JPH0452536B2 - - Google Patents
Info
- Publication number
- JPH0452536B2 JPH0452536B2 JP58228731A JP22873183A JPH0452536B2 JP H0452536 B2 JPH0452536 B2 JP H0452536B2 JP 58228731 A JP58228731 A JP 58228731A JP 22873183 A JP22873183 A JP 22873183A JP H0452536 B2 JPH0452536 B2 JP H0452536B2
- Authority
- JP
- Japan
- Prior art keywords
- track
- signal
- tracking
- width
- light beam
- 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 - Lifetime
Links
- 230000003287 optical effect Effects 0.000 claims description 16
- 239000000463 material Substances 0.000 description 11
- 238000010586 diagram Methods 0.000 description 4
- 230000035939 shock Effects 0.000 description 4
- 238000001514 detection method Methods 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Classifications
-
- 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
- G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
- G11B7/2407—Tracks or pits; Shape, structure or physical properties thereof
- G11B7/24085—Pits
-
- 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
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B7/0938—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following servo format, e.g. guide tracks, pilot signals
Description
【発明の詳細な説明】
産業上の利用分野
本発明は半導体レーザ等の光源を利用して信号
を記録する光学式情報記録担体（以下単に記録担
体と呼ぶ）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 information record carrier (hereinafter simply referred to as record carrier) that records signals using a light source such as a semiconductor laser.
従来例の構成とその問題点
光学式記録生装置に用いる記録担体は、予じめ
基材表面に凹あるいは凸条の形態でトラツクを形
成し、その基材表面に記録材料層を蒸着等の手段
によつて形成したものが使われている。基材表面
上の凹凸の形態のトラツクは、光ビームを追跡さ
せて記録材料層に信号を記録するあるいは記録材
料層に記録されている信号を再生する為の追跡用
トラツク部と、単位トラツクあるいは追跡用トラ
ツクを識別する為に番地あるいはセクター等の信
号を凹凸のビツト列として記録されている凹凸信
号部との組み合せで構成されている。トラツクの
深さd0は、基材の屈析率をn0、光ビームの波長を
λ0とすると光路長n0d0はn0d0＝λ0／８となるよう
に、また追跡用トラツク部の幅と凹凸信号部のビ
ツト幅は同じ幅にされている。トラツク幅は光ビ
ームとトラツクの位置ずれすなわちトラツキング
制御信号が検出でき、かつ凹凸信号部からの信号
が検出できる幅に設定されている。光ビームがト
ラツク上を走査するように制御するトラツキング
制御とトラツク幅の関係は、トラツク幅が広くな
るほど振動あるいは衝撃等の外乱に対してトラツ
ク飛びが生じない強い制御系が構成できる。しか
し従来の記録担体は、トラツク幅が広くなると凹
凸信号部からの再生信号のＳ／Ｎが低下する為
に、トラツク幅は凹凸信号部からの再生信号とト
ラツキング制御信号が共にある程度検出できる幅
に設定されていた。Conventional structure and problems The record carrier used in an optical recorder has tracks formed in the form of concave or convex stripes on the surface of the base material in advance, and a layer of recording material is deposited on the surface of the base material, such as by vapor deposition. Those formed by means are used. The uneven track on the surface of the base material includes a tracking track section for tracking a light beam to record a signal on the recording material layer or reproducing a signal recorded on the recording material layer, and a unit track section or In order to identify a tracking track, a signal such as an address or a sector is combined with a concave-convex signal portion recorded as a concave-convex bit string. The depth d 0 of the track is determined such that, where n 0 is the refractive index of the base material and λ 0 is the wavelength of the light beam, the optical path length n 0 d 0 is n 0 d 0 = λ 0 /8. The width of the track section and the bit width of the uneven signal section are made to be the same width. The track width is set to such a width that a positional deviation between the light beam and the track, that is, a tracking control signal, can be detected, and a signal from the uneven signal portion can be detected. Regarding the relationship between the tracking control for controlling the light beam to scan over the track and the track width, the wider the track width, the stronger a control system can be constructed in which the track does not jump due to disturbances such as vibrations or shocks. However, in conventional record carriers, as the track width becomes wider, the S/N of the reproduced signal from the uneven signal section decreases. It was set.
