JP2005071428A - Optical disk and optical disk recording and reproducing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To speedily and accurately decide the kind of an optical disk. <P>SOLUTION: In a bar-code area a2 of the optical disk 10, information representing the kind of the optical disk is previously recorded as a bar code. A control part 12 of an optical disk recording and reproducing apparatus reads the disk kind information out of the bar-code area a2 of the optical disk 10 and decides the kind of the optical disk 10 from the read disk kind information and a previously stored correspondence table. Consequently, the kind of the optical disk 10 is discriminated first and processing corresponding to the optical disk can speedily be performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a technique for determining the type of an optical disc loaded in an optical disc recording / reproducing apparatus.

  Optical disks include CD (Compact Disk) and DVD (Digital Versatile Disk), as well as blue laser disks developed as next-generation optical disks. These optical discs have standards as shown in Table 1 for each type.

近年になって、このような複数種別の光ディスクのいずれをも再生又は記録することが可能な光ディスク記録再生装置が実用化されつつある。この種の装置においては、まず、装填された光ディスクの種別を判別し、判別した種別に応じてサーボ回路の動作条件を適宜制御しながら光ディスクに対する再生処理或いは記録処理を実行するようになっている。

In recent years, an optical disc recording / reproducing apparatus capable of reproducing or recording any of the plurality of types of optical discs has been put into practical use. In this type of apparatus, first, the type of the loaded optical disk is determined, and the reproducing process or the recording process for the optical disk is executed while appropriately controlling the operating conditions of the servo circuit according to the determined type. .

A general method for discriminating the type of optical disc is to attempt to read information from the optical disc while sequentially switching the laser light from the long wavelength side to the short wavelength side, and based on the wavelength of the laser light at the time when the information reading was successful, The type is determined. More specifically, the optical disc recording / reproducing apparatus first attempts to read information by performing a focus search using a laser beam having a wavelength of 780 nm with respect to the loaded optical disc, and if that is not possible, the focus is switched to the laser beam having a wavelength of 650 nm. The search and information reading are attempted, and if that is not possible, the focus search and information reading are attempted by switching to a laser beam of 430 nm. Therefore, when a blue laser disc capable of reading information only by a laser beam having a wavelength of around 430 nm is loaded, the optical disc storage / reproducing apparatus needs to try focus search and information reading three times in total. This is very cumbersome and takes a considerable amount of time.
On the other hand, when reading information while switching the laser light from the short wavelength side to the long wavelength side, the reflected light from the optical disk (CD-R, etc.) including the dye film is detected. There is a problem that it is difficult to adopt, so it is impossible to adopt such a method.

  In view of such a problem, Patent Document 1 proposes to determine the type of an optical disc based on the detection time of a focus error signal detected during a focus search. Specifically, during the initial focus search for the optical disc, a focus error signal represented by an S-curve is detected, but the second S-curve that appears next from the S-curve that appears corresponding to the substrate surface. The disc type is discriminated based on the time until the curve.

Japanese Patent Laid-Open No. 10-134490

  The discrimination method described in Patent Document 1 is based on the principle that the longer the distance from the substrate surface to the recording layer (that is, the greater the substrate thickness T), the longer it takes for the second S-curve to appear. Is. Therefore, if the size of the substrate thickness T is different for each type of optical disk, the type of each optical disk should be able to be accurately determined.

However, as shown in Table 1, since both DVD and AOD (Advanced Optical Disk) have a substrate thickness T = 0.6 mm, the technique described in Patent Document 1 can accurately distinguish both of them. Can not. Therefore, in order to discriminate between DVD and AOD, it must be used in combination with the method of repeatedly reading information while switching the wavelength of the laser light as described above. This still takes time to discriminate the optical disk.
The present invention has been made in view of such a background, and an object of the present invention is to quickly and accurately determine the type of an optical disc without complicated processing.

  In order to solve the above-described problems, the present invention provides an optical disc in which disc type information representing the type of the optical disc is recorded. As a result, information indicating the type of the optical disk can be directly read from the optical disk, so that the type of the optical disk can be determined quickly and accurately. The information indicating the type of the optical disc may be an identifier that can uniquely identify the type of the optical disc, or information that makes it possible to determine the type by representing the structure of the optical disc. It may be information that makes it possible to distinguish the type by expressing the wavelength of light used for reproduction or recording. The disc type information is preferably recorded in a predetermined position of the optical disc, that is, in an area where information is first read out by the optical disc recording / reproducing apparatus. Specifically, the position is a predetermined distance from the center of the optical disk and a position at a predetermined depth from the substrate surface of the optical disk. The disc type information can be recorded by any means (for example, a barcode) that can be read by the optical disc recording / reproducing apparatus.

