JPS645220U

JPS645220U -

Info

Publication number: JPS645220U
Application number: JP9887187U
Authority: JP
Priority date: 1987-06-27
Filing date: 1987-06-27
Publication date: 1989-01-12

Description

[Brief explanation of the drawing]

第１図は本考案に係るビームスポツト観測装置
の一例を示す概略構成図、第２図は第１図に示さ
れる例に用いられる検出カメラが備える撮像面部
及び円筒面型凹レンズの一例を示す概略構成図、
第３図、第４図、第５図及び第６図は第１図に示
される例の動作説明に供される波形図、第７図は
光学ピツクアツプを示す概略構成図である。図中、１は光学系ブロツク、２はレーザダイオ
ード、６は対物レンズ、９はフオーカス制御コイ
ル、２０は観測用対物レンズ、２１はビームスプ
リツタ、２４は観測カメラ、２８は第１の検出カ
メラ、２９は第２の検出カメラ、２８ａ及び２９
ａは撮像面部、４０及び４１は円筒面型凹レンズ
、４４はＣＣＤラインイメージセンサ、５１は観
測部、５２はフオーカス状態検出部である。 Fig. 1 is a schematic configuration diagram showing an example of a beam spot observation device according to the present invention, and Fig. 2 is a schematic diagram showing an example of an imaging surface section and a cylindrical concave lens included in a detection camera used in the example shown in Fig. 1. Diagram,
3, 4, 5, and 6 are waveform diagrams used to explain the operation of the example shown in FIG. 1, and FIG. 7 is a schematic configuration diagram showing an optical pickup. In the figure, 1 is an optical system block, 2 is a laser diode, 6 is an objective lens, 9 is a focus control coil, 20 is an observation objective lens, 21 is a beam splitter, 24 is an observation camera, and 28 is a first detection camera. , 29 are second detection cameras, 28a and 29
40 and 41 are cylindrical surface type concave lenses, 44 is a CCD line image sensor, 51 is an observation section, and 52 is a focus state detection section.

Claims

[Claims for Utility Model Registration] An optical pickup comprising a light beam generation source, an objective lens for converging the light beam from the light beam generation source, and a focus control means for the objective lens, which is opposed to the objective lens. a beam splitter that splits a light beam from the objective lens of the optical pickup that has passed through the observation objective lens into at least a first and a second split light beam; an observation section for observing the beam spot of the second divided light beam; and an imaging means having an imaging surface section formed by a plurality of line image sensors arranged in parallel and for imaging the beam spot of the second divided light beam. , the second above
optical means for flattening the divided light beam so that its cross-sectional shape has a longitudinal direction along the direction in which each of the plurality of line image sensors in the imaging means extends, and causing the split light beam to enter the imaging surface portion of the imaging means; and forming a detection output signal in accordance with a focus state for forming a beam spot of the first divided light beam in the observation section, based on the imaging output signal obtained from the imaging means. A light beam spot observation device comprising: a focus state detection section; and a focus control section that drives focus control means of the optical pickup according to a detection output signal obtained from the focus state detection section.