JPH0355890B2 - - Google Patents
Info
- Publication number
- JPH0355890B2 JPH0355890B2 JP24366584A JP24366584A JPH0355890B2 JP H0355890 B2 JPH0355890 B2 JP H0355890B2 JP 24366584 A JP24366584 A JP 24366584A JP 24366584 A JP24366584 A JP 24366584A JP H0355890 B2 JPH0355890 B2 JP H0355890B2
- Authority
- JP
- Japan
- Prior art keywords
- address
- sector
- signal
- section
- reproducing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000003287 optical effect Effects 0.000 claims abstract description 25
- 230000035945 sensitivity Effects 0.000 abstract description 7
- 238000000034 method Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000007689 inspection Methods 0.000 description 5
- 238000001514 detection method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 238000000151 deposition Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/18—Error detection or correction; Testing, e.g. of drop-outs
- G11B20/1883—Methods for assignment of alternate areas for defective areas
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
- G11B19/02—Control of operating function, e.g. switching from recording to reproducing
- G11B19/04—Arrangements for preventing, inhibiting, or warning against double recording on the same blank or against other recording or reproducing malfunctions
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/12—Formatting, e.g. arrangement of data block or words on the record carriers
- G11B20/1217—Formatting, e.g. arrangement of data block or words on the record carriers on discs
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
- G11B27/10—Indexing; Addressing; Timing or synchronising; Measuring tape travel
- G11B27/19—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier
- G11B27/28—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier by using information signals recorded by the same method as the main recording
- G11B27/30—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier by using information signals recorded by the same method as the main recording on the same track as the main recording
- G11B27/3027—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information detectable on the record carrier by using information signals recorded by the same method as the main recording on the same track as the main recording used signal is digitally coded
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/004—Recording, reproducing or erasing methods; Read, write or erase circuits therefor
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/007—Arrangement of the information on the record carrier, e.g. form of tracks, actual track shape, e.g. wobbled, or cross-section, e.g. v-shaped; Sequential information structures, e.g. sectoring or header formats within a track
- G11B7/00745—Sectoring or header formats within a track
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B2020/1087—Digital recording or reproducing wherein a selection is made among at least two alternative ways of processing
- G11B2020/10879—Digital recording or reproducing wherein a selection is made among at least two alternative ways of processing the kind of record carrier being the selection criterion
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B2220/00—Record carriers by type
- G11B2220/20—Disc-shaped record carriers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B2220/00—Record carriers by type
- G11B2220/20—Disc-shaped record carriers
- G11B2220/21—Disc-shaped record carriers characterised in that the disc is of read-only, rewritable, or recordable type
- G11B2220/215—Recordable discs
- G11B2220/218—Write-once discs
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B2220/00—Record carriers by type
- G11B2220/20—Disc-shaped record carriers
- G11B2220/25—Disc-shaped record carriers characterised in that the disc is based on a specific recording technology
- G11B2220/2537—Optical discs
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Signal Processing For Digital Recording And Reproducing (AREA)
- Optical Recording Or Reproduction (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は複数に分割されたセクタ構造を有する
光デイスクに関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical disk having a sector structure divided into a plurality of sectors.
