CN1698104A - RECORDING MEDIUM WITH COPY PROTECTION INFORMATION FORMED IN SPACE OR ALTERNATELY DICKED PITS AND APPARATUS AND METHOD FOR FORMING, RECORDING AND REPRODUCING THE RECORDING MEDIUM - Google Patents

Abstract

A recording medium, such as a high-density and/or read-only recording medium (such as BD-ROM), which contains copy protection information encoded in intermittent or alternating wobbled pits, and methods and apparatuses for forming, recording, and reproducing data on the recording medium.

Description

RECORDING MEDIUM WITH COPY PROTECTION INFORMATION FORMED IN SPACE OR ALTERNATELY DICKED PITS AND APPARATUS AND METHOD FOR FORMING, RECORDING AND REPRODUCING THE RECORDING MEDIUM

Technical area

The present invention relates to a recording medium such as a BD-ROM (Blu-ray Disc) having data written in spaced or alternately wobbling (or zigzag) pits, and to an apparatus for forming, recording and reproducing the recording medium and method.

Background technique

Recently, standards for Blu-ray Disc Rewritable (BD-RE) are being formulated as a new type of high-density rewritable optical disc capable of recording large-capacity high-quality video and audio data. It is expected that in the near future, related products of BD-RE will be available on the market.

FIG. 1A describes the structure of a BD-RE. As shown in the figure, it sequentially shows a clamping area, a burst cut area (BCA), a transition area, a lead-in area, a data area, and a lead-out area.

As shown in Figure 1B, the BCA is located in the innermost circumferential area of the BD-RE. When the disc is loaded into a reproduction device, the BCA is first accessed, and it may contain information about the disc, such as the serial number, and the pre-recorded Other optional information.

The lead-in area may include several pre-allocated areas, such as the first guard area (Guard1), the permanent information and control data (PIC) area, the second guard area (Guard2), the second information area (Info2), and the best Power will calibrate (OPC) area. The first protected area and the PIC area are pre-recorded areas with some initial data pre-recorded, while other areas such as lead-in area, data area and lead-out area are all rewritable areas.

In the PIC area, the disc's important permanent information is encoded with wobbled grooves by high frequency modulation (HFM).

The HFM grooves are radially modulated by a signal of relatively high bandwidth, resulting in a data channel of sufficient capacity and data rate for the reproduced information.

Data encoding in the form of dithering is implemented by biphase modulation as described in FIG. 2 . In this modulation method, a binary code with a value of 0 is represented by transitions at the beginning of the bit cell, and a binary code with a value of 1 is represented by transitions at the beginning and middle of the bit cell. The modulated bits are recorded on the disc with a groove offset from the mean centerline shown in FIG. 2 . The length of each bit unit shall be 36T, where T corresponds to the bit length of a channel in the rewritable data area.

Along with BD-RE was developed the Blu-ray Disc Read Only (BD-ROM). As shown in FIG. 3, a BD-ROM disc may include an inner area, a clamp area, a transition area, an information area, and a border area.

The information area may further include a BCA, a lead-in area, a data area, a lead-out area, and an outer area. For BD-RE, the BCA may contain Disc Important Information (DII), such as Disc Serial Number and Copy Protection Information (CPI). If a certain BD-ROM is copy-protected, it is necessary to use DII to decrypt the main information contained in the BD-ROM.

Disc information in the PIC area may be recorded as linear pits, like main data such as audio/video (A/V) streams recorded in the data area. For example, the disc information may be 17PP modulated data written in the form of error correction code (ECC) blocks with a size of 64 kb.

However, since the disc information can be demodulated by the RF signal detection method, some demodulation time is required to retrieve the disc information from the BD-ROM in this case,

As described above, the disc information contained in the PIC area of the BD-RE can be coded in the wobble groove by HFM. If the disc information is recorded in the PIC area of the BD-ROM in the form of linear pits, the disc reproducing device should be able to adopt different detection methods to obtain the disc information based on the disc type (BD-RE or BD-ROM). Unless the correct method is selected, disc reproduction devices will not be able to detect disc information. For example, for a method for detecting information on an optical disc encoded with a BD-RE wobble groove and modulated by HFM, if it is used for a BD-ROM, an optical disc reproduction device will not be able to retrieve Disc information in the PIC area.

Furthermore, if the disc important information (DII) contained in the BCA cannot be retrieved due to some kind of reading error, it will be impossible to retrieve the data recorded on the disc. For example, if some kind of error occurs when copy protection information (CPI) is retrieved from the BCA, it may be impossible to reproduce the main data recorded in the data area because the data cannot be decrypted.

