JPS61175942A - Multi-optical head - Google Patents

Multi-optical head

Info

Publication number
JPS61175942A
JPS61175942A JP60014237A JP1423785A JPS61175942A JP S61175942 A JPS61175942 A JP S61175942A JP 60014237 A JP60014237 A JP 60014237A JP 1423785 A JP1423785 A JP 1423785A JP S61175942 A JPS61175942 A JP S61175942A
Authority
JP
Japan
Prior art keywords
light
wavelength
polarization
objective lens
reflected
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
JP60014237A
Other languages
Japanese (ja)
Inventor
Kimio Tateno
立野 公男
Yoshito Tsunoda
義人 角田
Akira Arimoto
昭 有本
Takeshi Maeda
武志 前田
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.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
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 Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP60014237A priority Critical patent/JPS61175942A/en
Publication of JPS61175942A publication Critical patent/JPS61175942A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To record and reproduce simultaneously plural pieces of tracks by using a laser arrays different in wavelength or polarization of each beam, and distributing each beam to each objective lens by an interference filter or a polarization filter. CONSTITUTION:A polarized beam splitter 2 is provided with an interference filter on the reflecting surface, and (s) polarization of a light of a wavelength lambda1 is reflected, goes to circularly polarized light through a wavelength plate 3a, stopped down by an objective lens 4a, and reaches on an optical disk 5. The beam which is reflected by the optical disk 5 passes through the wavelength plate 3a again, is made incident on a polarized light splitter 2a as (p) polariza tion, passes through it and reaches a photodetector 6a, and by the photodetector 6a, the reproducing signal of the optical disk, and a tracking signal and a focus ing signal for controlling a light spot are inputted. The light of a wavelength lambda2 passes through the polarized beam splitter 2a, is made incident on a polarized beam splitter 2b as S polarization, reflected by the reflecting surface provided with an interference filter, and can reproduce a signal of the second track which is stopped down by an objective lens 4b through a wavelength plate 3b in the same way as the case of lambda1. The light of lambda3 is also the same.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、光ディスクの記録再生用ピックアップに係り
、特に、該装置の高速化、高密度化、高精細化に好適な
マルチ光ヘッドに関する。
DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a pickup for recording and reproducing optical discs, and particularly to a multi-optical head suitable for increasing the speed, density, and definition of the device.

〔発明の背景〕[Background of the invention]

従来の光デイスク記録再生用ピックアップでは、1個の
光源に対し、1ケの対物レンズであり、レーザアレーを
光源とする場合でも、1ケの対物レンズに導くものしか
なかった。ところが、光ディスクの高速、高密度、高精
細化に向け、光ヘッドをマルチ化し、同時に数トラツク
を録再せねばならない問題が生じた。それは、単一光ヘ
ッドではディスクの回転速度が大きくなりすぎて、ディ
スクの破損等危険を伴うからマある。
In a conventional optical disk recording/reproducing pickup, there is one objective lens for one light source, and even when a laser array is used as the light source, there is only one objective lens to guide the light. However, in order to achieve higher speed, higher density, and higher definition of optical discs, a problem arose in which optical heads had to be multiplied and several tracks had to be recorded and played at the same time. This is because with a single optical head, the rotational speed of the disk becomes too high, leading to dangers such as damage to the disk.

〔発明の目的〕[Purpose of the invention]

本発明の目的は上述の欠点を克服し、同時に数トラツク
を録再することのできるマルチ光ヘッドを、レーザアレ
ーを用いることによりなそうとするものである。
SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned drawbacks and to create a multi-optical head capable of simultaneously recording and reproducing several tracks by using a laser array.

〔発明の概要〕[Summary of the invention]

本発明では、レーザアレーの各々の発振波長を異なるも
のとし、干渉フィルターを用いて分離し。
In the present invention, each laser array has a different oscillation wavelength and is separated using an interference filter.

各々の対物レンズへ、ビームを分配したことを特徴とす
るものである。これは、波長差でなく、偏光方向の違い
によっても分離することが可能である。
The feature is that the beam is distributed to each objective lens. This can be separated not only by a wavelength difference but also by a difference in polarization direction.

〔発明の実施例〕[Embodiments of the invention]

以下、本発明の一実施例を第1図により説明する。アレ
ーレーザ1が3つの発光点1a、lb。
An embodiment of the present invention will be described below with reference to FIG. The array laser 1 has three light emitting points 1a and lb.

1cからなる場合を考える。各発光点1a、lb。Consider a case consisting of 1c. Each light emitting point 1a, lb.