従つて従来の記録担体を光学式記録再生装置に
装填して記録再生を行なう場合に、装置に外部か
ら振動あるいは衝撃が加わるとトラツク飛びが生
じやすく、また凹凸信号部からの再生信号も安定
に検出できなかつた。 Therefore, when a conventional record carrier is loaded into an optical recording and reproducing device for recording and reproducing, if vibration or shock is applied to the device from the outside, track jumps are likely to occur, and the reproduced signal from the uneven signal section becomes unstable. Could not be detected.
発明の目的
本発明の目的は、前記従来の欠点を除去し、外
部振動あるいは衝撃に対して強い制御系が構成で
き、かつ凹凸信号部からの再生信号も良好に検出
できる記録担体を提供せんとすることである。OBJECTS OF THE INVENTION It is an object of the present invention to provide a record carrier that eliminates the above-mentioned conventional drawbacks, allows a control system to be configured that is strong against external vibrations or shocks, and that also allows good detection of reproduced signals from the uneven signal section. It is to be.
本発明の記録担体は、追跡用トラツク部の幅を
広く、凹凸信号部のビツト幅を狭くして、トラツ
ク飛びが生じにくく、かつ凹凸信号部からの再生
信号も良好に検出できるように構成したものであ
る。 The record carrier of the present invention has a wide tracking track section and a narrow bit width of the uneven signal section, so that track skipping is less likely to occur, and the reproduced signal from the uneven signal section can also be detected satisfactorily. It is something.
実施例の説明
以下図面を参照して本発明を詳細に説明する。
尚、図面の説明に用いる符号において、同一のも
のについては同一符号を用いる。DESCRIPTION OF EMBODIMENTS The present invention will be described in detail below with reference to the drawings.
It should be noted that the same reference numerals are used for the same parts in the description of the drawings.
第１図は本発明の記録媒体の一実施例であり、
記録担体１は中心に取り付け孔２が開けられてい
る。記録担体１のトラツクは同心円状になつてお
り、同じ円状のトラツクが設けられている領域は
追跡用トラツク部の領域３と凹凸信号部の領域４
より構成されている。 FIG. 1 shows an embodiment of the recording medium of the present invention.
The record carrier 1 has a mounting hole 2 formed in its center. The tracks of the record carrier 1 are concentric circles, and the areas where the same circular tracks are provided are area 3 of the tracking track section and area 4 of the uneven signal section.
It is composed of
第１図に破線で示した領域５の拡大断面図を第
２図に示す。 FIG. 2 shows an enlarged cross-sectional view of region 5 indicated by broken lines in FIG.
基材２１の表面には凸条の形態のトラツク２２
が所定のピツチで設けられており、その表面上に
記録材料層２３が設けられている。トラツクが設
けられている領域は追跡用トラツク部の領域３と
凹凸信号部の領域４より構成されており、斜線で
示した追跡用トラツク部２４の溝深さ２５と凹凸
信号部のピツト２６の溝深さ２７は等しく、基材
の屈折率n0，溝深さをd0，光ビームの波長をλ0と
すると、溝深さd0は、λ0／8n0とされている。同
心円状のトラツク２２のトラツク方向は矢印２８
の方向であり、追跡用トラツク部の溝幅２９は凹
凸信号部のピツト２６の溝幅３０より広くされて
いる。尚前述したように信号は斜線で示した追跡
用トラツク部２４上に記録される。 Tracks 22 in the form of protrusions are provided on the surface of the base material 21.
are provided at a predetermined pitch, and a recording material layer 23 is provided on the surface thereof. The area where the track is provided is composed of the area 3 of the tracking track part and the area 4 of the uneven signal part, and the groove depth 25 of the tracking track part 24 and the pit 26 of the uneven signal part are shown by diagonal lines. The groove depths 27 are equal, and when the refractive index of the base material is n 0 , the groove depth is d 0 , and the wavelength of the light beam is λ 0 , the groove depth d 0 is λ 0 /8n 0 . The track direction of the concentric tracks 22 is indicated by the arrow 28.
The groove width 29 of the tracking track portion is wider than the groove width 30 of the pit 26 of the uneven signal portion. As mentioned above, the signal is recorded on the tracking track section 24 shown by diagonal lines.
本発明の記録担体を使用する光学式記録再生装
置について第３図と共に説明する。 An optical recording/reproducing apparatus using the record carrier of the present invention will be explained with reference to FIG.
