JPS60169722U

JPS60169722U - Optical information reproducing device

Info

Publication number: JPS60169722U
Application number: JP4167285U
Authority: JP
Inventors: 近藤　光重; 健治朗木目
Original assignee: 三菱電機株式会社
Priority date: 1985-03-22
Filing date: 1985-03-22
Publication date: 1985-11-11

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

第１図は本考案の一実施例を示す概略構成図、第２図、
第３図は本考案による焦点ずれ検出の原理を説明する原
理図、第４図は偏向ミラーの回動による反射光の光路の
変化を示す説明図、第５図は第４図に示す場合に焦点ず
れ検出の誤差を避ける方法を示す構成図、第６図は本考
案に用いる光検知装置の他の例を示す斜視図、第７図は
本考案の他の実施例を示す部分構成図である。図において、１は光源、２は拡散レンズ、３はハーフミ
ラ−１４は偏向ミラー、５は集光レンズ、６は記録担体
、７は担体回転用モータ、８はハーフミラ−１１０は反
射光束、１１は焦点すれ信号、１２はレンズ移動装置、
１３．１４は反射光束、２１．２４は光検知器、２２．
２３は光検知装置、３１は差動増幅器、４１は短冊状不
透明物質、４２．４３は補正器、５０，５１，５２゜５
３はビームスポットである。なお、図中同一符号は同一
または相当部分を示す。ど″ □−−人一一一）＼　　φ　　　　　第６図Fig. 1 is a schematic configuration diagram showing an embodiment of the present invention; Fig. 2;
Fig. 3 is a principle diagram explaining the principle of defocus detection according to the present invention, Fig. 4 is an explanatory diagram showing changes in the optical path of reflected light due to rotation of the deflection mirror, and Fig. 5 is a diagram explaining the principle of defocus detection according to the present invention. FIG. 6 is a perspective view showing another example of the photodetecting device used in the present invention, and FIG. 7 is a partial configuration diagram showing another embodiment of the present invention. be. In the figure, 1 is a light source, 2 is a diffusing lens, 3 is a half mirror, 14 is a deflection mirror, 5 is a condensing lens, 6 is a recording carrier, 7 is a motor for rotating the carrier, 8 is a half mirror, 110 is a reflected light beam, and 11 is a reflected light beam. out-of-focus signal; 12 is a lens moving device;
13.14 is a reflected light beam, 21.24 is a photodetector, 22.
23 is a photodetector, 31 is a differential amplifier, 41 is a strip-shaped opaque material, 42.43 is a corrector, 50, 51, 52゜5
3 is a beam spot. Note that the same reference numerals in the figures indicate the same or corresponding parts. d″ □−−人一１一）＼ φ Figure 6

Claims

[Scope of utility model registration request]

A light source and a rotatable deflection mirror arranged on the optical axis substantially the same as the optical axis of the light emitted from the light source and condensing the light from the light source incident on the light source. a light condensing device that projects information onto an optical record carrier on which information is recorded and condenses a reflected light beam from the record carrier; a moving device that moves the light condensing device in the optical axis direction of the light condensing device; A beam separation device that separates the reflected light beam emitted from the light condensing device and deflected by the deflection mirror into two light beams; Disposed behind the condensing point, the longitudinal direction thereof is parallel to the moving direction of the optical path of the reflected light beam due to rotation of the deflection mirror, includes the center of the reflected light beam, and has a width narrower than the incident width of the reflected light beam. a pair of photodetectors each having a light-receiving surface provided with a rectangular dead area; and a control device added to the moving device so that the focal length is set to .