KR100846776B1 - Optical disc having two or more recording layers, recording method and reproducing method therefor - Google Patents

Abstract

Disclosed are an optical disc provided with a plurality of recording layers, a recording method thereof, and a reproduction method thereof.

An optical disc according to the present invention includes at least two recording layers having a lead-in area, a data area, and a lead-out area, wherein at least one of the recording layers is provided with a BCA area in which disc-specific information is recorded. And at least one of the lead-in area and the lead-out area is provided with a reproduction-only area provided with a BCA pointer zone in which pointer information on the BCA area is recorded. Thereby, recording / reproducing of data can be performed more reliably.

Description

Optical disc having two or more recording layers, recording method and reproducing method therefor}

1 is a schematic diagram of an optical disk according to an embodiment of the present invention;

2 is a reference diagram showing a recording / reproducing direction of the optical disc of FIG. 1;

3 is a schematic diagram of an optical disk according to another embodiment of the present invention;

4 is a reference diagram showing a recording / reproducing direction of the optical disc of FIG. 3;

5 is a schematic diagram of an optical disk according to another embodiment of the present invention;

6 is a reference diagram showing a recording / reproducing direction of the optical disk of FIG. 5;

7 is a data structure diagram of a lead-in / out area according to the present invention;

8 is an embodiment of a data structure of a read only area in which BCA pointer information is recorded according to the present invention;

9 shows a first example of formation of a read only area and a rewritable area;

10 shows a second example of formation of a read only area and a rewritable area;

11 is a third example of formation of a read only area and a rewritable area;

12 shows a fourth example of formation of a read only area and a rewritable area;

13 to 17 are reference diagrams for explaining a modulation method of a wobble signal,                 

18 is a flowchart for explaining a recording / reproducing method according to a preferred embodiment of the present invention.

The present invention relates to an optical disc, and more particularly, to an optical disc having at least two recording layers, a recording method thereof, and a reproduction method thereof.

Optical discs, which are widely used information storage media, include CDs and DVDs. However, as the production and distribution of digital contents having a relatively large data size such as AV data become active, an optical disk having a larger recording capacity is required to record them.

One way to increase the recording capacity of an optical disc is to provide two or more recording layers on which user data is recorded. However, in the case of two recording layers, recording and reproducing more reliably are more difficult than in the case of one recording layer. This is because, for example, since the laser beam must be more precisely controlled to read information recorded in each recording layer, errors in information reading may occur more frequently due to contamination of the disk surface.

For example, an optical disc has a BCA zone that records unique information about the disc, ie, serial number, date of manufacture, and the like. In order to read or record information from the optical disc, it is necessary to properly read the disc specific information recorded in the BCA zone and transfer it to a drive for controlling the optical pickup provided in the recording / reproducing apparatus. However, as described above, in the case of two recording layers, it is not easier to properly read disc unique information.

Accordingly, an object of the present invention is to provide an optical disc having a data structure capable of reading disc-specific information more reliably for recording or reproducing data more reliably when it has at least two recording layers, a recording method and a reproduction method thereof. In providing.

The object is, according to the present invention, provided with at least two recording layers having a lead-in area, a data area, and a lead-out area, wherein at least one of the recording layers has a BCA area in which disc-specific information is recorded. And at least one of the lead-in area and the lead-out area is provided with a reproduction-only area provided with a BCA pointer zone in which pointer information for the BCA area is recorded.

Preferably, the BCA pointer zone is formed in a lead-in area or a lead-out area of the recording layer provided with the BCA area, and the pointer information includes information on the existence of the BCA area and recording position information.

In addition, the object may include a first recording layer having a first lead-in area, a first data area, and a first lead-out area; And a second recording layer in which a second lead-in area, a second data area, and a second lead-out area are formed, wherein at least one of the first recording layer and the second recording layer has disk unique information recorded thereon. A BCA area is provided, and at least one of the first lead-in area and the second lead-in area is provided with a reproduction-only area provided with a BCA pointer zone in which pointer information on the BCA area is recorded. It is also achieved by the disk.

The BCA pointer zone is formed in the first recording layer and the second recording layer, respectively, and preferably includes information on the presence or absence of the BCA area and recording position information.

On the other hand, according to another field of the present invention, the above object is, in the method for recording user data or playing recorded user data on an optical disk provided with at least two recording layers

Reading BCA pointer information from a BCA pointer zone formed in either one of an inner circumference and an outer circumference of the disc of a predetermined recording layer; And reading out the BCA pointer information from a BCA pointer zone formed on the other of the outer and inner circumferences of another recording layer if the BCA pointer information is not read correctly. Providing read BCA pointer information to a drive; And recording the user data on the optical disc or reproducing the recorded user data through control of the drive based on the provided BCA pointer information.