  In a preferred aspect of the present invention, information recorded in the information recording area of the optical disc may be additionally recorded together with the above-described disc type information. In this way, the optical disc recording / reproducing apparatus can simultaneously read the additional information as described above when reading the disc type information, so that the already read information content is read from the information recording area. There is no need for this, and it can be expected to speed up processing.

  Further, the present invention provides a reading means for reading information from a predetermined area of the optical disc, and when the read information is disc type information indicating the type of the optical disc, a recording process or reproduction for the optical disc based on the disc type information. Optical disc recording / reproducing apparatus light provided with a control means for controlling processing is provided. This reading means may be an optical reading means such as an optical pickup originally provided in the optical disk recording / reproducing apparatus, or may be a reading means different from this optical reading means.

  According to the present invention, since the information indicating the type of the optical disk can be read directly from the optical disk, the type can be quickly and accurately determined.

Next, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a structure of an optical disc 10 according to the embodiment. The optical disk 10 is a CD, DVD, blue laser disk, or the like, and is a read-only type in which all data has already been written at the time of shipment, a type that can be recorded only once (Recordable), or a type that can be recorded multiple times ( Rewritable). Each of these optical discs 10 is formed by laminating a substrate, a recording layer, a protective layer, and the like. A center hole h having a predetermined diameter is provided at the center of the optical disc 10, and a clamp area a1, a barcode area a2, and an information recording area a3 are formed concentrically around the center hole h. In the barcode area a2, a defect is provided in a metal film disposed at a predetermined depth t (for example, t = 0.6 mm) from a substrate surface having a predetermined radius r (for example, r = 22 mm) from the center of the optical disk. An eccentric circular bar code BC is formed. The information recording area a3 includes a lead-in area, a data area, a lead-out area (all not shown), and the like. In the recording layer formed at a position of the depth (substrate thickness) T from the substrate surface of the information recording area a3, data indicating audio, video, or a computer program is recorded by a pit row formed in a spiral shape. It has come to be.

FIG. 2 is a diagram showing an information format of the barcode area a2.
As shown in FIG. 2, the barcode area a2 of the optical disc 10 has a recording capacity of 23 bytes in total, and information called "disc type information" is recorded in the recording area of 3 bytes, and the remaining 20 Information called “disc type additional information” is recorded in the recording area for bytes. The disc type information is information indicating the type of the optical disc 10 and is an identifier uniquely assigned to the type of the optical disc 10 in this embodiment. The disc type information is composed of a character string of 3 characters. Since this character string is represented by an ASCII code, the data amount is 3 bytes for 3 characters. Table 2 shows the correspondence between the character string and the optical disc type.

表２における「スタンプＣＤ」、「スタンプBlu-ray」及び「スタンプAOD」とは、出荷時には既にデータが書き込まれている再生専用の光ディスクを意味している。また、「Ｔ」とは基板厚を意味している。光ディスク１０の再生又は記録を行うディスク記録再生装置は、上記対応表を予め記憶しておき、光ディスク１０のバーコード領域ａ２からバーコードを読み取ることによって、装填された光ディスクの種別を判別することができる。例えばディスク種別情報として「ＣＤ０」を読み取ったときには、装填された光ディスクは「スタンプＣＤ」であると判別する、と行った具合である。

“Stamp CD”, “Stamp Blu-ray”, and “Stamp AOD” in Table 2 mean a read-only optical disc on which data has already been written at the time of shipment. “T” means the substrate thickness. A disc recording / reproducing apparatus for reproducing or recording the optical disc 10 stores the correspondence table in advance and reads the barcode from the barcode area a2 of the optical disc 10 to determine the type of the loaded optical disc. it can. For example, when “CD0” is read as the disc type information, it is determined that the loaded optical disc is “stamp CD”.

Next, the “disc type additional information” shown in FIG. 2 will be described.
The disc type additional information is usually a part of information recorded in the lead-in area of the optical disc 10. A general optical disc recording / reproducing apparatus first starts reading information after focusing an optical pickup on the recording layer of the information recording area a3 of the optical disc. However, since the optical disc recording / reproducing apparatus of this embodiment first reads the barcode from the barcode area a2 before reading the information from the information recording area a3, the number of the optical disk recording / reproducing apparatus is simultaneously adjusted according to the reading timing. It is convenient and convenient to read such useful information from the barcode area a2. This is because part of the information in the lead-in area can be acquired at the time the barcode is read, so it is not necessary to read the information from the lead-in area and the processing can be speeded up. is there. Since this disc type additional information is different information depending on the type of the optical disc 10, the content will be described for each type.

