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：US5825723A

公开(公告)日：1998-10-20

申请号：US685534

申请日：1996-07-24

申请人： Junji Hirokane ,  Junichiro Nakayama ,  Akira Takahashi

发明人： Junji Hirokane ,  Junichiro Nakayama ,  Akira Takahashi

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

CPC分类号： G11B11/10586

摘要： A non-magnetic intermediate layer for intercepting magnetic exchange interaction is provided between a recording layer and a reproducing layer which are composed of a magnetic thin film with perpendicular magnetization. At this time, the reproducing layer is formed so that when an external magnetic field is applied thereto in reproducing information, its magnetization direction is arranged in the direction of the external magnetic field in a first temperature range, and when a light beam for reproduction is projected thereto and the reproducing layer is in a second temperature, the magnetization direction is arranged in the direction of a leakage magnetic flux generated from the recording layer, and is again arranged in the direction of the external magnetic field in a third temperature range. As a result, a rise and a fall of a reproducing signal detected from the reproducing layer can be made sharp, thereby achieving recording and reproducing at high density.

摘要翻译： 在由具有垂直磁化的磁性薄膜组成的记录层和再现层之间提供用于截取磁交换相互作用的非磁性中间层。 此时，再现层形成为当再现信息中施加外部磁场时，其磁化方向在第一温度范围内沿外部磁场的方向排列，并且当用于再现的光束为 投影到其上并且再现层处于第二温度，磁化方向被布置在从记录层产生的泄漏磁通的方向上，并且在第三温度范围内再次设置在外部磁场的方向上。 结果，可以使从再现层检测到的再现信号的上升和下降变得尖锐，从而实现高密度的记录和再现。

公开(公告)号：US5768218A

公开(公告)日：1998-06-16

申请号：US803274

申请日：1997-02-20

申请人： Junichiro Nakayama ,  Yoshiteru Murakami ,  Junji Hirokane ,  Akira Takahashi

发明人： Junichiro Nakayama ,  Yoshiteru Murakami ,  Junji Hirokane ,  Akira Takahashi

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

CPC分类号： G11B11/10584 ,  G11B11/10586 ,  G11B11/10506 ,  G11B11/10515 ,  G11B11/10521

摘要： A magneto-optical recording medium has a transparent substrate, a first magnetic layer, first intermediate layer, a second magnetic layer, and a third magnetic layer provided in this order. The first magnetic layer has an in-plane magnetization at room temperature, while a transition from the in-plane magnetization to a perpendicular magnetization occurs to the first magnetic layer with a temperature rise. The first intermediate layer is made of a non-magnetic substance. The second magnetic layer is a film having a perpendicular magnetization. The third magnetic layer is a film having a perpendicular magnetization, has a coercive force smaller than that of the second magnetic layer at room temperature, and has a Curie temperature higher than that of the second magnetic layer. The light intensity modulation overwriting method is applicable to the magneto-optical recording medium thus arranged, superior reproduction signal characteristics can be obtained with respect to this magneto-optical recording medium, and reproduction can be carried out with respect to the recording medium even though it has recording bits whose each diameter is smaller than that of a light beam. Thus it is possible to provide the magneto-optical recording medium suitable for high density recording.

摘要翻译： 磁光记录介质具有依次设置的透明基板，第一磁性层，第一中间层，第二磁性层和第三磁性层。 第一磁性层在室温下具有平面内的磁化强度，而从第一磁性层的温度上升发生从面内磁化向垂直磁化的转变。 第一中间层由非磁性物质制成。 第二磁性层是具有垂直磁化强度的膜。 第三磁性层是具有垂直磁化的膜，在室温下的矫顽力小于第二磁性层的矫顽力，并且居里温度高于第二磁性层的居里温度。 光强度调制重写方法适用于如此布置的磁光记录介质，可以获得相对于该磁光记录介质的优良再现信号特性，并且可以相对于记录介质进行再现，即使它 具有每个直径小于光束直径的记录位。 因此，可以提供适合于高密度记录的磁光记录介质。

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：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：US5939187A

公开(公告)日：1999-08-17

申请号：US859614

申请日：1997-05-20

申请人： Junji Hirokane ,  Junichiro Nakayama ,  Akira Takahashi

发明人： Junji Hirokane ,  Junichiro Nakayama ,  Akira Takahashi

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

CPC分类号： G11B11/10586 ,  Y10S428/90 ,  Y10T428/26 ,  Y10T428/265

摘要： A magneto-optical recording medium includes a reproducing layer which has in-plane magnetization at room temperature and has perpendicular magnetization at an elevated temperature of not less than a critical temperature, a recording layer made of a perpendicular magnetization film for recording information, an intermediate layer made of a non-magnetic film formed between the reproducing layer and the recording layer, and an in-plane magnetization layer adjacent to the reproducing layer, in which magnetization is reduced at a temperature in a vicinity of the critical temperature. According to the described magneto-optical recording medium, since information recorded in a recording magnetic domain of a portion having the in-plane magnetization is masked, even in the case where adjacent recording bits fall within a diameter of a spot of a converged light beam, each recording bit can be reproduced separately, thereby obtaining a quality reproduced signal.