1cの発振波長をそれぞれλ1.λ2.λ、とする。偏
光ビームスプリッタ2は反射面に干渉フィルターが施し
てあり、波長λ□の光のS偏光は反射し、波長板3aを
経て円偏光となり、対物レンズ4aによって絞り込まれ
、光デイスク5上にいたる、光ディスク5によって反射
されたビームは、波長板3aを再び通過し、偏光スプリ
ッタ2aにp偏光として入射し、これを通過して光検知
器6aにいたる、光検知器6aにより、光ディスクの再
生信号、光点制御用のトラッキング信号とフォーカシン
グ信号をとり込むものとする。波長l□の光は偏光ビー
ムスプリッタ2aを通過し。
The oscillation wavelength of 1c is λ1. λ2. Let λ be. The polarizing beam splitter 2 has an interference filter on its reflective surface, and the S-polarized light of wavelength λ□ is reflected, passes through the wavelength plate 3a, becomes circularly polarized light, is focused by the objective lens 4a, and reaches the optical disk 5. The beam reflected by the optical disk 5 passes through the wave plate 3a again, enters the polarization splitter 2a as p-polarized light, passes through this, reaches the photodetector 6a, and is detected by the photodetector 6a as a reproduction signal of the optical disk, It is assumed that a tracking signal and a focusing signal for light point control are taken in. The light of wavelength l□ passes through the polarizing beam splitter 2a.

偏光ビームスプリッタ2bに8偏光として入射し、干渉
フィルターを施した反射面により反射され、λ1の場合
と同じように波長板3bを介して対物レンズ4bにより
絞り込まれ第2のトラックの信号を再生することができ
る。λ1の光についても同様である。
The light enters the polarizing beam splitter 2b as 8 polarized light, is reflected by the reflection surface provided with an interference filter, and is narrowed down by the objective lens 4b via the wavelength plate 3b as in the case of λ1 to reproduce the signal of the second track. be able to. The same applies to the light of λ1.

以上はλ1.λ3.λ、の三種の発振波長をもつアレー
レーザの場合であったが、三個以上の発光点を持つレー
ザについても同様に実施できることは云うまでもない。
Above is λ1. λ3. Although the present invention has been described in the case of an array laser having three oscillation wavelengths of λ, it goes without saying that the same method can be applied to a laser having three or more light emitting points.

次に本発明による第2の実施例について説明する。レー
ザ8は偏光ビームスプリッタ9に対し、p偏光となるよ
うに配置し、レーザ10は偏光ビームスプリッタ9に対
しS偏光となるように配置する。このようにすれば、二
つのレーザビームは偏光ビームスプリッタ9により一方
は透過、他方は反射し、一本に合成される0合成された
ビームは第2の偏光ビームスプリッタ11によった分離
され、それぞれ対物レンズ4a、4bに導かれたディス
ク上に絞り込まれ、同時に2つのトラックを録再できる
。ディスクからの反射光は波長板3a、3bにより偏光
方向が反転し、もとの位置に戻らず第3の偏光ビームス
プリッタ13に到達し、再び分離され、光検知器6a、
6bにより、それぞれ、信号再生が行なわれる。
Next, a second embodiment of the present invention will be described. The laser 8 is arranged to provide p-polarized light to the polarizing beam splitter 9, and the laser 10 is arranged to provide S-polarized light to the polarizing beam splitter 9. In this way, one of the two laser beams is transmitted by the polarizing beam splitter 9 and the other is reflected, and the combined beam is combined into one beam.The combined beam is separated by the second polarizing beam splitter 11. The light is focused onto the disk guided by objective lenses 4a and 4b, and two tracks can be recorded and played at the same time. The polarization direction of the reflected light from the disk is reversed by the wave plates 3a and 3b, and without returning to the original position, it reaches the third polarization beam splitter 13, where it is separated again and sent to the photodetector 6a,
6b performs signal reproduction, respectively.

〔発明の効果〕〔Effect of the invention〕

次に本発明の効果について述べる。すなわち、これまで
シングルビームにより、光デイスク上のただ1つのトラ
ックしか再生又は記録できなかったが1本発明により、
複数ビームを同一の光ヘッドから生成することが可能と
なり、同時に複数本のトラックを再生記録することが可
能となる。
Next, the effects of the present invention will be described. That is, until now only one track on an optical disk could be reproduced or recorded using a single beam, but with the present invention,
It becomes possible to generate a plurality of beams from the same optical head, and it becomes possible to simultaneously read and record a plurality of tracks.

これにより、光ディスクの回転数を増加することなく、
光ディスクの記録、再生密度を増大することが可能とな
り、また、ビット転送レートを増大し、より高速な光デ
ィスクの録再が可能となる。
As a result, without increasing the rotational speed of the optical disc,
It becomes possible to increase the recording and reproducing density of the optical disc, and also increases the bit transfer rate, making it possible to record and reproduce faster on the optical disc.

