JPS61105920U - - Google Patents
Info
- Publication number
- JPS61105920U JPS61105920U JP18941784U JP18941784U JPS61105920U JP S61105920 U JPS61105920 U JP S61105920U JP 18941784 U JP18941784 U JP 18941784U JP 18941784 U JP18941784 U JP 18941784U JP S61105920 U JPS61105920 U JP S61105920U
- Authority
- JP
- Japan
- Prior art keywords
- lens
- objective
- spot
- recording
- tracking
- 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
Links
- 230000003287 optical effect Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 1
Landscapes
- Optical Recording Or Reproduction (AREA)
- Optical Head (AREA)
Description
第１図はこの考案に係わる対物レンズの斜視図
、第２図は第１図の正面図、第３図は従来例を示
す概略平面図、第４図はトラツキング原理を示す
説明図、第５図は第３図の回折格子の拡大斜視図
である。
２０……対物レンズ、２１……メインスポツト
形成用曲率部、２２Ａ，２２Ｂ……サブスポツト
形成用曲率部、２４……メインスポツト、２５Ａ
，２５Ｂ……サブスポツト。
Fig. 1 is a perspective view of an objective lens according to this invention, Fig. 2 is a front view of Fig. 1, Fig. 3 is a schematic plan view showing a conventional example, Fig. 4 is an explanatory diagram showing the tracking principle, Fig. 5 The figure is an enlarged perspective view of the diffraction grating of FIG. 3. 20...Objective lens, 21...Curved part for forming main spot, 22A, 22B...Curved part for forming sub-spot, 24...Main spot, 25A
, 25B...Sub spot.
Claims (1)
レンズに入射して微小スポツトを形成し、記録媒
体上に情報を記録もしくは再生する光学式情報記
録再生装置において、 プラスチツク製の対物レンズ上に、トラツキン
グのための補助スポツトを形成させる曲率を有す
る部分を設け、１枚の対物レンズにより情報の記
録再生用のメインビームとトラツキングのための
補助スポツトを形成することを特徴とする対物レ
ンズ装置。[Claims for Utility Model Registration] In an optical information recording/reproducing device that records or reproduces information on a recording medium by entering a laser beam emitted from a laser light source into an objective lens to form a minute spot, a plastic objective is provided. An objective characterized in that a part having a curvature that forms an auxiliary spot for tracking is provided on the lens, and a single objective lens forms a main beam for recording and reproducing information and an auxiliary spot for tracking. lens device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18941784U JPS61105920U (en) | 1984-12-12 | 1984-12-12 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18941784U JPS61105920U (en) | 1984-12-12 | 1984-12-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61105920U true JPS61105920U (en) | 1986-07-05 |
Family
ID=30746868
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18941784U Pending JPS61105920U (en) | 1984-12-12 | 1984-12-12 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61105920U (en) |
-
1984
- 1984-12-12 JP JP18941784U patent/JPS61105920U/ja active Pending