JPH0782649B2 - Light beam precision positioning device - Google Patents
Light beam precision positioning deviceInfo
- Publication number
- JPH0782649B2 JPH0782649B2 JP58039273A JP3927383A JPH0782649B2 JP H0782649 B2 JPH0782649 B2 JP H0782649B2 JP 58039273 A JP58039273 A JP 58039273A JP 3927383 A JP3927383 A JP 3927383A JP H0782649 B2 JPH0782649 B2 JP H0782649B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- optical sensor
- optical system
- light beam
- reflecting member
- 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
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
- G11B7/08—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
- G11B7/0925—Electromechanical actuators for lens positioning
Landscapes
- Mechanical Optical Scanning Systems (AREA)
- Optical Recording Or Reproduction (AREA)
Description
【発明の詳細な説明】 〔発明の利用分野〕 本発明はデイスク上の情報トラツクに情報を光学的に書
き込んだり読み出したりする装置に係り、特に目標とす
る情報トラツクに光ビームを精密に位置決めするのに好
適な電磁式ビーム偏向装置に関する。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for optically writing and reading information to and from an information track on a disk, and in particular, precisely positions a light beam on a target information track. The present invention relates to an electromagnetic beam deflecting device suitable for
従来のビーム偏向装置の構造を第１図の斜視図を用いて
説明する。本体１に磁石2a,2bをはさんだヨーク3a,3bと
3c,3dが取付けられており、ヨーク3a,3bおよび3c,3dの
先端の間隙には駆動コイル４が磁速を横切る形で挿入さ
れている。この駆動コイル４には光ビーム偏向用の可動
鏡５が取付けられており、電流を流すことによつて可動
鏡５の角度を変え光ビームの偏向を行う。第２図は平面
から見た図を示し、矢印101が可動鏡５の回転方向とな
る。The structure of a conventional beam deflector will be described with reference to the perspective view of FIG. Yokes 3a and 3b with magnets 2a and 2b sandwiched in the body 1
3c and 3d are attached, and a drive coil 4 is inserted across the magnetic speed in the gap between the tips of the yokes 3a and 3b and 3c and 3d. A movable mirror 5 for deflecting the light beam is attached to the drive coil 4, and the angle of the movable mirror 5 is changed by passing a current to deflect the light beam. FIG. 2 shows a plan view, and the arrow 101 indicates the direction of rotation of the movable mirror 5.
この構造において所定の角度だけ光ビームの方向を変え
ようとした場合、サーボ系によつて可動鏡５の位置決め
を行うわけだが、ダンピング効果が小さいと静定時間が
長くかかり、また発振しやすくなるためサーボ系による
補償に負担がかかる欠点があつた。また、外乱による振
動、たとえば光ヘツドの移動に伴う振動や装置に物がぶ
つかつた時の振動が可動鏡５に伝わつた場合、振動によ
つて生じた角度ずれがなかなか静定しない欠点があり、
トラツク位置決めがその間行えず、性能として低いもの
になる欠点があつた。In this structure, when it is attempted to change the direction of the light beam by a predetermined angle, the movable mirror 5 is positioned by the servo system. However, if the damping effect is small, it takes a long time to settle and oscillation easily occurs. Therefore, there is a drawback that compensation is required by the servo system. Further, when vibration due to disturbance, for example, vibration due to movement of an optical head or vibration when an object hits the device is transmitted to the movable mirror 5, there is a drawback that the angular deviation caused by the vibration is not easily settled. ,
Track positioning cannot be performed during that time, resulting in poor performance.
本発明の目的は減衰効果を高め、位置決め性能を向上さ
せた光デイスクのトラツク位置決めに好適な電磁式ビー
ム偏向装置を提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide an electromagnetic beam deflector suitable for track positioning of an optical disc, which has improved damping effect and improved positioning performance.
