JPH10293971A - Optical disk, device and method for reproducing disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk and its reproducing device capable of long time recording/reproducing without correcting a signal format on a standard. SOLUTION: For recording areas, there prepared two recording areas of a first session and a second session in an inner peripheral side and an outer peripheral side. A read-in part, a program part (user data) and a read-out part are arranged respectively on respective sessions. A transition area lies between the fist session and the second session. A pit is not provided on such a transition area, and thus, the area becomes a mirror surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk such as a compact disk, a video disk, and the like, and a reproducing apparatus therefor, and more particularly to an apparatus capable of recording and reproducing for a long time.

[0002]

2. Description of the Related Art At present, various optical disks such as a compact disk and a video disk have been developed. Also, among compact discs, CD-DA, CD-RO
There are various standards, such as M and CD-I. In each of these standards, the outer shape of the disk, the dimension of the track pitch, and the like are determined in terms of compatibility and the like. In addition, the standard also defines a signal format such as a synchronization signal, data, and error correction.

For example, a CD-ROM has a track pitch of 1.6 μm and a shortest pit length of 0.83 μm.
The signal format is as shown in FIG. 4. One frame, which is the minimum unit, includes a frame synchronization signal, a subcode signal, a data signal, and a parity. The subcode signal is composed of 8 bits of the P to W channels.
One control data is constituted by a data block (96 bits) obtained by collecting channel data (1 bit) for 96 frames.

[0004] In such a subcode signal, the data section contains information on the reproduction time. According to the standard, the allowable range of the reproduction time, that is, the longest continuous reproduction time is 74 minutes. Such a permissible reproduction time is naturally determined based on the outer dimensions of the disk and the recording form such as the track pitch. The track pitch dimensions and the like generally reflect the technical capabilities at the time of setting the standard.

[0005] However, recently, various possibilities have been studied for the production of discs out of the standard range and the reproduction thereof. For example, it is possible to record information at a track pitch smaller than the standard size and to record information of about twice the capacity on a disk having the same outer shape. In this case, if only the mechanism system of the playback device is modified, a playback data stream similar to a standard disc can be realized. Therefore, the existing internal circuit including the signal processing system can be used almost as it is.

[0006]

As described above, in consideration of the signal processing of the recording / reproducing system, it is better not to modify the standard signal format even when the recording density is improved. However, if the playback time is predetermined according to the standard, if the recording is performed for a long time in a single recording area, the upper limit of the playback time under the standard will be exceeded, and the standard Will not be satisfied. If the signal format standard is not satisfied in this way, for example, during reproduction of the disc, it is necessary to change the factor relating to the reproduction time, and at the time of reproduction, special signal processing relating to the reproduction time is required. Therefore, the existing internal circuit cannot cope.

Therefore, the present invention enables long-time recording without modifying the standard signal format.
It is another object of the present invention to provide a novel optical disk capable of performing a reproducing and accessing operation satisfactorily. Another object of the present invention is to provide a reproducing apparatus and a reproducing method for reproducing and accessing the disc satisfactorily.

[0008]

In view of the above-mentioned problems, an optical disk according to the present invention is an optical disk in which a plurality of recording areas having the same recording format and the same signal format are arranged in a radial direction. It is characterized in that data for separating recording areas from each other is superimposed and recorded for each unit recording frame having the signal format.

Here, if each recording area has a lead-in section, a program section, and a lead-out section individually, each recording area can be separated on a signal format and completed for each recording area. The signal area can be configured.
In addition, if a transition area is provided between adjacent recording areas, each recording area can be physically separated. As described above, if each recording area is separated and completed, signals to be recorded on a plurality of discs can be recorded on a single disc almost as it is, so that signal processing for disc production becomes easy. As an example, when compressing information for two disks, two recording areas are prepared on the inner peripheral side and the outer peripheral side.

[0010] When a CD is compressed into a single disc, the signal format is set to the CD format, and the track pitch and / or pit length are compressed to be smaller than the CD format.
For example, information of two CDs can be completely recorded. In such a disc, since the signal format is the same in each recording area, an access operation across recording areas,
It is necessary to specify a target recording area at the time of a mistake in an access operation or a return operation at the time of focus down. For this reason, in the disc of the present invention, data for partitioning the respective recording areas from each other is recorded in a superimposed manner for each unit recording frame, and the reproducing apparatus stores the divided data one by one at the time of reproduction, It is prepared for a return operation at the time of focus down. Also, in the case of an access operation across recording areas,
The recording area being accessed is determined based on the section data read at the time of access.

