JP3131798B2 - Optical pickup device - Google Patents
Optical pickup deviceInfo
- Publication number
- JP3131798B2 JP3131798B2 JP04044720A JP4472092A JP3131798B2 JP 3131798 B2 JP3131798 B2 JP 3131798B2 JP 04044720 A JP04044720 A JP 04044720A JP 4472092 A JP4472092 A JP 4472092A JP 3131798 B2 JP3131798 B2 JP 3131798B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- optical
- optical path
- reflected
- laser
- 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 - Fee Related
Links
Landscapes
- Optical Head (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、光学的情報記録再生装
置等に用いる光ピックアップ装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device used for an optical information recording / reproducing device and the like.
【０００２】[0002]
【従来の技術】光ピックアップ光学系装置としては、実
開平１−174721号公報に開示されたものがある。この内
容は、光源の前方に偏光ビームスプリッタを設け、その
前面にコリメータレンズおよびミラーを配設し、このミ
ラーの反射方向に対物レンズを設けて前記光源の光線を
対物レンズにて光ディスク上に集光するとともに、前記
偏光ビームスプリッタの側方にセンサーレンズを設け、
このセンサーレンズの後方にトラッキングおよびフォー
カス双方のエラーを同時に検出できるホトダイオードを
設け、光ディスクからの反射光がホトダイオードで受光
できるようにしたものである。2. Description of the Related Art As an optical system for an optical pickup, there is one disclosed in Japanese Utility Model Laid-Open No. 1-174721. The contents are as follows. A polarizing beam splitter is provided in front of the light source, a collimator lens and a mirror are provided in front of the light source, and an objective lens is provided in the reflection direction of the mirror, and the light beam of the light source is collected on the optical disk by the objective lens. Along with light, a sensor lens is provided on the side of the polarizing beam splitter,
A photodiode that can detect both tracking and focus errors at the same time is provided behind the sensor lens so that light reflected from the optical disk can be received by the photodiode.
【０００３】また従来の光ピックアップにおいて、ビー
ムスプリッタ等の光学部品は一般に接着により固定され
ていた。In a conventional optical pickup, optical components such as a beam splitter are generally fixed by bonding.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、接着に
より固定された光学部品は温度変化や経時変化等の環境
変化で微小な変位を生じることが知られており、この微
小な変位が信号検出に誤差を与える。また、レーザダイ
オードから出射したレーザ光は、記録媒体に到達する間
に光学部品の透過，反射面を通過するたびにレーザ光の
収差が悪化し、記録媒体に結像するレーザスポットの性
能に影響を与える。この影響は反射面を通過した場合に
特に顕著である。さらに記録媒体から反射された信号を
含んだレーザ光は、光学部品の透過面，反射面，偏光面
を通過するたびに、信号の位相差が発生したり収差の悪
化が生じ信号の劣化を生じる。上記のいずれの場合も信
号の劣化を生じ記録再生能力が劣化するという問題があ
る。なお、実開平１−174721号公報の従来例では、ビー
ムスプリッタの角度が変位した場合にビームスプリッタ
の偏光反射面の角度が変化し、検出系への光路が変化す
る問題を有している。However, it is known that an optical component fixed by bonding causes a minute displacement due to an environmental change such as a temperature change or a temporal change, and this small displacement causes an error in signal detection. give. In addition, the laser light emitted from the laser diode deteriorates the aberration of the laser light each time it passes through the transmission and reflection surfaces of the optical components while reaching the recording medium, and affects the performance of the laser spot formed on the recording medium. give. This effect is particularly remarkable when the light passes through the reflecting surface. Further, every time the laser beam including the signal reflected from the recording medium passes through the transmission surface, the reflection surface, and the polarization surface of the optical component, a phase difference of the signal is generated or the aberration is deteriorated, so that the signal is deteriorated. . In any of the above cases, there is a problem that the signal is deteriorated and the recording / reproducing ability is deteriorated. In the conventional example of Japanese Utility Model Laid-Open No. 1-174721, there is a problem that when the angle of the beam splitter is displaced, the angle of the polarization reflection surface of the beam splitter changes, and the optical path to the detection system changes.
【０００５】本発明は、上記従来の問題を解決するもの
であり、光学レイアウトを最適化し、記録再生能力の劣
化を最小に抑え、かつ小型化を図った光ピックアップ装
置を提供することを目的とするものである。An object of the present invention is to solve the above-mentioned conventional problems and to provide an optical pickup device which optimizes an optical layout, minimizes deterioration of recording / reproducing ability, and is miniaturized. Is what you do.
