JPH1125607A - Recording medium and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively record discrimination information required in the case of making a recording medium into high density and large capacity without changing an existing data format. SOLUTION: The discrimination information related to recording density is recorded by the combination between the data of a control area (Control) and an address area (ADR) in terms of a sub-code data structure. The control area is composed of four bits, and the address area is composed of four bits also. By setting the most significant bit of the control area as 1, and setting the data value of the address area as 7 (bit value: 0111) or 8 (bit value: 1000), the matter being double density recording is shown.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium and a reproducing apparatus therefor, and more particularly to a recording medium having recording medium identification information such as recording density, recording capacity, and recording layer state.

[0002]

2. Description of the Related Art CD audio, CD-ROM, DVD
And various other recording media have been developed. The recording format of each of these recording media is determined in advance by each standard. For example, in the case of a CD, the external dimensions of the disk, the track pitch, the configuration of data, and the like are finely determined by the CD format. Therefore, there is a certain limit in the recording capacity of a disc as long as such a standard is followed. For example, for CD audio, up to 7
Can only record up to 4 minutes.

[0003] However, recently, densification of each disk has been studied. For example, the recording density can be increased by reducing the track pitch or the pit. Technological developments such as shortening the wavelength of lasers have made it possible to construct recording media with a much higher density than at the time of each standard. Further, if the recording layer is formed of a plurality of layers instead of a single layer, the recording capacity can be further drastically increased.

[0004]

However, in realizing such high density and high capacity, the format of each standard is an obstacle. Of these, the change of the physical format such as the track pitch can be solved by improving the reading accuracy on the reproducing apparatus side, such as shortening the wavelength of the laser, as described above. For compatibility with, fundamental changes to the format must be avoided. Therefore, it is necessary to record the disc identification information required for reproduction within the range of the existing data format.

[0005] However, in the existing data format, in the case of a CD, there is almost no free area in which such identification information can be recorded as it is. If the identification information is simple information, and if it is necessary to simultaneously record several types of information such as recording density, recording capacity, number of recording layers, recording layer number, number of recording layers, etc., an empty area The method of recording in the first place cannot cope very much.

Therefore, the present invention proposes a recording medium which can cope with the above-mentioned high density and high capacity.
The present invention proposes an improvement in a data structure for recording identification information of a medium. Another object of the present invention is to provide a reproducing apparatus suitable for reproducing the recording medium.

[0007]

Means for Solving the Problems In order to solve the above problems,
The recording medium of the present invention is a recording medium on which data is recorded in a standard data format, and by combining a plurality of types of data on the data format,
It is characterized by recording identification information. Here, the “standard data format” refers to a standardized data format such as a CD standard or a DVD standard.

The identification information is, for example, information indicating a recording density, a recording capacity, a recording layer number, and the number of recording layers. Of course, other identification information can be adopted. More specifically, on a recording medium on which data is recorded in a CD format, identification information is recorded by a combination of a plurality of types of data in a frame structure of a sub Q channel.

Here, the identification information can be constituted by, for example, a combination of data in a control area and an address area. The combination of the data in the control area and the address area can indicate, for example, whether or not high-density recording is performed. Further, the number of the recording layer can be indicated by the data value of the address area.

In the CD-format recording medium, the identification information may be constituted by a combination of a POINT area and a PSEC area of a lead-in area. For example, the number of recording layers can be indicated by the combination of the POINT area and the PSEC area.

Further, the recording direction of the recording layer can be indicated by the data value of the PSEC area. In addition, a reproducing apparatus according to the present invention includes an extracting unit that extracts a plurality of types of data from reproduced data, a comparing unit that compares each of the extracted data with a reference value, and identification information of a medium according to the comparison result. And a detecting unit for detecting

Here, the reproducing apparatus switches the setting values of the respective circuits in accordance with the detected identification information, thereby realizing good reproduction by setting the optimum setting values for each disk.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention
This will be described by taking a D-ROM disk as an example. FIG. 1 is a circuit block diagram of a recording system. 1 is the data source,
Information to be recorded in the data area on the CD format
Send to CD encoder 3. 2 is a subcode source,
The information to be recorded in the subcode data area on the CD format is sent to the subcode generator 4. The data sent from the subcode source 2 includes table of contents information (TOC: TaC).
ble of Contents), start time and end time of each track, start time from index 00, Mode2,3
There is information about

