operation in user data areas UA+ to IIA.

The magneto-optical disk 1 includes, on a substrate 11 made of glass, for example, a first magnetic layer 2 having perpendicular magnetic anisotropy and whose magnetization direction can be reversed, and a first magnetic layer 2 having perpendicular magnetic anisotropy on the first magnetic layer 1if12. The second magnetic layer 11513 is magnetized in one direction and whose magnetization direction cannot be reversed under the same conditions as the first magnetic layer 12. The second magnetic layer 3 of the magneto-optical disk 1 shown in FIG. 2 (bl) is magnetized in the opposite direction to the substrate 11, that is, upward.

Next, the operation when overwriting information on these magneto-optical disks 1 will be explained.

First, recording signals of 1" and "o" shown in FIG. 2(a) are recorded on the magneto-optical disk 1 in which the magnetization direction of the second magnetic layer 13 is in the opposite direction to the substrate 11 as shown in FIG. 2(bl). When overwriting information using PD, magneto-optical disk 1
is rotated, and a downward external magnetic field H is applied as shown by the black arrow in the direction opposite to the magnetization direction of the second magnetism 1i13. In the period when the recorded signal is “work”, Figure 2 (C
As shown in FIG. 1, a light beam LB of high output Pl+ in the projection direction indicated by the white arrow is projected onto the first outer magnetic layer 12. When the first magnetic layer 12 is heated by the light beam LB and reaches the Curie temperature, the magnetization direction of the first magnetic layer 12 is changed by the external magnetic field 1H.
, that is, in the direction of the substrate 11, and the magneto-optical disk 1
When the light beam LB is no longer projected due to the rotation of the first magnetic layer 12 and the temperature of the first magnetic layer 12 decreases, the first magnetic layer 12
It is magnetized in the direction of , and records information "1". Further, during the period when the recording signal is "o", a light beam LB with a low output P is projected onto the first magnetic layer 2 as shown in FIG. 2 (C1).

As a result, the coercive force of the first magnetic layer 12 is reduced, and the first magnetic layer 12 is magnetized in the same direction as the second magnetic layer 13, that is, magnetized in the opposite direction to the substrate 11, thereby recording information "0".

This makes it possible to perform a wide left overwrite regardless of what information has been previously recorded.

Then, the recording power of these two high and low levels of output P, , Pt is set as recording conditions 1 and 2 in the standard format section 5F.
Recorded in PI-5FPIl.

In addition, in the case of optical discs that are recorded using the output of the Rubel, IS
The storage bytes are as shown in Table 2 on page 50 of O/IECDis 10089, and the erase condition is written in the second recording power column, and the phase modulation unit PEPI
- Information indicating this (for example, the most significant bit - "0") is recorded in byte 7 of PEP3.

By recording such a formant on an optical recording medium, the optical recording medium drive device that accesses it first identifies the format of the optical recording medium based on the information of the phase modulation units PEPI to PEP3, and performs direct override. In the case of an optical recording medium that allows light modulation, read the recording conditions 1.2, and in the case of an optical recording medium that does not, read the recording conditions and erasing conditions, and output the user data area with an output that meets each condition. A,-UAll is accessed.

In this embodiment, a two-layer film 130-layer magneto-optical disk is used as an example of the optical recording medium, but the present invention is not limited to this, and may be applied to a multi-layer film magneto-optical disk such as a three-layer film or a 4N film. It goes without saying that the present invention can also be applied to other optical modulation type optical recording media such as phase change optical disks.

