公开(公告)号：US20080267042A1

公开(公告)日：2008-10-30

申请号：US12108908

申请日：2008-04-24

申请人： Yasuyuki KANO ,  Satomi Osugi ,  Tetsuhisa Hosokawa

发明人： Yasuyuki KANO ,  Satomi Osugi ,  Tetsuhisa Hosokawa

IPC分类号： G11B7/135

CPC分类号： G11B7/1365 ,  G11B7/1356 ,  G11B7/1374 ,  G11B2007/0006

摘要： A quarter-wave plate and a polarization beam splitter are used as means for guiding a laser beam to first and second objective lenses. A half of the circularly-polarized laser beam incident to the polarization beam splitter is reflected in the form of an S-polarized light component by the polarization beam splitter and guided to a first objective lens, and the other half is transmitted through the polarization beam splitter in the form of a P-polarized light component and guided to a second objective lens. The whole of light quantity of the laser beam reflected from an optical disk through the first or second objective lens passes substantially through the polarization beam splitter. Therefore, the light quantity of the laser beam guided to a photodetector can be enhanced.

摘要翻译： 四分之一波片和偏振分束器用作将激光束引导到第一和第二物镜的装置。 入射到偏振分束器的圆偏振激光束的一半被偏振分束器以S偏振光分量的形式反射并被引导到第一物镜，另一半透射通过偏振束 分离器以P偏振光分量的形式被引导到第二物镜。 从光盘通过第一或第二物镜反射的激光束的整个光量基本上通过偏振分束器。 因此，可以提高引导到光电检测器的激光束的光量。