公开(公告)号：US06261707B1

公开(公告)日：2001-07-17

申请号：US08147373

申请日：1993-11-03

申请人： Yoshiteru Murakami ,  Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta ,  Naoyasu Iketani

发明人： Yoshiteru Murakami ,  Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta ,  Naoyasu Iketani

IPC分类号： G11B566

CPC分类号： G11B7/126 ,  G11B7/00718 ,  G11B11/10506 ,  G11B11/10515 ,  G11B11/10517 ,  G11B11/10543 ,  G11B11/10584 ,  G11B11/10586 ,  G11B11/10595 ,  Y10S428/90

摘要： A magneto-optical recording medium is composed of a base which has a property that a light can be transmitted therethrough, a readout layer formed on the base, which has in-plane magnetization at room temperature, whereas, a transition occurs from in-plane magnetization to perpendicular magnetization as the temperature thereof is raised and a recording layer formed on the readout layer for recording information magneto-optically. A recording and reproducing method and the optical head are designed for the magneto-optical recording medium. By the recording and reproducing method using the optical head, information recorded at high density can be reproduced.

摘要翻译： 磁光记录介质由具有光透射性的基底组成，形成在基底上的读出层，其在室温下具有面内磁化，而从平面内发生转变 随着其温度升高，磁化至垂直磁化，以及形成在读出层上用于磁光记录信息的记录层。 记录和再现方法和光学头被设计用于磁光记录介质。 通过使用光学头的记录和再现方法，可以再现以高密度记录的信息。

公开(公告)号：US5777953A

公开(公告)日：1998-07-07

申请号：US769254

申请日：1996-12-18

申请人： Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta

发明人： Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta

IPC分类号： G11B11/10 ,  G11B11/105 ,  G11B11/00

CPC分类号： G11B11/10515 ,  G11B11/10584 ,  G11B11/10589 ,  G11B11/10593

摘要： A magneto-optical recording medium is arranged so that (1) a first transparent dielectric layer, (2) a reproduction layer showing in-plane magnetization at room temperature while showing perpendicular magnetization in response to temperature rise, (3) a second transparent dielectric layer, (4) a recording layer made of perpendicular magnetization film; and (5) a protective layer are laminated on a substrate in this order. The reproduction layer has a thickness of 5 nm to 30 nm, the second transparent dielectric layer has a thickness of 6 nm to 40 nm, and the recording layer has a thickness of 20 nm to 80 nm. It is possible to separately reproduce individual recording bit even when one or more adjacent recording bits exist within the diameter of the light beam converged onto a target recording bit. This is because the information of a recording magnetic domain of a portion showing in-plane magnetization is masked.

摘要翻译： 磁光记录介质被布置成使得（1）第一透明介电层，（2）再现层，其在室温下显示面内磁化同时响应于温度升高而显示垂直磁化强度，（3）第二透明电介质 层，（4）由垂直磁化膜制成的记录层; 和（5）保护层依次层压在基板上。 再生层的厚度为5nm〜30nm，第二透明电介质层的厚度为6nm〜40nm，记录层的厚度为20nm〜80nm。 即使在收敛到目标记录位上的光束的直径内存在一个或多个相邻记录位，也可以分别再现单个记录位。 这是因为屏蔽显示面内磁化的部分的记录磁畴的信息。

公开(公告)号：US5707727A

公开(公告)日：1998-01-13

申请号：US395165

申请日：1995-02-27

申请人： Akira Takahashi ,  Yoshiteru Murakami ,  Junsaku Nakajima ,  Kenji Ohta ,  Junichiro Nakayama ,  Hiroyuki Katayama ,  Michinobu Mieda

发明人： Akira Takahashi ,  Yoshiteru Murakami ,  Junsaku Nakajima ,  Kenji Ohta ,  Junichiro Nakayama ,  Hiroyuki Katayama ,  Michinobu Mieda

