JPS6245297Y2 - - Google Patents
Info
- Publication number
- JPS6245297Y2 JPS6245297Y2 JP18561781U JP18561781U JPS6245297Y2 JP S6245297 Y2 JPS6245297 Y2 JP S6245297Y2 JP 18561781 U JP18561781 U JP 18561781U JP 18561781 U JP18561781 U JP 18561781U JP S6245297 Y2 JPS6245297 Y2 JP S6245297Y2
- Authority
- JP
- Japan
- Prior art keywords
- objective lens
- movable coil
- light source
- laser light
- motor
- 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
Links
- 230000003287 optical effect Effects 0.000 claims description 6
- 238000001514 detection method Methods 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
Landscapes
- Moving Of The Head For Recording And Reproducing By Optical Means (AREA)
- Optical Recording Or Reproduction (AREA)
- Manufacturing Optical Record Carriers (AREA)
Description
【考案の詳細な説明】
本考案はレーザ光源による情報信号記録装置の
自動焦点調整装置に関するものである。[Detailed Description of the Invention] The present invention relates to an automatic focus adjustment device for an information signal recording device using a laser light source.
従来の光学記録装置の自動焦点調整装置を第１
図に示す。第１図において、可動コイル１に備え
られた対物レンズ２を、情報信号記録時のガラス
記録原盤３の回転時における面振れ等による記録
面の上下変動に追従させるため、レーザ光源４か
ら原盤３への出射光５の反射光６をフオトデイテ
クター７により検出し、その検出信号に基づき対
物レンズ２と原盤３との相対距離が対物レンズ２
の焦点位置に一致するように可動コイル１の制御
駆動をフオーカスサーボ回路８により行なつてい
る。しかし乍ら対物レンズ２を備えた可動コイル
１を可動コイル１の制御領域内へ上方より下方に
駆動するために、可動コイル１に取り付けられた
駆動部９を手動で操作する必要がある。今この駆
動をモーターによる電磁駆動により前記可動コイ
ル１の制御駆動領域内へ自動的に下降させて行な
うためには、対物レンズ２と記録原盤３との相対
距離が対物レンズ２の焦点位置に一致したとき原
盤３からの反射光６をフイトデイテクター７によ
り検出することによつて可動駆動を止める必要が
ある。しかし乍らレーザ光源４が発振していない
とき、該作業等により対物レンズ２を備えた可動
コイル１をモーターにより下降させて対物レンズ
２と原盤３の距離が対物レンズ２の焦点位置に一
致してもフオトデイテクター７は反射光が存在し
ないために反射光を検出できない。従つて対物レ
ンズ２は下降を続け、原盤３に接触し、対物レン
ズ２や原盤３を破損に至らしめる。尚第１図にお
いて１０，１１は集光レンズ、１２は偏光ビーム
スプリツタ、１３はλ／４板、１４はダイクロツ
クミラー、１５は情報信号記録ビーム光である。 The automatic focus adjustment device of the conventional optical recording device is the first
As shown in the figure. In FIG. 1, in order to cause an objective lens 2 provided in a movable coil 1 to follow vertical fluctuations of the recording surface due to surface wobbling etc. during rotation of the glass recording master 3 during information signal recording, a laser light source 4 The reflected light 6 of the emitted light 5 is detected by the photodetector 7, and based on the detection signal, the relative distance between the objective lens 2 and the master 3 is determined by the objective lens 2.
The movable coil 1 is controlled and driven by a focus servo circuit 8 so as to coincide with the focal position. However, in order to drive the movable coil 1 equipped with the objective lens 2 from above to below into the control area of the movable coil 1, it is necessary to manually operate the drive unit 9 attached to the movable coil 1. Now, in order to perform this drive by automatically lowering the movable coil 1 into the control drive area by electromagnetic drive by a motor, the relative distance between the objective lens 2 and the recording master 3 must match the focal position of the objective lens 2. At this time, it is necessary to stop the movable drive by detecting the reflected light 6 from the master disk 3 with the light detector 7. However, when the laser light source 4 is not oscillating, the movable coil 1 equipped with the objective lens 2 is lowered by the motor during this work, and the distance between the objective lens 2 and the master 3 matches the focal position of the objective lens 2. However, the photodetector 7 cannot detect the reflected light because there is no reflected light. Therefore, the objective lens 2 continues to descend and comes into contact with the master disc 3, causing damage to the objective lens 2 and the master disc 3. In FIG. 1, 10 and 11 are condenser lenses, 12 is a polarizing beam splitter, 13 is a λ/4 plate, 14 is a dichroic mirror, and 15 is an information signal recording beam.
