公开(公告)号：US5657299A

公开(公告)日：1997-08-12

申请号：US588629

申请日：1996-01-19

申请人： Junsaku Nakajima ,  Yoshiteru Murakami ,  Akira Takahashi

发明人： Junsaku Nakajima ,  Yoshiteru Murakami ,  Akira Takahashi

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

CPC分类号： G11B11/10593

摘要： A magneto-optical recording medium has magnetic multi-layers including a reproductive layer, which is a magnetic layer having perpendicular magnetic anisotropy, for reading out magneto-optically recorded information and a recording layer, which is a magnetic layer having perpendicular magnetic anisotropy, for magneto-optically recording information. In the magneto-optical recording medium, the following conditions are fulfilled:H.sub.C1 (ta)+.sigma.w(ta)/2M.sub.S1 (ta)h.sub.1

摘要翻译： 磁光记录介质具有磁性多层，包括作为具有垂直磁各向异性的磁性层的复制层，用于读出磁光记录的信息，以及作为具有垂直磁各向异性的磁性层的记录层，用于 磁光记录信息。 在磁光记录介质中满足以下条件：HC1（ta）+ sigma w（ta）/ 2MS1（ta）h1 <-HC1（t）+ sigmaw（t）/ 2MS1（t）h1， 40（nm）其中h1是生殖层的厚度，HC1（ta）是室温下的生殖层的矫顽力（ta），MS1（ta）是饱和磁化强度 的生物层MS2（ta）是记录层的饱和磁化强度，σw（ta）是在所述生殖层和记录层之间形成的磁畴壁的磁畴壁能量，HC1（t）是矫顽力 温度（t）不高于室温的一定温度（tm）的生殖层MS1（t）是生殖层的饱和磁化强度，MS2（t）是记录层的饱和磁化强度， 和σw（t）是在生殖层和记录层之间形成的磁畴壁的磁畴壁能。

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：US5989705A

公开(公告)日：1999-11-23

申请号：US748892

申请日：1996-11-14

申请人： Junsaku Nakajima ,  Yoshiteru Murakami ,  Akira Takahashi ,  Junji Hirokane

发明人： Junsaku Nakajima ,  Yoshiteru Murakami ,  Akira Takahashi ,  Junji Hirokane

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

CPC分类号： G11B11/10593 ,  Y10S428/90 ,  Y10T428/26 ,  Y10T428/265

摘要： A magneto-optical recording disk includes a recording layer for recording information as a mark and a reproduction layer, laminated with the recording layer, to which magnetization direction of the recording layer is transferred at high temperatures, wherein the reproduction layer and the recording layer are magnetostatically coupled and are not exchange-coupled. The information is read out by using a temperature distribution generated by a light beam for reproduction. The recording layer has, on a side thereof to which the reproduction layer is not provided, a supplementary back layer of a soft magnetic material composed of ferromagnetic material. The magneto-optical disk is designed to generate good CNR and thereby improves recording density even when a short mark is reproduced.

摘要翻译： 磁光记录盘包括用于记录作为标记的信息的记录层和与记录层层叠的记录层，记录层的高度方向在高温下被转印，其中再现层和记录层是 磁静态耦合并且不交换耦合。 通过使用由光束产生的温度分布来再现信息来读出信息。 记录层在其不具有再现层的一侧具有由铁磁材料构成的软磁性材料的补充背层。 磁光盘被设计成产生良好的CNR，从而即使在再现短标记时也提高记录密度。

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：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。

