JP2745713B2 - Information recording method, information reproducing method and recording medium - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording method, an information reproducing method, and a recording medium, and more particularly, to main information recorded in a track direction on a pre-formed recording track. The present invention relates to a recording medium on which another read-only information is recorded and formed by a displacement in a track width direction, an information recording method for the recording medium, and an information reproducing method.

B. Summary of the Invention The present invention is an information recording method for recording main information along a track direction on a recording track formed in advance,
By using a recording medium on which read-only information is pre-recorded and formed on the recording track by displacement in the track width direction and by recording main information in the same recording method as the recording method of the read-only information, the circuit configuration can be shared. In an information reproducing method for reproducing main information recorded along a track direction on a recording track formed in advance on a recording medium, reproduction-only information is preliminarily recorded on the recording track by displacement in a track width direction. By using a recording medium and reproducing the main information by the same reproduction method as that of the reproduction-only information, the reproduction circuit itself can be shared. Further, in a recording medium on which main information is recorded along a track direction on a pre-formed recording track, read-only information is pre-recorded on the recording track by a displacement in the track width direction by the same recording method as the main information recording method. By being formed, the recording / reproducing circuit configuration can be shared.

C. Prior Art In a recording medium capable of recording information, for example, a magneto-optical disk, a guide groove for tracking is previously formed in a spiral or concentric shape on the disk, and the guide groove formed in advance (a so-called guide groove) is formed. It is known that information is recorded and reproduced using the magneto-optical effect on the recording track along the track direction using a pre-groove) or a land portion between the grooves as a recording track. This is to record and reproduce information magneto-optically while optically detecting the guide groove and applying tracking servo.

In this case, control information such as a synchronization signal and an address and data are alternately recorded on a recording track,
It is known to perform data management or the like based on the control information, and the control information records and reproduces data in block units or frame units.

By the way, if playback-only data such as an operating system or a basic dictionary can be supplied in a form prerecorded on the recordable medium, it is convenient in terms of software supply from the manufacturer side and use on the user side. At the same time as information can be recorded, recording media such as disks and cards in which read-only information (ROM information) has been written in advance have been proposed and developed.

FIG. 4 shows an example of a magneto-optical disk as a recording medium on which such read-only data is recorded in advance. In FIG. 4, the magneto-optical disk 1 is provided with a so-called RAM area 2 in which signals can be recorded and a so-called ROM area 3 dedicated to reproduction. In the RAM area 2, a land portion in a guide groove (pre-groove) formed in advance or between grooves is used as a recording track 4, and information is magneto-optically recorded on the recording track 4. The ROM area 3 is provided with a track 5 on which read-only information is recorded in advance in the form of pits (so-called preformat).

However, in such a magneto-optical disk 1, the recordable RAM area 2 and the read-only ROM area 3 are separated from each other, so that the information recordable capacity of the entire disk is reduced by the ROM area 3. Will be done.

The main information recorded in the RAM area 2 must include control information such as a synchronization signal and address information for facilitating access during recording / reproduction. For example, a so-called CD
In the case of a format in which frame synchronization is performed every frame 588T (T is a channel bit cycle) according to the (compact disk) format, as shown in FIG.
A 24T synchronization signal portion including a pattern in which the 11T inversion interval is continuous twice, and a 14T subcoat portion via a 3T connection bit are provided at the head position of each frame, and a 3T connection bit is provided via a 3T connection bit. The remaining 544T is the original data (including parity and the like). Therefore, one frame of 58
44T of 8T cannot be used for original data recording, and the disk recording capacity is reduced accordingly.

Therefore, the present inventors have proposed a recording medium in which read-only information is recorded in advance by displacement in the track width direction, and a recording method and a reproduction method using this recording medium. According to this technique, it is possible to perform recording along a track direction such as magneto-optical recording on a track on which displacement recording is performed in the track width direction, so that the entire surface of the disk becomes a recordable area, and read-only information is recorded in advance. However, it is possible to prevent a decrease in the information recordable capacity.