IPC分类号： G11B11/10 ,  G11B11/105 ,  G11B5/66 ,  B32B5/16 ,  G11B5/02 ,  G11B11/00

CPC分类号： G11B11/10593 ,  G11B11/10506 ,  G11B11/10515 ,  G11B11/10517 ,  G11B11/10586 ,  Y10S428/90 ,  Y10T428/26 ,  Y10T428/265

摘要： A magneto-optical recording medium has a recording layer whereon information is magneto-optically recorded. A readout layer is provided on the recording layer. The readout layer has a compensating temperature that is located between room temperature and the Curie temperature. In the readout layer, upon an application of a light beam, the in-plane magnetization occurs at room temperature and a transition from the in-plane magnetization to vertical magnetization occurs as the temperature of the irradiated area of the readout layer rises above a predetermined temperature. By employing this magneto-optical recording medium, with an application of a light beam that is intensity modulated into two levels, only a spot having a temperature not less than a predetermined temperature is involved in the reproduction; therefore, a recorded bit with a size smaller than the diameter of the light beam can be reproduced, thereby greatly increasing the recording density. Further, the level of the reproduced signals is increased, and crosstalk from the adjoining tracks is reduced; thus, information recording and overwriting can be conducted more easily.

摘要翻译： 磁光记录介质具有磁信息记录信息的记录层。 读出层设置在记录层上。 读出层具有位于室温和居里温度之间的补偿温度。 在读出层中，在施加光束时，在室温下发生平面内磁化，并且随着读出层的照射区域的温度上升到预定值以上，从面内磁化向垂直磁化的转变发生 温度。 通过采用该磁光记录介质，通过施加强度调制为两个级别的光束，只有具有不低于预定温度的温度的点参与再现; 因此，可以再现具有小于光束直径的尺寸的记录位，从而大大提高记录密度。 此外，再现信号的电平增加，并且来自相邻轨道的串扰减小; 因此，可以更容易地进行信息记录和重写。

公开(公告)号：US5615182A

公开(公告)日：1997-03-25

申请号：US511283

申请日：1995-08-04

申请人： Yoshiteru Murakami ,  Junsaku Nakajima ,  Akira Takahashi ,  Junichiro Nakayama ,  Kenji Ohta

发明人： Yoshiteru Murakami ,  Junsaku Nakajima ,  Akira Takahashi ,  Junichiro Nakayama ,  Kenji Ohta

IPC分类号： G11B11/10 ,  G11B11/105 ,  G11B11/00

CPC分类号： G11B11/10515 ,  G11B11/10595

摘要： A magneto-optical disk, which possesses a disc-shaped substrate and a recording layer composed of a perpendicular magnetization film that is formed on the substrate, characterized in having: an area wherein magnetic domains having an upward magnetization and magnetic domains having a downward magnetization are alternately aligned along at least one circuit of the disk, the area being formed on the recording layer, the length of the magnetic domains having the upward magnetization being virtually equal to the length of the magnetic domains having the downward magnetization. This invention also has a reproducing method which is characterized in that, when information is reproduced by projecting a light beam onto the magneto-optical recording disk, the intensity of the light beam is adjusted so as to maximize the amplitude of a reproduced signal that is obtained from the area. With the above arrangement, a high-quality reproduced signal can be obtained independent of the characteristics of individual magneto-optical disks.

摘要翻译： 一种磁光盘，其具有盘形基板和由形成在基板上的垂直磁化膜构成的记录层，其特征在于具有：具有向上磁化的磁畴和具有向下磁化的磁畴的区域 沿着盘的至少一个电路交替排列，所述区域形成在记录层上，具有向上磁化的磁畴的长度实质上等于具有向下磁化的磁畴的长度。 本发明还具有一种再现方法，其特征在于，当通过将光束投射到磁光记录盘上来再现信息时，调整光束的强度，以使得再现信号的幅度最大化 从该地区获得。 通过上述配置，可以独立于各个磁光盘的特性来获得高质量的再生信号。

