公开(公告)号：US20120195180A1

公开(公告)日：2012-08-02

申请号：US13358842

申请日：2012-01-26

申请人： Yuki KOSHIMIZU ,  Mitsuru ITO ,  Hiroyuki ICHIKAWA

发明人： Yuki KOSHIMIZU ,  Mitsuru ITO ,  Hiroyuki ICHIKAWA

IPC分类号： G11B7/135

CPC分类号： G11B7/1362 ,  G11B7/135 ,  G11B7/1365 ,  G11B7/1378 ,  G11B7/13922 ,  G11B2007/0006

摘要： An optical-pickup apparatus includes: a single-wavelength-laser diode to emit a first-laser beam; a two-wavelength-laser diode to emit second- and third-laser beams; an objective lens; a photodetector to be irradiated with first- to third-reflected-light beams of the first- to third-laser beams reflected from the signal-recording layers of first- to third-optical discs; an aberration-correcting plate to guide the second- and third-laser beams toward the lens, and correct astigmatism of the reflected-light beams, and guide the astigmatism-corrected-reflected-light beams toward the photodetector; a semitransparent mirror to guide, toward the lens, the first-laser beam and the second- and third-laser beams having been guided by the aberration-correcting plate, and guide the reflected-light beams toward the aberration-correcting plate; a quarter-wave plate to convert the first- to third-laser beams from linearly-polarized light into circularly-polarized light, and convert the reflected-light beams from circularly-polarized light into linearly-polarized light; and a divergent lens to correct aberration caused by the mirror.

摘要翻译： 光拾取装置包括：发射第一激光束的单波长激光二极管; 用于发射第二和第三激光束的双波长激光二极管; 物镜; 照射从第一至第三光盘的信号记录层反射的第一至第三激光束的第一至第三反射光束的光电检测器; 用于将第二和第三激光束引向透镜的像差校正板，并且校正反射光束的像散，并将像散校正的反射光束引导到光电检测器; 将半导体镜引导到透镜，第一激光束以及由像差校正板引导的第二和第三激光束，并将反射光束引导到像差校正板; 将第一至第三激光束从线性偏振光转换成圆偏振光的四分之一波片，并将来自圆偏振光的反射光束转换成线偏振光; 以及用于校正由镜子引起的像差的发散透镜。

公开(公告)号：US08385182B2

公开(公告)日：2013-02-26

申请号：US13215787

申请日：2011-08-23

申请人： Yuki Koshimizu ,  Hiroyuki Ichikawa

发明人： Yuki Koshimizu ,  Hiroyuki Ichikawa

IPC分类号： G11B7/00

CPC分类号： G11B7/1365 ,  G11B7/1362 ,  G11B7/1376 ,  G11B7/13925 ,  G11B2007/0013

摘要： An optical-pickup apparatus includes: a laser diode; an objective lens; a diffraction grating; a photodetector including main-beam-, first-sub-beam-, and second-sub-beam-light-receiving portions; a quarter-wave plate having either a second area allowing a reflected-laser beam to pass therethrough without polarization or a third area allowing the reflected beam to pass therethrough at a polarization angle different from that of the first area; and a polarizing member having a separate-light-amount ratio set therefor with respect to the reflected beams passing through the second or third area and an area excluding the second or third area from the first area, such that proportions of the reflected beams passing therethrough toward the photodetector are different, thereby decreasing an irradiation level when the first- and second-sub-beam-light-receiving portions are irradiated, as stray light, with the reflected beam reflected from either one, not subjected to a signal-reading operation, of the first- and second-signal-recording layers of an optical disc.

摘要翻译： 一种光拾取装置，包括：激光二极管; 物镜; 衍射光栅; 光检测器，包括主光束，第一子光束和第二副光束光接收部分; 具有允许反射激光束通过而没有偏振的第二区域的四分之一波片或允许反射光束以不同于第一区域的偏振角通过的第三区域; 以及偏振构件，其相对于穿过第二或第三区域的反射光束和从第一区域排除第二或第三区域的区域设定的单独光量比，使得通过其的反射光束的比例 对于光电检测器是不同的，从而当第一和第二副光束受光部分被照射时作为杂散光而使从任何一个反射的反射光束不受信号读取操作的照射水平的降低 的光盘的第一和第二信号记录层。

公开(公告)号：US20120069724A1

公开(公告)日：2012-03-22

申请号：US13215787

申请日：2011-08-23

申请人： Yuki Koshimizu ,  Hiroyuki Ichikawa

发明人： Yuki Koshimizu ,  Hiroyuki Ichikawa

IPC分类号： G11B7/1353

CPC分类号： G11B7/1365 ,  G11B7/1362 ,  G11B7/1376 ,  G11B7/13925 ,  G11B2007/0013

摘要： An optical-pickup apparatus includes: a laser diode; an objective lens; a diffraction grating; a photodetector including main-beam-, first-sub-beam-, and second-sub-beam-light-receiving portions; a quarter-wave plate having either a second area allowing a reflected-laser beam to pass therethrough without polarization or a third area allowing the reflected beam to pass therethrough at a polarization angle different from that of the first area; and a polarizing member having a separate-light-amount ratio set therefor with respect to the reflected beams passing through the second or third area and an area excluding the second or third area from the first area, such that proportions of the reflected beams passing therethrough toward the photodetector are different, thereby decreasing an irradiation level when the first- and second-sub-beam-light-receiving portions are irradiated, as stray light, with the reflected beam reflected from either one, not subjected to a signal-reading operation, of the first- and second-signal-recording layers of an optical disc.

摘要翻译： 一种光拾取装置，包括：激光二极管; 物镜; 衍射光栅; 光检测器，包括主光束，第一子光束和第二副光束光接收部分; 具有允许反射激光束通过而没有偏振的第二区域的四分之一波片或允许反射光束以不同于第一区域的偏振角通过的第三区域; 以及偏振构件，其相对于穿过第二或第三区域的反射光束和从第一区域排除第二或第三区域的区域设定的单独光量比，使得通过其的反射光束的比例 对于光电检测器是不同的，从而当第一和第二副光束受光部分被照射时作为杂散光而使从任何一个反射的反射光束不受信号读取操作的照射水平的降低 的光盘的第一和第二信号记录层。