可動鏡は板ばねの弾性変形によつてその角度を替えるこ
とができるが、減衰効果が小さいと外乱などで角度ずれ
を起こしやすくなるためその対策が必要となる。そこ
で、回路定数を変えることで減衰定数を簡単に変えるこ
とのできる電気的減衰法を考えた。本発明では、光ビー
ムを照射して、記録媒体上のトラックに沿って情報を光
学的に書き込み、また、情報を光学的に読み出す装置に
おいて、光ビームを位置決めするための可動鏡などの可
動光学系と、この可動光学系を駆動する駆動コイルなど
の駆動機構と、１つの発光素子及び１つの受光素子を有
し可動光学系の変位を検出する光センサと、受光素子の
出力から可動光学系の速度信号を作り出す変換手段とを
有し、発光素子及び受光素子はその位置関係を固定した
一体型の光センサとして構成される。光センサの発光素
子から出射した光は、例えば可動光学系に固定された駆
動コイルの取付板に接着された反射鏡で反射した後に、
受光素子に入射する。この場合、可動光学系が変位する
と反射鏡が動き光の光路が変わるので、変位量に従って
受光素子に入射する光の光量が変化し、受光素子からの
出力信号が変化する。この出力信号の変化の度合いが、
可動光学系の変位と受光素子の出力信号の関係が直線
的、すなわち、比例関係になるように光センサの配置を
調整し、可動光学系の位置信号を検出する。発光素子と
受光素子が一体となっているので、配置の調整は容易で
ある。その後、位置信号より微分回路を通し速度信号を
作り、それを駆動コイル入力に負帰還をかけ減衰効果を
得るものである。The angle of the movable mirror can be changed by elastic deformation of the leaf spring, but if the damping effect is small, the angle shift is likely to occur due to disturbance or the like, so a countermeasure is required. Therefore, we considered an electric damping method that can easily change the damping constant by changing the circuit constant. In the present invention, in a device that irradiates a light beam to optically write information along a track on a recording medium and optically read information, a movable optical device such as a movable mirror for positioning the light beam is used. System, a drive mechanism such as a drive coil for driving the movable optical system, an optical sensor having one light emitting element and one light receiving element for detecting displacement of the movable optical system, and a movable optical system based on the output of the light receiving element The light emitting element and the light receiving element are configured as an integrated optical sensor whose positional relationship is fixed. The light emitted from the light emitting element of the optical sensor is reflected by, for example, a reflecting mirror adhered to a mounting plate of a drive coil fixed to the movable optical system,
It is incident on the light receiving element. In this case, when the movable optical system is displaced, the reflecting mirror moves and the optical path of the light changes, so that the amount of light incident on the light receiving element changes according to the amount of displacement and the output signal from the light receiving element changes. The degree of change in this output signal is
The position of the movable optical system is detected by adjusting the arrangement of the optical sensor so that the displacement of the movable optical system and the output signal of the light receiving element have a linear or proportional relationship. Since the light emitting element and the light receiving element are integrated, the arrangement can be easily adjusted. After that, a velocity signal is generated from the position signal through a differentiating circuit, and the feedback signal is negatively fed back to the input of the driving coil to obtain a damping effect.
以下本発明の一実施例を第３図，第４図及び第５図によ
り説明する。第３図は一実施例の斜視図である。可動鏡
５の位置決めを行う駆動コイル４は取付板６に付いてい
るが、この取付板６に反射鏡10を接着剤その他の方法で
貼付ける。第４図に示す如く、この反射鏡10と対向して
取付ブロツク８に、反射型の光センサ７が取付ネジ９に
よつて取付けられる。光センサ７は発光部と受光部を兼
ね備えたものである。反射鏡10と光センサ７の距離は可
動鏡５の定常状態において変位と出力の関係が直線的に
なつている区間の中点に来るように取付ネジ９によつて
調整する。第５図に光センサ10の検出回路を示す。光セ
ンサ10には発光部11と受光部12がコンパクトに組み込ま
れており、発光部11は電源13−ａに応じた光を発し、そ
れは反射鏡10によつて反射し受光部12に入射する。反射
鏡10は前後の方向102に移動するため、その位置に応じ
て受光部12への入射光量が変化する。電源13−ｂによつ
て駆動される受光部12に光が入射することによつて出力
が発生し、その出力は増幅器14,15,16、抵抗Ｒ、コンデ
ンサＣなどによりなる微分回路に入ることにより位置信
号から速度信号Ｖに変わる。この速度信号Ｖを可動鏡10
の駆動コイル４の入力に負帰還をかけることによりダン
ピング効果が実現できる。この時、発光部11の発光光量
を変化させるため電源13−ａの電圧を変えたり、回路の