【０００６】[0006]
【課題を解決するための手段】上記目的を達成するため
に本発明の光ピックアップ装置は、光学的情報記録再生
装置に用いられる光ピックアップ装置であって、レーザ
ダイオードから出射するレーザ光をカップリングレンズ
により平行光にし、この平行光をビームスプリッタ内で
反射させ、この反射光をビームスプリッタの反射／透過
分割面に入射させて、反射光路である第１の光路と透過
光路である第２の光路へ分割させ、分割された第１の光
路におけるレーザ光をレーザダイオード光量制御のため
に受光素子に入射させ、分割された第２の光路における
レーザ光を対物レンズにより記録媒体に集光させ、この
記録媒体にて反射したレーザ光を前記第２の光路を逆に
進ませ、かつビームスプリッタの前記反射／透過分割面
で反射させて第３の光路に出射させる構成にし、さらに
前記平行光の中心光軸と前記第３の光路の中心軸線とを
平行にし、かつ前記第１の光路の中心軸線と前記第３の
光路の中心軸線とを一致させ、しかも前記平行光の光路
と前記第３の光路とを前記ビームスプリッタをはさんで
相対させる構成にし、さらに前記第３の光路におけるレ
ーザ光をビームスプリッタと独立に配置した集光レンズ
により集光光とし、この集光光の一部をナイフエッジプ
リズムで反射してトラッキング信号検出受光素子に入射
させ、かつ前記ナイフエッジプリズムで反射されない集
光光をフォーカス信号検出受光素子に入射させたもので
ある。Means for Solving the Problems The optical pickup apparatus of the present invention in order to achieve the above object, an optical pickup device used for an optical information recording and reproducing apparatus, a cup laser light morphism emitted from the laser diode into parallel light by the ring lens, the parallel light by the beam splitter
The reflected light is reflected / transmitted by the beam splitter.
The first light path, which is a reflected light path, is transmitted through
The laser light is split into a second optical path which is an optical path, the laser light in the split first optical path is made incident on a light receiving element for controlling a laser diode light amount, and the laser light in the split second optical path is recorded by an objective lens. is focused on the medium, the laser light reflected by this recording medium is advanced in the opposite said second optical path, and the reflection / transmission splitting surface of the beam splitter
And the light is emitted to a third optical path, the central optical axis of the parallel light is made parallel to the central axis of the third optical path, and the central axis of the first optical path is made parallel to the third optical path. The central axis of the optical path is made coincident, and the optical path of the parallel light and the third optical path are configured to be opposed to each other with the beam splitter interposed therebetween. Further, the laser light in the third optical path is independent of the beam splitter. The condensed light is condensed by the arranged condensing lens, and a part of the condensed light is reflected by the knife edge prism to be incident on the tracking signal detection light receiving element, and the condensed light not reflected by the knife edge prism is detected by the focus signal The light is incident on the light receiving element.
【０００７】[0007]
【作用】したがって、本発明によれば、ビームスプリッ
タの環境変化によって生じる変位による光軸のズレを防
止することができ、かつビームスプリッタを挟んで平行
調整手段と検出系を相対させることができるので、環境
変化を受けにくい小型の光学系を構成することができ
る。また、ナイフエッジプリズムを用いることにより、
ビームスプリッタの集光レンズ変位への影響を取り除
き、かつ集光レンズとフォーカス検出受光素子の間に光
軸に影響を与える光学素子を配置しないようにすること
により、フォーカス検出誤差を小さくすることができ
る。Therefore, according to the present invention, the deviation of the optical axis due to the displacement caused by the environmental change of the beam splitter can be prevented, and the parallel adjustment means and the detection system can be opposed to each other with the beam splitter interposed therebetween. In addition, it is possible to configure a small optical system that is not easily affected by environmental changes. Also, by using a knife edge prism,
The focus detection error can be reduced by removing the influence of the beam splitter on the displacement of the condenser lens and by not placing an optical element that affects the optical axis between the condenser lens and the focus detection light receiving element. it can.