D. Problems to be Solved by the Invention Incidentally, in such a magneto-optical disk, recording by displacement in the track width direction and recording along a track direction on a recording track can be performed independently of each other. Requires a circuit configuration for reproducing the data, and the configuration may be complicated. Also the so-called CD
Considering that various ICs (Integrated Circuits) and LSIs (Large Scale Integrated Circuits) that conform to the existing format such as the (Compact Disc) format are supplied to the market, these existing ICs and LSIs It is preferable to be able to effectively use the method in order to supply a recording / reproducing apparatus at low cost.

The present invention has been made in view of such circumstances, and can simplify a circuit configuration for recording / reproducing a recording medium on which read-only information is recorded in advance by displacement in a track width direction, and can use an existing format or the like. It is an object of the present invention to provide an information recording method, an information reproducing method, and a recording medium that can easily be used.

E. Means for Solving the Problems In order to solve the above-described problems, the information recording method according to the present invention records main information along a track direction on a recording track formed in advance on a recording medium. In the information recording method, the main information is recorded in the same recording system as the recording system of the read-only information, using a recording medium in which the read-only information is recorded and formed in advance in the recording track by displacement in the track width direction. .

In the information reproducing method according to the present invention, in the information reproducing method for reproducing main information recorded in a track direction on a recording track formed in advance on a recording medium, the reproduction-only information may have a track width. The above-mentioned problem is solved by using a recording medium pre-recorded and formed by directional displacement and reproducing the main information by the same reproduction method as that of the reproduction-only information.

Further, in the recording medium according to the present invention, in a recording medium in which main information is recorded along a track direction on a recording track formed in advance, reproduction is performed on the recording track by the same recording method as the main information recording method. The above-mentioned problem is solved because the dedicated information is recorded and formed in advance by displacement in the track width direction.

Here, the recording method refers to a modulation method, a demodulation method, a data format, an address format, and the like. The reproduction-only information includes control information such as a synchronization signal, a clock signal component, and address information, in addition to the original data such as a software program, dictionary data, audio data, and video data.

F. Function Since the recording method of the read-only information pre-recorded and formed by the displacement in the track width direction and the recording method of the main information are made the same, not only can the configuration of the reproduction circuit be mainly shared, but also the reproduction circuit itself can be used. It can be shared. Further, by making the recording method of the main information the same as the existing recording method, the existing circuit configuration can be used.

G. Examples Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 shows one embodiment of a recording medium according to the present invention.
For example, a magneto-optical disk 10 in which a perpendicular magnetization film having a magneto-optical effect is formed on a transparent substrate is schematically illustrated. A guide groove for tracking is formed in the magneto-optical disk 10 in advance in a spiral or concentric manner. A land portion within the preformed guide groove (pre-groove) or between the grooves is used as a recording track 11,
Main information is magneto-optically recorded on the recording track 11 along the track direction. This recording track
Reference numeral 11 indicates that read-only information is recorded and formed by displacement in the track width direction (displacement in the track width direction or modulation in the track width direction). The displacement information in the track width direction is extracted as a so-called high frequency component of a tracking error signal. The displacement frequency in the track width direction is sufficiently higher than the tracking error signal frequency, and has no adverse effect on the tracking error signal itself. It does not affect.

Here, the entire surface of the magneto-optical disk 10 is recordable, and at the beginning of each frame as a recording unit, control information including a synchronization signal and a clock signal component in the reproduction-only information is recorded on the entire disk. Is formed by the displacement in the track width direction. Further, on a part of the magneto-optical disk 10, software programs such as an operating system and original data such as dictionary data, audio data, video data, and the like are stored with the control information of each frame due to the displacement in the track width direction. Is recorded and formed in advance. As described above, the magneto-optical disk 10 has the recording-only area 12 and the area 13 in which read-only data is written in advance by displacement in the track width direction and information (main information) can be recorded also in the track direction. Note that the entire area of the magneto-optical disk 10
It is also possible to write reproduction-only data as shown in FIG. For example, the main information to be recorded magneto-optically along the track direction of the recording track 11 may include control information such as a frame synchronization signal, but such control information is recorded in the track width direction displacement. In consideration of the fact that it can be obtained from the reproduction-only information, it may be omitted (not recorded).