利得を変化させることによつてダンピング効果を増減さ
せ、最低なダンピングの状態となるように調整する。ま
たこの回路において発光部11と受光部12を別電源で駆動
している理由は検出信号のノイズを低減させるものでも
ある。本実施例によればダンピング係数任意に調整でき
るため可動鏡５の最適なダンピングが容易に実現でき、
このダンピング効果によつてサーボ系が働いた状態で可
動鏡５は外部からの振動に強い安定した動作を得ること
ができ、位置決め性能が向上するという効果がある。An embodiment of the present invention will be described below with reference to FIGS. 3, 4, and 5. FIG. 3 is a perspective view of one embodiment. The drive coil 4 for positioning the movable mirror 5 is attached to the mounting plate 6, and the reflecting mirror 10 is attached to the mounting plate 6 with an adhesive or other method. As shown in FIG. 4, the reflection type optical sensor 7 is attached to the attachment block 8 by the attachment screw 9 so as to face the reflecting mirror 10. The optical sensor 7 has both a light emitting portion and a light receiving portion. The distance between the reflecting mirror 10 and the optical sensor 7 is adjusted by the mounting screw 9 so that the movable mirror 5 comes to the midpoint of the section where the relationship between displacement and output is linear in the steady state. FIG. 5 shows a detection circuit of the optical sensor 10. A light emitting portion 11 and a light receiving portion 12 are compactly incorporated in the optical sensor 10, and the light emitting portion 11 emits light corresponding to the power source 13-a, which is reflected by the reflecting mirror 10 and enters the light receiving portion 12. . Since the reflecting mirror 10 moves in the front-back direction 102, the amount of light incident on the light receiving unit 12 changes depending on the position. When light is incident on the light receiving portion 12 driven by the power supply 13-b, an output is generated, and the output is to enter a differentiating circuit including amplifiers 14, 15, 16 and resistors R and C. Causes the position signal to change to the speed signal V. This speed signal V is applied to the movable mirror 10
A damping effect can be realized by applying a negative feedback to the input of the drive coil 4. At this time, the damping effect is increased or decreased by changing the voltage of the power supply 13-a or the gain of the circuit in order to change the amount of light emitted from the light emitting section 11, and adjustment is made so as to obtain the minimum damping state. . Further, the reason why the light emitting section 11 and the light receiving section 12 are driven by different power sources in this circuit is also to reduce the noise of the detection signal. According to the present embodiment, since the damping coefficient can be adjusted arbitrarily, optimum damping of the movable mirror 5 can be easily realized,
Due to this damping effect, the movable mirror 5 can obtain a stable operation that is strong against external vibration while the servo system is working, and the positioning performance is improved.
第６図は光センサ７の取付ブロツクを省略した一実施例
であり、可動鏡５を支持するための板ばね19を固定する
取付け部材20と光センサ７の取付けブロツクを兼用した
形となつており取付けネジ９によつて固定される。本実
施例によれば取付けブロツクが省略でき、部品点数を低
減できる効果がある。また本構造は磁石17−a,17−ｂが
両わきとなるため薄形の形状が可能となる。FIG. 6 shows an embodiment in which the mounting block for the optical sensor 7 is omitted. The mounting block for mounting the optical sensor 7 and the mounting member 20 for fixing the leaf spring 19 for supporting the movable mirror 5 are combined. It is fixed by a cage mounting screw 9. According to this embodiment, the mounting block can be omitted, and the number of parts can be reduced. In addition, this structure allows the magnets 17-a and 17-b to have a thin shape because they are provided on both sides.
