JPS61189416U

JPS61189416U -

Info

Publication number: JPS61189416U
Application number: JP7487685U
Authority: JP
Priority date: 1985-05-20
Filing date: 1985-05-20
Publication date: 1986-11-26
Anticipated expiration: 2000-05-20
Also published as: JPH0519852Y2

Description

[Brief explanation of the drawing]

第１図は本考案の光学式ピツクアツプ装置の模
式的斜視図、第２図及び第３図はその他の実施例
の模式的斜視図、第４図はその受光素子の模式的
平面図、第５図は従来の光学式ピツクアツプ装置
の模式的平面図、第６図はその受光素子の模式的
平面図である。１……光源、２……位相型回折板、３……対物
レンズ、４……デイスク、５……受光素子、１１
……ウエツジプリズム、１２……平行平面板、５
１，５２……受光素子、５３，５４……分割線。 FIG. 1 is a schematic perspective view of the optical pickup device of the present invention, FIGS. 2 and 3 are schematic perspective views of other embodiments, FIG. 4 is a schematic plan view of the light receiving element, and FIG. The figure is a schematic plan view of a conventional optical pickup device, and FIG. 6 is a schematic plan view of its light receiving element. DESCRIPTION OF SYMBOLS 1... Light source, 2... Phase type diffraction plate, 3... Objective lens, 4... Disc, 5... Light receiving element, 11
... Wedge prism, 12 ... Parallel plane plate, 5
1, 52... Light receiving element, 53, 54... Division line.

Claims

[Claims for Utility Model Registration] (1) A light source, an objective lens that focuses incident light emitted from the light source and incident on the disk onto the disk, and at least one of the reflected light reflected by the disk. A light-receiving element is placed in the optical path of the incident light and reflected light, and the depth of the groove is set to approximately 1/2 of the wavelength of the light emitted by the light source. In an optical pickup device having a diffraction means for diffracting into ±1st order diffracted light at a predetermined diffraction angle, the diffraction means diffracts the +1st order diffracted light or the −1st order
At least one of the bundles of the second-order diffracted light is made to be substantially aberration-free light, and the substantially aberration-free first-order diffracted light is irradiated onto the disk through the objective lens, and the reflected light diffracted by the diffraction means is One first-order diffracted light is received by the light receiving element through an optical member that provides an optical change for generating a focus error signal, and the light receiving element is divided into at least two parts, and the light receiving element is divided into at least two parts. An optical pickup device characterized in that the direction of the dividing line is substantially parallel to the diffraction direction of the diffraction means, and a focus error signal is generated from the output of the divided light receiving element. (2) The optical pickup device according to claim 1, wherein the optical member is a wedge prism. (3) The optical pickup device according to claim 1, wherein the optical member is a parallel plane plate. (4) The optical pickup device according to claim 1, wherein the optical member is a cylindrical lens.