Also, since the copy protection information (CPI) recorded in the PIC area of the optical disc includes important data such as key data for decrypting the encrypted main data recorded in the data area, in order to protect the encrypted content recorded on the optical disc, This copy protection information should not be easily detected by any illegal equipment and copied to other recording media. It can only be detected by predetermined detection methods of legitimate devices to ensure robustness.

Contents of the invention

In an exemplary embodiment, the present invention relates to a recording medium, such as a high-density and/or read-only recording medium such as a BD-ROM, capable of quickly detecting the Optical disc information, the present invention also relates to methods and devices for forming, recording and reproducing data on a recording medium.

In an exemplary embodiment, the invention relates to a recording medium, such as a high-density and/or read-only recording medium (such as a BD-ROM), even when reading disc-critical information from one or more locations on the recording medium By mistake, the recording medium is also capable of reproducing main data, and the present invention also relates to a method and apparatus for forming, recording and reproducing data on a recording medium.

In an exemplary embodiment, the present invention relates to a recording medium, such as a high-density and/or read-only recording medium (such as a BD-ROM), which includes means for decrypting information from being copied to other recording media and/or or other types of recording medium to decrypt the content recorded on the recording medium, and the present invention also relates to methods and devices for forming, recording and reproducing data on the recording medium.

In an exemplary embodiment, the invention relates to a recording medium, such as a high-density and/or read-only recording medium (such as a BD-ROM), contained on certain sectors of the recording medium, such as a PIC area, to The invention also relates to a method and apparatus for forming, recording and reproducing data on a recording medium.

In an exemplary embodiment, the invention relates to a recording medium, such as a high-density and/or read-only recording medium (such as a BD-ROM), contained in one or more locations (such as BCA and other than BCA important information on an optical disc in another area), and the present invention also relates to methods and devices for forming, recording and reproducing data on a recording medium.

In an exemplary embodiment, the invention relates to a recording medium, such as a high-density and/or read-only recording medium (such as a BD-ROM), which contains copy protection information encoded in wobble pits, and to A method and apparatus for forming, recording and reproducing data on a recording medium.

In an exemplary embodiment, the invention relates to a recording medium, such as a high-density and/or read-only recording medium such as a BD-ROM, comprising an array-coded array of wobble pits formed at intervals in a distributed manner. Copy protection information, the present invention also relates to methods and apparatuses for forming, recording and reproducing data on a recording medium.

In an exemplary embodiment, the present invention relates to a recording medium, such as a high-density and/or read-only recording medium such as a BD-ROM, comprising pits formed along a track in which data is recorded, The data contains copy protection information for encryption and/or decryption, wherein the pits formed in some parts of the track are shifted from the center of the track to the left and/or right to form spaced or alternating wobble pits, wherein Key information for encryption and/or decryption is encoded as offsets of said pits displaced from the center of the track. The invention also relates to methods and apparatus for forming, recording and reproducing data on a recording medium.

In an exemplary embodiment, the present invention relates to a method of forming a recording medium such as a high-density and/or read-only recording medium (such as a BD-ROM), the method comprising the step of forming pits along a track in which data is recorded, the Data containing copy protection information for encryption and/or decryption, wherein pits formed in parts of the track are shifted from the center of the track to the left and/or right to form spaced or alternately jittered pits, wherein for Encrypted and/or decrypted key information is encoded as an offset of said pits displaced from the center of the track.

In an exemplary embodiment, the present invention relates to a method of forming a recording medium, such as a high-density and/or read-only recording medium (such as a BD-ROM), comprising the step of utilizing data recorded in pits formed along a track, the Data containing copy protection information for encryption and/or decryption, wherein the pits formed in some parts of the track are shifted from the center of the track to the left and/or right to form spaced or alternating wobble pits, wherein for Encrypted and/or decrypted key information is encoded as an offset of said pits displaced from the center of the track.

In an exemplary embodiment, the present invention relates to a method of forming a recording medium such as a high-density and/or read-only recording medium (such as a BD-ROM), which includes the step of recording data in pits formed along a track, the data Contains copy protection information for encryption and/or decryption, wherein the pits formed in some parts of the track are shifted from the center of the track to the left and/or right to form spaced or alternating wobble pits, wherein for encryption and/or decrypted key information is encoded as an offset of said pits displaced from the center of the track.