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

1 is a schematic diagram of an optical disk according to an embodiment of the present invention.

Referring to Fig. 1, an optical disk is provided with a first recording layer L0 and a second recording layer L1. Between each recording layer there is a space layer (not shown) that physically separates the layers. In this embodiment, the thickness of the substrate (not shown) on the side on which light is incident is 0.6 mm or 0.1 mm.

The first recording layer LO and the second recording layer LI are provided with a clamping area C, a lead-in area LI, and a lead-out area LO. The clamping area C refers to the area pressed by the clamping mechanism for clamping the disk. In general, the clamping region C has a circular band shape at the center of the inner peripheral side of the disk. There exists a data area in which user data is recorded between the lead-in area LI and the lead-out area LO. On the other hand, a BCA (Burst Cutting Area) area B is formed between the clamping area C and the lead-in area LI of the first recording layer LO. In the BCA area B, unique information about the disc is recorded. Disc specific information includes serial numbers, date of manufacture, and the like. When the first recording layer LO is formed of a phase change film, the disc specific information is recorded in a mark pattern in which crystalline and / or amorphous marks are arranged. More detailed information on the method of recording the disc unique information in the BCA area is described in Korean Patent Application No. 2001-47957, "Optical disc, unique information recording method for optical disc, and reproduction method thereof" filed by the present applicant.

FIG. 2 shows the recording / reproducing direction of the optical disc of FIG.

Referring to Fig. 2, the hatched area represents the lead-in area LI and the lead-out area LO, and the remaining area represents a data area in which user data is recorded.

When recording / reproducing of data proceeds from the inner circumference to the outer circumference when the disk is rotated counterclockwise when viewed from the direction of the laser beam irradiation, the recording / reproducing path of the optical disk of FIG. The OTP (Opposite Track Path) method starts from the lead-in area, passes through the lead-out area, passes through the lead-in area of the second recording layer L1, and ends in the lead-out area. That is, in the present specification, the lead-in area means an area located at a point where recording / reproduction starts in the corresponding recording layer, and the lead-out area means an area located at a point where recording / reproduction ends in the corresponding recording layer. Thus, the lead-in area may be formed on the outer circumference or inner circumference of the disk and the lead-out area may also be formed on the outer circumference or inner circumference of the disk. In this embodiment, the lead-in area of the first recording layer L0 is formed on the inner circumference of the disk, the lead-out area is formed on the outer circumference of the disk, and the lead-in area of the second recording layer L1 is on the outer circumference of the disk. And the lead-out area is formed in the inner circumference of the disk.

3 is a schematic diagram of an optical disk according to another embodiment of the present invention.

Referring to Fig. 3, an optical disk is provided with a first recording layer L0 and a second recording layer L1. The first recording layer LO and the second recording layer LI are provided with a clamping area C, a lead-in area LI, and a lead-out area LO. The clamping area C refers to the area pressed by the clamping mechanism for clamping the disk. In general, the clamping region C has a circular band shape at the center of the inner peripheral side of the disk. There exists a data area in which user data is recorded between the lead-in area LI and the lead-out area LO. On the other hand, a BCA region B is formed between the clamping region C and the lead-in region LI of the first recording layer LO. In the BCA area B, unique information about the disc is recorded. Disc specific information includes serial numbers, date of manufacture, and the like. When the first recording layer LO is formed of a phase change film, the disc specific information is recorded in a mark pattern in which crystalline and / or amorphous marks are arranged. More detailed information on the method of recording the disc unique information in the BCA area is described in Korean Patent Application No. 2001-47957, "Optical disc, unique information recording method for optical disc, and reproduction method thereof" filed by the present applicant.

In the optical disk of FIG. 3, the lead-in area and the lead-out area are arranged opposite to each other as compared with that described with reference to FIG. 1. That is, in this embodiment, the lead-in area of the first recording layer L0 is formed on the outer circumference of the disk, the lead-out area is formed on the inner circumference of the disk, and the lead-in area of the second recording layer L1 is It is formed on the inner circumference and the lead-out area is formed on the outer circumference of the disk.

4 shows the recording / reproducing direction of the optical disc of FIG.

Referring to Fig. 4, the hatched area represents the lead-in area LI and the lead-out area LO, and the remaining area represents the data area in which user data is recorded.

When recording / reproducing of data proceeds from the inner circumference to the outer circumference when the disk is rotated counterclockwise when viewed from the direction of the laser beam irradiation, the recording / reproducing path of the optical disk of FIG. The OTP (Opposite Track Path) method starts from the lead-in area, passes through the lead-out area, passes through the lead-in area of the first recording layer L0, and ends in the lead-out area.                     