(1) In the case of a stamp CD FIG. 3A is a diagram showing a format of disc type additional information of the stamp CD.
As shown in FIG. 3A, the first 10 bytes of the disc type additional information are points A0, A1 and ATA (Absolute Time in Pregroove) information recorded in the lead-in area of the first session. It is composed of information (a total of 9 bytes) indicating PTIME of A2 and an ASCII code “0” for filling the remaining 1 byte. The next 10 bytes indicate information (9 bytes in total) indicating PTIME of points A0, A1, and A2 in the ATIP information recorded in the lead-in area of the last session, and the total number of sessions on the optical disc 10. It consists of numbers (1 byte).

  As is well known, PTIME includes three pieces of information: PMIN, PSEC, and PFRAME. PMIN at point A0 represents the first track number in the session. PMIN at the point A1 represents the last track number in the session. The PTIME at the point A2 represents the start time of the lead-out area during the session. As an example, in the case of ATIP information as shown in FIG. 4 (A), the number indicated by PMIN (“PMSF =” in the figure) at the point A0 (“POINT = a0h” in the figure) of the first session. Since the leftmost number) is “1”, the first track number in the first session is 1. Next, since the PMIN at the point A1 (“POINT = a1h” in the figure) is “12”, the last track number in the first session is 12. Since PTIME (the number indicated by “PMSF =” in the figure) at the point A2 (“POINT = a2h” in the figure) is “46: 4: 25”, the start of the lead-out area of the first session The time is 46 minutes 4 seconds 25 frames.

  Such a definition is the same for the second session, and information of a portion surrounded by a wavy line in FIG. 4A is recorded as additional disc information in the barcode area a2 by the ASCII code. In the example shown in FIG. 4A, since the number of sessions is 2, “2” indicating the total number of sessions is recorded as additional disk type information by the ASCII code.

(2) CD-R
FIG. 3B is a diagram showing a format of CD-R disc type additional information.
As the CD-R disc type additional information, first special information (ATIP special information 1) to third special information (ATIP special information 3) of ATIP information in the lead-in area is recorded. As an example, information of a portion surrounded by a wavy line in FIG. 4B is recorded as disc additional information in the barcode area a2 by the ASCII code. Since each of these special information is 3 bytes, the remaining 20 (bytes) −3 (bytes) × 3 = 11 (bytes) recording area is filled with 11 ASCII codes “0”.

(3) CD-RW
FIG. 3C is a diagram showing a format of disc type additional information of CD-RW.
The CD-RW disc type additional information includes first special information (ATIP special information 1) to third special information (ATIP special information 3) and first additional information (ATIP additional information 1) to third in the ATIP information of the lead-in area. Additional information (ATIP additional information3) is recorded. As an example, information of a portion surrounded by a wavy line in FIG. 4C is recorded as additional disk information in the barcode area a2 by the ASCII code. Since these special information and additional information are each 3 bytes, the area of 20 (bytes) −3 (bytes) × 6 = 2 (bytes) is filled with two ASCII codes “0”.

(4) In the case of DVD FIG. 5A is a diagram showing data described in an area called a control data zone of a DVD defined by ANSI X3T10 MMC4 Revision2A. Information of a total of 16 bytes from “BookType” of Byte 0 to “End Physical Sector Number in Layer 0” of Byte 15 shown in FIG. 5A is recorded in the barcode area a2 as additional disc type information. In this case, an area of 20 (bytes) −16 (bytes) = 4 (bytes) is filled with four ASCII codes “0”.
Here, FIG. 5B is a correspondence diagram showing the description contents of “BookType” and its meaning. For example, if the description content of “BookType” is “0000b”, it means that the optical disk is “DVD-ROM”, and if “0001b”, it means “DVD-RAM”. “0010b” means “DVD-R”, “0011b” means “DVD-RW”, and “1001b” means “DVD + RW”. "1010b" means "DVD + R". Therefore, based on whether “BookType” is the description content described above, whether it is a stamp DVD, a DVD-R or DVD + R that can be recorded only once, or a rewritable DVD-RW or DVD + RW. It is possible to know the detailed disc type.
For AOD and Blu-ray, based on the same viewpoint as the above example, information that is considered to be useful if it is first read from the barcode area a2 may be appropriately added as disc type additional information.

