JPS6085723U

JPS6085723U - Sensor device for optical spot position control

Info

Publication number: JPS6085723U
Application number: JP17833483U
Authority: JP
Inventors: 大門　正博; 渡辺　勢夫
Original assignee: 三菱電機株式会社
Priority date: 1983-11-18
Filing date: 1983-11-18
Publication date: 1985-06-13

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 the drawing]

第１図は従来の光スポツト位置制御を行うためのセンサ
光学系を示す図、第２図は第１図における光検知器と光
スポットの関係を示す図、第３図ａ、　ｂは第１図に示
した光学系のフォーカスセンサの特性を示す図、第４図
はフォーカスセンサ特性が改良された従来例を示す図、
第５図はこの考案の一実施例による光スポツト位置制御
用センサ装置の光学系を示す図、第６図は同上装置にお
ける光検知器と光スポットとの関係を示す図、第７図〜
第９図はこの考案の他の実施例を示す図である。１・・・光ディスク、５・・・回折格子、６・・・収束
レンズ、１３ａ〜１３ｃ・・・光検知器、１４・・・シ
リンドリカルレンズ、１５・・・シリンドリカル凹レン
ズ、１７．１８・・・差動増幅器。１１１１１１１　　　　　　　　　　　　　　　　　１
　　ゝ／Ｊ）ｃ８ａ８ｂFig. 1 is a diagram showing a conventional sensor optical system for controlling the position of a light spot, Fig. 2 is a diagram showing the relationship between the photodetector and the light spot in Fig. 1, and Figs. A diagram showing the characteristics of the focus sensor of the optical system shown in the figure, FIG. 4 is a diagram showing a conventional example with improved focus sensor characteristics,
FIG. 5 is a diagram showing an optical system of a sensor device for controlling the position of a light spot according to an embodiment of the invention, FIG. 6 is a diagram showing the relationship between a photodetector and a light spot in the same device, and FIGS.
FIG. 9 is a diagram showing another embodiment of this invention. DESCRIPTION OF SYMBOLS 1... Optical disk, 5... Diffraction grating, 6... Converging lens, 13a-13c... Photodetector, 14... Cylindrical lens, 15... Cylindrical concave lens, 17.18... Differential amplifier. 1111111 1
ゝ/J) c8a8b

Claims

[Scope of utility model registration request]

(1) In a device that performs optical recording and reproduction by irradiating a light beam from a light source along the guide groove onto an information recording carrier provided with a guide groove, the light emitted from the light source is divided into at least three beams. a diffraction grating that divides into bundles; a converging lens that converges the reflected light from the information recording carrier; and a convergent lens arranged to receive the convergent light from the converging lens, the direction in which the guide groove of the information recording carrier extends. a cylindrical lens that converges or diverges a luminous flux in a direction substantially perpendicular or parallel to the
Provided at an imaging position of one of the three beam bundles in a direction perpendicular to the direction in which the guide groove extends, and straddles at least two light receiving elements of a plurality of divided light receiving sections. a photodetector for detecting a bundle of light rays; a signal detection means for obtaining a focused point signal based on signals from the plurality of light receiving sections of the photodetector; A light source comprising: two photodetectors that detect respective light beams in correspondence with each other; and signal detection means for obtaining a track tracking signal from the signals of the two photodetectors. Sensor device for spot position control.

(2) The sensor device for controlling the position of a light spot according to claim 1, which is a utility model registration, characterized in that a concave lens is inserted between the converging lens and the photodetector.