The subcode generator 4 receives these data, generates subcode data, and sends it to the CD encoder 3. Then, the CD encoder 3 encodes the subcode data and the data from the data source 1 to create recording data according to the CD format. The transmission timing of the data from the data source 1 and the subcode generator 4 is controlled by a synchronization signal from the CD encoder 3.

The optical modulator 5 receiving the recording data in this manner modulates the intensity of the recording laser and generates a write pulse corresponding to the recording data. Then, the recording light is written by guiding the pulsed light to the master disk set in the writing device. FIG.
Shows the frame structure of the sub Q channel. still,
Since the properties and functions of the data in each area are already known, the description is omitted here.

In the present embodiment, disc identification information is recorded using the data structure of the subcode Q channel. Therefore, in the block diagram of FIG. 1, the data of the subcode source 2 is modified. (1) Identification of High Density Higher density can be achieved by compressing the track pitch and pit length of the disk. In the present embodiment, the track pitch and the pit length are each reduced by a factor of 1 / そ れ ぞ れ 2 so as to obtain a double recording density and a double recording capacity.
The data format remains the existing CD format.

The identification information of such high density is recorded by a combination of data of a control area (Control) and an address area (ADR) on the subcode data structure of FIG. The control area is composed of 4 bits, and the address area is also composed of 4 bits. Among them, the most significant bit of the control area is set to 1 and the data value of the address area is set to 7 (bit value: 0111) or 8
(Bit value: 1000) indicates that the recording is double density recording.

Here, setting the upper 1 bit of the control area to 1 originally indicates that the recording is 4-channel recording. On the other hand, setting the data value of the address area to 7 or 8 is not limited to the case where the data value is used as the identification information for high density as in the present invention, and may have other meanings as appropriate. Therefore, it is not possible to accurately determine whether only the control area or the address area indicates high density. Therefore, by setting these two types of data to the above values, the disc is regarded as a high-density disc, and the certainty of the identification result is improved.

The data states of the control area and the address area are recorded over the lead-in, program, and lead-out areas. This allows
At any position on the disk, it can be determined that high-density recording is performed. (2) Identification of Recording Layer Number In addition to the above-described high density, if a plurality of recording layers are used, the recording capacity can be dramatically improved. Further, by adjusting the focal position of the reading beam, it is possible to read the data of each layer. In this way, if a multi-layer recording is used,
It is necessary to record the layer number as identification information in each layer for the convenience of information retrieval and the like.

In the present embodiment, the data value in the address area is given more significance so that the layer number of each layer can be identified. That is, if the data value of the address area is 7 (bit value: 0111), the first layer, 8 (bit value: 100)
0) indicates the second layer. In this way, the address area is used to indicate the high-density identification information, and further,
By sharing to indicate the identification number of the layer number, 2
Type identification information can be recorded more efficiently.

(3) Identification of Recording Capacity As described above, if the recording density is doubled, the recording capacity is doubled when the recording layer is a single layer. Further, if the number of recording layers is two, three,..., The recording capacity becomes four times, six times,. When various recording capacities exist, it is often convenient for the user to know the recording capacity of the medium in advance.

In the present embodiment, such a recording capacity is expressed by a combination of a TNO area (TNO), a POINT area (POINT) and a PSEC area (PSEC) on the subcode data structure of the lead-in area. In FIG.
The details of the subcode data structure of the lead-in area are shown. The TNO area is composed of 8 bits, and in the lead-in area, the data value is “00” (BCD of 2 digits).
Expression). The POINT area is also composed of 8 bits, and the data value is “A0” or “A1” in a normal CD.
"A2" (2-digit BCD expression). In the present embodiment, the data value of the POINT area is set to “D
0 ”, and the subsequent MIN area (MIN) in FIG.
Has redefined the meaning of the PFRAME area (PFRAM). That is, the POINT area is “D0” and the PSE
If the area C is “00”, the recording layer is a single layer, and if the area is “01” or “02”, it indicates that the recording layer is two layers. Therefore, the apparatus side can identify the recording capacity of the disk based on the information of the higher density (double density) and the information of the number of the recording layers.

