JPH09161250A - Information recording medium, information recording and reproducing method thereof - Google Patents

Information recording medium, information recording and reproducing method thereof

Info

Publication number
JPH09161250A
JPH09161250A JP32167395A JP32167395A JPH09161250A JP H09161250 A JPH09161250 A JP H09161250A JP 32167395 A JP32167395 A JP 32167395A JP 32167395 A JP32167395 A JP 32167395A JP H09161250 A JPH09161250 A JP H09161250A
Authority
JP
Japan
Prior art keywords
information recording
recording medium
track
servo
head
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.)
Pending
Application number
JP32167395A
Other languages
Japanese (ja)
Inventor
Yoshiyuki Ikeda
祥行 池田
Yuzo Seo
雄三 瀬尾
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Chemical Corp
Original Assignee
Mitsubishi Chemical Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mitsubishi Chemical Corp filed Critical Mitsubishi Chemical Corp
Priority to JP32167395A priority Critical patent/JPH09161250A/en
Publication of JPH09161250A publication Critical patent/JPH09161250A/en
Pending legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To increase recording capacity by providing plural information recording tracks extending in parallel with the traveling direction of an information recording medium and composed of plural sectors and plural position control signal parts on an information surface. SOLUTION: The track of a long-length information recording medium is composed of plural data sectors and an area as an end of the sector is provided between the data sectors. A position control signal is provided in the partitioned area and has a pattern in which at least two servos b2, b3,... whose running directions and positions are different are provided for one data track. In the figure, a reference signal b1 indicates the end of a sector and the start of a servo signal. As for a concrete method of head position control, the outputs of the servo signals b2, b3 are read out and the head position is controlled so that the amplitudes of signals b2, b3 are made equal. Since the decrease of data recording areas by the servo area is small by using the long-length information recording medium, recording capacity is increased.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【発明の属する技術分野】本発明は、長尺状情報記録媒
体及びその情報記録/再生方法に関し、特に、情報記録
トラックのトラックピッチを縮小可能とし、その情報記
録密度を向上させた長尺状情報記録媒体、及び、そのた
めの情報記録/再生方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a long information recording medium and an information recording / reproducing method thereof, and more particularly to a long information recording medium capable of reducing the track pitch and improving the information recording density. The present invention relates to an information recording medium and an information recording / reproducing method therefor.

【0002】[0002]

【従来の技術】コンピュータシステムでは、ハードディ
スク等の記憶装置に格納された情報のバックアップ、或
いは、他のコンピュータへ移送するため等の目的で、該
情報を磁気テープ等の長尺状情報記録媒体に格納する操
作が一般的に行われている。このような目的で使用され
る記録装置としては、テープストリーマがその代表的な
ものとして挙げられる。ストリーマには、例えば、テー
プの走行方向と平行に多数の情報記録トラックが設けら
れた1/4インチの磁気テープカートリッジが記録媒体
として用いられる。そして、この記録媒体に対向配置さ
れる磁気ヘッドを走行方向と直交する方向に移動させる
ことにより、磁気ヘッドを所定のトラック上に位置させ
て情報の記録/再生を行う。
2. Description of the Related Art In a computer system, information is stored in a long-sized information recording medium such as a magnetic tape for the purpose of backing up information stored in a storage device such as a hard disk or transferring it to another computer. The operation of storing is generally performed. A tape streamer is a typical recording device used for such a purpose. For the streamer, for example, a 1/4 inch magnetic tape cartridge provided with a number of information recording tracks parallel to the running direction of the tape is used as a recording medium. Then, by moving the magnetic head arranged facing the recording medium in a direction orthogonal to the traveling direction, the magnetic head is positioned on a predetermined track to record / reproduce information.