第７図及び第８図は光センサの位置の調整方法を迅速に
行うための他の実施例である。第３図と第６図の実施例
においては止めネジ９によつて光センサ７の位置決めを
行つているが、その調整方法としては光センサ７の出力
レベルをモニターしながら手で光センサ７の位置をずら
して最適な位置へ移動させなければならず、移動させ、
止めるという２つの動作を行う必要があつた。本実施例
はその調整方法を簡便にした発明であり、第８図に光セ
ンサ部の断面図を示す。光センサ７はリード線26を固定
し、かつ光センサ径と等しいホルダ24と一体となつてい
る。その光センサ７は取付けブロツク21内部に組み込ま
れたコイルバネ23の円周で案内され、ホルダ24のフラン
ジ部とコイルバネ23が当たる所で止まる。この状態で取
付けブロツク21に調整ネジ板23を取付け、調整ネジ25を
回転させコイルバネ23に予圧しつつ、光センサ７の位置
を移動させていく。このようにして反射鏡10との最適な
位置まで調整ネジを回転させる。調整ネジ25にはコイル
バネ23の予圧が加わつておりゆるみ止めとなる。また取
付けブロツク21は反射鏡10の上部を覆う形状となつてい
る。これは光センサ７を使用する際に問題となる外部か
らの入射光を遮る目的で考えた形状であり、たとえば螢
光灯の光が入射することによつて50Hzおよびその倍周波
数のノイズが信号の中に現われ、周波数特性が悪くな
る。この欠点を解消するために本実施例の形状とすれ
ば、ノイズの少い速度信号を得ることが可能となる。本
実施例によれば光センサ７の位置決めが容易に行え、光
センサ７の外乱の原因となる外部からの光の入射を十分
遮断でき、ノイズの少い位置信号検出が行える効果があ
る。7 and 8 show another embodiment for speedily performing the method of adjusting the position of the optical sensor. In the embodiment shown in FIGS. 3 and 6, the optical sensor 7 is positioned by the setscrew 9. However, as an adjusting method, the optical sensor 7 can be manually adjusted while monitoring the output level of the optical sensor 7. You have to shift the position and move it to the optimum position, move it,
It was necessary to perform two actions of stopping. The present embodiment is an invention in which the adjusting method is simplified, and FIG. 8 shows a sectional view of the optical sensor portion. The optical sensor 7 fixes the lead wire 26 and is integrated with the holder 24 having the same diameter as the optical sensor. The optical sensor 7 is guided by the circumference of a coil spring 23 incorporated inside the mounting block 21, and stops when the flange portion of the holder 24 and the coil spring 23 come into contact with each other. In this state, the adjusting screw plate 23 is attached to the attaching block 21, and the adjusting screw 25 is rotated to preload the coil spring 23 while moving the position of the optical sensor 7. In this way, the adjusting screw is rotated to the optimum position with respect to the reflecting mirror 10. The adjusting screw 25 is preloaded by the coil spring 23 to prevent it from loosening. The mounting block 21 is shaped so as to cover the upper part of the reflecting mirror 10. This is a shape designed to block incident light from the outside, which is a problem when using the optical sensor 7. For example, when the light of a fluorescent lamp is incident, noise of 50 Hz and its double frequency becomes a signal. Appears in the, and the frequency characteristics deteriorate. If the shape of this embodiment is adopted to eliminate this drawback, it is possible to obtain a velocity signal with little noise. According to the present embodiment, the optical sensor 7 can be easily positioned, the incident light from the outside which causes the disturbance of the optical sensor 7 can be sufficiently blocked, and the position signal with less noise can be detected.
本発明によれば減衰定数は自由に設定することができる
ため、装置に合わせて最適に設定することによつて外部
振動に強くなり、位置決め時間を短縮でき、性能が向上
し、確実に情報トラツクに位置決めが行えるという効果
がある。According to the present invention, since the damping constant can be freely set, by setting it optimally according to the device, it becomes resistant to external vibration, the positioning time can be shortened, the performance is improved, and the information track is reliably performed. There is an effect that the positioning can be performed at.
第１図は従来技術の電磁式ビーム偏向装置の斜視図、第
２図はその要部の平面図、第３図は一実施例の斜視図、
第４図は光センサ部の拡大図、第５図は光センサの検出
回路、第６図は他の実施例を示す図、第７図は他の実施
例の斜視図、第８図はその断面図である。 １……本体、2a,2b……磁石、3a,3b,3c,3d……ヨーク、
４……駆動コイル、５……可動鏡、６……取付板、７…
…光センサ、８……取付ブロツク、９……取付ネジ、10
……反射鏡、101……ミラー回転方向、102……反射鏡移
動方向、11……発光部、12……受光部、13−a,13−ｂ…
…電源、14,15,16……増幅器、Ｃ……コンデンサ、Ｒ…
…抵抗、Ｖ……速度信号、17−a,17−ｂ……磁石、18…
…可動鏡取付台、19……板ばね、20……取付け部材、21
……取付ブロツク、22……調整ネジ板、23……コイルば
ね、24……ホルダ、25……調整ネジ、26……リード線。FIG. 1 is a perspective view of a conventional electromagnetic beam deflector, FIG. 2 is a plan view of an essential part thereof, and FIG. 3 is a perspective view of an embodiment,
FIG. 4 is an enlarged view of the optical sensor section, FIG. 5 is a detection circuit of the optical sensor, FIG. 6 is a view showing another embodiment, FIG. 7 is a perspective view of another embodiment, and FIG. FIG. 1 ... Main body, 2a, 2b ... Magnet, 3a, 3b, 3c, 3d ... Yoke,
4 ... Drive coil, 5 ... Movable mirror, 6 ... Mounting plate, 7 ...