従来の技術
スパイラル状又は同心円状の案内溝が刻まれた
基板上に光記録材料を蒸着し形成した情報記録領
域を有し、この情報記録領域が複数に分割された
セクタ構造を有する光デイスクにセクタ単位で情
報の記録再生を行なう光デイスク記録再生装置で
は、情報を正規のセクタに記録し、正規のセクタ
から再生できなくてはならない。そして、記録さ
れた情報は必ず再生できなくてはならない。そこ
で、従来の光デイスク記録再生装置においては、
セクタの先頭にアドレス部を設ける方式、セクタ
間に入つているセクタ分離信号を計数し、セクタ
のアドレスを得る方式、或いは、特願昭58−
230104に示す様に、再生時に最適レベルでアドレ
ス検出を行ない、記録時には検出感度を下げてア
ドレス検出を行なうという方式が採られ、光デイ
スク記録再生装置により、アドレス部の信頼性を
確保されていた。2. Description of the Related Art An optical disk has an information recording area formed by vapor-depositing an optical recording material on a substrate with spiral or concentric guide grooves, and has a sector structure in which this information recording area is divided into a plurality of parts. In an optical disk recording and reproducing apparatus that records and reproduces information on a sector-by-sector basis, it is necessary to be able to record information in and reproduce information from regular sectors. Furthermore, recorded information must be able to be reproduced. Therefore, in conventional optical disk recording and reproducing devices,
A method of providing an address section at the beginning of a sector, a method of counting sector separation signals between sectors and obtaining the sector address, or a method of obtaining a sector address by applying
As shown in 230104, a method was adopted in which address detection was performed at an optimal level during playback, and address detection was performed with lower detection sensitivity during recording, and the reliability of the address section was ensured by an optical disk recording/playback device. .
発明が解決しようとする問題点
しかしながら、一般にセクタのアドレスを発生
する信号は時間的に短く、有効な誤り制御を施す
ことができず、また、光デイスク記録再生装置が
異なる場合や、記録時のフオーカスやトラツキン
グサーボの状態により、アドレス部の信頼性が常
に保証されるわけではないという問題点を有して
いた。Problems to be Solved by the Invention However, the signals that generate sector addresses are generally short in time and cannot be subject to effective error control. There is a problem in that the reliability of the address section cannot always be guaranteed depending on the state of the focus and tracking servos.
本発明がかかる点に鑑み、アドレス部が十分な
信頼性を保証された光デイスクを提供することを
目的とする。 In view of this point, it is an object of the present invention to provide an optical disc in which the address section is guaranteed to have sufficient reliability.
問題点を解決するための手段
本発明は、情報記録領域が複数に分割されたセ
クタ構造を有しかつ前記各セクタには予めアドレ
ス信号が記録されているアドレス部およびデータ
を記録するためのデータ記録部を有し、かつ前記
アドレス部を再生した時の再生アドレス信号より
アドレスを再生する際の２値化のレベルを変更し
再生感度を下げて再生アドレス信号からアドレス
を再生し、この再生されたアドレスと該当セクタ
のセクタアドレスとを比較し、一致しないとき当
該アドレス部に所定の信号を重ね書きし、以後の
再生に対してこのアドレス部が再生不能となる処
置を施した光デイスクである。Means for Solving the Problems The present invention provides an information recording area that has a sector structure divided into a plurality of sectors, and each sector has an address section in which an address signal is recorded in advance, and a data section for recording data. It has a recording section, and changes the binarization level when reproducing the address from the reproduced address signal when the address section is reproduced, lowers the reproduction sensitivity, reproduces the address from the reproduced address signal, and reproduces the address from the reproduced address signal. This is an optical disc that compares the address of the specified sector with the sector address of the corresponding sector, and if they do not match, overwrites the address section with a predetermined signal, making this address section unreproducible for subsequent playback. .
作 用
本発明は前記した構成により、再生時の状態に
よりアドレス検出の成否が左右される信頼性に欠
けるアドレス部を完全に再生不能にすることによ
り、当該セクタには情報を記録することができな
いようにし、十分な信頼性が保証されるアドレス
部のみが存在する光デイスクとしている。Effect: With the above-described configuration, the present invention completely disables reproduction of the unreliable address section in which the success or failure of address detection depends on the state at the time of reproduction, thereby making it impossible to record information in the sector. In this way, the optical disk is made up of only an address section that guarantees sufficient reliability.
実施例
第１図は本発明の一実施例における光デイスク
の記録フオーマツトを示した図である。Embodiment FIG. 1 is a diagram showing a recording format of an optical disk in an embodiment of the present invention.