公开(公告)号：US06665235B2

公开(公告)日：2003-12-16

申请号：US10214881

申请日：2002-08-08

申请人： Yoshiteru Murakami ,  Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta ,  Naoyasu Iketani

发明人： Yoshiteru Murakami ,  Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta ,  Naoyasu Iketani

IPC分类号： G11B1100

CPC分类号： G11B11/10586 ,  B60T1/005 ,  F16D63/00 ,  G11B7/00718 ,  G11B7/126 ,  G11B11/10506 ,  G11B11/10515 ,  G11B11/10517 ,  G11B11/10543 ,  G11B11/10595

摘要： Featured is a recording and reproducing method of a magneto-optical recording medium including a recording layer for recording thereon information magneto-optically and a readout layer which has in-plane magnetization at room temperature and where a transition occurs from in-plane magnetization to perpendicular magnetization as temperature raises. The method includes projecting a light beam onto such a magneto-optical recording medium so as to form a perpendicularly magnetized area in the readout layer by duplication of the magnetization of said recording layer to the area. In further embodiments, the recording medium further includes an intermediate layer made of non-magnetic film formed between the readout and recording layers and the readout and recording layers are composed of rare-earth transition metal alloys such as TbFeCo (recoding layer) readout layer, made of GdFeCo (readout layer).

摘要翻译： 特别是磁光记录介质的记录和再现方法，其包括用于在其上记录磁光信息的记录层和在室温下具有面内磁化的读出层，并且其中从面内磁化转变为垂直 磁化随温度升高。 该方法包括将光束投影到这种磁光记录介质上，以便通过将所述记录层的磁化复制到该区域而在读出层中形成垂直磁化区域。 在另外的实施例中，记录介质还包括由读出和记录层之间形成的非磁性膜制成的中间层，并且读出和记录层由稀土过渡金属合金如TbFeCo（记录层）读出层， 由GdFeCo（读出层）制成。

公开(公告)号：US06483785B1

公开(公告)日：2002-11-19

申请号：US09685829

申请日：2000-10-10

申请人： Yoshiteru Murakami ,  Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta ,  Naoyasu Iketani

发明人： Yoshiteru Murakami ,  Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta ,  Naoyasu Iketani

IPC分类号： G11B1100

CPC分类号： G11B7/126 ,  G11B7/00718 ,  G11B11/10506 ,  G11B11/10515 ,  G11B11/10517 ,  G11B11/10543 ,  G11B11/10584 ,  G11B11/10586 ,  G11B11/10595 ,  Y10S428/90

摘要： Featured is a recording and reproducing method for recording and reproducing information on and from a recording medium. The medium includes a base having a property that a light can be transmitted therethrough, a readout layer formed on the base, which has an in-plane magnetization at room temperature, whereas, a transition occurs from in-plane magnetization to perpendicular magnetization as temperature rises and a recording layer formed on said readout layer for recording thereon information magneto-optically. A groove for guiding a light beam is formed on a readout layer side of the base and a groove width is set substantially equal to a land width formed between grooves. The recording layer on the grooves and the recording layer on lands are used in recording and reproducing information. Further a light beam is incident on a converging lens of an optical head, the light beam having a larger diameter &ohgr; than an aperture &agr; of the converging lens for converging the light beam on a predetermined position of the magneto-optical recording medium.