〔Effect of the invention〕

As explained above, in the present invention, the identification information indicating whether direct overwriting light modulation recording is used is used to select two types of light intensities used for recording in the case of light modulation recording, and for recording and reproduction in other cases. By recording the light intensities to be used in the control track section, an equivalent effect can be achieved in which the capacity of the area for recording them can be reduced.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the area configuration of a magneto-optical disk with a two-layer film structure, which is an optical recording medium according to the present invention, and FIG. 2 is a conceptual diagram of a recording operation in a user data area. 1... Magneto-optical disk CT... Control track PEPI to PEP3... Phase modulation section SFP,
-SFP, . . . Standard format section In the figures, the same reference numerals indicate the same or equivalent parts. Agent Masu Oiwa, Date 2, Name of the invention Optical recording medium 3, Representative Moriya Shiki 5, ``Claims'' and ``Detailed description of the invention'' of the specification to be amended. ”
Column 6, Contents of amendment 6-1 As per the separate sheet of "Claims" of the specification 6-2 Column of "Detailed description of the invention" of the specification fil Page 2 of the specification Nos. 17-18 Delete the line that says "phase was inverted." (2) In the first line of page 4 of the specification, it is stated that “9 pulse widths are available in 3 different ways”.
Correct the phrase "3 different pulse widths, 9 different pulse widths in total". (3) "4 types of pulses" on page 4, line 3 of the specification
Correct the statement to read "4 types of pulses in total." (4) On page 4, line 4 of the specification, the statement "13 types in total" should be corrected to "13 types in total." (5) "Light modulation recording" on page 6, line 4 of the specification is corrected to "direct overwriting light modulation recording j.""Recording" has been corrected to "Direct overwriting optical modulation recording." (7) On page 6, line 13 of the specification, the phrase "light modulation recording" is corrected to "direct overwriting light modulation recording." (8) In the 14th line of page 6 of the specification, the phrase ``recorded'' is corrected to ``recorded as two types of light intensities of medium information'' in the specification. (9) In the 15th line of page 6 of the specification, the phrase "recorded in the case of optical modulation recording" is corrected to "in the case of direct overwrite optical modulation recording, the medium information is recorded as two types of light intensities." . 00) On page 6, lines 18-19 of the specification, the phrase ``single light modulation recording'' is corrected to read ``direct overwriting light modulation recording.'' (1υ In the 20th line of page 6 of the specification, the phrase ``Recorded if not optical modulation recording'' has been changed to ``If not direct overwrite optical modulated recording, record medium information as two types of light intensities.'' 0no In the first line of page 7 of the specification, "light modulation recording" is corrected to "direct overwriting optical modulation recording." 031 In the second line of page 7 of the specification, "light modulation recording" is corrected. 04) In the 3rd line of page 7 of the specification, the phrase ``gray left overwritable'' should be changed to ``overwrite recording as two types of light intensities for medium information''. Can be directly overwritten.'' 0 Clause In the 4th line of page 7 of the specification, the phrase ``regardless of the light intensity'' is changed to ``regardless of the light intensity, two types of light intensities are recorded.''
I am corrected. 06) Delete "(for example, the most significant bit)" from lines 13 to 14 on page 8 of the specification. 07) In the first line of page 9 of the specification, "inner circumferential direction" is corrected to "circumferential direction." Q8) Delete the statement "(For example, the most significant bit = "0")" in the fourth line of page 14 of the specification. 7. List of attached documents (1) A document stating the entire text of the amended scope of claims 2. Identification of the media information including claims (1)-4 Tax 11 mutual exchange j 1 branch and its format In an optical recording medium having a control track section on which identification information is recorded, the control track section has an indicator indicating whether or not direct overwriting optical modulation recording is to be performed on the control track section at a light intensity of 21 levels high and low. If identification information is recorded and the identification information indicates that the recording is not directly overwritten optical modulation recording, the respective light intensities used for recording and erasing are recorded as -2, and the identification information 2. An optical recording medium characterized in that, when indicates direct overwriting optical modulation recording, a light intensity of the 21-level used for direct overwriting recording is recorded as 2 of MMI.

Claims (1)

[Claims] (1) In an optical recording medium having a control track section on which medium information including recording conditions and identification information for identifying the format are recorded, the control track section is provided with two levels of light, high and low. If identification information indicating whether or not direct overwriting optical modulation recording is performed by intensity is recorded, and the identification information indicates that direct overwriting optical modulation recording is not performed, the respective optical intensities used for recording and erasing. is recorded, and when the identification information indicates that it is a direct overwrite optical modulation recording, the optical recording medium is characterized in that the two levels of light intensity used for direct overwrite recording are recorded. .