第１図において、１はアドレス部、５はデータ
記録部、２はアドレスマーク、３はアドレスデー
タ部、４はCRC部である。各セクタはアドレス
部１およびデータ記録部５により構成され、アド
レス部１は、アドレス部の始まりを示すアドレス
マーク２、アドレスデータ部３、そのチエツクで
あるCRC部４からなり、第ｎセクタのセクタア
ドレスをｎとすると、第ｎセクタのアドレス部に
は記録再生を行なう前にあらかじめ初期フオーマ
ツテイング等によりセクタアドレスｎが記録され
ている。 In FIG. 1, 1 is an address section, 5 is a data recording section, 2 is an address mark, 3 is an address data section, and 4 is a CRC section. Each sector is composed of an address section 1 and a data recording section 5, and the address section 1 consists of an address mark 2 indicating the start of the address section, an address data section 3, and a CRC section 4 that is a check for the address mark 2, and a CRC section 4 that is a check for the address mark 2. Assuming that the address is n, the sector address n is recorded in advance in the address portion of the n-th sector by initial formatting or the like before recording/reproducing.
第２図は第１図に示したような記録フオーマツ
トを有する光デイスクを検査する装置の実施例の
ブロツク図である。 FIG. 2 is a block diagram of an embodiment of an apparatus for inspecting an optical disk having a recording format as shown in FIG.
第２図において、６は制御部、７はコンパレー
タ、８はアドレスデコーダ、９は信号発生器、１
０は記録再生部、１１は光学式ピツクアツプ、１
２は光デイスクである。制御部６はCPU等で構
成されている。 In FIG. 2, 6 is a control unit, 7 is a comparator, 8 is an address decoder, 9 is a signal generator, 1
0 is a recording/reproducing section, 11 is an optical pickup, 1
2 is an optical disk. The control unit 6 is composed of a CPU and the like.
いま、あるセクタを検査する時、制御部６はそ
のセクタアドレス１３を記録再生部１０とアドレ
スデコーダ８に送る。記録再生部１０は光学式ピ
ツクアツプ１１を制御し、セクタのアドレス部１
を順次読み込み、セクタアドレス１３に該当する
セクタを検索する。コンパレータ７は、記録再生
部１０より送られる再生アドレス信号１７を最適
値に設定されたレベル信号１８により二値化し、
アドレス信号１４を作る。アドレスデコーダ８
は、アドレス信号１４をデコードし、該当セクタ
を検出した場合、一致信号１５、検出できない場
合、不一致信号１６をそれぞれ制御部６に送る。
該当セクタを検出すると制御部６はレベル信号１
８を変更することにより再生感度を下げて再び該
当セクタを検索する。感度を下げて二値化された
再生アドレス１４はアドレスデコーダ８に送ら
れ、セクタアドレス１３と比較され、一致が検出
された場合、アドレスデコーダ８は一致信号１５
を制御部６に送り、該当セクタのアドレス部１は
十分に信頼性があるとし検査を終える。一方、該
当セクタアドレス１３との一致が検出されない場
合、アドレスデコーダ８は不一致信号１６を制御
部６に送る。制御部６は再びレベル信号１８を最
適値に変更し、該当セクタの一つ前のセクタを検
出し、１セクタ分の時間遅延の後、書込信号１７
を信号発生器９と記録再生部１０に送る。信号発
生器９は所定の記録信号１８を記録再生部１０に
送り、記録再生部１０は該当セクタのアドレス部
１が再生不能となるように重ね書きを行い該当セ
クタの検査を終える。 Now, when inspecting a certain sector, the control section 6 sends the sector address 13 to the recording/reproducing section 10 and the address decoder 8. The recording/reproducing section 10 controls the optical pickup 11 and reads the address section 1 of the sector.
are sequentially read and the sector corresponding to sector address 13 is searched. The comparator 7 binarizes the reproduction address signal 17 sent from the recording/reproduction section 10 using a level signal 18 set to an optimal value.
An address signal 14 is generated. address decoder 8
decodes the address signal 14 and sends a match signal 15 to the control unit 6 if the corresponding sector is detected, and a mismatch signal 16 if the sector cannot be detected.