摘要翻译： 特色是用于在记录介质上记录和再现信息的记录和再现方法。 该介质包括具有光可以透射的性质的基底，形成在基底上的读出层，其在室温下具有面内磁化强度，而从平面内磁化转变为垂直磁化转变为温度 并且在所述读出层上形成用于在其上记录光学信息的记录层。 在基板的读出层侧形成用于引导光束的槽，并且将槽宽度设定为与槽之间形成的焊盘宽度大致相等。 凹槽上的记录层和焊盘上的记录层用于记录和再现信息。 此外，光束入射到光学头的会聚透镜上，所述光束具有比会聚透镜的孔径α更大的直径Ω，用于将光束会聚在磁光记录介质的预定位置。

公开(公告)号：US5595805A

公开(公告)日：1997-01-21

申请号：US318536

申请日：1994-10-05

申请人： Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta

发明人： Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi ,  Kenji Ohta

IPC分类号： G11B11/10 ,  G11B11/105 ,  G11B5/66

CPC分类号： G11B11/10515 ,  G11B11/10584 ,  G11B11/10586 ,  Y10S428/90

摘要： A magneto-optical medium has a substrate through which a light beam is transmitted and a recording-reproduction layer. The recording-reproduction layer, which exhibits an in-plane magnetization characteristic at the first temperature while still containing magnetization components in the perpendicular direction corresponding to information, comes to exhibit a perpendicular magnetization characteristic above the second temperature higher than the first temperature. In this magneto-optical recording medium, information is reproduced by utilizing a temperature distribution of the recording-reproduction layer being subjected to irradiation of a light beam and by raising the temperature of a portion within a light spot of the light beam from the first temperature to the second temperature.

摘要翻译： 磁光介质具有透射光束的基板和记录再生层。 在与信息对应的垂直方向上仍然含有磁化成分的情况下，在第一温度下表现出面内磁化特性的记录再现层在高于第一温度的第二温度以上呈现垂直磁化特性。 在该磁光记录介质中，通过利用经受光束照射的记录再生层的温度分布，并且通过将来自第一温度的光束的光斑内的部分的温度升高来再现信息 到第二个温度。

公开(公告)号：US5477528A

公开(公告)日：1995-12-19

申请号：US346586

申请日：1994-11-16

申请人： Yoshiteru Murakami ,  Junsaku Nakajima ,  Akira Takahashi ,  Junichiro Nakayama ,  Kenji Ohta

发明人： Yoshiteru Murakami ,  Junsaku Nakajima ,  Akira Takahashi ,  Junichiro Nakayama ,  Kenji Ohta

IPC分类号： G11B11/10 ,  G11B11/105 ,  G11B7/00

CPC分类号： G11B11/10515 ,  G11B11/10595

摘要： A magneto-optical disk, which possesses a disc-shaped substrate and a recording layer composed of a perpendicular magnetization film that is formed on the substrate, characterized in having: an area wherein magnetic domains having an upward magnetization and magnetic domains having a downward magnetization are alternately aligned along at least one circuit of the disk, the area being formed on the recording layer, the length of the magnetic domains having the upward magnetization being virtually equal to the length of the magnetic domains having the downward magnetization. This invention also has a reproducing method which is characterized in that, when information is reproduced by projecting a light beam onto the magneto-optical recording disk, the intensity of the light beam is adjusted so as to maximize the amplitude of a reproduced signal that is obtained from the area. With the above arrangement, a high-quality reproduced signal can be obtained independent of the characteristics of individual magneto-optical disks.

摘要翻译： 一种磁光盘，其具有盘形基板和由形成在基板上的垂直磁化膜构成的记录层，其特征在于具有：具有向上磁化的磁畴和具有向下磁化的磁畴的区域 沿着盘的至少一个电路交替排列，所述区域形成在记录层上，具有向上磁化的磁畴的长度实质上等于具有向下磁化的磁畴的长度。 本发明还具有一种再现方法，其特征在于，当通过将光束投射到磁光记录盘上来再现信息时，调整光束的强度，以使得再现信号的幅度最大化 从该地区获得。 通过上述配置，可以独立于各个磁光盘的特性来获得高质量的再生信号。