【0003】近年、情報量の増大と情報記録媒体の小型
軽量化のため、ストリーマについても、線記録密度及び
トラック密度の向上に対する要請が強くなっている。し
かし、従来のストリーマではヘッドの移動をステップモ
ータを用いたオープンループ制御で行っており、テープ
の蛇行などに起因するトラックとヘッド位置の誤差を補
正する手段がない。このため、トラックピッチを小さく
してトラック密度を上げることは困難だった。
In recent years, in order to increase the amount of information and reduce the size and weight of the information recording medium, there has been a strong demand for streamers to improve the linear recording density and track density. However, in the conventional streamer, the movement of the head is performed by the open loop control using the step motor, and there is no means for correcting the error between the track and the head position due to the meandering of the tape. Therefore, it is difficult to reduce the track pitch and increase the track density.

【0004】そのため、ヘッド位置とトラック中心との
ずれを検出し、ヘッド位置を常に適正範囲に保つヘッド
位置制御技術が提案されてきている。この技術としては
例えば、記録媒体側の予め定めたトラック(サーボトラ
ック)を位置制御信号の記録用に割り当てるとともに、
磁気ヘッドに複数のヘッドギャップを設け、この複数の
ヘッドギャップのうち何れかが常にサーボトラックを読
み取るように構成し、サーボトラックの再生信号をもと
に正しいヘッド位置とのずれを検出してヘッド位置を制
御する方法がある。
Therefore, there has been proposed a head position control technique for detecting the deviation between the head position and the track center and always keeping the head position within an appropriate range. As this technique, for example, a predetermined track (servo track) on the recording medium side is assigned for recording a position control signal, and
The magnetic head is provided with a plurality of head gaps, and one of the plurality of head gaps is configured to always read the servo track. The head is detected by detecting a deviation from a correct head position based on a reproduction signal of the servo track. There is a way to control the position.

【0005】この方法の適用例を図5を用いて説明す
る。図5は、222のトラックを有する記録媒体におい
て、36〜47トラック、120〜131トラック、2
04〜215トラックをサーボトラックとして割り当
て、3つのヘッドギャップを有するヘッドを用いた時
の、ヘッドギャップの位置を示す図である。
An application example of this method will be described with reference to FIG. FIG. 5 shows 36 to 47 tracks, 120 to 131 tracks, and 2 in a recording medium having 222 tracks.
It is a diagram showing the position of the head gap when tracks 04 to 215 are assigned as servo tracks and a head having three head gaps is used.

【0006】トラック0に対しての記録・再生はヘッド
位置10で第3リードライトギャップ3が行なう。この
際、第1リードライトギャップ1はサーボトラックであ
るトラック36に記録されたサーボ信号を再生する。同
様に第3リードギャップ3がトラック12〜23に対し
て記録・再生する場合は第2リードライトギャップ2
が、第2リードライトギャップ2がトラック60〜71
に対して記録・再生する場合は第3リードライトギャッ
プ3がそれぞれサーボトラック36〜47に対応する。
このようにして、常に何れかのリードライトギャップが
サーボトラックに対応するように配置し、サーボトラッ
クの再生信号からヘッド位置のずれを検知、位置制御す
る。
Recording / reproduction with respect to track 0 is performed by the third read / write gap 3 at the head position 10. At this time, the first read / write gap 1 reproduces the servo signal recorded on the track 36 which is a servo track. Similarly, when the third read gap 3 records / reproduces on / from the tracks 12 to 23, the second read / write gap 2
However, the second read / write gap 2 has tracks 60 to 71.
On the other hand, when recording / reproducing, the third read / write gap 3 corresponds to the servo tracks 36 to 47, respectively.
In this way, one of the read / write gaps is always arranged so as to correspond to the servo track, and the deviation of the head position is detected from the reproduction signal of the servo track and the position is controlled.