公开(公告)号：US5305300A

公开(公告)日：1994-04-19

申请号：US888548

申请日：1992-05-22

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

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

IPC分类号： G11B11/105 ,  G11B7/24

CPC分类号： G11B11/10582 ,  G11B11/10593 ,  Y10S428/90

摘要： A magneto-optical storage device having a configuration wherein a first AlN film, a Pt/co multi-layer film formed by alternately depositing Pt and Co, a second AlN film, and an Al reflective film are successively laminated on a substrate in this order. Assuming that respectively the thickness of the first AlN film is .delta.AlN (1); that of the second AlN film is .delta.AlN (2); that of the Pt single layer is .delta.Pt; that of the Co single layer is .delta.Co; and the total thickness of the Pt/Co multi-layer film is .delta.Pt/Co, each thickness of those layers is set to range within: 50 nm .ltoreq..delta.AlN (1).ltoreq.200 nm; 120 nm.ltoreq..delta.AlN (2).ltoreq.140 nm; 0.6 nm.ltoreq..delta.Pt.ltoreq.1.0 nm; 0.3 nm.ltoreq..delta.Co.ltoreq.0.6 nm; and 15 nm.ltoreq..delta.Pt/Co.ltoreq.20 nm. In accordance with the above arrangement, it is possible to greatly widen the tolerances of the film thicknesses of the first and second dielectric layers for obtaining a predetermined reflective index as well as a maximum Kerr rotation angle. Consequently, without strictly controlling the film thicknesses of the first and second AlN films, a magneto-optical storage device with stable performance suitable for practical use can be produced easily.

摘要翻译： 具有这样一种结构的磁光存储装置，其中第一AlN膜，通过交替沉积Pt和Co形成的Pt / co多层膜，第二AlN膜和Al反射膜依次层叠在基板上 。 假设第一AlN膜的厚度分别为（Δ）AlN（1）; 第二AlN膜的厚度为（Δ）AlN（2）; Pt单层为（delta）Pt; Co单层为（delta）Co; 并且Pt / Co多层膜的总厚度为（delta）Pt / Co，这些层的每个厚度设定在：50nm <=（delta）AlN（1）<= 200nm的范围内; 120nm <=（delta）AlN（2）<= 140nm; 0.6nm <=（delta）Pt <= 1.0nm; 0.3nm <=（delta）Co <= 0.6nm; 和15nm <=（delta）Pt / Co <= 20nm。 根据上述结构，可以大大拓宽第一和第二介质层的膜厚的公差，以获得预定的反射率以及最大的克尔旋转角。 因此，在不严格控制第一和第二AlN膜的膜厚的情况下，可以容易地制造出具有适合于实际应用的稳定性能的磁光存储装置。

公开(公告)号：US5637394A

公开(公告)日：1997-06-10

申请号：US356857

申请日：1994-12-15

申请人： Junsaku Nakajima ,  Naoyasu Iketani ,  Yoshiteru Murakami ,  Akira Takahashi ,  Hiroyuki Katayama ,  Kenji Ohta

发明人： Junsaku Nakajima ,  Naoyasu Iketani ,  Yoshiteru Murakami ,  Akira Takahashi ,  Hiroyuki Katayama ,  Kenji Ohta

IPC分类号： G11B11/105 ,  G11B5/66

CPC分类号： G11B11/10586 ,  G11B11/10515 ,  G11B11/10584 ,  Y10S428/90 ,  Y10T428/26 ,  Y10T428/265

摘要： A magneto-optical recording medium comprising a readout layer and a recording layer has a relationship that an external magnetic field H1 is smaller than an external magnetic field H4, where the H1 is a minimum external magnetic field necessary to make a magnetization direction of the readout layer direct to the direction reverse to a magnetization direction of the recording layer substantially at the room temperature, and the H4 is a maximum external magnetic field necessary to make the magnetization direction of the readout layer direct to the direction same as the magnetization direction of the recording layer at an high temperature not lower than a predetermined temperature. Moreover, the magneto-optical disk is provided, between the readout layer and the recording layer, with an intermediate layer which inhibits an effective bias magnetic field from the recording layer to the readout layer at the room temperature. Since it is possible to reproduce only the information in the high-temperature area close to the center of the laser beam irradiated during reproducing, recording density is improved. Furthermore, since an initializing magnetic field at reproducing is not necessary and the reproducing magnetic field can be made smaller, the apparatus can be made smaller and the electric power consumption can be decreased.