記録担体１はデイスクモータ４１の回転軸に取
り付けられて所定の回転数で回転されている。半
導体レーザ等の光源４２より発生した光ビーム４
３は、カツプリングレンズ４４で平行光にされ、
偏光ビームスプリツター４５及び1/4波長板４６
を通過し、反射鏡４７で反射され、収束レンズ４
８により記録担体１上に収束される。記録担体１
より反射された光ビーム４３は再び収束レンズ４
８を通過し、反射鏡４７により反射され、1/4波
長板４６を通過し、偏光ビームスプリツター４５
で反射されて光検出器４９上に照射される。光検
出器４９は２分割構造になつており、その分割線
の方向は光検出器４９上におけるトラツク方向と
なつている。 The record carrier 1 is attached to the rotating shaft of a disk motor 41 and rotated at a predetermined number of rotations. A light beam 4 generated from a light source 42 such as a semiconductor laser
3 is made into parallel light by a coupling lens 44,
Polarizing beam splitter 45 and 1/4 wavelength plate 46
, is reflected by the reflecting mirror 47, and is reflected by the converging lens 4.
8 onto the record carrier 1. Record carrier 1
The more reflected light beam 43 passes through the converging lens 4 again.
8, is reflected by a reflecting mirror 47, passes through a 1/4 wavelength plate 46, and is polarized by a polarizing beam splitter 45.
The light is reflected and irradiated onto the photodetector 49. The photodetector 49 has a two-part structure, and the direction of the dividing line is the track direction on the photodetector 49.
光検出器４９の２つの出力は差動増幅器５０に
それぞれ入力されており、差動増幅器５０は両入
力信号の差を出力する。差動増幅器５０の信号が
記録担体１上の光ビーム４３とトラツクの位置ず
れを表わす信号すなわちトラツキング制御信号と
なることは既知であり詳述するのを避ける。 The two outputs of the photodetector 49 are respectively input to a differential amplifier 50, and the differential amplifier 50 outputs the difference between the two input signals. It is well known that the signal from the differential amplifier 50 is a tracking control signal that represents the positional deviation between the optical beam 43 and the track on the record carrier 1, and will not be described in detail.
差動増幅器５０の信号はトラツキング制御系の
位相を補償する為の位相補償回路５１、電力増幅
する駆動回路５２を介してトラツキング素子５３
に加えられる。収束レンズ４８はトラツキング素
子５３に取り付けられており、トラツキング素子
５３は収束レンズ４８を記録担体１上のトラツク
方向と垂直な方向に移動出来るように構成されて
いる。 The signal from the differential amplifier 50 is sent to the tracking element 53 via a phase compensation circuit 51 for compensating the phase of the tracking control system and a drive circuit 52 for power amplification.
added to. The converging lens 48 is attached to a tracking element 53, and the tracking element 53 is configured to move the converging lens 48 in a direction perpendicular to the direction of tracks on the record carrier 1.
従つて収束レンズ４８は差動増幅器５０の信号
に応じて移動し、記録担体１上の光ビーム４３が
トラツク上を常に走査するようにトラツキング制
御される。 Therefore, the converging lens 48 moves in accordance with the signal from the differential amplifier 50, and tracking is controlled so that the light beam 43 on the record carrier 1 always scans the track.
凹凸信号部の信号検出について説明すると、光
検出器４９の２つの出力は合成回路５４にそれぞ
れ入力されており、合成回路５４は両信号を合成
した信号を出力し、図面では省略しているが、合
成回路５４の信号を処理して番地あるいはセクタ
ー等の情報を得ている。 To explain the signal detection of the uneven signal section, the two outputs of the photodetector 49 are respectively input to a combining circuit 54, and the combining circuit 54 outputs a signal that is a combination of both signals, although it is omitted in the drawing. , the signals from the combining circuit 54 are processed to obtain information such as addresses or sectors.
信号を記録する場合、先ず番地あるいはセクタ
ー等の情報より信号を記録するトラツク領域を確
認し、光ビーム４の強度を記録する信号に応じて
変化させ記録する。 When recording a signal, first the track area in which the signal is to be recorded is confirmed from information such as an address or sector, and the intensity of the light beam 4 is changed in accordance with the signal to be recorded.
