公开(公告)号：US07057994B2

公开(公告)日：2006-06-06

申请号：US10814192

申请日：2004-04-01

申请人： Hiromichi Ishibashi ,  Ken'ichi Kasazumi

发明人： Hiromichi Ishibashi ,  Ken'ichi Kasazumi

IPC分类号： G11B7/09

CPC分类号： G11B7/005 ,  G11B7/0053 ,  G11B2007/0006

摘要： When information is reproduced in an optical disk of high recording density or of low recording density, a main beam and sub-beams are emitted onto adjacent tracks. The main beam has a shape longer in a direction perpendicular to the tracks. When the optical disk of high recording density is reproduced, cross talk components from adjacent tracks included in signals reproduced from reflection light of the main beam are canceled by using signals reproduced from reflection lights of the sub-beams. When the optical disk of low recording density is reproduced, information is reproduced with a beam. Thus, two types of optical disks can be reproduced with a simple structure in a compatible way. In the cross talk canceling, discrimination marks formed along the tracks at constant distances are reproduced, and a time difference between the main beam and the sub-beams is corrected precisely by using track jump and detection of discrimination marks.

摘要翻译： 当在高记录密度或低记录密度的光盘中再现信息时，主光束和子光束被发射到相邻的光道上。 主梁具有在与轨道垂直的方向上更长的形状。 当再现高记录密度的光盘时，通过使用从副光束的反射光再现的信号来消除包含在主光束的反射光中再现的信号中的相邻光道的串扰分量。 当再现低记录密度的光盘时，用光束再现信息。 因此，可以以兼容的方式以简单的结构再现两种类型的光盘。 在串扰消除中，再现沿着轨道形成的识别标记，并且通过使用轨迹跳跃和识别标记的检测来精确地校正主光束和子光束之间的时间差。

公开(公告)号：US06650612B1

公开(公告)日：2003-11-18

申请号：US09536910

申请日：2000-03-28

申请人： Keiichi Matsuzaki ,  Teruhiro Shiono ,  Ken'ichi Kasazumi ,  Tetsuo Saimi

发明人： Keiichi Matsuzaki ,  Teruhiro Shiono ,  Ken'ichi Kasazumi ,  Tetsuo Saimi

IPC分类号： G11B700

CPC分类号： G11B7/1275 ,  G11B7/1353 ,  G11B7/1374 ,  G11B7/13922 ,  G11B2007/0006

摘要： An optical head according to the present invention includes: a first light source for emitting light with a first wavelength; a second light source for emitting light with a second wavelength longer than the first wavelength; and an objective lens for focusing the lights with the first and second wavelengths on information recording surfaces of information recording media corresponding to the lights with the respective wavelengths. The objective lens is designed so as to reduce aberration with respect to the light with the first wavelength. An optical-path length from the second light source to the objective lens is allowed to be shorter than that from the first light source to the objective lens so that aberration caused by the objective lens due to chromatic dispersion caused by a material of the objective lens is reduced with respect to the light with the second wavelength. Thus, using a common optical system, recording and/or reproduction can be carried out with respect to the respective information recording media corresponding to the first and second wavelengths. Furthermore, since the common optical system can be used, the optical head can be simplified in configuration and can be reduced in size.

摘要翻译： 根据本发明的光头包括：用于发射具有第一波长的光的第一光源; 第二光源，用于发射比第一波长长的第二波长的光; 以及用于将具有第一和第二波长的光聚焦在与具有相应波长的光对应的信息记录介质的信息记录表面上的物镜。 物镜被设计为减少相对于具有第一波长的光的像差。 允许从第二光源到物镜的光路长度短于从第一光源到物镜的光路长度，使得由物镜引起的色散引起的由于物镜引起的色差引起的像差 相对于具有第二波长的光而减小。 因此，使用普通的光学系统，可以相对于对应于第一和第二波长的各个信息记录介质执行记录和/或再现。 此外，由于可以使用普通的光学系统，所以可以简化光学头的结构并且可以减小尺寸。

公开(公告)号：US06292441B1

公开(公告)日：2001-09-18

申请号：US09061822

申请日：1998-04-16

申请人： Hiroaki Yamamoto ,  Daisuke Ogata ,  Ken'ichi Kasazumi ,  Seiji Nishino ,  Hidenori Wada ,  Sadao Mizuno

发明人： Hiroaki Yamamoto ,  Daisuke Ogata ,  Ken'ichi Kasazumi ,  Seiji Nishino ,  Hidenori Wada ,  Sadao Mizuno

IPC分类号： G11B700

CPC分类号： G11B7/131 ,  G11B7/0908 ,  G11B7/094 ,  G11B7/1353 ,  G11B7/1381

摘要： An optical head device includes a light source for emitting a light beam having a predetermined wavelength, an optical system for converging the light beam emitted from the light source on an information medium, and a light detector for receiving the light beam reflected from the information medium and detecting a focus error signal based on the received light beam. The light detector includes a plurality of pairs of photodetectors. The light detector generates the focus error signal based on a differential signal generated by each pair of the plurality of pairs of photodetectors. The plurality of pairs of photodetectors are arranged so that a fluctuation in the differential signal generated by at least one of the pairs of the plurality of pairs of photodetectors is cancelled by a fluctuation in the differential signal generated by at least another of the pairs of the plurality of pairs of photodetectors.

摘要翻译： 光头装置包括用于发射具有预定波长的光束的光源，用于将从光源发射的光束会聚在信息介质上的光学系统，以及用于接收从信息介质反射的光束的光检测器 以及基于所接收的光束检测聚焦误差信号。 光检测器包括多对光电检测器。 光检测器基于由每对多个光电检测器生成的差分信号产生聚焦误差信号。 多对光检测器被布置成使得由多对光检测器中的至少一对成对的光检测器产生的差分信号的波动被由至少另一对成对的光检测器产生的差分信号的波动所抵消 多对光电探测器。

公开(公告)号：US6111842A

公开(公告)日：2000-08-29

申请号：US15367

申请日：1998-01-29

申请人： Seiji Nishino ,  Hiroaki Yamamoto ,  Ken'ichi Kasazumi ,  Shin-ichi Kadowaki

发明人： Seiji Nishino ,  Hiroaki Yamamoto ,  Ken'ichi Kasazumi ,  Shin-ichi Kadowaki

IPC分类号： G11B7/13 ,  G11B7/09 ,  G11B7/125 ,  G11B7/135

CPC分类号： G11B7/1353 ,  G11B7/139 ,  G11B7/0901 ,  G11B7/0909

摘要： An optical head has a light source for emitting a light beam; optical device for condensing the emitted light beam onto an information recording medium and condensing light reflected from the information recording medium; and aperture limitation device for, of the condensed reflected light, causing light of a predetermined outer region to exit in a position different from a position where light of an inner region exits, wherein the light of the outer region and the light of the inner region caused to exit by the aperture limitation devices are separated to different places.

摘要翻译： 光头具有用于发射光束的光源; 光学装置，用于将发射的光束聚集到信息记录介质上并聚集从信息记录介质反射的光; 以及用于聚光反射光的孔径限制装置，使得预定外部区域的光在与内部区域的光的出射位置不同的位置处离开，其中外部区域的光和内部区域的光 导致由孔径限制装置退出分离到不同的地方。