【発明が解決しようとする課題】[Problems to be solved by the invention]

【0007】このようなヘッド位置決め機構では、各ト
ラックへの磁気ヘッドの位置決めのために、磁気ヘッド
は、複数のリードライトギャップを持たざるを得なかっ
た。しかもそのギャップ各々の位置関係は直接位置制御
の精度を左右するため、高精度な位置決めのためには高
精度な配置が必要となり、磁気ヘッドが非常に高価とな
る。
In such a head positioning mechanism, the magnetic head had to have a plurality of read / write gaps in order to position the magnetic head on each track. Moreover, since the positional relationship of the gaps directly affects the accuracy of the position control, highly accurate positioning is required for highly accurate positioning, and the magnetic head becomes very expensive.

【0008】さらに、複数トラック覆う領域全てにうま
くヘッドコンタクトさせるのは、非常に難かしく、高度
なヘッド取り付け技術を要する。また、図5に示したよ
うなサーボパターンでは、複数のトラックが全体に渡っ
てサーボ領域として占有されてしまうため、磁気テープ
の有効面積中に占めるサーボ領域として使われる面積が
大きく、サーボ領域による記録容量の制限が大きくなる
傾向があり、これからの高容量化に対し、1つの障害と
なっていた。
Further, it is very difficult to make good head contact with all the areas covering a plurality of tracks, and a high level head mounting technique is required. Further, in the servo pattern as shown in FIG. 5, since a plurality of tracks are occupied as a servo area over the whole area, the area used as a servo area in the effective area of the magnetic tape is large, and the servo area depends on the servo area. There is a tendency that the limitation of the recording capacity becomes large, which is one obstacle to the future increase in the capacity.

【0009】本発明は、上記に鑑み、データ領域の占有
が少なく、かつ高精度なヘッド位置制御が可能な情報記
録媒体およびこの情報記録媒体を利用した情報記録/再
生方法を提供することを目的とする。
In view of the above, it is an object of the present invention to provide an information recording medium that occupies a small data area and is capable of highly accurate head position control, and an information recording / reproducing method using this information recording medium. And

【0010】[0010]

【課題を解決するための手段】本発明の長尺状情報記録
媒体は、情報記録媒体の走行方向と平行に延び、情報が
記録/再生される複数のセクターからなる複数の情報記
録トラックと、該各セクターに夫々対応して配設され、
所定の信号が記録された複数の位置制御信号部とを情報
記録面に備えた長尺状情報記録媒体である。
A long information recording medium of the present invention comprises a plurality of information recording tracks extending in a direction parallel to the traveling direction of the information recording medium and comprising a plurality of sectors for recording / reproducing information. It is arranged corresponding to each of the sectors,
It is an elongated information recording medium having a plurality of position control signal portions in which predetermined signals are recorded on an information recording surface.

【0011】ここで、本明細書で使用する用語「記録/
再生」には、一般的に、記録及び再生の他に、記録又は
再生が含まれる。なお、用語「記録/再生ヘッド」に
は、記録及び再生兼用ヘッド及び再生専用ヘッドが含ま
れる。
Here, the term “record / record” used in this specification.
"Playback" generally includes recording or playback as well as recording and playback. The term “recording / reproducing head” includes a recording / reproducing head and a reproducing-only head.

【0012】又、本発明の長尺状情報記録媒体の記録/
再生方法は特に磁気記録方式に限定されるものではな
い。本発明での情報記録/再生方法は、上記長尺状情報
記録媒体のための情報記録/再生方法であって、隣接す
る2つの位置制御用信号を再生して得られた各再生信号
の強度を相互に比較し、該比較に基づいて情報記録トラ
ック中心からの記録/再生ヘッドの位置の偏差を検出
し、該偏差に基づいて記録/再生ヘッドの位置制御を行
うことを特徴とする。
Recording / recording of the long information recording medium of the present invention
The reproducing method is not particularly limited to the magnetic recording method. An information recording / reproducing method according to the present invention is an information recording / reproducing method for the above long information recording medium, wherein the intensity of each reproduced signal obtained by reproducing two adjacent position control signals. Are compared with each other, the deviation of the position of the recording / reproducing head from the center of the information recording track is detected based on the comparison, and the position control of the recording / reproducing head is performed based on the deviation.