Therefore, the disk reproducing apparatus of the present invention is characterized in that it has an extracting section for extracting the section data recorded for each frame unit, and a storage section for storing the extracted section data. And An extraction unit for extracting the division data; a storage unit for storing the extracted division data; a target setting unit for setting a target reproduction position; and a set reproduction position and current position. And an access unit that moves the pickup to the target position within the recording area at the target position.

Further, in the disk reproducing method of the present invention, the step of extracting the divided data at the time of reproducing, the step of storing the extracted divided data, and the step of searching a recording area with the extracted divided data as a target. And characterized in that:

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example in which the present invention is applied to a CD-ROM disk will be described below. FIG. 1 is a diagram showing the appearance of a disk. As recording areas, two recording areas of a first session and a second session are prepared on the inner peripheral side and the outer peripheral side. Each session is provided with a lead-in section, a program section (user data), and a lead-out section. A transition area exists between the first session and the second session. No pits are provided in such a transition area, and thus the transition area has a mirror surface.

In each session, pits are formed in a spiral like a conventional CD-ROM, and tracks are formed by the pits. However, the track pitch is 1.1μ
m, the minimum length of the pit is 0.62 μm, which is smaller in the radial direction and the track length direction than the standard values of 1.6 μm and 0.83 μm, respectively. The inner diameter of the first session until the start of the lead-in is 23 mm, and the diameter of the second session until the end of the lead-out is 58.5 mm. The signal format is also as shown in FIG. Such a disc can record about 140 minutes of information, and has a recording capacity about twice that of a standard-compliant disc.

In such a disc, data for discriminating to which session the session at the playback position belongs is necessary due to the necessity of data search and the like. In the present embodiment, the data for such distinction is shown in FIG.
Is recorded as the control code (4 bits) shown in FIG. That is, in the first session, the control code is set to 1100, and in the second session, the control code is set to 1101. The control code itself is included in an existing CD-ROM, but these 1100 and 1101 are not defined.

FIG. 2 is a block diagram of a reproducing apparatus for reproducing such a disk. In the figure, 1 is the above-mentioned disk, 2 is a spindle motor for driving a turntable holding the disk, and 3 is a motor servo circuit.
Reference numeral 4 denotes an optical pickup for scanning tracks on the rotating disk 1, reference numeral 5 denotes a reproducing unit for shaping a read signal from the pickup 4 into a pulse signal, and reference numeral 6 denotes a demodulation unit for demodulating a pulsed code signal. The data from the demodulation unit 6 is output to a reproduction processing system (not shown).

Reference numeral 7 denotes a tracking servo circuit which drives and controls the pickup body and the objective lens.
Position the read beam on the track of the disk.
Reference numeral 8 denotes a sub-code separation unit that separates and extracts sub-code data from the demodulated data by the demodulation unit 6. Reference numeral 9 denotes a control code separation unit that extracts a control code from the subcode data extracted by the subcode separation unit and writes the control code into the memory 10. 11 is a control CPU
Then, control of the above-described units is performed.

Such a reproducing apparatus is designed to be able to reproduce not only the above-mentioned disk but also an existing CD-ROM. That is, the resolution of the pickup 4 is increased, for example, by making the spot diameter of the read beam smaller than that of an existing CD-ROM so as to correspond to the disk of the above embodiment. For example, a method of shortening the wavelength of the laser beam and increasing the numerical aperture (NA) of the objective lens is adopted.

In the double density disc, the pit length is shorter than that of an existing CD-ROM, so that it is necessary to improve the frequency characteristics. Therefore, the reproducing unit 5
Two types of waveform shaping circuits are prepared so as to be compatible with different types of disks, and are configured to be appropriately switched according to the type of disk. Such switching is performed according to an instruction from the CPU 11. By monitoring the control code, the CPU 11 determines whether the disc is a double-density disc.

If a part of the reproduction system is adjusted as compared with the case of the CD-ROM, the configuration of the signal processing system after the demodulation unit 6 can be kept unchanged. FIG.
It is a flowchart which shows the information search method of the said double density disk. The control is performed by the CPU 11. The control program is stored in the CPU 11 or a ROM (not shown). When the access destination session number and address (elapsed time information) are entered through the operation panel,
The control code in the memory 10 is read, and it is determined whether the control code of the access destination matches the current control code (step 100). Here, if they match, the pickup is accessed to the target position in the same session based on the elapsed time information (step 500), and reproduction is started from the designated time (step 600).