FIG. 2 shows a specific example of a recording format of the read-only information recorded by the displacement in the track width direction.

In FIG. 2, a specific example of the information recording format based on the displacement in the track width direction is the same as the format of a so-called CD (compact disk). That is, in the general CD format, one block (one sector) serving as an information recording unit is composed of 98 frames from the 0th frame to the 97th frame, and one frame is 588 times (588T) of the channel clock period T, 1
Each frame has a recording area for a frame synchronization signal, a subcode, and data (including parity). That is, a 24T (24 channel bits) frame synchronization signal and a 14T subcode area are provided at the beginning of one frame, and these are connected via 3T connection bits. The remaining 544T has 32 symbols (32 symbols). 32 bytes) sample data and parity data are so-called EF
It is arranged after being modulated by the M (8-14 modulation) method. The frame synchronization signal has a so-called out-of-rule pattern, which does not exist in the above-mentioned EFM method, because the 11T inversion interval continues twice. The 14T subcode area corresponds to the one symbol.

Here, as the recording information based on the above-mentioned displacement in the width direction in the specific example of FIG. 2, as in the case of the frame synchronization signal in the CD format, a synchronization signal of 24T including a pattern in which the inversion interval of 11T is continuous twice is arranged. 1 through the connection bit of
44T at the beginning of the frame including the 4T subcode and the 3T connection bits is configured. The synchronization signal at the beginning of the frame is used to synchronize in frame units. To synchronize in the block (sector) unit composed of a plurality (98) of these frames, A predetermined portion of the top 44T, for example, 8T of the end portion,
It may be used as a sector mark (block mark) for block synchronization. In other words, by writing a track width direction displacement pattern rising at the center of 8T as the sector mark of the block top frame, and writing a pattern falling at the center of 8T on sector marks of other frames, The block head frame can be distinguished from other frames. Alternatively, similarly to the CD format, patterns S ₀ and S ₁ out of the rule of the EFM modulation (out-of-rule) may be written in each subcode area of the head of the block and the second frame. At this time, for the 8-bit data before modulation (14 channel bits after modulation) in the sub-code area, 98 frames are defined as one block, and 8 channels P to 96 bits each excluding the two frames at the head of the block. W may be configured to express minute, second, and frame address information using the Q channel.

Such control information is recorded as displacement in the track width direction over the entire area of the magneto-optical disk 10 (discretely at the head position of each frame). Is recorded in the data area of 544T other than the above-mentioned 44T at the head of the frame in the 588T (588 channel bits) of one frame by the displacement in the track width direction, so that the partial area 13 of the magneto-optical disk 10 is recorded. Is formed. The modulation method and recording density of the read-only data recorded by this track width direction displacement are, for example, those described above.
The modulation method is the same as the modulation method (EFM) of the CD format, and the recording density is the same as the main information on the recording track. The modulation method is not limited to the EFM method, but may be a PE method, a biphase mark modulation method, or the like, and the recording density can be set arbitrarily. further,
Such read-only original data is transferred to a magneto-optical disk.
It goes without saying that the displacement of the recording track 11 in the track width direction may be recorded on the entire recording track 11.

When recording / reproducing the main information on a recording track along the track direction using a recording medium in which such reproduction-only information is recorded (pre-formatted) in advance by displacement in the track width direction, the reproduction-only information is used. Control information such as the frame synchronization signal obtained from the information can be used. When the main information is recorded, it is not necessary to newly record the control information. Therefore, the control information is omitted, that is, as shown in the magneto-optical recording pattern in each recording track 11 in FIG. Instead of recording a synchronization signal or the like at the beginning of each frame, magneto-optical recording can be performed using only original data as main information along the track direction on the recording track 11. As a result, the ratio of the original data in the main information can be increased, and the recording capacity of the original data can be increased.

Furthermore, since the read-only information is recorded and formed (so-called preformat) in advance by displacement in the track width direction instead of the conventional pit recording, tracking control over the entire area of the disc can be uniformly performed, and switching of the tracking control is performed. In addition to eliminating the need for such information, it is possible to prevent the adverse effects on tracking when recording read-only information using pits, and to improve the responsiveness and stability of the tracking control operation when a track jumps across each area 12, 13. Good.