Description of drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the specification explain the principle of the invention.

In the picture:

Figures 1A and 1B illustrate the structure of an existing BD-RE;

FIG. 2 illustrates a high frequency modulation (HFM) trench formed in a PIC region of a BD-RE;

Figure 3 illustrates the areas allocated to a BD-ROM;

4A-4F illustrate several formats of data recorded in the PIC area of a BD-ROM according to an exemplary embodiment of the present invention;

Figure 5 illustrates an example of an exemplary embodiment of the invention in which copy protection information is encoded by an array of wobbled pits formed at intervals;

FIG. 6 illustrates a data structure of a physical cluster of a BD-ROM in an exemplary embodiment of the present invention;

FIG. 7 illustrates information encoded in dithered pits and a circuit for detecting jitter information according to an exemplary embodiment of the present invention;

FIG. 8 illustrates information encoded in linear pits and a circuit for detecting gutter information according to an exemplary embodiment of the present invention;

FIG. 9 illustrates disc information fields recorded on a BD-ROM according to an exemplary embodiment of the present invention;

FIG. 10 illustrates disc type information recorded on the BCA based on an exemplary embodiment of the present invention; and

FIG. 11 illustrates a system block diagram of an optical disk reproducing apparatus capable of reproducing a BD-ROM according to an exemplary embodiment of the present invention.

Detailed ways

In order that the present invention may be more fully understood, exemplary embodiments thereof will be described with reference to the accompanying drawings.

Referring to FIG. 3, as described above, a BD-ROM according to an exemplary embodiment of the present invention may include an inner area, a clamp area, a transition area, an information area, and a margin area. As shown in FIG. 4A, DII, such as the disc serial number and copy protection information recorded in the BCA, is copied to the PIC area contained in the information area at least once. The copy protection information may be a key value required for decrypting encrypted A/V stream main data recorded in the data area.

As shown in FIG. 4B, the copy protection information may not be recorded in the BCA, but only in the PIC area. This copy protection information may also be called "ROM flag", and includes an additional flag (CPI flag) indicating whether to record the copy protection information.

As shown in FIG. 4C, the information contained in the PIC may be recorded partly as wobbled pits (or sawtooth pits) and partly as linear pits. Main data may be recorded on the data area in the form of linear pits.

In an exemplary embodiment, the PIC area may contain 2,720 data clusters. The first cluster may contain disc information recorded in wobbled pits by bi-phase modulation. Other clusters may contain disc information recorded as linear pits modulated by 17PP and copy protection information with a 64KB size ECC block, for example disc information recorded as wobble pits can be detected by the push-pull signal detection method, while recorded as linear pits The copy protection information of the pits can be detected by an RF signal detection method. Push-pull signals generally have lower frequency components than RF signals.

In an exemplary embodiment, the DII additionally copied to the PIC area may be encoded with wobble pits to prevent detection by RF signal detection methods.

Figures 4D, 4E, and 4F illustrate several different exemplary data formats. In FIG. 4D, DII is encoded as wobble pits, and disc information is encoded as linear pits. In FIG. 4E, DII and a part of disc information are encoded as wobble pits. In Fig. 4F, both DII and disc information are encoded as wobble pits.

In one example, copy protection information (ROM marks) may be recorded in wobbled pits formed at intervals to prevent them from being easily detected by common detection methods, while data recorded in the data area is formed by linear pits.

Fig. 5 shows an exemplary embodiment of the present invention in which copy protection information is encoded by an array of wobbled pits formed at intervals.

As shown in Figure 5, in order to ensure security or robustness, it is preferable to record spaced wobbled pit structures rather than continuous wobbled pits on an area so that the copy protection information cannot be easily detected by normal detection methods.

In FIG. 5 , the straight pit array (An) and the jitter pit array (Bn) are alternately formed, and the length of the straight pit array is longer than that of the jitter pit array to obtain different durations. Therefore, the wobble pits in which the copy protection information is encoded are regarded as noise signals by the usual detection methods.

All linear pit arrays may have the same length, or all wobble pit arrays may have the same length. If the pit arrays are of unequal length, ie if An≠Am (n≠m) and Bn≠Bm (n≠m), the occurrence of the dithered pit array is aperiodic. This enhances the confidentiality of copy protected information, since the probability of specific information being encoded with wobble pits becomes lower.

The copy protection information can be encoded in wobble pits using a number of different other modulation methods. Analog modulation methods include amplitude modulation (AM), frequency modulation (FM), while digital modulation methods include pulse code modulation (PCM), minimum shift keying (MSK), and binary phase shift keying (BPSK).