Next, an optical disk recording / reproducing apparatus that records or reproduces the optical disk 10 will be described.
FIG. 6 is a diagram showing a configuration of the optical disc recording / reproducing apparatus 100 according to the present embodiment. The servo circuit 11 performs rotation control of the spindle motor 13, focus control, tracking control, track jump control, and feed control of the optical pickup 14 under instructions from the control unit 12. The storage unit 17 stores the position of the barcode area a2 on the optical disc 10 (here, radius r = 22 mm and depth t = 0.6 mm from the substrate surface), a correspondence table of disc type information as described above, and a later-described table. A procedure (program) for performing the operation is stored. When data recording processing is performed on the optical disc 10, a recording signal is input to a recording signal correction circuit 15 by a recording signal generation circuit (not shown), and the recording signal time axis (irradiation start / end timing) is recorded in the recording signal correction circuit 15. And irradiation time) will be corrected. The laser generation circuit 16 supplies laser light to the optical pickup 14 in accordance with the recording signal that has been time-axis-corrected under the instruction from the control unit 12, whereby data is recorded on the optical disk 10. Yes. When executing data reproduction processing on the optical disc 10, the control unit 12 controls the laser generation circuit 16 to irradiate the optical disc 10 with laser light from the optical pickup 14. Then, the control unit 12 acquires information represented by the barcode from the barcode area a2 based on the light reception signal detected by the optical pickup 14, or the information represented by the pit string from the information recording area a3. To get.

Next, the operation of the optical disc recording / reproducing apparatus 100 will be described with reference to the flow shown in FIG.
When the control unit 12 detects that the optical disc 10 is loaded in the optical disc recording / reproducing apparatus 100 (step S11; Yes), the control unit 12 sends an instruction to the servo circuit 11 to store the barcode area a2 stored in the storage unit 17. The optical pickup 14 is moved to a radial position (here, radius r = 22 mm) (step S12).

  Next, the control unit 12 sends an instruction to the servo circuit 11 to focus the optical pickup 14 at a position at a depth t (here, t = 0.6 mm) from the substrate surface stored in the storage unit 17. (Step S13). Further, the control unit 12 controls the servo circuit 11 to rotate the spindle motor 13 to start reading the barcode, and tries to acquire the disk type information and the disk type additional information (step S14). Next, the control unit 12 determines the type of the optical disc 10 based on the read disc type information and the correspondence table stored in the storage unit 17 (step S15).

  Here, if the read disc type information is any one of “CD0”, “CD1”, and “CD2”, the control unit 12 indicates that the loaded optical disc 10 is a CD (or CD-R or CD-RW). ) (Step S15; CD), and the process proceeds to a process corresponding to the CD (or CD-R or CD-RW) (step S16). That is, the control unit 12 controls the servo circuit 11 to irradiate the recording layer having the substrate thickness T = 1.2 mm with the laser beam having a wavelength of 780 nm from the optical pickup 14 and irradiate it, and has already read out the disc type additional information. Based on this, processing such as information recording or reproduction is performed.

  If the disc type information read in step S14 is “DVD”, the control unit 12 determines that the loaded optical disc 10 is a DVD (step S15; DVD), and shifts to processing corresponding to the DVD. (Step S17). That is, the control unit 12 controls the servo circuit 11 to irradiate the recording layer having the substrate thickness T = 0.6 mm with the laser light having a wavelength of 650 to 660 nm from the optical pickup 14 and irradiate the laser type. Processing such as recording or reproduction of information is performed based on the additional information.

  If the disc type information read in step S14 is any one of “BLA”, “BLB”, and “BLC”, the controller 12 determines that the loaded optical disc 10 is AOD (or AOD-R or AOD). -RW) (step S15; Blue (T = 0.6)), and the process proceeds to processing according to AOD (or AOD-R or AOD-RW) (step S18). That is, the control unit 12 controls the servo circuit 11 to irradiate the recording layer having the substrate thickness T = 0.6 mm with the laser beam having a wavelength of 430 nm from the optical pickup 14 and irradiate the information, and the disc type additional information that has already been read. Based on this, processing such as information recording or reproduction is performed.

  If the disc type information read in step S14 is any one of “BL1”, “BL2”, and “BL3”, the controller 12 determines that the loaded optical disc 10 is Blu-Ray (or Blu-ray). -R or Blu-ray-RW) (step S15; Blue (T = 0.1)) and processing according to Blu-Ray (or Blu-ray-R to Blu-ray-RW) Transition is made (step S19). That is, the control unit 12 controls the servo circuit 11 to irradiate the recording layer having the substrate thickness T = 0.1 mm with the laser beam having a wavelength of 430 nm from the optical pickup 14 and irradiate the information, and the disc type additional information already read out Based on this, processing such as information recording or reproduction is performed.