凹凸信号部のピツト形状と合成回路５４の信号
の関係について第４図と共に説明する。第４図ａ
は記録担体１上の光ビーム４３と幅が狭いビツト
２６を示しており、ｂはａにおいて光ビーム４３
がピツト２６上を走査した時の合成回路５４の信
号波形を示している。ｃ及びｄはピツト２６の幅
が広い場合の説明図である。ｃは光ビーム４３と
幅の広いピツト６３及び６４を示しており、ｄは
ｃにおいて光ビーム４３がピツト６３，６４上を
走査した時の合成回路５４の信号波形を示してい
る。ｂとｄを比較すると、ピツト幅が狭い場合に
は６１のように長いピツトでも６２のように短か
いピツトでも良好な信号が得られるが、ピツト幅
が広い場合には、６３のように長いピツトほど信
号の品質が低下し、検出が困難となることが判
る。凹凸信号部からの再生信号はピツトのエツジ
で光ビームが回析する為に得られるものであり、
幅が狭い方が良好な信号が得られる。 The relationship between the pit shape of the uneven signal section and the signal of the combining circuit 54 will be explained with reference to FIG. 4. Figure 4a
b shows the light beam 43 on the record carrier 1 and the narrow bit 26, and b shows the light beam 43 at a.
5 shows the signal waveform of the combining circuit 54 when scanning the pit 26. c and d are explanatory diagrams when the width of the pit 26 is wide. c shows the light beam 43 and wide pits 63 and 64, and d shows the signal waveform of the combining circuit 54 when the light beam 43 scans over the pits 63 and 64 in c. Comparing b and d, if the pit width is narrow, a good signal can be obtained with a long pit like 61 or a short pit like 62, but if the pit width is wide, a long pit like 63 will give a good signal. It can be seen that the closer the pits are, the lower the quality of the signal is and the more difficult it is to detect. The reproduced signal from the uneven signal section is obtained because the light beam is diffracted at the edge of the pit.
The narrower the width, the better the signal.
トラツク幅とトラツキング信号の関係について
第５図と共に説明する。第５図ａは光ビーム４３
とトラツク２２の関係を示しており、ｆはｅにお
いて光ビーム４３をトラツク方向と垂直な方向、
すなわち矢印７１の方向に移動させた時の前記差
動増幅器５０の信号波形を示している。トラツク
２２の幅が広い場合には曲線７２のような波形と
なり第５図ａに破線で示した７３のようにトラツ
ク幅が狭い場合には第５図ｂに破線で示した曲線
７４のような波形となる。曲線７２及び７３にお
いて信号出力が最大値になる点と最小値になる点
の範囲をそれぞれ７５と７６で示しているが、ト
ラツク幅が広いほど範囲が広くなる。従つてトラ
ツキング制御系のループゲインを一定とすると、
前記範囲が広いほど外乱に対して強くなる。 The relationship between the track width and the tracking signal will be explained with reference to FIG. Figure 5a shows the light beam 43.
and the track 22, where f directs the light beam 43 at e in a direction perpendicular to the track direction;
That is, it shows the signal waveform of the differential amplifier 50 when it is moved in the direction of an arrow 71. When the width of the track 22 is wide, the waveform becomes a curve 72, and when the track width is narrow, it becomes a curve 74 shown as a broken line in FIG. 5b. It becomes a waveform. The ranges of the points at which the signal output reaches its maximum value and its minimum value on the curves 72 and 73 are indicated by 75 and 76, respectively, and the wider the track width, the wider the range. Therefore, if the loop gain of the tracking control system is constant,
The wider the range, the stronger the resistance to disturbance.
本発明の記録担体において、凹凸の信号部のピ
ツト幅が狭いのでトラツク飛が生じやすいように
思われるが、実際の場合、光ビームが凹凸の信号
部上を走査する時間は非常に短かく例えば数十
μsec程度であり、ピツト幅を狭くしても何ら問題
はない。 In the record carrier of the present invention, it seems that track skipping is likely to occur because the pit width of the uneven signal area is narrow, but in reality, the time for the light beam to scan over the uneven signal area is very short. It is about several tens of microseconds, and there is no problem even if the pit width is narrowed.
発明の効果
以上本発明を詳細に説明したが、本発明の光学
式情報記録担体を使用すれば、振動あるいは衝撃
等の外乱に対してトラツク飛びが少ないトラツキ
ング制御系を構成できると共に、番地あるいはセ
クター等凹凸形状のピツトで記録されている凹凸
信号部からの再生信号も良好に検出することが出
来る。Effects of the Invention The present invention has been described in detail above. By using the optical information recording carrier of the present invention, it is possible to construct a tracking control system with less track skipping due to disturbances such as vibrations or shocks, and to track addresses or sectors. It is also possible to detect satisfactorily a reproduced signal from a concavo-convex signal portion recorded with pits having an evenly concavo-convex shape.