The information on the number of recording layers is not limited to a read-only disc, but is also applicable to a recordable disc.
ontents). Thus, the user can know in advance the recording capacity of the disc by selecting a desired recording density at the time of recording. Of course, the recording device may automatically calculate the recording capacity based on the information on the number of recording layers and the information on the recording density set by the user, and display this to the user from the display unit. it can.

(4) Identification of Recording Direction of Recording Layer When there are a plurality of recording layers, the recording direction can be reversed between adjacent recording layers. For example, taking the above-described two-layer recording disk as an example, the first layer can be recorded from the inner periphery to the outer periphery, and the second layer can be recorded from the outer periphery to the inner periphery. By adopting such a recording method, after the reproduction of the first layer is completed, it is possible to smoothly read data continuously without sending the pickup to the inner peripheral portion at a high speed.

However, in this case, it is necessary to indicate the recording direction of each layer as identification information. In the present embodiment, the identification information of the recording direction is shared with the data value of the PSEC area. That is, as described above, when the POINT area is “D0” and the PSEC area is “01”, “the first layer is from the inner circumference to the outer circumference and the second layer is from the outer circumference to the inner circumference”. Record, and similarly, PSEC
When the area is “02”, it indicates that the recording is “the first layer is from the inner circumference to the outer circumference, and the second layer is the recording from the inner circumference to the outer circumference”.

As described above, the TNO area (TNO) and POIN in the subcode data structure of the lead-in area
Various identification information can be recorded by a combination of the T area (POINT) and the PSEC area (PSEC). As shown in FIG. 3, the area that can be redefined by setting the POINT area to “D0” is not limited to the PSEC area. Since there is still more, it is also possible to further record identification information other than the above in each of these areas.

Next, the disc reproducing apparatus will be described with reference to FIG. 1 is a disk, 2 is a spindle motor for driving a turntable holding the disk, 3
Is a motor servo circuit, 4 is a pickup, 5 is a reproduction circuit for shaping a read signal from the pickup into a pulse signal, and 6 is a demodulation unit for demodulating a pulsed code signal. The data from the demodulation unit 6 is sent to a reproduction processing system (not shown).

Reference numeral 7 denotes a focus servo circuit which drives and adjusts the objective lens so that the focal position of the beam is adjusted on the recording layer. Here, in the case of two-layer recording, the initial position of the objective lens is adjusted, and the beam is appropriately focused on each layer. 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. 9 is a code separation unit.
From the subcode data separated and extracted by the subcode separation unit 8, a TNO area (TNO), a POINT area (POINT) and a PSEC area (PSEC) are extracted and written into the memory 10.

Reference numeral 11 denotes a CPU which controls each unit. When the disc 1 is set in the playback device, the TOC of the disc 1
Information is first read. The subcode data is separated from the TOC information by the subcode separation unit 8 via the reproduction circuit 5 and the demodulation unit 6. Then, among the subcode data, the data of the control area (Control) and the address area (ADR), and the TNO area (TNO), P
The CPU 11 monitors data in the OINT area (POINT) and the PSEC area (PSEC), and detects a recording density, a recording capacity, the number of recording layers, a recording layer number, and a recording direction. Among them, TNO area (TNO), POINT area (POINT), P
The SEC area (PSEC) is stored in the memory 10 via the code separation unit 9. Then, the set values of the components such as the reproducing circuit 5 and the focus servo circuit 7 are switched according to the detection results.

For example, in the case of double-density, dual-layer, reverse-direction recording, the reproducing circuit 5 switches the characteristics of the waveform shaping circuit so as to improve the frequency characteristics as compared with a normal dense disk. This is because the pit length is smaller in double density recording than in normal dense recording. Also, the focus servo circuit 7
Switches the initial voltage applied to the objective lens driving unit so that the second layer can be focused on at the timing when the second layer is inverted and reproduced from the reproduction end (lead-out area) of the disc 1.