【0013】[0013]

【実施例】次に、図面を参照して本発明を詳細に説明す
る。図1は、本発明による長尺状情報記録媒体の一例を
示す部分構成図である。本発明における長尺状情報記録
媒体はトラックが複数のデータセクタから構成され、デ
ータセクタ間にはセクタの区切りとしての領域が設けら
れている。
Next, the present invention will be described in detail with reference to the drawings. FIG. 1 is a partial block diagram showing an example of a long information recording medium according to the present invention. In the long information recording medium of the present invention, a track is composed of a plurality of data sectors, and an area as a sector delimiter is provided between the data sectors.

【0014】位置制御用信号(サーボ信号)は、この区
切り領域に設けられ、図1に示すように走行方向位置の
異なる複数のサーボ(b2、b3...)を1つのデータ
トラックに対して最低2つ設けたパターンを有してい
る。そして、トラッキングエラーが生じた際に正しいト
ラックへとヘッド位置を修正するためのアルゴリズムが
簡単になるため、在る周期で配置をくりかえすのが効率
的である。
A position control signal (servo signal) is provided in this delimiter area, and as shown in FIG. 1, a plurality of servos (b2, b3 ...) Having different traveling direction positions are provided for one data track. At least two patterns are provided. Then, since the algorithm for correcting the head position to the correct track when a tracking error occurs becomes simple, it is efficient to repeat the arrangement at an existing cycle.

【0015】しかし、サーボパターンはこのようなくり
かえしパターンに限られず、隣接する2つのサーボの走
行方向位置が異っており、トラッキングエラー発生時の
位置修正アルゴリズムに沿って配置されていればよい。
また、各情報記録トラックに対応するサーボ部の走行方
向と直交する方向の中心は、情報記録トラックの中心線
上にはなく、これから1/2トラックピッチだけずれた
位置に配置するのが好ましい。
However, the servo pattern is not limited to such a repetitive pattern, and it is sufficient that two adjacent servos have different positions in the traveling direction and are arranged in accordance with a position correction algorithm when a tracking error occurs.
Further, it is preferable that the center of the servo section corresponding to each information recording track in the direction orthogonal to the traveling direction is not on the center line of the information recording track but is displaced from the center line by 1/2 track pitch.

【0016】図において、基準信号b1はセクタの終わ
りを示すとともに、サーボ信号の開始を示す。また、こ
の基準信号b1が検出されてからサーボ信号が検出され
るまでの時間を用いてトラック番号を検知することも可
能である。
In the figure, the reference signal b1 indicates the end of the sector and the start of the servo signal. Further, it is possible to detect the track number by using the time from the detection of the reference signal b1 to the detection of the servo signal.

【0017】上記構成に基づいて、或る1つの情報記録
トラック上を走行する記録/再生ヘッドは、当該トラッ
クに隣接する2つのサーボ部の信号を連続的に再生す
る。この場合、記録/再生ヘッドの位置の情報記録トラ
ック中心線からの偏差に応じて、これら2つのサーボ信
号は振幅が相互に異なる信号として再生される。
Based on the above structure, the recording / reproducing head running on a certain information recording track continuously reproduces the signals of the two servo sections adjacent to the track. In this case, these two servo signals are reproduced as signals having different amplitudes depending on the deviation of the position of the recording / reproducing head from the center line of the information recording track.