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

第1図は本発明によるマルチ光ヘッドの一実施例を示す
側面図、第2図は、本発明の別の実施例を示すマルチ光
ヘッドの側面図である。 1・・・アレーレーザ、2・・・偏光ビームスプリッタ
、3・・・波長板、4・・・対物レンズ、5・・・光デ
ィスク、6・・・光検知器、8・・・レーザ、9・・・
偏光ビームスプリッタ、10・・・レーザ、11・・・
偏光ビームスブリ¥1の 茎Z口
FIG. 1 is a side view showing one embodiment of a multi-optical head according to the present invention, and FIG. 2 is a side view of a multi-optical head showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Array laser, 2... Polarizing beam splitter, 3... Wave plate, 4... Objective lens, 5... Optical disk, 6... Photodetector, 8... Laser, 9...・・・
Polarizing beam splitter, 10...Laser, 11...
Polarized beam subli ¥1 stem Z mouth

Claims (1)

【特許請求の範囲】[Claims] 複数個の発光点を有するレーザアレーを光源とするマル
チ光ヘッドにおいて、各ビームの波長、あるいは偏光が
異なるレーザアレーを用い、各々のビームを干渉フィル
ターあるいは偏光フィルターにより各々の対物レンズに
分配したことを特徴とするマルチ光ヘッド。
A multi-optical head whose light source is a laser array with multiple light-emitting points is characterized by using a laser array in which each beam has a different wavelength or polarization, and each beam is distributed to each objective lens by an interference filter or a polarizing filter. Multi-optical head.
JP60014237A 1985-01-30 1985-01-30 Multi-optical head Pending JPS61175942A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP60014237A JPS61175942A (en) 1985-01-30 1985-01-30 Multi-optical head

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP60014237A JPS61175942A (en) 1985-01-30 1985-01-30 Multi-optical head

Publications (1)

Publication Number Publication Date
JPS61175942A true JPS61175942A (en) 1986-08-07

Family

ID=11855471

Family Applications (1)

Application Number Title Priority Date Filing Date
JP60014237A Pending JPS61175942A (en) 1985-01-30 1985-01-30 Multi-optical head

Country Status (1)

Country Link
JP (1) JPS61175942A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63112832A (en) * 1986-10-28 1988-05-17 Hitachi Ltd Optical head
EP0547853A2 (en) * 1991-12-19 1993-06-23 Xerox Corporation A raster output scanner for a multistation xerographic printing system
US6466535B2 (en) * 1997-11-01 2002-10-15 Samsung Electronics Co., Ltd. Method and apparatus for recording and reproducing data on and from an optical disk

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63112832A (en) * 1986-10-28 1988-05-17 Hitachi Ltd Optical head
EP0547853A2 (en) * 1991-12-19 1993-06-23 Xerox Corporation A raster output scanner for a multistation xerographic printing system
US6466535B2 (en) * 1997-11-01 2002-10-15 Samsung Electronics Co., Ltd. Method and apparatus for recording and reproducing data on and from an optical disk

Similar Documents

Publication Publication Date Title
KR100213282B1 (en) Optical pickup for a multi-layered disk
JPH1055566A (en) Optical pickup device
JP2950500B2 (en) Optical pickup for recording and reproduction for compatibility of discs with different thickness
JPH10199018A (en) Optical pickup device
KR0134276B1 (en) Optical pick up
KR100213270B1 (en) Optical pickup for use with a double-sided disk
US6125091A (en) Optical pickup apparatus for use with various types of optical disks
JPH02244445A (en) Optical information recording medium and optical information recording and reproducing device
JPS61175942A (en) Multi-optical head
JPH0714242A (en) Double-beam optical head
JPS59215033A (en) Optical disc recording and reproducing device
JPH03263637A (en) Method for recording and reproducing magneto-optical disk and magneto-optical disk device
JPH02192044A (en) Multi-beam separating device
JP2001176106A (en) Pickup device and information recording/reproducing device having its pickup device
JPS59142758A (en) Optical head for optical memory
JPH0391125A (en) Optical pickup device using wavelength multiplex recording system
KR0171080B1 (en) A recording and reproducing optical pickup system for the optical disk with plural recording layer in one side by generating successively different wavelength laser beam
KR0171077B1 (en) A recording and reproducing optical pickup system for optical disk with plural recording layer in one side by generating successively different polarization beam
JPH08338904A (en) Optical element and optical information recording and reproducing device
JP2935554B2 (en) Light head
KR0171079B1 (en) A recording and reproducing optical pickup system for the optical disk with plural recording layer in one side by generating successively different wavelength laser beam
JPS62164232A (en) Optical recording and reproducing device
JPS5897141A (en) Recorder and reproducer for optical information
JPH01144245A (en) Optical head
JPH08339551A (en) Optical information recording and reproducing device