公开(公告)号：US20160086628A1

公开(公告)日：2016-03-24

申请号：US14890970

申请日：2013-05-22

Applicant: Hitachi, Ltd.

Inventor： Jiro HASHIZUME ,  Kazuyoshi YAMAZAKI ,  Seiichi KATOU ,  Katsuhiko KIMURA

IPC: G11B7/1353 ,  G02B26/08

CPC classification number: G11B7/1353 ,  G02B26/08 ,  G11B7/0065 ,  G11B7/083 ,  G11B7/08564 ,  G11B7/1381

Abstract: Diffracted light generated by a recording medium in reproduction is largely blocked by a spatial filter because of a position shift of the recording medium. Thus, the light amount of the diffracted light converged onto an optical detector is reduced and a satisfactory level of a reproducing signal cannot be obtained. In addition, in recording, it is necessary to fix the position of the spatial filter in rays for removing unnecessary frequency components or the like in a light beam emitted from a light source. In actuators having at least two spatial filters, one spatial filter is mounted on an actuator driven along two or more axes and moves independently of another spatial filter, and the other spatial filter is fixed to a common one-axis actuator. Switching of the positions of the spatial filters is performed by the common one-axis actuator.

Abstract translation: 由于记录介质的位置偏移，由再现中的记录介质产生的衍射光被空间滤波器大大阻挡。 因此，聚光到光学检测器上的衍射光的光量减少，并且不能获得满意的再现信号电平。 此外，在记录中，需要用光线固定空间滤波器的位置，以消除从光源发射的光束中不必要的频率分量等。 在具有至少两个空间滤波器的致动器中，一个空间滤波器安装在沿着两个或多个轴驱动的致动器上，并独立于另一个空间滤波器移动，另一个空间滤波器被固定到公共的单轴致动器。 空间滤波器的位置的切换由公共单轴致动器执行。