Although the same modulation technique can be applied to all wobbled pit arrays, the wobbled pit arrays can be encoded by different kinds of modulation techniques to enhance the secrecy of the copy protection information. For example, in FIG. 5, the first wobbled pit array B1 may be encoded by amplitude modulation, while the second wobbled pit array B2 may be encoded by frequency modulation, and so on.

To reduce possible data reading errors, in an exemplary embodiment, the same data may be repeatedly encoded in an array of wobbled pits.

And, combining the wobbled pit area and the non-jittered pit area, or combining a plurality of areas, then the bit for copy protection can be detected. For example, the recording area of the wobble pit corresponding to the data bit is dispersedly recorded in several areas, and the wobble pit is formed so that the jitter amplitude is small, so that by detecting a low-level push-pull signal, and The signals are combined to detect the bit.

In an exemplary embodiment, the size of the copy protection information does not exceed 128 bits, but can be increased to 1 KB if header information and redundant data for ECC are appended.

As shown in FIG. 6, as an example, the size of a physical cluster of a BD-ROM may be 64 KB and include 16 address units. Each data unit may further include 31 data frames. Therefore, if the first data frame (data frame #0) of each address unit is encoded with wobble pits to record bytes of copy protection information, a physical cluster can store up to 16 bytes.

Therefore, copy protection information with a size of 1K can be contained in 64 clusters. If an exemplary PIC area contains 2,720 clusters, the PIC area will have enough space to store copy protection information at least once. Furthermore, copy protection information can be recorded more than once in the PIC area to enhance the reliability of recorded data.

In other exemplary embodiments, data frames other than the first data frame of each address unit may also be formed as wobble pits, or more than two data frames of each address unit may be formed as wobble pits, Encoded copy protection information.

Instead of encoding the copy protection information in a fixed data frame in each data unit, the information can also be encoded in an arbitrary data frame in each address unit. In this exemplary embodiment, the generation of the low-frequency signal created by the jitter pits is non-periodic, and therefore, as described above, the secrecy of this information can be enhanced.

Copy protection information can also be recorded as linear pits. In this exemplary embodiment, the copy protection information may be encrypted before being recorded, and a key value for decrypting the encrypted copy protection information may be encoded in wobble pits, thereby preventing illegal copying of related content.

Figure 7 illustrates optical disc information encoded in wobble pits by bi-phase modulation, and a circuit for detecting this information, where an example value of "0101" is bi-phase modulated, e.g., bi-phase modulated HFM groove encoded, but also encoded in dithered pits. In this example, data bits are recorded as marks and spaces of length 36T, which includes 6 3T marks. The 6 pits representing "1" and the 6 pits representing "0" are displaced from the center of the track in opposite directions.

As shown in FIG. 7 , the structure obtained by bi-phase modulation is different from that shown in FIG. 2 . That is, the method in FIG. 2 has bits with a value of 0 represented by transitions occurring at the beginning of the bit cell, and bits with a value of 1 represented by transitions occurring at the beginning and middle of the bit cell. On the other hand, the method in FIG. 7 has bits with a value of 0 represented by transitions occurring at the beginning of the low level and in the middle of the high level, while bits with a value of 1 are represented by transitions occurring in the opposite direction. The combination of bits consists of data for detecting information recorded as wobble pits. This information may be copy protection information, that is, a key value for decrypting the main data recorded in the data area of the recording medium as shown in FIGS. 4A to 4F.

That is, the wobble pit data can be reproduced or detected only when the biphase modulation data modulated by HFM is normally detected or reproduced. Also, reproduction or decryption of the main data is possible only when the wobble pit data for copy protection is reproduced or detected using normally detected or reproduced biphase modulation data.

Meanwhile, if information is encoded in pits, continuous pits having the same length will not be allowed to appear, and therefore, pits whose lengths are different from each other will appear sequentially. In this exemplary embodiment, the position of the data bits may be shifted at intervals of 18T to encode the data in wobbled pits.

The laser beam reflected by the wobble pits is converted into an electrical signal by the optical detection means 13-16.

This electrical signal can be amplified by a push-pull circuit, wherein the signals Ea+Eb and Ec+Ed are individually amplified by the amplifying circuits 10, 11, respectively, and then a differential signal ((Ea +Eb)-(Ec+Ed)). Data encoded in wobbled pits is obtained by comparing the differential signal 501 with a preset level.