… Optical sensor, 8 …… Mounting block, 9 …… Mounting screw, 10
...... Reflector, 101 ...... Mirror rotation direction, 102 ・ ・ ・ Reflector movement direction, 11 …… Light emitting part, 12 …… Light receiving part, 13-a, 13-b ...
… Power supply, 14,15,16 …… Amplifier, C …… Capacitor, R…
... resistance, V ... speed signal, 17-a, 17-b ... magnet, 18 ...
… Movable mirror mount, 19 …… Leaf spring, 20 …… Mounting member, 21
...... Mounting block, 22 …… Adjustment screw plate, 23 …… Coil spring, 24 …… Holder, 25 …… Adjustment screw, 26 …… Lead wire.
フロントページの続き (72)発明者 金田 徳也 神奈川県小田原市国府津2880番地 株式会 社日立製作所小田原工場内 (56)参考文献 特開 昭51−61726（ＪＰ，Ａ) 特開 昭52−48912（ＪＰ，Ａ) 特開 昭54−96231（ＪＰ，Ａ) 特開 昭55−150137（ＪＰ，Ａ) 特開 昭55−153138（ＪＰ，Ａ) 特開 昭57−123793（ＪＰ，Ａ)Front page continuation (72) Inventor Tokuya Kaneda 2880, Kozu, Odawara-shi, Kanagawa Inside the Odawara Plant, Hitachi Ltd. (56) References JP-A-51-61726 (JP, A) JP-A-52-48912 (JP) , A) JP 54-96231 (JP, A) JP 55-150137 (JP, A) JP 55-153138 (JP, A) JP 57-123793 (JP, A)
Claims (1)
クに沿って情報を光学的に書き込み、また、情報を光学
的に読み出す装置において、上記光ビームを位置決めす
る可動光学系と、該可動光学系を駆動する駆動機構と、
上記可動光学系に固着された反射部材と、上記反射部材
に光を照射する１つの発光素子及び上記反射部材によっ
て反射された上記発光素子からの光を受光する１つの受
光素子とが一体に構成され、かつ上記受光素子の出力信
号と上記反射部材の変位との関係が直線となる範囲内に
位置するように上記反射部材と対向配置された光センサ
と、上記光センサの出力を微分する微分回路とを有し、
上記光センサから出力される上記可動光学系の変位信号
を上記微分回路によって上記可動光学系の速度信号に変
換し、上記速度信号に基づいて上記駆動機構をフィード
バック制御することを特徴とする光ビーム精密位置決め
装置。1. A movable optical system for positioning a light beam in an apparatus for irradiating a light beam to optically write information along a track on a recording medium and to optically read information, and A drive mechanism for driving the movable optical system,
A reflecting member fixed to the movable optical system, one light emitting element that irradiates the reflecting member with light, and one light receiving element that receives the light from the light emitting element reflected by the reflecting member are integrally configured. And an optical sensor that is arranged so as to face the reflecting member so that the relationship between the output signal of the light receiving element and the displacement of the reflecting member is located within a linear range, and a differentiation that differentiates the output of the optical sensor. Has a circuit and
A light beam characterized by converting a displacement signal of the movable optical system output from the optical sensor into a velocity signal of the movable optical system by the differentiating circuit, and performing feedback control of the drive mechanism based on the velocity signal. Precision positioning device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58039273A JPH0782649B2 (en) | 1983-03-11 | 1983-03-11 | Light beam precision positioning device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58039273A JPH0782649B2 (en) | 1983-03-11 | 1983-03-11 | Light beam precision positioning device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59165252A JPS59165252A (en) | 1984-09-18 |
| JPH0782649B2 true JPH0782649B2 (en) | 1995-09-06 |
Family
ID=12548547
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58039273A Expired - Lifetime JPH0782649B2 (en) | 1983-03-11 | 1983-03-11 | Light beam precision positioning device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0782649B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5446712A (en) * | 1991-04-22 | 1995-08-29 | Seiko Epson Corporation | Optical system having a precision angular displacement mechanism including a flat metal spring |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL174609C (en) * | 1975-10-15 | 1984-07-02 | Philips Nv | TRACK MIRROR IN AN OPTICAL RECORD PLAYER. |
| JPS55150137A (en) * | 1979-05-09 | 1980-11-21 | Matsushita Electric Ind Co Ltd | Recorder |
-
1983
- 1983-03-11 JP JP58039273A patent/JPH0782649B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59165252A (en) | 1984-09-18 |
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