【０００８】[0008]
【実施例】図１は本発明の第１の実施例における光ピッ
クアップ装置の構成を示したものである。図１におい
て、１はレーザダイオード(以下、ＬＤと略す)、２は発
散光を平行光にするカップリングレンズ(以下、ＣＬと
略す)、３はビームスプリッタ(以下、ＢＳと略す)、４
は90°偏向させる偏向プリズム(以下、ＤＰと略す)、５
は対物レンズ(以下、ＯＬと略す)、７は集光レンズ(以
下、ＤＬと略す)、８はナイフエッジプリズム(以下、Ｋ
ＥＰと略す)、９はフォーカス信号を調整するフォーカ
ス信号調整光学素子(以下、ＦＯ−ＡＤＪＰと略す)、10
はフォーカス信号受信素子(以下、ＦＯ−ＰＤと略す)、
11はトラッキング信号を調整するトラッキング信号調整
光学素子(以下、ＴＲ−ＡＤＪＰと略す)、12はトラッキ
ング信号受光素子(以下、ＴＲ−ＰＤと略す)である。FIG. 1 shows the structure of an optical pickup device according to a first embodiment of the present invention. In FIG. 1, 1 is a laser diode (hereinafter abbreviated as LD), 2 is a coupling lens (hereinafter abbreviated as CL) that converts divergent light into parallel light, 3 is a beam splitter (hereinafter abbreviated as BS), 4
Is a deflecting prism (hereinafter abbreviated as DP) that deflects 90 °, 5
Is an objective lens (hereinafter abbreviated as OL), 7 is a condenser lens (hereinafter abbreviated as DL), 8 is a knife edge prism (hereinafter abbreviated as K).
A focus signal adjusting optical element (hereinafter abbreviated as FO-ADJP) 9 for adjusting a focus signal;
Is a focus signal receiving element (hereinafter abbreviated as FO-PD),
Reference numeral 11 denotes a tracking signal adjusting optical element (hereinafter, abbreviated as TR-ADJP) for adjusting a tracking signal, and reference numeral 12 denotes a tracking signal light receiving element (hereinafter, abbreviated as TR-PD).
【０００９】以下、図１を参照して用いて光ピックアッ
プの光路について説明する。The optical path of the optical pickup will be described below with reference to FIG.
【００１０】光ピックアップ光路は大別して３つに分け
られる。すなわち、１つは照明系光路（第２の光路）で
あり、ＬＤ１から出射した発散光は、ＣＬ２を通過して
平行光になりＢＳ３に入射し、ＢＳ３内で反射されて90
度偏向させられる。ＢＳ３内部で偏光面に入射して偏光
面を透過したレーザ光は、ＢＳ３を出射した後にＤＰ４
に入射し、かつＤＰ４で反射されて90度偏向されＯＬ５
に向かう。ＤＰ４は、記録媒体の面下方向の光学系厚み
が増加して装置全体の厚さが増すことを、レーザ光を90
度折り曲げることによって防止している。The optical path of the optical pickup is roughly divided into three. That is, one is an illumination system optical path (second optical path), and the divergent light emitted from LD1 passes through CL2, becomes parallel light, enters BS3, is reflected in BS3, and is reflected by BS3.
Deflected by degrees. The laser beam incident on the polarization plane inside the BS3 and transmitted through the polarization plane is output from the DP3 after exiting the BS3.
And is reflected by DP4, deflected by 90 degrees, and OL5
Head for. DP4 is a laser light source that increases the thickness of the optical system 90 in the downward direction of the recording medium to increase the thickness of the entire apparatus.
It is prevented by bending it.
【００１１】また、他の光路は検出系光路（第３の光
路）であり、ＯＬ５で集光したレーザ光は記録媒体記録
面に集光し、各種信号を含んだ一部のレーザ光が反射
し、再びＯＬ５に戻り、ＢＳ３まで照明系光路とほぼ同
一の光路を逆進する。同一の光路を逆進するのはＯＬ５
の特性で、ある程度の記録媒体の傾きやＯＬ５，ＤＰ４
の変位があっても影響しない。再びレーザ光はＢＳ３に
入射し前記偏光面で反射され後述する検出系へと向か
う。The other optical path is a detection optical path (third optical path). The laser light condensed by the OL 5 is condensed on the recording surface of the recording medium, and a part of the laser light including various signals is reflected. Then, the flow returns to OL5 again, and reversely travels along the same optical path as the illumination system optical path to BS3. It is OL5 that reverses the same optical path.
Of the recording medium and OL5, DP4
There is no effect even if there is displacement. The laser beam again enters BS3, is reflected by the polarization plane, and travels to a detection system described later.