第１図は本発明の光学式情報記録担体の一実施
例の平面図、第２図は第１図の１部分の拡大斜視
図、第３図は本発明の光学式情報記録担体を使用
する光学式記録再生装置の例を示すブロツク図、
第４図は光学式情報記録担体上の光ビームとピツ
ト幅の関係の説明図、第５図は光学式情報記録担
体上の光ビームとトラツク幅の関係の説明図であ
る。
１……記録担体、３……追跡トラツク部の領
域、４……凹凸信号部の領域、２２……トラツ
ク、２３……記録材料層、２４……追跡トラツク
部、２５……追跡トラツク部の深さ、２６……ピ
ツト、２７……ピツトの深さ、２８……トラツク
方向、２９……追跡トラツク部の幅、３０……ピ
ツトの幅。
FIG. 1 is a plan view of an embodiment of the optical information recording carrier of the present invention, FIG. 2 is an enlarged perspective view of a portion of FIG. 1, and FIG. 3 is a plan view of an embodiment of the optical information recording carrier of the present invention. A block diagram showing an example of an optical recording/reproducing device,
FIG. 4 is an explanatory diagram of the relationship between the light beam and pit width on the optical information recording carrier, and FIG. 5 is an explanatory diagram of the relationship between the light beam and the track width on the optical information recording carrier. DESCRIPTION OF SYMBOLS 1...Record carrier, 3...Region of tracking track portion, 4...Region of uneven signal portion, 22...Track, 23...Recording material layer, 24...Tracking track portion, 25...Region of tracking track portion Depth, 26... Pit, 27... Pit depth, 28... Track direction, 29... Width of tracking track portion, 30... Pit width.
Claims (1)
用トラツク上に信号を記録するようにした光学式
記録担体において、前記追跡用トラツクの位置を
識別する為に設けられている凹凸のピツト列より
成る識別信号のピツト幅を前記追跡用トラツクの
幅よりも狭くしたことを特徴とする光学式情報記
録担体。 ２ トラツクの深さを光路長が光ビームの波長の
約1/8になるようにしたことを特徴とした特許請
求の範囲第１項記載の光学式情報記録担体。[Claims] 1. An optical record carrier in which a signal is recorded on a concave or convex tracking track for tracking a light beam, which is provided to identify the position of the tracking track. 1. An optical information recording carrier characterized in that the pit width of the identification signal consisting of a row of uneven pits is narrower than the width of the tracking track. 2. The optical information recording carrier according to claim 1, wherein the depth of the track is such that the optical path length is approximately 1/8 of the wavelength of the light beam.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58228731A JPS60121550A (en) | 1983-12-02 | 1983-12-02 | Optical information recording carrier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58228731A JPS60121550A (en) | 1983-12-02 | 1983-12-02 | Optical information recording carrier |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60121550A JPS60121550A (en) | 1985-06-29 |
| JPH0452536B2 true JPH0452536B2 (en) | 1992-08-24 |
Family
ID=16880925
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58228731A Granted JPS60121550A (en) | 1983-12-02 | 1983-12-02 | Optical information recording carrier |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60121550A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3135389B2 (en) * | 1992-10-23 | 2001-02-13 | 松下電器産業株式会社 | Information reproducing method, information recording / reproducing method, information reproducing apparatus, recording medium, and optical head |
| US5508995A (en) * | 1993-07-15 | 1996-04-16 | Matsushita Electric Industrial Co., Ltd. | Optical disk capable of recording information on both groove and land tracks |
| JP2863431B2 (en) * | 1994-01-31 | 1999-03-03 | シャープ株式会社 | Magneto-optical recording / reproducing device |
| JP2566111B2 (en) * | 1994-01-31 | 1996-12-25 | シャープ株式会社 | Magneto-optical memory device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5930251A (en) * | 1982-08-10 | 1984-02-17 | Toshiba Corp | Optical information storage medium |
-
1983
- 1983-12-02 JP JP58228731A patent/JPS60121550A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5930251A (en) * | 1982-08-10 | 1984-02-17 | Toshiba Corp | Optical information storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60121550A (en) | 1985-06-29 |
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