本考案は上記問題に対処すべく為されたもので
あり、レーザ光源よりの出射光の有無を検出し、
対物レンズを備えた可動コイルを昇降させるモー
ターを制御する手段を、レーザ光源から光学記録
原盤への入射光路に沿う少なくとも一箇所に設け
たことにより、対物レンズ及び記録原盤の破損を
防止するようにしたものである。以下本考案を実
施例を示す図面（第２図，第３図）に基づいて説
明する。尚図中前記第１図に示す従来例と同一部
分は同一符号を用いて示している。先ず第１実施
例を第２図に基づき説明する。偏光ビームスプリ
ツタ１２の入射面に偏波面が垂直なレーザ出射光
５は、偏光ビームスプリツタ１２によりその進路
が90度曲げられる。しかしこのとき偏光ビームス
プリツタ１２による僅かな漏れ光１６は偏光ビー
ムスプリツタ１２の背後に設けたフオトデイテク
ター１７により検出される。その信号はフオーカ
スサーボ回路８を介して可動コイル１に備え付け
られたモーター１８に送られてモーター１８を制
御する。モーター１８による可動コイル１の駆動
は、対物レンズ２と記録原盤３との距離が対物レ
ンズ２の焦点位置に達したことをフオトデイテク
ター７により検出し停止される。従つて記録原盤
３の回転時における面振れ等による記録面の上下
変動に対物レンズ２を追従させることができる。
ところでレーザ光源４からの出射光５が無ければ
フオトデイテクター１７は漏れ光１６を検出しな
いため、モーター１８は駆動しない。そのため、
可動コイル１の下降を不可能にし、対物レンズ２
や記録原盤３の破損事故を防止し得る。又記録原
盤３を回転させて情報信号記録中にレーザ光源４
に対する通電が停止されてレーザ光源４の発振が
止まつたり、レーザ光源４からの出射光が障害物
で遮られてレーザ光源４からの出射光５がフオト
デイテクター１７に検出されなくなると、可動コ
イル１の制御駆動は停止し、可動コイル１をモー
ター１８により上方へ電磁駆動し、対物レンズ２
や記録原盤３の破損事故を防ぐことができる。 The present invention was developed to address the above problem, and detects the presence or absence of light emitted from a laser light source.
By providing a means for controlling a motor that raises and lowers a movable coil equipped with an objective lens at at least one location along the optical path of incidence from the laser light source to the optical recording master, damage to the objective lens and the recording master can be prevented. This is what I did. The present invention will be explained below based on drawings (FIGS. 2 and 3) showing embodiments. In the figure, the same parts as those of the conventional example shown in FIG. 1 are indicated using the same reference numerals. First, a first embodiment will be explained based on FIG. 2. The path of the emitted laser light 5 whose plane of polarization is perpendicular to the plane of incidence of the polarized beam splitter 12 is bent by 90 degrees by the polarized beam splitter 12 . However, at this time, a slight amount of leakage light 16 from the polarizing beam splitter 12 is detected by a photodetector 17 provided behind the polarizing beam splitter 12. The signal is sent to the motor 18 attached to the moving coil 1 via the focus servo circuit 8 to control the motor 18. The driving of the movable coil 1 by the motor 18 is stopped when the photodetector 7 detects that the distance between the objective lens 2 and the recording master 3 has reached the focal position of the objective lens 2. Therefore, the objective lens 2 can follow vertical fluctuations of the recording surface due to surface wobbling or the like when the recording master 3 rotates.
By the way, if there is no emitted light 5 from the laser light source 4, the photodetector 17 will not detect the leaked light 16, so the motor 18 will not be driven. Therefore,
It is impossible to lower the movable coil 1, and the objective lens 2
This can prevent damage to the recording master 3. Also, the laser light source 4 is turned on while the recording master disk 3 is being rotated to record information signals.
When the energization is stopped and the oscillation of the laser light source 4 stops, or the emitted light from the laser light source 4 is blocked by an obstacle and the emitted light 5 from the laser light source 4 is no longer detected by the photodetector 17, the movable The control drive of the coil 1 is stopped, and the movable coil 1 is electromagnetically driven upward by the motor 18, and the objective lens 2
This also prevents damage to the recording master 3.
以上第１実施例について述べたが、第３図に示
すようにレーザ光源４からの出射光５を検出する
フオトデイテクター１９をダイクロツクミラー１
４の背後に設けることも可能で、これによりレー
ザ光源４からの出射光５をダイクロツクミラー１
４からの漏れ光２０として検出することができ、
第１実施例と同様の効果が得られる。 The first embodiment has been described above, but as shown in FIG.
It is also possible to provide it behind the dichroic mirror 1, thereby directing the emitted light 5 from the laser light source 4 to the dichroic mirror 1.
It can be detected as leakage light 20 from 4,
The same effects as in the first embodiment can be obtained.