5 is a schematic diagram of an optical disk according to another embodiment of the present invention.

Referring to Fig. 5, an optical disk is provided with a first recording layer L0 and a second recording layer L1. The first recording layer LO and the second recording layer LI are provided with a clamping area C, a lead-in area LI, and a lead-out area LO. The clamping area C refers to the area pressed by the clamping mechanism for clamping the disk. In general, the clamping region C has a circular band shape at the center of the inner peripheral side of the disk. There exists a data area in which user data is recorded between the lead-in area LI and the lead-out area LO. On the other hand, the BCA area B is formed between the clamping area C and the lead-in area LI of the second recording layer L1. In the BCA area B, unique information about the disc is recorded. Disc specific information includes serial numbers, date of manufacture, and the like. When the second recording layer L1 is formed of a phase change film, the disc specific information is recorded in a mark pattern in which crystalline and / or amorphous marks are arranged. More detailed information on the method of recording the disc unique information in the BCA area is described in Korean Patent Application No. 2001-47957, "Optical disc, unique information recording method for optical disc, and reproduction method thereof" filed by the present applicant.

Compared with that described with reference to FIG. 1, the optical disc of FIG. 5 has a different recording layer in which the BCA area exists. In other words, in this embodiment, the BCA area is formed in the second recording layer L1.

FIG. 6 shows the recording / reproducing direction of the optical disk of FIG.

Referring to Fig. 6, the hatched area represents the lead-in area LI and the lead-out area LO, and the remaining area represents the data area in which user data is recorded. The recording / reproducing path of the optical disc of FIG. 5 starts in the lead-in area of the first recording layer L0 / second recording layer L1 and passes through the lead-out area to lead-in the second recording layer L1 / first recording layer L0. PTP (Parallel Track Path) method that passes through the in area and terminates in the lead-out area.

7 is a data structure diagram of a lead-in / out area according to the present invention.

Referring to Fig. 7, the lead-in / out area is provided with a read-only area and a rewritable area. The reproduction-only area is an area in which reproduction-only data, which is not erased once recorded, is recorded in advance, and the rewritable area is an area in which rewritable data for newly recorded user data is recorded in the data area.

In the reproduction-only area, a BCA pointer zone is provided in accordance with the present invention. In the BCA pointer zone, pointer information for the BCA area is recorded. In the present embodiment, the BCA pointer information is composed of information on whether a BCA region exists, and location information indicating where it is located.

Other data recorded in the reproduction-only area may include disc related information. For example, control codes such as reference code and disc type, disc size, version number, recording density, number of recording layers, and sector number representing a data area can be recorded to make adjustment of the optical pickup such as a focus position easier. have.

In the rewritable area, a test zone, a disc control data zone, and a defect management zone may be provided. The test zone includes a disk test zone and / or a drive test zone. The disc test zone and the drive test zone are areas for testing write pulses and the like. In the disc control data zone, control data relating to user data newly recorded in the data area is recorded. The defect management zone records information for processing or managing a defect which has occurred when a defect occurs in the disc.

Various control data can be recorded in the disc control data zone. In the present embodiment, the disc control data zone is provided with a plurality of areas in which predetermined control data is recorded, and there is an area reserved for future use. An example of control data is drive information. Drive information is information about a drive used in recording, and includes manufacturer information, an identifier, and the like.

However, when the lead-in / out area of the predetermined recording layer has the above-described data structure, the lead-out / in area of the same layer has only the defect management zone and the buffer zone. The meaning of the defect management zone is as described above, and the buffer zone indicates a kind of transition region, that is, a boundary between predetermined regions or regions.

8 shows an embodiment of a data structure of a read-only area according to the present invention.

Referring to Fig. 8, whether or not the BCA area is recorded and its position information is recorded as the BCA pointer information in the reproduction-only area. In addition, the play-only area includes disc type information indicating whether the disc is recordable / erased as a disc-related information, disc recording or reproducing only once, disc size information represented by the diameter of the disc, version number, Disc structure information indicating the number of recording layers, power and time conditions necessary for recording / reproducing, and the like are recorded.

In the present embodiment, pointer information is recorded using the m th byte. That is, the first 4 bits are recorded as the information of 1 byte indicating the recording position information and the remaining 4 bits indicate the presence information. If the first 4 bits indicate the layer in which the BCA region exists, it can be defined as follows.

0000b: first recording layer L0

0001b: Second recording layer l1

0010b: First recording layer L0 and second recording layer L1

Others: Reserved

The remaining four bits are defined as follows.