As described above, a medium such as an optical disk in which read-only information is preformatted by the displacement of the recording track itself in the width direction can be easily mass-produced through a pressing process using a master disk or a stamper at the time of manufacturing the disk.

Next, a recording method of the read-only information recorded and formed by the displacement in the track width direction as described above, for example, a modulation method,
Information is recorded / reproduced using a magneto-optical disk which is a recording medium having the same error correction method, data format and address format, and the same recording method of main information recorded on a recording track along the track direction. A specific example of a recording / reproducing apparatus for performing the above will be described with reference to FIG.

In FIG. 3, the magneto-optical disk 10 has two types of areas 12 and 13 as described above, and spiral or concentric recording tracks are formed as a whole, and read-only information is stored in a ROM area. Recording is performed by displacement in the track width direction. The magneto-optical disk 10 is rotated by a spindle motor 21 at a constant linear velocity (CLV) or a constant angular velocity (CAV). A laser beam from a laser light source 22 (laser diode or the like) for recording / reproducing is converted into a parallel light beam by a collimator lens 23, and then a beam splitter 24, an objective lens of a so-called two-axis device for focusing and tracking.
The light is radiated onto the magneto-optical disk 10 via 25. The reflected beam from the magneto-optical disk 10 is used as a beam splitter
And a polarizing beam splitter 27 through an optical system 26 such as a half-wave plate, a converging lens, and a cylindrical lens.
Is incident on. The polarization beam splitter 27 separates the light into a so-called P-polarized component and an S-polarized component, and outputs a tracking error signal, a focus error signal, and a magneto-optical signal (MO signal).
Signal) are incident on photodetectors 28 and 29 for detecting the signal.

Outputs from the photodetectors 28 and 29 are sent to a differential amplifier 30 to obtain a difference, thereby extracting a magneto-optically recorded information signal (MO signal). The output signal from the differential amplifier 30 is sent to the selected terminal a of the changeover switch 31. In the photodetector 28, for example, a tracking error signal,
The focus error signal is also detected, and a signal of the read-only information recorded by the displacement in the track width direction can be obtained from the high frequency component of the tracking error signal. The track width direction displacement recording signal is sent to the PLL / timing generation circuit 32, where clock reproduction and generation of various timing signals are performed. The track width direction displacement recording signal is sent to the selected terminal b of the changeover switch 31. The output signal from the changeover switch 31 is subjected to, for example, EFM demodulation in a demodulation circuit 33 and sent to an address decoder 34 and an error correction code decoding circuit 35. The data corrected by the decoding circuit 35 is taken out from the data output terminal 37 via the data input / output circuit 40.

As described above, depending on whether the information to be reproduced is read-only information recorded in advance by displacement in the track width direction or main information recorded on the recording track along the track direction, for example, PLL / timing generation is performed. The changeover switch 31 is controlled to be switched by the changeover control signal from the circuit 32, so that one system of the demodulation circuit 33, the address decoder 34,
And an error correction decoding circuit 35 are used for both information. Therefore, it is not necessary to provide a reproducing circuit system for each piece of information, and the reproducing circuit configuration can be reduced by half. Incidentally, the discrimination of each information when the read-only information recorded in advance by the track width direction displacement and the main information recorded along the track direction on the recording track have the same format, Adds identifier information, so-called directories or TOC (table of contents)
May be distinguished by

Here, a recording method (modulation method, error correction method, data format, address format, etc.) of the read-only information recorded in advance by the track width direction displacement.
By making the recording method of the main information recorded on the recording track along the track direction the same as the existing recording method of a so-called CD or the like, various ICs used in the existing CD reproducing device ( (Integrated Circuit), LSI (Large Scale Integrated Circuit) and the like can be used almost as they are, and the design of the disk reproducing circuit system can be simplified, and inexpensive supply is also possible. The same effect can be obtained not only when the recording method is the same as the recording method for an audio CD but also when the recording method is the same as a recording method for a so-called CD-ROM or CDI.