摘要翻译： 磁光记录介质包括在室温下具有面内磁化并且在不低于临界温度的升高的温度下具有垂直磁化的再现层，由用于记录信息的垂直磁化膜制成的记录层，中间层 由形成在再现层和记录层之间的非磁性膜制成的层以及与再现层相邻的面内磁化层，其中磁化在临界温度附近的温度下降低。 根据所述的磁光记录介质，由于记录在具有面内磁化的部分的记录磁畴中的信息被掩蔽，所以即使在相邻记录位落入会聚光束的光点的直径的情况下 ，可以分别再现每个记录位，从而获得质量再现信号。

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：US5422865A

公开(公告)日：1995-06-06

申请号：US163355

申请日：1993-12-07

申请人： Hiroyuki Katayama ,  Junji Hirokane ,  Junichiro Nakayama ,  Akira Takahashi ,  Kenji Ohta

发明人： Hiroyuki Katayama ,  Junji Hirokane ,  Junichiro Nakayama ,  Akira Takahashi ,  Kenji Ohta

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

CPC分类号： G11B11/10506 ,  G11B11/10521

摘要： A magneto-optical recording method includes the steps of applying an external magnetic field perpendicularly onto the magnetic thin film with perpendicular magnetization of a magneto-optical recording medium and projecting a light beam onto the magneto-optical recording medium; and modulating the intensity of the light beam between the first light intensity and the second light intensity in response to the information to be recorded while shifting a spot of the light beam, thereby recording information. In the above method, the first light intensity is set such that by reducing the coercive force of the magnetic thin film with perpendicular magnetization, a magnetic domain is formed on the magnetic thin film with perpendicular magnetization, and that the magnetic domain is moved as the spot of the light beam is shifted. The second light intensity is set such that by increasing the coercive force of the magnetic thin film with perpendicular magnetization, the magnetic domain is fixed to the position.

摘要翻译： 磁光记录方法包括以下步骤：利用磁光记录介质的垂直磁化将磁场垂直地施加到磁性薄膜上并将光束投射到磁光记录介质上; 以及响应于要移动光束的点而要记录的信息，调制第一光强度和第二光强度之间的光束的强度，从而记录信息。 在上述方法中，第一光强度被设定为通过以垂直磁化强度降低磁性薄膜的矫顽力，在磁性薄膜上以垂直磁化形成磁畴，并且磁畴作为 光束的光斑被移动。 第二光强度被设定为通过以垂直磁化强度增加磁性薄膜的矫顽力，将磁畴固定在该位置上。

公开(公告)号：US06707766B2

公开(公告)日：2004-03-16

申请号：US10099968

申请日：2002-03-19

申请人： Go Mori ,  Naoyasu Iketani ,  Michinobu Mieda ,  Akira Takahashi

发明人： Go Mori ,  Naoyasu Iketani ,  Michinobu Mieda ,  Akira Takahashi

IPC分类号： G11B1100

CPC分类号： G11B11/10593 ,  G11B11/10584

摘要： A magneto-optical storage medium includes an interference layer, a magnetic domain expansion layer, an intermediate layer, a magnetic masking layer, a recording layer, and a protection layer which are sequentially formed on a substrate. The magnetic domain expansion layer produces a smaller frictional force due to wall coercivity than do the other magnetic layers. The intermediate layer has the Curie temperature TC2 which is lower than those of the other magnetic layers. The magnetic masking layer is in a perpendicular magnetization state at temperatures that are in a proximity of TC2, and changes into an in-plane magnetization state at temperatures that are higher than the proximity of TC2. The recording layer produces a higher coercive force than those produced by the magnetic domain expansion layer at room temperature.

摘要翻译： 磁光存储介质包括依次形成在基板上的干涉层，磁畴扩展层，中间层，磁屏蔽层，记录层和保护层。 与其它磁性层相比，磁畴扩展层由于壁矫顽力而产生较小的摩擦力。 中间层的居里温度TC2低于其他磁性层的居里温度TC2。 磁屏蔽层在接近TC2的温度下处于垂直磁化状态，并且在高于TC2的接近度的温度下变为面内磁化状态。 记录层产生比在室温下由磁畴扩展层产生的矫顽力更高的矫顽力。

公开(公告)号：US06338911B1

公开(公告)日：2002-01-15

申请号：US09429082

申请日：1999-10-29

申请人： Go Mori ,  Naoyasu Iketani ,  Michinobu Mieda ,  Akira Takahashi

发明人： Go Mori ,  Naoyasu Iketani ,  Michinobu Mieda ,  Akira Takahashi

IPC分类号： G11B566

CPC分类号： G11B11/10515 ,  G11B11/10584 ,  G11B11/10593 ,  Y10S428/90

摘要： A reproduction layer, a magnetic domain extending layer, an intermediate layer, and a recording layer are formed in this order. The magnetic domain extending layer, the intermediate layer, and the recording layer are exchange-coupled. The intermediate layer has a Curie temperature lower than that of any other magnetic layer. A non-magnetic intermediate layer is formed between the reproduction layer and the magnetic domain extending layer. Upon reproduction, magnetization information in the recording layer is transferred to and extended in the magnetic domain extending layer, where an extended magnetic domain is formed. The reproduction layer is magnetostatically coupled with the magnetic domain extending layer, so that the extended magnetic domain is transferred to the reproduction layer. This makes it possible to provide a magneto-optical recording medium characterized in moving of magnetic domain walls and extension of magnetic domains in good conditions, and increased signal intensity with a simpler structure.

摘要翻译： 依次形成再生层，磁畴延伸层，中间层和记录层。 磁畴延伸层，中间层和记录层是交换耦合的。 中间层的居里温度低于任何其他磁性层的居里温度。 在再现层和磁畴延伸层之间形成非磁性中间层。 在再现时，记录层中的磁化信息被转移到扩展磁畴的磁畴延伸层中并扩展。 再现层与磁畴延伸层磁静电耦合，从而将扩展磁畴转移到再现层。 这使得可以提供一种磁光记录介质，其特征在于在良好的条件下磁畴壁的移动和磁畴的延伸，并且以更简单的结构增加信号强度。