In this way, the compatible reproduction of the normal dense disk and the double dense disk can be performed. Incidentally, in such a reproducing apparatus, the resolution is enhanced such that the spot diameter of the reading beam is made smaller than in the case of reproducing a normal dense disk so that a double-density disk can be reproduced. For example, the wavelength of the laser beam is shortened, and the numerical aperture (N
A) is adopted.

Although the embodiments of the present invention have been described above, the present invention is not limited to such embodiments. For example, in the above embodiment, a CD-ROM disc has been described as an example, but the present invention can be similarly applied to a CD audio disc. Further, the present invention can be applied not only to a CD disk but also to media of various formats.
Further, the data area used for recording is not limited to the above, and the identification information to be recorded can be variously changed.

In the above embodiment, a read-only disc is used, but the present invention can be applied to a recordable disc. In this case, it is preferable that the identification information derived from the structure of the medium, such as the number of recording layers, be recorded on the medium in advance. However, identification information that is appropriately switched and set at the time of recording, for example, information such as recording density May be written together with the main recording on the recording device side.

[0034]

According to the present invention, various identification information can be efficiently recorded without changing the existing data format. Therefore, in particular, the identification information required for increasing the density and capacity of the disk can be efficiently recorded in the existing data format, and thereby,
Also when performing compatible reproduction with a medium having a normal density, the configuration of the data processing system does not need to be changed so much. That is, on the reproduction circuit side, an extraction unit for extracting a plurality of types of target data from the reproduction data, a comparison unit for comparing each of the extracted data with a reference value, and identification information of the medium according to the comparison result. Various identification information can be detected simply by attaching a detecting section to an existing signal processing system.

[Brief description of the drawings]

FIG. 1 is a block diagram of a recording apparatus.

FIG. 2 is a diagram showing a frame structure of a sub Q channel.

FIG. 3 is a diagram showing a frame structure of a sub Q channel in a lead-in area.

FIG. 4 is a block diagram of a playback device.

[Explanation of symbols]

 Reference Signs List 1 disc 5 reproduction circuit 6 demodulation section 7 focus servo circuit 8 subcode separation section 9 code separation section 10 memory 11 CPU

Claims (14)

[Claims] 1. A recording medium on which data is recorded in a standard data format, wherein identification information is recorded by a combination of a plurality of types of data on the data format. 2. The recording medium according to claim 1, wherein the identification information is information indicating a recording density. 3. The recording medium according to claim 1, wherein the identification information is information indicating a recording capacity. 4. The recording medium according to claim 1, wherein the identification information is information indicating a number of a recording layer of the recording medium. 5. The recording medium according to claim 1, wherein the identification information is information indicating the number of recording layers of the recording medium. 6. A recording medium on which data is recorded in a CD format, wherein a combination of a plurality of types of data in a frame structure of a sub Q channel is used.
A recording medium on which identification information is recorded. 7. The recording medium according to claim 6, wherein the identification information comprises a combination of data in a control area and an address area. 8. The recording medium according to claim 7, wherein a high-density recording is indicated by a combination of data in the control area and the address area. 9. The recording medium according to claim 8, wherein the data value of the address area further indicates a number of a recording layer. 10. The identification information includes a PO in the lead-in area.
The recording medium according to claim 6, which is configured by a combination of an INT area and a PSEC area. 11. The number of recording layers is indicated by a combination of a POINT area and a PSEC area.
A recording medium according to claim 1. 12. The recording medium according to claim 11, wherein the data value in the PSEC area further indicates a recording direction of the recording layer. 13. A reproducing apparatus for reproducing any one of claims 1 to 12, wherein the extracting unit extracts a plurality of types of data from the reproduced data, and compares the extracted data with a reference value. A reproducing apparatus comprising: a detecting unit that detects identification information of a medium according to a comparison result. 14. The reproducing apparatus according to claim 13, wherein a set value of each circuit is switched according to the identification information.