0000b: BCA area does not exist

0001b: BCA domain exists.

For example, if the BCA area is provided in the first recording layer L0 and not recorded in the second recording layer L1, m bytes are expressed as follows.

 00000001b

If the number of recording layers exceeds two or for other reasons it is difficult to display the BCA pointer information in one byte (when the number of bits is insufficient), another byte can be used.

An example of the formation of the read only area and the rewritable area including the BCA area having the above data structure will be described below.

9 shows a first example of formation of the read only area and the rewritable area.

As shown in Fig. 9, the read only area and the rewritable area are formed as wobble tracks. Here, data of the read only area is recorded in land pre-pits, and data of the rewritable area is recorded on a wobble signal.

Fig. 10 shows a second example of formation of the read only area and the rewritable area.

As shown in Fig. 10, the reproduction-only area is formed of a high frequency wobble track on which high frequency wobble signals are loaded, and a rewritable area is formed of low frequency wobble tracks on which low frequency wobble signals are loaded.

9 and 10, since both the read only area and the rewritable area are formed as wobble tracks like the data area, the physical characteristics are uniform throughout the disc, and the reproduction characteristics are good even when two or more recording layers are provided.

11 shows a third example of formation of the read only area and the rewritable area.

As shown in Fig. 11, the reproduction-only area is formed of a pre-pit area in which corresponding data is recorded pre-pit, and the rewritable area is formed of a wobble track in which a wobble signal containing corresponding data is recorded. Similarly, as the rewritable area is formed as a wobble track like the data area, the rewritable area has a more uniform physical shape, and the reproduction characteristics are good even when two or more recording layers are provided.

12 shows a fourth example of formation of the read only area and the rewritable area.

As shown in Fig. 12, the reproduction-only area is formed of a wobble track in which a wobble signal containing corresponding data is recorded, and the corresponding data in the rewritable area is recorded as a recording mark in the wobble track of the reproduction-only area. This is advantageous in that the data of the read only area in one area is a wobble signal, and the data in the rewritable area is recorded as a recording mark, so that the data area in which the user data is recorded is relatively widened to increase the recording capacity.

On the other hand, the above-described wobble track may be formed on both sidewalls of the grooves and lands as shown in FIG. 13A or only on one sidewall of the lands or grooves as shown in FIG.

Further, the wobble signal read out from the wobble track is modulated in the following manner to carry data. The modulation scheme of FIG. 14A is a frequency modulation scheme. The data is recorded by differentiating the frequency when the data bit takes the logic value "0" and the frequency when the data bit takes the logic value "1". 14 (b) shows a phase modulation method. Data is recorded by differentiating the phase of the wobble signal when the data bit takes the logic value "0" and the phase of the wobble signal when the data bit takes the logic value "1". FIG. 14C shows an amplitude modulation method. Data is recorded by differentiating the amplitude of the wobble signal when the data bit takes the logic value "0" and the amplitude of the wobble signal when the bit takes the logic value "1". FIG. 15 may employ a minimum shift keying (MSK) method for changing only a frequency of a portion of a continuous wobble signal or a sawtooth wobble (STW) method for recording a sawtooth-shaped wobble signal as shown in FIG. . In the sawtooth wobble signal, a logic value "0" or "1" is determined according to the inclination direction of the sawtooth. Further, as shown in FIG. 17, the track pitches TP1 and TP2 of the wobble tracks on which wobble signals are recorded may be configured differently to reduce crosstalk between tracks.                     

The recording / reproducing method according to the present invention will be described based on the above configuration.

18 is a flowchart showing a recording / reproducing method according to a preferred embodiment of the present invention.

Referring to FIG. 18, when an optical disc is loaded into the recording / reproducing apparatus (step 181), the optical pickup provided in the recording / reproducing apparatus is a BCA pointer present in either one of the first recording layer L0 and the second recording layer L1. The BCA pointer information is read from the zone (step 182). If the BCA pointer information is not reproduced correctly (step 183), the optical pickup provided in the recording / reproducing apparatus reads out the disc related information from the disc related information zone present in the other one of the first recording layer L0 and the second recording layer L1. In operation 184, the user data is recorded in the data area or the user data recorded in the data area is reproduced (step 185). That is, the read BCA pointer information is provided to the optical pickup drive provided in the recording / reproducing apparatus, and the drive controls the optical pickup based on the provided BCA pointer information to record user data on the optical disc or reproduce the recorded user data. do.

If the BCA pointer information is correctly reproduced without error (step 183), the user data is recorded in the data area or the user data recorded in the data area is reproduced based on this (step 185).