Similarly, DII and/or disc information (or other information) encoded in wobble pits can be obtained by a push-pull circuit for generating tracking error signals without additional error correction and demodulation operations.

When accessing BCA of BD-ROM. If an error occurs due to scratches or other deformation of the disc, the DII can be retrieved from the PIC area, and the retrieved information can be used to reproduce the information recorded on the disc. Therefore, the main data recorded in the data area can be decrypted using the decryption key included in the DII recorded in the PIC area.

Since the data encoded in wobble pits such as DII and/or disc information is not obtained by demodulation, when the content in the BD-ROM is copied to another rewritable medium, the above information is not copied, so the copy Encrypted data to rewritable media cannot be decrypted, thereby preventing illegal copying of BD-ROM contents.

The disc information and copy protection information encoded in linear pits shown in FIGS. 4C to 4E can be detected by the circuit described in FIG. 8 .

The laser beams reflected by the linear pits are converted into electrical signals by optical detectors 13-16, and the electrical signals (Ea, Eb, Ec, and Ed) are amplified and added by one or more summing amplifiers 20, 21, and 22 . The RF signal Ea+Eb+Ec+Ed is converted into a binary pulse train by the RF unit 23 as an output value of the adding amplifier 22, and converted into digital data by a clock signal synchronized with the binary signal. The original disc information and copy protection information are obtained from the digital data through ECC and demodulator 24 .

Disc information and copy protection information encoded in linear pits can be read in the same manner as the main data recorded in the data area.

The disc information may include disc information ID, disc information format, disc type ID, and disc capacity/version, etc., as shown in FIG. 9 . An exemplary 3-byte disc type ID for indicating the disc type may be recorded in the BCA as 2-bit data, as shown in FIG. 10 .

For example, if the 2-bit data is 00b, the corresponding disc is BD-RE. If the data is 01b, the corresponding disc is a recordable disc BD-R. If the data is 10b, the corresponding optical disc is a BD-ROM.

The size of the disc information and a flag indicating whether it is the last disc information may be allocated to the reserved field of the disc information.

FIG. 11 illustrates a block diagram of a general-purpose optical disc reproducing apparatus, which includes an optical pickup 30 , a video disc playback (VDP) system 31 , and a D/A converter 32 . Once the disc is loaded, the VDP system 31 for performing signal processing and servo control detects the disc type information recorded on the BCA, and performs an appropriate servo initialization operation according to the detected disc type.

The VDP system 31 can detect disc information encoded in wobble pits from the push-pull signal, for example, key data to encrypt and/or decrypt main data of the data area in the PIC area.

Where the size of the disc information and a flag indicating whether it is the last disc information are assigned to the reserved field, the disc information and the copy protection information recorded in the PIC area can be more accurately detected by using the information of the reserved field.

In another exemplary embodiment, a transition area for respectively detecting disc information and copy protection information may be allocated to the PIC area.

As shown in FIG. 7, if the copy protection information is encrypted and encoded with linear pits, the VDP system 31 detects the decryption key encoded with wobbled pits in the PIC area to decipher the copy read from the linear pits. The protected information is decrypted, and the decrypted copy protected information is stored. When the main data recorded in the data area is reproduced, the main data is decrypted using the stored copy protection information.

Thus, the high-density, read-only, and/or optical disc and the optical disc information recording method according to the exemplary embodiment of the present invention can repeatedly record important information necessary for protecting the recorded content on the optical disc, and encode the information with wobble pits , thereby enhancing data reliability and preventing illegal copying of the contents of the disc.

While certain exemplary embodiments of the present invention are disclosed herein, it is to be noted that the present invention may also be embodied in other forms without departing from the spirit or essential characteristics of the invention. Accordingly, the exemplary embodiments are to be considered in any respect as illustrative rather than restrictive, the scope of the invention being indicated by the appended claims and equivalents thereto. All changes within the meaning and range should be considered to be included within the scope of the present invention.

Claims (26)

1. recording medium that comprises the data of record, it comprises:

Pit along the track formation that records data in it; described data comprise and are used to the copy protection information encrypting and/or decipher; the pit that wherein is formed at the some parts of described track is displaced to the left side and/or the right from orbit centre; to form at interval or the wobbled pits that replaces; wherein, the key information that is used to encrypt and/or decipher is encoded as from the offset form of the described pit of orbit centre displacement.

2. recording medium as claimed in claim 1, wherein, described wobbled pits is arranged in the introducing district of the block of information of described recording medium.