【００１２】さらに、他の光路はＬＤ制御系光路（第１
の光路）であり、ＢＳ３内部の偏光面までは照明系光路
（第２の光路）と同一であり、照明系光路ではレーザ光
が、偏光面を透過したのに対し、ＬＤ制御系光路（第１
の光路）では偏光面で反射してＬＤ発光量制御用のＬＤ
−ＰＤ６に入射する。Further, another optical path is an LD control system optical path (first optical path).
Up to the polarization plane inside the BS 3 is the same as the illumination system optical path (second optical path). In the illumination system optical path, the laser light has transmitted through the polarization plane, whereas the LD control system optical path (second 1
In the optical path), the light is reflected by the polarization plane to control the LD light emission amount.
-It is incident on PD6.
【００１３】本実施例のように光ピックアップの光路は
一般的にＢＳ３に集中しており、ＢＳ３の変位は全ての
光路に影響を与え、ＢＳ３の光路配置により光ピックア
ップの大きさが決定される。前述したようにＯＬ５とＢ
Ｓ３の間では照明系の光路（第２の光路）と検出系の光
路（第３の光路）が同一であることから、それぞれの光
路においてＢＳ３内部で一回ずつ反射を行い、ＣＬ２か
らＢＳ３に入射するレーザ光とＢＳ３から検出系へ出射
するレーザ光との２つのレーザ光の中心光軸が平行とな
るように配置することにより、ＢＳ３が変位しても２つ
の光路（第２の光路と第３の光路）の影響が打ち消し合
い２つの光路の関係が変化しない結果が得られる。つま
り、ＣＬ２からのレーザ光の光軸が変化しなければ検出
系への光軸も変化しない。なお、反射を一回ずつとした
のは、前述したように記録媒体記録面の光スポット性能
劣化および信号劣化を抑えるためである。As in this embodiment, the optical path of the optical pickup is generally concentrated on the BS3, and the displacement of the BS3 affects all the optical paths, and the size of the optical pickup is determined by the arrangement of the optical paths of the BS3. . OL5 and B as described above
During S3, since the optical path (second optical path) of the illumination system and the optical path (third optical path) of the detection system are the same, reflection is performed once inside BS3 in each optical path, and the light is reflected from CL2 to BS3. By arranging the two laser beams, the incident laser beam and the laser beam emitted from the BS 3 to the detection system, to be parallel to each other, the two optical paths (the second optical path and the The effect of the third optical path cancels out, and the result that the relationship between the two optical paths does not change is obtained. That is, if the optical axis of the laser beam from CL2 does not change, the optical axis to the detection system does not change. The reason why the reflection is performed once is to suppress the deterioration of the light spot performance and the deterioration of the signal on the recording surface of the recording medium as described above.
【００１４】ＣＬ２からのレーザ光の一部は前述のよう
に第１の光路であるＬＤ制御系光路に偏向しなければな
らない。また、検出系光路では記録媒体からの反射光を
第３の光路である検出系へ偏向しなければならない。つ
まり、ＢＳ３は、第１の光路と第３の光路への光偏向機
能も必要となる。そこで、ＬＤ制御系光路（第１の光
路）の中心軸線と、検出系の光路（第３の光路）の中心
軸線とを一致させることにより、１つの反射面(偏光面)
で２つの光路の偏向が可能となる。偏光面の偏向特性
は、２つの光路（第１の光路と第３の光路）の必要特性
を満足する必要はあるが、ＬＤ制御系回路ゲインの最適
化により容易に得られる。A part of the laser light from CL2 must be deflected to the LD control system optical path, which is the first optical path, as described above. In the optical path of the detection system, the reflected light from the recording medium must be deflected to the third optical path, that is, the detection system. That is, the BS 3 also needs a function of deflecting light into the first optical path and the third optical path. Therefore, by making the central axis of the optical path of the LD control system (first optical path) coincide with the central axis of the optical path of the detection system (third optical path), one reflection surface (polarization surface) is obtained.
Thus, two optical paths can be deflected. The polarization characteristics of the polarization plane need to satisfy the required characteristics of the two optical paths (the first optical path and the third optical path), but can be easily obtained by optimizing the LD control system circuit gain.
【００１５】ＬＤ１およびＣＬ２は、平行光の平行度を
保ち、かつレーザ光の強度中心がＯＬ５の中心光軸と一
致するように、ＬＤ１はＸＹ方向、ＣＬ２はＸＹＺ方向
等に調整する平行光調整手段が必要である。LD1 and CL2 maintain parallelism of parallel light, and LD1 is adjusted in XY directions and CL2 is adjusted in XYZ directions so that the center of intensity of laser light coincides with the center optical axis of OL5. Means are needed.