本考案自動焦点調整装置は以上述べたように実
施し得るもので、レーザ光源からの出射光の有無
を検出し、対物レンズを備えた可動コイルを昇降
させるモーターを制御する手段を設けたことによ
り前述のように対物レンズや記録原盤の破損事故
を確実に防止し得るものである。 The automatic focus adjustment device of the present invention can be implemented as described above, and is provided with a means for detecting the presence or absence of emitted light from a laser light source and controlling a motor that raises and lowers a movable coil equipped with an objective lens. As mentioned above, it is possible to reliably prevent damage to the objective lens or recording master.
第１図は従来例を示す構成図、第２図及び第３
図は本考案の第１及び第２実施例を示す構成図で
ある。
１……可動コイル、２……対物レンズ、３……
ガラス記録原盤、４……レーザ光源、５……出射
光、７……フオトデイテクター、８……フオーカ
スサーボ回路、１２……偏光ビームスプリツタ、
１４……ダイクロツクミラー、１７……フオトデ
イテクター、１８……モーター、１９……フオト
デイテクター。
Figure 1 is a configuration diagram showing a conventional example, Figures 2 and 3
The figures are configuration diagrams showing first and second embodiments of the present invention. 1...Movable coil, 2...Objective lens, 3...
Glass recording master, 4... Laser light source, 5... Emitted light, 7... Photo detector, 8... Focus servo circuit, 12... Polarizing beam splitter,
14... dichroic mirror, 17... photo detector, 18... motor, 19... photo detector.
Claims (1)
対物レンズを備えた可動コイルと、前記光学記録
原盤と対物レンズの相対距離の焦点位置に対する
変化分を前記レーザ光源からのレーザを用いて検
出しその検出信号に基づき前記対物レンズを備え
た可動コイルを前記相対距離が焦点位置に一致す
るように制御する手段と、前記可動コイルを制御
領域内へ電磁駆動するモーターと、前記レーザ光
源から前記光学記録原盤への入射光路に沿う少な
くとも一箇所において設けられ前記レーザ光源よ
りの出射光の有無を検出し前記モーターを制御す
る手段とを備えた自動焦点調整装置。 A movable coil equipped with a laser beam and an objective lens arranged opposite to the optical recording master disk, and a change in the relative distance between the optical recording master disk and the objective lens with respect to the focal position are detected using a laser beam from the laser light source. means for controlling the movable coil provided with the objective lens so that the relative distance coincides with the focal position based on a detection signal; a motor for electromagnetically driving the movable coil into a control area; An automatic focus adjustment device comprising means for detecting the presence or absence of light emitted from the laser light source and controlling the motor, the means being provided at at least one location along the optical path of incidence on the master disc.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18561781U JPS5890536U (en) | 1981-12-11 | 1981-12-11 | automatic focus adjustment device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18561781U JPS5890536U (en) | 1981-12-11 | 1981-12-11 | automatic focus adjustment device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5890536U JPS5890536U (en) | 1983-06-18 |
| JPS6245297Y2 true JPS6245297Y2 (en) | 1987-12-03 |
Family
ID=29986831
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18561781U Granted JPS5890536U (en) | 1981-12-11 | 1981-12-11 | automatic focus adjustment device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5890536U (en) |
-
1981
- 1981-12-11 JP JP18561781U patent/JPS5890536U/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5890536U (en) | 1983-06-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5136559A (en) | Optical information recording and reproducing apparatus using tracking mirror | |
| US4684797A (en) | Optical system and method for reducing vibration of an objective lens in an optical head assembly of an optical read/write system | |
| JPS6245297Y2 (en) | ||
| US4825064A (en) | Apparatus for energizing a semiconductor laser array having a plurality of light beam emitting points | |
| US5488592A (en) | Optical pickup device for magneto-optical disc reproducing system | |
| JPH0435222U (en) | ||
| JPH0746428B2 (en) | Optical pickup | |
| US5268892A (en) | Cover member for covering an optical system of an optical head device including a dust filter mounted in an off set air flow opening | |
| JPH0479071B2 (en) | ||
| JPS6245301Y2 (en) | ||
| JPS632999Y2 (en) | ||
| JPS5822165Y2 (en) | optical device | |
| JPS6025033A (en) | Optical head | |
| JP2614245B2 (en) | Information recording device | |
| JPH0766554B2 (en) | Recorded information reader | |
| JPS6028034A (en) | Optical recording and reproducing device of information | |
| JPH0470700B2 (en) | ||
| JPH01155504A (en) | Controller for external magnetic field of magneto-optical disk device | |
| JPS63317931A (en) | Optical head | |
| JPH0423330B2 (en) | ||
| JPH02109240U (en) | ||
| JPH05159341A (en) | Optical pickup device | |
| JPS6055890B2 (en) | Optical information recording and reproducing device | |
| JPH0721864B2 (en) | Optical information recording device | |
| JPH058497B2 (en) |