When the corresponding sector is detected, the control unit 6 outputs a level signal 1.
8, the playback sensitivity is lowered and the corresponding sector is searched again. The playback address 14, which has been binarized with lowered sensitivity, is sent to the address decoder 8 and compared with the sector address 13. If a match is detected, the address decoder 8 outputs a match signal 15.
is sent to the control unit 6, and it is determined that the address part 1 of the corresponding sector is sufficiently reliable, and the inspection is completed. On the other hand, if no match with the corresponding sector address 13 is detected, the address decoder 8 sends a mismatch signal 16 to the control unit 6. The control unit 6 again changes the level signal 18 to the optimum value, detects the sector immediately before the corresponding sector, and after a time delay of one sector, writes the write signal 17.
is sent to the signal generator 9 and the recording/reproducing section 10. The signal generator 9 sends a predetermined recording signal 18 to the recording/reproducing section 10, and the recording/reproducing section 10 overwrites the address part 1 of the sector so that it becomes unreproducible, and finishes the inspection of the sector.
セクタのアドレス部１が再生不能となるように
重ね書きを行う例として、以下の方法がある。 As an example of overwriting so that the address part 1 of the sector becomes unreproducible, there is the following method.
(1) アドレス部１全体に重ね書きをする。（第１
図ａ）。(1) Overwrite the entire address section 1. (1st
Diagram a).
(2) アドレスマーク２に重ね書きをする（第１図
ｂ）。(2) Overwrite address mark 2 (Figure 1b).
(3) CRCエラーが発生するように、CRC部３の
長さ以下の誤りを起こすよう重ね書きをする
（第１図ｃ）。(3) Overwrite to cause an error less than the length of the CRC section 3 so that a CRC error occurs (Fig. 1c).
また、重ね書きをする記号は、DC信号、あるい
はその他のこのセクタのアドレスが読めない条件
を満足する任意の信号であつて良い。なおこの
他、重ね書きのやり方としては、種々の方法が可
能である。Further, the overwritten symbol may be a DC signal or any other signal that satisfies the condition that the address of this sector cannot be read. In addition to this, various methods are possible for overwriting.
本実施例によれば、光デイスク検査装置により
すべてのセクタのアドレス部１の検査を行えば、
安定なアドレス部のみを有する光デイスクを提供
することができる。 According to this embodiment, if the address part 1 of all sectors is inspected by the optical disk inspection device,
It is possible to provide an optical disc having only a stable address area.
なお、本発明は上記し且つ図示した実施例のみ
に限定されることなく、この発明の要旨を逸脱し
ない範囲で種々の変形や適用が可能であることは
言う迄もない。 It goes without saying that the present invention is not limited to the embodiments described above and illustrated, and that various modifications and applications can be made without departing from the gist of the invention.
発明の効果
以上説明したように、本発明は、検査時、２値
化のレベルを変更することにより再生感度を下げ
てアドレス部を再生し、アドレス部が不安定なセ
クタを検出しこのセクタのアドレス部を再生不能
にしたアドレス部が安定なセクタのみを有する光
デイスクであり、記録再生を行う光デイスク記録
再生装置が異なる場合や記録時のフオーカスやト
ラツキングサーボの状態によりアドレス部の信頼
性が左右されることなく、光デイスク記録再生装
置に対する互換性に富み、安定した情報の記録再
生を行うことが可能となる。Effects of the Invention As explained above, the present invention reproduces the address part by lowering the reproduction sensitivity by changing the level of binarization during inspection, detects a sector in which the address part is unstable, and detects a sector in which the address part is unstable. This is an optical disc that has only stable sectors in which the address part is made unplayable, and the reliability of the address part may vary depending on the optical disc recording/playback device that performs recording and playback or the state of the focus and tracking servo during recording. It is highly compatible with optical disk recording and reproducing devices, and it is possible to perform stable information recording and reproducing without being affected by this.