【００１６】また、検出系はラジオ用波数(ＲＦ)信号
(再生信号として使用)、トラッキング信号およびフォー
カス信号を検出するための光学素子および調整手段が必
要である。このため、平行光調整手段と検出系は光ピッ
クアップに占める割合が大きい。それに対してＬＤ−Ｐ
Ｄ６は、光量制御のモニタを用いることから受光部に光
が入射しているだけでよく、十分大きい受光面積があれ
ば調整は不要であり、受光素子自体も前者２つに比べる
と十分小さい。The detection system is a radio wave number (RF) signal.
(Used as a reproduction signal), an optical element for detecting a tracking signal and a focus signal, and an adjusting means are required. Therefore, the parallel light adjusting means and the detection system occupy a large proportion in the optical pickup. LD-P
Since D6 uses a monitor for controlling the amount of light, it is only necessary that light is incident on the light receiving unit. If there is a sufficiently large light receiving area, no adjustment is necessary, and the light receiving element itself is sufficiently smaller than the former two.
【００１７】そこで、ＬＤ−ＰＤ６がＢＳ３を挟んで検
出系の反対側に位置することから、ＬＤ−ＰＤ６側に平
行光調整手段を配置することにより平行光調整手段の付
近に小さいＬＤ−ＰＤ６の配置を行った方が、平行光調
整手段と検出系を同方向に配置するよりも光ピックアッ
プの空間の有効利用を図ることができる。また、対物レ
ンズＯＬが装置本体のほぼ中心に位置することから、Ｏ
Ｌ５−ＢＳ３間における第２の光路の中心軸線に対称に
なるように光学系を配置した方が、装置全体の空間の有
効利用を図ることができる。Therefore, since the LD-PD 6 is located on the opposite side of the detection system with the BS 3 interposed therebetween, by arranging the parallel light adjusting means on the LD-PD 6 side, the small LD-PD 6 can be located near the parallel light adjusting means. The arrangement allows more effective use of the space of the optical pickup than disposing the parallel light adjusting means and the detection system in the same direction. Further, since the objective lens OL is located substantially at the center of the apparatus main body, O
By arranging the optical system so as to be symmetric with respect to the central axis of the second optical path between L5 and BS3, it is possible to effectively use the space of the entire apparatus.
【００１８】図１は検出系にナイフエッジ法を用いてい
る。ナイフエッジ法では、光軸のズレが発生したり、集
光レンズ(ＤＬ)の位置が変化した場合、フォーカス信号
検出に誤差が発生しやすい特徴を有している。そのため
一般にＢＳ３に接着されているＤＬ７をＢＳ３と分離配
置し、ＢＳ３の変位に伴うＤＬ７の変位を取り除くこと
により、ＤＬ７に起因するフォーカス検出の誤差を減少
することができる。また、ナイフエッジプリズム(ＫＥ
Ｐ)８で反射(遮光)したレーザ光を、プッシュプル法の
トラッキング信号検出に用い、またナイフエッジプリズ
ムで反射(遮光)されなかったレーザ光をフォーカス信号
検出に用いることにより、ＫＥＰ８の変位による光軸ズ
レの影響をフォーカス信号検出に与えないようにするこ
とができる。FIG. 1 uses the knife edge method for the detection system. The knife edge method has a feature that an error easily occurs in focus signal detection when a shift of an optical axis occurs or a position of a condenser lens (DL) changes. Therefore, generally, by disposing the DL 7 adhered to the BS 3 separately from the BS 3 and removing the displacement of the DL 7 accompanying the displacement of the BS 3, it is possible to reduce the focus detection error caused by the DL 7. In addition, a knife edge prism (KE
The laser beam reflected (shielded) by P) 8 is used for tracking signal detection by the push-pull method, and the laser beam not reflected (shielded) by the knife edge prism is used for focus signal detection, so that the displacement of KEP 8 The influence of the optical axis shift can be prevented from affecting the focus signal detection.
【００１９】図２は本発明の第２の実施例における光磁
気信号検出可能な光ピックアップ装置の構成を示すもの
であり、図１と同一の符号を付した部材は同じ部材であ
って説明を省略する。図２において、13は光磁気信号の
検出感度を高くする光学素子である1/2波長板(1/2λ)、
14はビームスプリッタ(ＢＳ)、15はモニタ受光素子(Ｍ
Ｏ−ＰＤ）である。FIG. 2 shows the structure of an optical pickup device capable of detecting a magneto-optical signal according to a second embodiment of the present invention. The members denoted by the same reference numerals as those in FIG. Omitted. In FIG. 2, a half-wave plate (1 / 2λ) 13 is an optical element for increasing the detection sensitivity of a magneto-optical signal,
14 is a beam splitter (BS), 15 is a monitor light receiving element (M
O-PD).