On the other hand, if it is determined in step 100 that the control code of the access destination does not match the current control code, the current pickup position is set to the inner peripheral side (the 1
Session) (step 20).
0), if it is on the inner circumference side, on the outer circumference side (step 300)
If it is on the outer peripheral side, it is on the inner peripheral side (step 400).
The pickup is accessed. Then, when the session switching is completed, steps 500 and 600 are executed in the same manner as described above, and the search and reproduction of the target position are performed in the session.

Such information retrieval is executed even when the pickup position fluctuates greatly due to disturbance during reproduction or pause. In such a case, the control code immediately before the occurrence of the disturbance stored in the memory 10 is set as the target session in accordance with the detection of the occurrence of the disturbance. The elapsed time information before the occurrence of the disturbance is usually stored in a memory (not shown), and may be set as a target address similarly to the control code.

The embodiment of the present invention has been described above.
The present invention is not limited to such an embodiment, and various other modifications are possible. For example, in the above embodiment, the CD-RO
M is a specific example, but is not limited thereto.
-I and VD are also applicable. Further, the shape and the like of the disk are configured such that the track pitch and the like are compressed with the same outer dimensions, but the configuration may be such that the track pitch is fixed and the diameter of the disk is increased. Further, the track pitch and the pit length can adopt a compression size other than the above embodiment. Further, not only two recording areas as in the above embodiment, but also three or more recording areas may be prepared.

[0024]

As described above, according to the present invention, it is possible to realize an optical disk capable of recording and reproducing for a long time without modifying the standard signal format, and a reproducing apparatus therefor. Therefore, it is not necessary to change various factors at the time of manufacturing the disc, and the signal processing system necessary for reproduction can be used almost as it is, and recording and reproduction can be achieved extremely efficiently and effectively for a long time.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a disc of the present invention.

FIG. 2 is a diagram showing an example of a reproducing apparatus according to the present invention.

FIG. 3 is a flowchart illustrating an example of information retrieval according to the present invention.

FIG. 4 is a diagram showing a format of a CD-ROM.

[Explanation of symbols]

 8 Subcode separation unit 9 Control code separation unit

Claims (9)

[Claims] 1. An optical disc in which a plurality of recording areas having the same recording format and the same signal format are arranged in a radial direction, wherein data for separating the recording areas from each other is converted from the signal format. An optical disc characterized by being superimposed and recorded for each unit recording frame. 2. The optical disc according to claim 1, wherein each recording area has a lead-in section, a program section, and a lead-out section individually. 3. The optical disc according to claim 1, wherein a continuous or discontinuous transition area is provided between adjacent recording areas. 4. The optical disk according to claim 1, wherein two recording areas are provided on an inner peripheral side and an outer peripheral side. 5. The optical disk according to claim 1, wherein the signal format is a CD format, and the recording format is such that a track pitch and / or a pit length are compressed as compared with the CD format. 6. The total reproduction elapsed time of each recording area is 10
The optical disc according to claim 5, wherein the optical disc lasts longer than 0 minutes. 7. A plurality of recording areas having the same recording format and the same signal format are arranged in the radial direction,
A disk reproducing apparatus for reproducing an optical disk on which data for partitioning each of the recording areas is superimposed and recorded for each unit recording frame having the signal format, wherein: A disc reproducing apparatus comprising: an extracting unit; and a storage unit for storing the extracted section data. 8. A plurality of recording areas having the same recording format and the same signal format are arranged in the radial direction,
A disk reproducing apparatus for reproducing an optical disk on which data for partitioning each of the recording areas is superimposed and recorded for each unit recording frame having the signal format, wherein: An extraction unit, a storage unit for storing the extracted division data, a target setting unit for setting a target reproduction position, and comparing the division data between the set reproduction position and the current position to compare the target position with the target position. A disc reproducing apparatus comprising: an area discriminating unit that moves a pickup to a recording area, and an access unit that causes the pickup to approach a target position within the recording area at the target position. 9. A plurality of recording areas having the same recording format and the same signal format are arranged in the radial direction,
A disk reproducing method for reproducing an optical disk on which data for partitioning each recording area is superimposed and recorded for each unit recording frame having the signal format, wherein the divided data is extracted at the time of reproduction. A disc reproducing method, comprising: a step; storing the extracted section data; and searching a recording area with the extracted section data as a target.