  If the disc type information cannot be read in step S14, the controller 12 determines that the disc type information is not recorded on the loaded optical disc (step S15; no information). The process proceeds to the disc type discrimination process similar to (step S20). Then, when the disc type can be determined, processing such as recording or reproduction of information according to the type is performed.

As described above, in the present embodiment, the disc type information indicating the type of the optical disc 10 is recorded in advance in the barcode area a2 of the optical disc 10, and the optical disc recording / reproducing apparatus 100 is loaded with the optical disc 10. First, the disc type information is read from the barcode area a2. In this way, the optical disc recording / reproducing apparatus 100 can directly acquire information representing the type of the optical disc 10 from the optical disc 10, so that the type can be determined accurately and quickly.
Furthermore, in the present embodiment, information originally recorded in the lead-in area is recorded in the barcode area a2 as disc type additional information. When reading the disc type information from the barcode area a2, the optical disc recording / reproducing apparatus 100 also reads the disc type additional information at the same time. In this way, the optical disc recording / reproducing apparatus 100 does not need to read the content already read out as additional disc type information from the lead-in area, so that the processing speed can be expected.

The present invention is not limited to the contents exemplified in the above embodiment, and the following modifications are possible.
In the embodiment, the barcode is formed at a position where the depth t = 0.6 mm from the substrate surface. However, the depth t may be larger or smaller than 0.6 mm. Further, a barcode may be formed on the substrate surface (that is, t = 0). However, there is an advantage that it is easier to focus the optical pickup 14 when the barcode is formed at a certain depth in the substrate than when the barcode is formed on the substrate surface. Similarly, the radial position r of the barcode area a2 can be set to an appropriate position.

  The disc type information recorded in the barcode area a2 is not limited to that exemplified in the embodiment, but may be any information that can quickly discriminate the type of the optical disc. For example, if the information indicating the structure of the optical disk (substrate thickness T, track pitch, etc.) and the information indicating the wavelength of light used for recording or reproduction on the optical disk can be known, the type of the optical disk can be determined immediately. Such information may be recorded as disc type information. For example, if the substrate thickness T = 12, the number “12” is recorded as the disc type information, and if the optimum laser light wavelength is 780 nm, the number “780” is recorded. Note that this type of information may be omitted as appropriate. For example, if the wavelength is 780 nm, the recording is omitted as “7” or “78”.

  In the embodiment, the disc type information and the disc type additional information are recorded using the barcode. However, the present invention is not limited to this, and the disc type information and the disc type additional information may be recorded by a mechanism that can be read by the optical disc recording / reproducing apparatus 100. Further, in the embodiment, the barcode is read by using the optical pickup 14 originally provided in the optical disc recording / reproducing apparatus 100. However, the present invention is not limited to this, and an apparatus dedicated to barcode reading other than the optical pickup is provided. It may be.

1 is a schematic diagram showing the structure of an optical disc according to an embodiment of the present invention. It is a figure which shows the format of the information recorded with a barcode in the said optical disk. It is a figure which shows the format of disk classification disk classification additional information. It is a figure which shows an example of disk classification additional disk classification information. It is a figure which shows an example of disk classification additional disk classification information. It is a figure which shows the structure of an optical disk recording / reproducing apparatus. It is a figure which shows the operation | movement flow of an optical disk recording / reproducing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Optical disk, a1 ... Clamp area | region, a2 ... Barcode area | region, a3 ... Information recording area | region, 11 ... Servo circuit, 12 ... Control part (reading means, control means), DESCRIPTION OF SYMBOLS 13 ... Spindle motor, 14 ... Optical pick-up (reading means), 17 ... Memory | storage part (control means).

Claims (3)

Disc type information indicating the type of the optical disc is recorded,
The disc type information includes at least one of an identifier that can uniquely identify the type of the optical disc, information that represents the structure of the optical disc, and information that represents the wavelength of light used for reproduction or recording on the optical disc. An optical disc comprising:   2. The optical disc according to claim 1, wherein the disc type information is recorded in an area where information is first read out by an optical disc recording / reproducing apparatus for recording or reproducing the optical disc. Reading means for reading information from a predetermined area of the optical disc;
When the read information is disc type information representing the type of the optical disc, an optical disc recording / reproducing apparatus comprising control means for controlling recording processing or reproducing processing on the optical disc based on the disc type information.

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