Next, at the time of information recording, the data of the main information to be recorded supplied from the data input terminal 41 is sent to the error correction code encoding circuit 42 through the data input / output circuit 40 and subjected to error correction encoding processing. Then, the signal is subjected to, for example, EFM modulation by the modulation circuit 43, converted into a magnetic field modulation drive signal by the magnetic field modulation drive circuit 44, and sent to the magnetic head 45 for magneto-optical recording. Here, the error correction coding process in the coding circuit 42 and the modulation circuit
In the EFM modulation processing in 43, each processing operation is controlled by a PLL clock signal locked in accordance with at least a frame synchronization signal in the read-only information recorded in the track width direction displacement.

At this time, since the synchronization signal and the clock signal can be obtained from the read-only information recorded by the displacement in the track width direction, it is not necessary to include it in the main information to be magneto-optically recorded. Also, address information can be obtained from the reproduction-only information. Therefore, by not using the synchronization signal and the like as the main information but using the synchronization signal and the like of the reproduction-only information, the ratio of the original data in the main information can be increased, and the original data The recording capacity can be increased.

The present invention is not limited to only the above embodiments. For example, the recording medium may be a magneto-optical disk, a phase-change optical disk, an organic dye-based optical disk, various write-once disks,
It can be applied to overwritable disks and the like, and can be applied to cards and the like in addition to disks. Further, software program data or the like may be recorded by the displacement in the track width direction. Further, the recording format of the track width direction displacement recording information is not limited to the specific example shown in FIG.

H. Effects of the Invention As is clear from the above description, according to the information recording method of the present invention, the recording method of the read-only information pre-recorded and formed by the displacement in the track width direction and the recording method of the main information Are the same, the circuit configuration can be shared. Further, according to the information reproducing method of the present invention, since the main information is reproduced by the same reproducing method as that of the reproduction-only information, not only can the configuration of the reproducing circuit be shared, but also the reproducing circuit itself can be used. Can be shared. Further, according to the recording medium of the present invention, since the read-only information is recorded in the track width direction by the same recording method as the recording method of the main information, it is possible to share the structure of the reproducing circuit.

Furthermore, according to the embodiment of the present invention, by making the recording method of the main information and the recording method of the read-only information the same as the existing recording method of, for example, a CD, it becomes possible to divert an existing IC or LSI. In addition, it is possible to simplify the circuit design and reduce the price of the recording / reproducing apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a magneto-optical disk as an embodiment of a recording medium according to the present invention, FIG. 2 is a diagram showing a specific example of a recording format of read-only information on the disk, and FIG.
FIG. 1 is a block circuit diagram showing a specific example of a recording / reproducing apparatus for explaining an embodiment of an information recording method and an information reproducing method of the present invention. FIG. 4 shows an example of a conventional disk having a read-only area. It is a schematic plan view. 10 ... Magneto-optical disk 11 ... Recording track 21 ... Spindle motor 28, 29 ... Photodetector 31 ... Changeover switch 32 ... PLL / timing generation circuit 33 ... Demodulation circuit 34 ... Address decoder 35 ... Error correction Decoding circuit 42: Error correction coding circuit 43: Modulation circuit

Claims (3)

(57) [Claims] 1. An information recording method for recording main information along a track direction on a recording track formed on a recording medium in advance, wherein the reproduction-only information is recorded on the recording track in advance by displacement in a track width direction. An information recording method, wherein the main information is recorded using a medium in the same recording method as the recording method of the read-only information. 2. An information reproducing method for reproducing main information recorded along a track direction on a recording track formed on a recording medium in advance, wherein reproduction-only information is recorded on the recording track in advance by displacement in a track width direction. An information reproducing method, wherein the main information is reproduced by using the same recording system as that of the reproduction-only information using the recorded recording medium. 3. A recording medium in which main information is recorded along a track direction on a recording track formed in advance, wherein the read-only information has a track width in the recording track by the same recording method as the recording method of the main information. A recording medium formed by recording in advance by directional displacement.