However, the recording / reproducing method of FIG. 18 assumes that the BCA pointer zones according to the present invention are provided in at least two recording layers, and the two or more BCA pointer zones exist in different areas of each recording layer. For example, the BCA pointer zone of the first recording layer is located on the inner circumference of the disk and the BCA pointer zone of the second recording layer is located on the outer circumference of the disk. That is, even if the surface of the disc is damaged by dust or the like and fails to read the BCA pointer information from the BCA pointer zone provided in the predetermined recording layer, the BCA pointer information can be read from the BCA pointer zone existing in another position of the other recording layer. Because.

As described above, according to the present invention, even in the case of an optical disc provided with two or more recording layers, the BCA pointer information can be read more reliably, thereby improving recording / reproducing characteristics.

Claims (20)

At least two recording layers having a lead-in area, a data area, and a lead-out area, At least one of the recording layers is provided with a BCA area in which disc unique information is recorded. And at least one of the lead-in area and the lead-out area is provided with a reproduction-only area provided with a BCA pointer zone in which pointer information for the BCA area is recorded. The method of claim 1, And at least one of the lead-in area and the lead-out area is provided with a rewritable area for reproducing user data recorded in the data area. The method of claim 1, And the BCA pointer zone is formed in a lead-in area or a lead-out area of a recording layer provided with the BCA area. The method according to any one of claims 1 to 3, And the pointer information includes information on whether the BCA area exists and recording position information. The method of claim 4, wherein The pointer information may be recorded in one byte, Wherein the first 4 bits indicate the recording position information and the remaining 4 bits indicate the presence information. A first recording layer having a first lead-in area, a first data area, and a first lead-out area; And A second recording layer in which a second lead-in area, a second data area, and a second lead-out area are formed; At least one of the first recording layer and the second recording layer has a BCA area in which disc-specific information is recorded. And at least one of the first lead-in area and the second lead-in area is provided with a reproduction-only area provided with a BCA pointer zone in which pointer information for the BCA area is recorded. The method of claim 6, And at least one of the lead-in area and the lead-out area is provided with a rewritable area for reproducing user data recorded in the data area. The method of claim 6, The BCA pointer zone is formed in a recording layer provided with the BCA area. The method of claim 6, And the BCA pointer zone is formed in the first recording layer and the second recording layer, respectively. The method according to any one of claims 6 to 9, And the pointer information includes information on whether the BCA area exists and recording position information. The method of claim 10, The pointer information may be recorded in one byte, Wherein the first 4 bits indicate the recording position information and the remaining 4 bits indicate the presence information. The method of claim 11, The first four bits " 0000 " mean the first recording layer, the first four bits " 0001 " represent the second recording layer, and the first four bits " 0010 " mean both the first recording layer and the second recording layer. Characterized by an optical disk. The method of claim 12, And the remaining four bits " 0000 " mean that the BCA region does not exist, and the remaining four bits " 0001 " means that the BCA region exists. The method of claim 7, wherein The reproduction-only area is formed of a wobble track in which corresponding data is recorded as land pre-pits, And the rewritable area is formed of a wobble track in which a wobble signal containing corresponding data is recorded. The method of claim 7, wherein The reproduction-only area is formed of a high frequency wobble track in which high frequency wobble signals containing corresponding data are recorded. And the rewritable area is formed of a low frequency wobble track on which a low frequency wobble signal containing corresponding data is recorded. The method of claim 7, wherein The reproduction-only area is formed as a pre-pit area in which corresponding data is recorded as a pre-pit, And the rewritable area is formed of a wobble track in which a wobble signal containing corresponding data is recorded. The method of claim 7, wherein The reproduction-only area is formed of a wobble track in which a wobble signal containing corresponding data is recorded, The corresponding data of the rewritable area is recorded in a wobble track of the reproduction-only area as a recording mark. The method according to any one of claims 14 to 17, And the data carried on the wobble signal is modulated by at least one of frequency modulation, amplitude modulation, phase modulation, and sawtooth modulation. A method of recording user data or reproducing recorded user data on an optical disc provided with at least two recording layers, (a) reading BCA pointer information from a BCA pointer zone formed in one of an inner circumference and an outer circumference of the disc of a predetermined recording layer; And (b) reading the BCA pointer information from a BCA pointer zone formed on the other of the outer and inner circumferences of another recording layer if the BCA pointer information is not read correctly; And (c) recording user data on the optical disc or reproducing the recorded user data based on the read BCA pointer information. The method of claim 19, Step (c) is Providing the BCA pointer information to a drive; And Recording the user data on the optical disc or reproducing the recorded user data through the control of the drive based on the provided BCA pointer information.

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