【００２０】第２の実施例では、ＫＥＰ８で反射(遮光)
した後に光磁気信号検出に必要な1/2λ13およびＢＳ14
等を追加配置したことにより、フォーカス信号検出の光
路中への光学部品の追加を避け、各追加光学部品の変位
による光軸ズレの影響をフォーカス信号検出に与えない
光磁気信号の検出を行うことができる。In the second embodiment, the light is reflected (shielded) by KEP8.
1 / 2λ13 and BS14 required for magneto-optical signal detection after
By adding additional components, etc., avoid the addition of optical components in the optical path of focus signal detection, and detect magneto-optical signals that do not affect the focus signal detection due to the displacement of each additional optical component. Can be.
【００２１】図３は本発明の第３の実施例における光磁
気信号検出可能な光ピックアップ装置の構成を示すもの
であり、図１および図２と同一の符号を付した部材は同
じ部材であって説明を省略する。図３において、16はウ
ォラストンプリズム(ＷＰ)である。FIG. 3 shows a configuration of an optical pickup device capable of detecting a magneto-optical signal according to a third embodiment of the present invention. Members denoted by the same reference numerals as those in FIGS. 1 and 2 are the same members. The description is omitted. In FIG. 3, reference numeral 16 denotes a Wollaston prism (WP).
【００２２】第３の実施例では、ＫＥＰ８で反射(遮光)
した後に光磁気信号検出に必要な1/2λ13およびＷＰ16
等を追加配置したことにより、フォーカス信号検出の光
路中への光学部品の追加を避け、各追加光学部品の変化
による光軸ズレの影響をフォーカス信号検出に与えない
光磁気信号の検出を行うことができる。In the third embodiment, the light is reflected (shielded) by KEP8.
Λ13 and WP16 required for magneto-optical signal detection after
By adding additional components, etc., avoid the addition of optical components in the optical path of focus signal detection, and detect magneto-optical signals that do not affect the focus signal detection due to the shift of the optical axis due to the change of each additional optical component. Can be.
【００２３】[0023]
【発明の効果】以上説明したように、本発明によれば以
下に記載するような効果が得られる。As described above, according to the present invention, the following effects can be obtained.
【００２４】(1）ビームスプリッタの環境変化によって
生じる変位による光軸のズレを防止し、かつビームスプ
リッタを挟んで平行光調整手段と検出系が相対している
ので、環境の変化の影響を受けにくい小型の光学系を構
成することができる。(1) The displacement of the optical axis due to the displacement caused by the change in the environment of the beam splitter is prevented, and the parallel light adjusting means and the detection system are opposed to each other with the beam splitter interposed therebetween. It is possible to configure a small optical system that is difficult.
【００２５】(2）ナイフエッジプリズム法の光ピックア
ップにより、ビームスプリッタの集光レンズ変化への影
響を取り除き、かつ集光レンズとフォーカス検出受光素
子の間に光軸に影響を与える光学素子を配置しないこと
により、フォーカス検出誤差を小さくすることができ
る。(2) The optical pickup using the knife-edge prism method removes the influence of the beam splitter on the change of the condenser lens and arranges an optical element between the condenser lens and the focus detection light-receiving element that affects the optical axis. By not doing so, the focus detection error can be reduced.
【００２６】(3）集光レンズとフォーカス検出受光素子
の間に光磁気信号検出のための光学素子を配置しないこ
とにより、光磁気信号の検出に起因するフォーカス検出
誤差増加を避けることができる。(3) By not arranging an optical element for detecting a magneto-optical signal between the condenser lens and the focus detecting light receiving element, it is possible to avoid an increase in a focus detection error caused by detecting the magneto-optical signal.
【図１】本発明の第１の実施例における光ピックアップ
装置の構成図である。FIG. 1 is a configuration diagram of an optical pickup device according to a first embodiment of the present invention.
【図２】本発明の第２の実施例における光ピックアップ
装置の構成図である。FIG. 2 is a configuration diagram of an optical pickup device according to a second embodiment of the present invention.
【図３】本発明の第３の実施例における光ピックアップ
装置の構成図である。FIG. 3 is a configuration diagram of an optical pickup device according to a third embodiment of the present invention.