3. recording medium as claimed in claim 2, wherein, described wobbled pits is arranged in the permanent information and control (PIC) data field of the block of information of described recording medium.

4. recording medium as claimed in claim 1, wherein, described wobbled pits is arranged in the burst of the block of information of described recording medium and cuts off district (BCA), and this BCA comprises optical disc types information.

5. recording medium as claimed in claim 1, wherein, described data are encoded as the offset form of described wobbled pits.

6. recording medium as claimed in claim 5, wherein, described offset form has the bit value through bi-phase modulated.

7. recording medium as claimed in claim 1, wherein, described data comprise the information of relevant described recording medium, this information comprises the type of described recording medium.

8. recording medium as claimed in claim 1, wherein, described data comprise the decryption information that is used to decipher the encrypted content that writes down on the described recording medium.

9. recording medium as claimed in claim 1, wherein, described data further comprise at least one in sequence number, optical disc information and the disc important information of described recording medium.

10. recording medium as claimed in claim 1, wherein, described copy protection information is the copy protection sign.

11. recording medium as claimed in claim 9, wherein, described optical disc information and described disc important information can be by with the wobbled pits records.

12. recording medium as claimed in claim 11, wherein, described wobbled pits is detected by push-pull signal.

13. recording medium as claimed in claim 9, wherein, described optical disc information can be with the straight pit record.

14 recording mediums as claimed in claim 13, wherein, described straight pit is detected by the RF input.

15. recording medium as claimed in claim 1, wherein, described record data are by with the straight pit record, and described straight pit is detected by the RF input.

16. recording medium as claimed in claim 3, wherein, the described information that comprises the relevant described recording medium of described recording medium type is recorded as the straight pit that is arranged in described PIC district through modulation, and wherein, this straight pit is not from described orbit centre displacement.

17. recording medium as claimed in claim 3, wherein, this is used for deciphering the decryption information that is recorded in the enciphered data on the described recording medium and is recorded as the straight pit that is positioned at described PIC district through modulation.

18. recording medium as claimed in claim 17, wherein, this decryption key information that is used to decipher described encrypted decryption information is encoded as from the offset form of the described pit of described orbit centre displacement.

19. recording medium as claimed in claim 1, wherein, this array from the described pit of orbit centre displacement forms on more than two positions at interval.

20. recording medium as claimed in claim 19, wherein, should be from the length of the straight pit array between the array of the described pit of orbit centre displacement greater than length from the described pit array of orbit centre displacement.

21. recording medium as claimed in claim 19, wherein, each is all inequality from the length of the described pit array of orbit centre displacement.

22. recording medium as claimed in claim 21, wherein, the length of the straight pit array between the array of the pit of each described displacement is all inequality.

23. a method that is used to form recording medium, it comprises the steps:

Form the pit that forms along the track that wherein records data; described data comprise and are used to the copy protection information encrypting and/or decipher; the pit that wherein is formed at the some parts of described track is displaced to the left side and/or the right from orbit centre; to form at interval or the wobbled pits that replaces; wherein, the key information that is used to encrypt and/or decipher is encoded as from the offset form of the described pit of orbit centre displacement.

24. one kind is used for from the recording medium method of reproducing data, it comprises the steps:

The data that utilization is write down with the pit that forms along track; described data comprise and are used to the copy protection information encrypting and/or decipher; the pit that wherein is formed at the some parts of described track is displaced to the left side and/or the right from orbit centre; to form at interval or the wobbled pits that replaces; wherein, the key information that is used to encrypt and/or decipher is encoded as from the offset form of the described pit of orbit centre displacement.

25. a method that is used at the recording medium identifying recording layer, it comprises the steps:

With the pit record data that form along track; described data comprise and are used to the copy protection information encrypting and/or decipher; the pit that wherein is formed at the some parts of described track is displaced to the left side and/or the right from orbit centre; to form at interval or the wobbled pits that replaces; wherein, the key information that is used to encrypt and/or decipher is encoded as from the offset form of the described pit of orbit centre displacement.

26. device that is used for reproducing data from recording medium; the pit that described device utilization forms along the track that wherein records data; described data comprise and are used to the copy protection information encrypting and/or decipher; the pit that wherein is formed at the some parts of described track is displaced to the left side and/or the right from orbit centre; to form at interval or the wobbled pits that replaces; wherein, the key information that is used to encrypt and/or decipher is encoded as from the offset form of the described pit of orbit centre displacement.

Images