【0018】すなわち、ヘッド位置がトラック中心b4
とずれていない場合、サーボ信号の再生波形は模式的に
図3のように示され、b2、b3の再生波形の振幅は等
しい。しかし、ヘッド位置が上方にずれるとb2の再生
波形の振幅は大きくなり、b3の再生波形の振幅は小さ
くなるため、図4の様な波形となる。一方、逆に下方に
ずれると、図5のような波形が得られる。
That is, the head position is the track center b4.
When there is no deviation, the reproduced waveform of the servo signal is schematically shown in FIG. 3, and the reproduced waveforms b2 and b3 have the same amplitude. However, when the head position shifts upward, the amplitude of the reproduced waveform of b2 increases and the amplitude of the reproduced waveform of b3 decreases, resulting in the waveform as shown in FIG. On the other hand, when it shifts downward, the waveform as shown in FIG. 5 is obtained.

【0019】具体的なヘッド位置制御の方法としては、
サーボパターン中のサーボ信号(b2,b3)の出力を
読み込み、b2,b3の信号振幅の大きさを求め、b
2,b3のそれぞれの信号振幅の大きさの差より、ヘッ
ドのオフトラック量が、b2,b3の大小関係より、ヘ
ッドのオフトラック方向が求められ、b2,b3の信号
振幅量が等しくなるようにヘッド位置を制御すればよ
い。このヘッド制御動作が、各サーボ領域で次々に繰り
返しおこなわれることで、ヘッドが所望の位置に保たれ
る。このような制御は信号処理用のマイクロコンピュー
タ(DSP)と比較器との組み合わせで実現できる。
A specific head position control method is as follows.
The output of the servo signals (b2, b3) in the servo pattern is read, the magnitude of the signal amplitude of b2, b3 is calculated, and b
The off-track amount of the head is obtained from the difference between the signal amplitudes of b2 and b3, and the off-track direction of the head is obtained from the magnitude relationship of b2 and b3 so that the signal amplitudes of b2 and b3 are equal. The head position may be controlled to. By repeating this head control operation in each servo area one after another, the head is maintained at a desired position. Such control can be realized by a combination of a signal processing microcomputer (DSP) and a comparator.

【0020】1/4インチ幅の磁気記録テープに、トラ
ックピッチ12μmでトラックを設け、テープを90イ
ンチ/秒で走行させた場合にサーボ信号開始点が90μ
s毎に再生されるように、図1示のように4トラック周
期でサーボ信号を書き込んだ。として記録密度を700
00ビット/インチ、テープの蛇行量は実測値で15μ
mで、トラックピッチよりも大きかったが、問題なくデ
ータの記録・再生ができた。
When a track is provided at a track pitch of 12 μm on a 1/4 inch wide magnetic recording tape and the tape is run at 90 inch / sec, the servo signal start point is 90 μm.
As shown in FIG. 1, the servo signal was written in a 4-track cycle so that the servo signal was reproduced every s. Recording density is 700
00 bits / inch, tape meandering amount is 15μ
In m, it was larger than the track pitch, but data could be recorded and reproduced without problems.

【0021】[0021]

【発明の効果】以上説明したように、本発明による長尺
状情報記録媒体を用いることにより、ヘッドに設けるリ
ードライトギャップが1つで済むため、ヘッドの単価が
安価で、かつ設計調整も簡単となる。また、複数のトラ
ック全体をサーボ領域として割り当てる方法に比べ、サ
ーボ領域によるデータ記録領域の減少が少ないので記録
容量の増大が可能となる。
As described above, by using the long information recording medium according to the present invention, only one read / write gap needs to be provided in the head, so that the unit price of the head is low and the design adjustment is easy. Becomes Further, as compared with the method of allocating the whole of a plurality of tracks as the servo area, the data recording area is less reduced by the servo area, so that the recording capacity can be increased.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明による長尺状情報記録媒体の一部構成を
示す図
FIG. 1 is a diagram showing a partial configuration of a long information recording medium according to the present invention.

【図2】ヘッド位置が正常な場合のサーボ信号再生波形
を示す図
FIG. 2 is a diagram showing a servo signal reproduction waveform when the head position is normal.

【図3】ヘッド位置が上方にずれた場合のサーボ信号再
生波形を示す図
FIG. 3 is a diagram showing a servo signal reproduction waveform when the head position is displaced upward.