１…レーザダイオード(ＬＤ)、 ２…カップリングレン
ズ(ＣＬ)、 ３，14…ビームスプリッタ(ＢＳ)、 ４…
偏向プリズム(ＤＰ)、 ５…対物レンズ(ＯＬ)、６…受
光素子(ＬＤ−ＰＤ)、 ７…集光レンズ(ＤＬ)、 ８…
ナイフエッジプリズム(ＫＥＰ)、 ９…フォーカス信号
調整光学素子(ＦＯ−ＡＤＪＰ)、 10…フォーカス信号
受光素子(ＦＯ−ＰＤ)、 11…トラッキング信号調整光
学素子(ＴＲ−ＡＤＪＰ)、 12…トラッキング信号受光
素子(ＴＲ−ＰＤ)、 13…1/2λ波長板(1/2λ)、 15…
モニタ受光素子(ＭＯ−ＰＤ)、 16…ウォラストンプリ
ズム(ＷＰ)。1 ... Laser diode (LD), 2 ... Coupling lens (CL), 3,14 ... Beam splitter (BS), 4 ...
Deflection prism (DP), 5: Objective lens (OL), 6: Light receiving element (LD-PD), 7: Condensing lens (DL), 8 ...
Knife edge prism (KEP), 9: Focus signal adjusting optical element (FO-ADJP), 10: Focus signal light receiving element (FO-PD), 11: Tracking signal adjusting optical element (TR-ADJP), 12: Tracking signal reception Element (TR-PD), 13 ... 1 / 2λ wave plate (1 / 2λ), 15 ...
Monitor light receiving element (MO-PD), 16 ... Wollaston prism (WP).
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) G11B 7/12 - 7/22 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) G11B 7/ 12-7/22
Claims (3)
ピックアップ装置であって、レーザダイオードから出射
するレーザ光をカップリングレンズにより平行光にし、
この平行光をビームスプリッタ内で反射させ、この反射
光をビームスプリッタの反射／透過分割面に入射させ
て、反射光路である第１の光路と透過光路である第２の
光路へ分割させ、分割された第１の光路におけるレーザ
光をレーザダイオード光量制御のために受光素子に入射
させ、分割された第２の光路におけるレーザ光を対物レ
ンズにより記録媒体に集光させ、この記録媒体にて反射
したレーザ光を前記第２の光路を逆に進ませ、かつビー
ムスプリッタの前記反射／透過分割面で反射させて第３
の光路に出射させる構成にし、さらに前記平行光の中心
光軸と前記第３の光路の中心軸線とを平行にし、かつ前
記第１の光路の中心軸線と前記第３の光路の中心軸線と
を一致させ、しかも前記平行光の光路と前記第３の光路
とを前記ビームスプリッタをはさんで相対させる構成に
し、さらに前記第３の光路におけるレーザ光をビームス
プリッタと独立に配置した集光レンズにより集光光と
し、この集光光の一部をナイフエッジプリズムで反射し
てトラッキング信号検出受光素子に入射させ、かつ前記
ナイフエッジプリズムで反射されない集光光をフォーカ
ス信号検出受光素子に入射させたことを特徴とする光ピ
ックアップ装置。1. A optical pickup device used for an optical information recording and reproducing apparatus, into parallel light by the coupling lens laser light morphism emitted from the laser diode,
This parallel light is reflected in the beam splitter ,
Light is incident on the reflection / transmission division surface of the beam splitter
A first optical path that is a reflected optical path and a second optical path that is a transmitted optical path.
Splitting the laser light into an optical path, making the laser light in the first split optical path incident on the light receiving element for controlling the laser diode light quantity, and condensing the laser light in the second split optical path onto a recording medium by an objective lens ; the laser light reflected by the recording medium of this is advanced in the opposite said second optical path, and is reflected by the reflective / transmissive splitting surface of the Bee <br/> beam splitter 3
And the central optical axis of the parallel light and the central axis of the third optical path are parallel to each other, and the central axis of the first optical path and the central axis of the third optical path are aligned. The light path of the parallel light and the third light path are configured to be opposed to each other with the beam splitter interposed therebetween, and the laser light in the third light path is further separated by a condenser lens arranged independently of the beam splitter. As a condensed light, a part of the condensed light was reflected by a knife edge prism and made incident on a tracking signal detection light receiving element, and a condensed light not reflected by the knife edge prism was made incident on a focus signal detection light receiving element. An optical pickup device, characterized in that:
レーザ光を、第２のビームスプリッタに入射し、さらに
この第２のビームスプリッタにより形成される２つの光
路に分割して偏向させ、分割された各レーザ光を、それ
ぞれの対応する信号検出受光素子に入射させ、少なくと
も片方の前記信号検出受光素子でトラッキング信号を検
出し、かつそれぞれの受光素子に入射する光量の比較を
行うことで再生信号検出を行うことを特徴とする請求項
１記載の光ピックアップ装置。2. The light reflected by the knife edge prism.