公开(公告)号：US6042954A

公开(公告)日：2000-03-28

申请号：US844270

申请日：1997-04-18

申请人： Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi

发明人： Junji Hirokane ,  Junichiro Nakayama ,  Junsaku Nakajima ,  Akira Takahashi

IPC分类号： G11B11/10 ,  G11B11/105 ,  G11B5/66

CPC分类号： G11B11/10586 ,  Y10S428/90

摘要： An magneto-optical recording medium includes: a transparent dielectric layer; a reproduction layer that is in an in-plane magnetization state at room temperature and changes into a perpendicular magnetization state with a rise in temperature; a non-magnetic intermediate layer; a recording layer made of a perpendicularly magnetized film; and a protection layer, the layers being formed one after another in this order. The recording layer is made of a rare-earth and transition metal alloy, and the rare earth metal is composed of more than two kinds of rare-earth-metal elements containing Gd. The information stored in a magnetic recording domain is masked with respect to a part that is in an in-plane magnetization state. Consequently, recording can be performed with a less powerful laser beam, and each recording bit can be reproduced independently to produce high quality signals even if the converged light beam covers a neighboring recording bit within its radius.

摘要翻译： 磁光记录介质包括：透明介质层; 在室温下处于面内磁化状态并随着温度升高而变成垂直磁化状态的再生层; 非磁性中间层; 由垂直磁化膜制成的记录层; 和保护层，这些层依次依次形成。 记录层由稀土和过渡金属合金制成，稀土金属由含有Gd的两种以上的稀土金属元素组成。 存储在磁记录领域中的信息相对于处于平面内磁化状态的部分被掩蔽。 因此，可以用较不强大的激光束执行记录，并且即使会聚光束覆盖其半径内的相邻记录位，也可以独立地再现每个记录位以产生高质量信号。

公开(公告)号：US5317555A

公开(公告)日：1994-05-31

申请号：US910837

申请日：1992-07-08

申请人： Akira Takahashi ,  Yoshiteru Murakami ,  Junsaku Nakajima ,  Kenji Ohta

发明人： Akira Takahashi ,  Yoshiteru Murakami ,  Junsaku Nakajima ,  Kenji Ohta

IPC分类号： G11B11/10 ,  G11B11/105 ,  G11B13/04

CPC分类号： G11B11/10545 ,  G11B11/10515

摘要： A magneto-optical disk has a recording layer whereon recorded bits are formed by the magnetic field modulation method and a readout layer whose axis of easy magnetization is parallel to the recording layer at room temperature, and varies to be perpendicular to the recording layer within a predetermined temperature range between room temperature and the Curie temperature. During reproduction of the recorded bits the first semiconductor laser emits a heating-use light beam to form the first light spot on the readout layer Thus, a ring-shaped region corresponding to the predetermined temperature range exhibits perpendicular magnetic anisotropy and the recorded bits are copied from the recording layer onto the ring-shaped region. As the first light spot is shifted, the ring-shaped region as a readout window of recorded bits is also shifted. Further, the second semiconductor laser emits a reproduction-use light beam such that the second light spot is formed on the readout layer to overlap the first light spot at a rear portion thereof. Consequently, only one recorded bit copied onto the rear portion of the ring-shaped region can be reproduced; therefore, high-quality reproduced signals can be obtained from the magneto-optical disk having information recorded with high density.

摘要翻译： 磁光盘具有通过磁场调制方法形成记录位的记录层和容易磁化的轴在室温下与记录层平行的读出层，并且在其内变化为垂直于记录层 室温和居里温度之间的预定温度范围。 在再现记录位期间，第一半导体激光器发出加热用光束，以在读出层上形成第一光点。因此，对应于预定温度范围的环形区域呈现垂直的磁各向异性，并且记录的位被复制 从记录层到环形区域。 当第一个光点移动时，作为记录位的读出窗口的环形区域也被移位。 此外，第二半导体激光器发射再现用光束，使得第二光点形成在读出层上，以在其后部与第一光点重叠。 因此，只能再现复制到环形区域后部的一个记录位; 因此，可以从具有以高密度记录的信息的磁光盘获得高质量的再现信号。