【図4】ヘッド位置が下方にずれた場合のサーボ信号再
生波形を示す図
FIG. 4 is a diagram showing a servo signal reproduction waveform when the head position is displaced downward.

【図5】従来のヘッド位置制御方法を説明する図FIG. 5 is a diagram illustrating a conventional head position control method.

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 長尺状情報記録媒体であって、該情報記
録媒体の走行方向と平行に延び、情報が記録/再生され
る複数のセクターからなる、複数の情報記録トラック
と、該各セクターに夫々対応して配設され、所定の信号
が記録された複数の位置制御信号部を情報記録面に備え
た長尺状情報記録媒体。
1. A long information recording medium, comprising: a plurality of information recording tracks, each sector extending in a direction parallel to the running direction of the information recording medium and having information recorded / reproduced thereon; And a long information recording medium having a plurality of position control signal portions each having a predetermined signal recorded on the information recording surface.
【請求項2】 請求項1に記載の長尺状情報記録媒体の
ための情報記録/再生方法であって、隣接する2つの位
置制御信号部の再生信号強度を比較し、該比較に基づい
て情報記録トラック中心からの記録/再生ヘッドの位置
の偏差を検出し、該偏差に基づいて記録/再生ヘッドの
位置制御を行うことを特徴とする情報記録/再生方法。
2. An information recording / reproducing method for a long information recording medium according to claim 1, wherein the reproducing signal intensities of two adjacent position control signal portions are compared, and based on the comparison. An information recording / reproducing method characterized in that a deviation of the position of the recording / reproducing head from the center of the information recording track is detected and the position of the recording / reproducing head is controlled based on the deviation.
JP32167395A 1995-12-11 1995-12-11 Information recording medium, information recording and reproducing method thereof Pending JPH09161250A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP32167395A JPH09161250A (en) 1995-12-11 1995-12-11 Information recording medium, information recording and reproducing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP32167395A JPH09161250A (en) 1995-12-11 1995-12-11 Information recording medium, information recording and reproducing method thereof

Publications (1)

Publication Number Publication Date
JPH09161250A true JPH09161250A (en) 1997-06-20

Family

ID=18135144

Family Applications (1)

Application Number Title Priority Date Filing Date
JP32167395A Pending JPH09161250A (en) 1995-12-11 1995-12-11 Information recording medium, information recording and reproducing method thereof

Country Status (1)

Country Link
JP (1) JPH09161250A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7428117B2 (en) 2004-09-21 2008-09-23 Fujifilm Corporation Servo signal inspecting device and method for inspecting servo signal
JP2009110621A (en) * 2007-10-31 2009-05-21 Hitachi Maxell Ltd Magnetic tape
JP2009151851A (en) * 2007-12-19 2009-07-09 Sony Corp Magnetic tape, magnetic tape apparatus, servo pattern recording apparatus, magnetic tape producing method, and recording method
JP2010182411A (en) * 2010-03-26 2010-08-19 Sony Corp Magnetic tape and servo pattern recording apparatus

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7428117B2 (en) 2004-09-21 2008-09-23 Fujifilm Corporation Servo signal inspecting device and method for inspecting servo signal
JP2009110621A (en) * 2007-10-31 2009-05-21 Hitachi Maxell Ltd Magnetic tape
JP2009151851A (en) * 2007-12-19 2009-07-09 Sony Corp Magnetic tape, magnetic tape apparatus, servo pattern recording apparatus, magnetic tape producing method, and recording method
US8089716B2 (en) 2007-12-19 2012-01-03 Sony Corporation Magnetic tape, magnetic tape apparatus, servo pattern recording apparatus, magnetic tape producing method, and magnetic tape recording method
JP2010182411A (en) * 2010-03-26 2010-08-19 Sony Corp Magnetic tape and servo pattern recording apparatus

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