Laser light is incident on the second beam splitter, and
Two lights formed by the second beam splitter
And deflects the laser light,
Attach to each corresponding signal detection light receiving element, at least
The tracking signal is detected by one of the signal detection light-receiving elements.
And compare the amount of light incident on each light receiving element.
2. The optical pickup device according to claim 1 , wherein the reproduction signal is detected by performing the operation .
レーザ光を、ウォラストンプリズムに入射し、さらにこ
のウォラストンプリズムにより形成される２つの光路に
分割して偏向させ、分割された各レーザ光を、それぞれ
の対応する信号検出受光素子に入射させ、少なくとも片
方の前記信号検出受光素子でトラッキング信号を検出
し、かつそれぞれの受光素子に入射する光量の比較を行
うことで再生信号検出を行うことを特徴とする請求項１
記載の光ピックアップ装置。 The 3. A laser beam reflected by said knife edge prism, incident on the Wollaston prism, Furthermore, the child
The two optical paths formed by the Wollaston prism
Divided by deflecting the laser beams which are divided, to be incident on each of the corresponding signal detecting light-receiving element, and detects a tracking signal at least one of the signal detection light receiving element, and is incident on the respective light receiving elements quantity claim 1 by performing a comparison and performing reproduction signal detection
An optical pickup device as described in the above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04044720A JP3131798B2 (en) | 1992-03-02 | 1992-03-02 | Optical pickup device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04044720A JP3131798B2 (en) | 1992-03-02 | 1992-03-02 | Optical pickup device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05242518A JPH05242518A (en) | 1993-09-21 |
| JP3131798B2 true JP3131798B2 (en) | 2001-02-05 |
Family
ID=12699266
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04044720A Expired - Fee Related JP3131798B2 (en) | 1992-03-02 | 1992-03-02 | Optical pickup device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3131798B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6002803B1 (en) * | 2015-04-27 | 2016-10-05 | 株式会社カーブスジャパン | Voice guide output device and exercise support method using the device |
-
1992
- 1992-03-02 JP JP04044720A patent/JP3131798B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6002803B1 (en) * | 2015-04-27 | 2016-10-05 | 株式会社カーブスジャパン | Voice guide output device and exercise support method using the device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05242518A (en) | 1993-09-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5809000A (en) | Optical pickup system for reading optical disks of different thicknesses | |
| KR20000071779A (en) | Optical head apparatus | |
| JP3131798B2 (en) | Optical pickup device | |
| US20010040844A1 (en) | Tracking servo apparatus of optical information recording and reproducing apparatus | |
| JPH07326083A (en) | Optical information reproducing device | |
| US6507548B1 (en) | Optical pickup device | |
| US6396638B1 (en) | Optical pickup device capable of stable tracking | |
| JPH07182666A (en) | Light pickup system | |
| JP3167171B2 (en) | Light head | |
| JP3122346B2 (en) | Optical pickup device | |
| JPH0384737A (en) | Focus control method | |
| US5461224A (en) | Optical pick-up device having light splitting means and focus error and tracking error detection | |
| JPH0863778A (en) | Optical pickup | |
| JP2002092925A (en) | Optical pickup unit | |
| JP2812764B2 (en) | Optical head for optical disk device | |
| JPH04141846A (en) | Optical head | |
| JPH08329518A (en) | Optical pickup | |
| JP3114301B2 (en) | Optical pickup device | |
| JPH07220299A (en) | Optical pickup device | |
| JPH02158923A (en) | Optical pickup device | |
| JPH04286729A (en) | Focus detecting device | |
| JPH04222937A (en) | Optical pickup and laser beam output control method for optical pickup | |
| JPS6124038A (en) | Optical pickup | |
| JPS63298725A (en) | Split type optical pickup | |
| JPH05258386A (en) | Optical head |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20071124 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081124 Year of fee payment: 8 |
|
| LAPS | Cancellation because of no payment of annual fees |