第１図は本発明の一実施例における光デイスク
の記録フオーマツトの一例を示した図、第２図は
同実施例の光デイスクの検査装置の一実施例を示
すブロツク図である。
１……アドレス部、２……アドレスマーク、３
……アドレスデータ部、４……CRC部、５……
データ記録部、６……制御部、７……コンパレー
タ、８……アドレスデコーダ、９……信号発生
器、１０……記録再生部、１２……光デイスク。
FIG. 1 is a diagram showing an example of a recording format of an optical disk according to an embodiment of the present invention, and FIG. 2 is a block diagram showing an embodiment of an optical disk inspection apparatus according to the same embodiment. 1...Address section, 2...Address mark, 3
...Address data section, 4...CRC section, 5...
Data recording unit, 6...Control unit, 7...Comparator, 8...Address decoder, 9...Signal generator, 10...Recording/reproducing unit, 12...Optical disk.
Claims (1)
で前記各セクタには予めアドレス信号が記録され
ているアドレス部およびデータを記録するための
データ記録部を有し、かつ前記アドレス部を再生
した時の再生アドレス信号よりアドレスを再生す
る際の２値化レベルを変更し再生されたアドレス
と該当セクタのセクタアドレスとを比較し、一致
しないときに当該アドレス部に所定の信号が重ね
書きされ以後の再生に対してこのアドレス部が再
生不能となる処置を施した光デイスク。 ２ セクタのアドレス部がアドレスデータ部の始
まりを示すアドレスマークとセクタのアドレスを
示すアドレスデータ部とそのチエツク用信号であ
るCRC部から構成され、かつ、前記セクタアド
レス部あるいはCRC部に前記CRC部の長さ以下
の所定の信号を重ね書きし、以後の再生に対して
CRCエラーが発生するようにして当該アドレス
部が再生不能となる処置を施した特許請求の範囲
第１項記載の光デイスク。[Scope of Claims] 1. The information recording area has a sector structure divided into a plurality of sectors, and each sector has an address section in which an address signal is recorded in advance and a data recording section for recording data, and The binarization level when reproducing the address is changed from the reproduced address signal when the address part is reproduced, the reproduced address and the sector address of the corresponding sector are compared, and if they do not match, a predetermined signal is sent to the address part. An optical disc that has been overwritten so that the address section becomes unplayable for subsequent playback. 2. The address part of the sector is composed of an address mark indicating the start of the address data part, an address data part indicating the address of the sector, and a CRC part which is a check signal for the sector address, and the CRC part is included in the sector address part or the CRC part. Overwrites a predetermined signal that is less than or equal to the length of
2. The optical disc according to claim 1, wherein a CRC error occurs so that the address section becomes unplayable.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24366584A JPS61122931A (en) | 1984-11-19 | 1984-11-19 | Optical disk |
| US06/743,314 US4695993A (en) | 1984-06-15 | 1985-06-10 | Optical information recording and reproducing apparatus and optical disc |
| CA000483650A CA1263476A (en) | 1984-06-15 | 1985-06-11 | Error control of sector address and optical disc |
| DE8585107265T DE3585750D1 (en) | 1984-06-15 | 1985-06-12 | OPTICAL INFORMATION RECORDING AND PLAYBACK DEVICE AND OPTICAL DISK. |
| EP85107265A EP0164746B1 (en) | 1984-06-15 | 1985-06-12 | Optical information recording and reproducing apparatus and optical disc |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24366584A JPS61122931A (en) | 1984-11-19 | 1984-11-19 | Optical disk |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61122931A JPS61122931A (en) | 1986-06-10 |
| JPH0355890B2 true JPH0355890B2 (en) | 1991-08-26 |
Family
ID=17107177
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24366584A Granted JPS61122931A (en) | 1984-06-15 | 1984-11-19 | Optical disk |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61122931A (en) |
-
1984
- 1984-11-19 JP JP24366584A patent/JPS61122931A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61122931A (en) | 1986-06-10 |
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