摘要翻译： 包括读出层和记录层的磁光记录介质具有外部磁场H1小于外部磁场H4的关系，其中H1是使读出磁化方向发生所需的最小外部磁场 层直接与基本上在室温下的记录层的磁化方向相反的方向，并且H4是使读出层的磁化方向直到与磁化方向相同的方向所需的最大外部磁场 记录层在不低于预定温度的高温下进行。 此外，在读出层和记录层之间设置磁光盘，其中间层在室温下抑制从记录层到读出层的有效偏置磁场。 由于只能再现靠近在再现期间照射的激光束的中心的高温区域的信息，所以记录密度提高。 此外，由于不需要再现时的初始化磁场并且可以使再现磁场更小，所以可以使装置更小，并且可以降低电力消耗。

公开(公告)号：US5757734A

公开(公告)日：1998-05-26

申请号：US668429

申请日：1996-06-17

申请人： Junsaku Nakajima ,  Junji Hirokane ,  Yoshiteru Murakami ,  Akira Takahashi

发明人： Junsaku Nakajima ,  Junji Hirokane ,  Yoshiteru Murakami ,  Akira Takahashi

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

CPC分类号： G11B11/10586 ,  G11B11/10515

摘要： A magneto-optical recording medium is composed of a reproducing layer, a recording layer, and an initializing layer, which are laminated in this order. The reproducing layer is provided so that a light beam is projected thereon so as to reproduce information. The recording layer is provided so that information is recorded therein and the information is copied to the reproducing layer at a readout temperature. The initializing layer is provided so that the reproducing layer is initialized at room temperature. Non-magnetic layers are provided between the reproducing layer and the recording layer and between the recording layer and the initializing layer, respectively, so that such two layers are not exchange-coupled each other. The recording layer has a compensation temperature of room temperature, while the initializing layer has a compensation temperature of the readout temperature, which is achieved by temperature rise caused by the projection of the light beam. With such an arrangement, an external magnetic field for initializing the reproducing layer and an external magnetic field for reproduction-use can be omitted, thereby preventing a recording device from becoming large in size, as well as enhancing the recording density of the recording layer.

摘要翻译： 磁光记录介质由再现层，记录层和初始化层组成，按顺序层叠。 提供再现层，使得光束在其上投影以再现信息。 提供记录层，使得信息被记录在其中，并且在读出温度下将信息复制到再现层。 提供初始化层，使得再现层在室温下被初始化。 在再现层和记录层之间以及记录层和初始化层之间分别设置非磁性层，使得这两层不相互交换。 记录层具有室温的补偿温度，而初始化层具有通过由光束的投影引起的温度上升而实现的读出温度的补偿温度。 通过这样的布置，可以省略用于初始化再现层的外部磁场和用于再现用途的外部磁场，从而防止记录装置尺寸变大，以及提高记录层的记录密度。

公开(公告)号：US5656385A

公开(公告)日：1997-08-12

申请号：US88608

申请日：1993-07-07

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

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

IPC分类号： G11B11/10 ,  G03G5/16 ,  G11B5/00 ,  G11B5/02 ,  G11B5/64 ,  G11B5/65 ,  G11B5/66 ,  G11B5/74 ,  G11B11/105 ,  G11B13/04 ,  G11B19/02

CPC分类号： G03G5/16 ,  G11B11/10589 ,  G11B13/045 ,  G11B5/00 ,  G11B5/656 ,  G11B11/10504 ,  G11B11/10515 ,  G11B11/10532 ,  G11B19/02 ,  G11B2005/0002 ,  G11B2005/0021 ,  G11B5/74 ,  Y10S428/90

摘要： A magnetic recording medium having a recording layer made up of a ferrimagnetic material whose compensation temperature is included within room temperatures and an information recording-reproduction method using the magnetic recording medium. During recording, while a light beam is projected on the recording layer so as to raise the temperature of a recording portion, information is recorded by applying a signal magnetic field from a magnetic head. During reproduction, while a light beam is projected on a reproducing portion of the recording layer so as to raise the temperature thereof, information is reproduced by detecting leakage flux from the reproducing portion by the magnetic head. Thus, during reproduction, no magnetic flux is generated from other portions of the recording layer not irradiated by the light beam. With the arrangement, crosstalk due to leakage flux from adjoining tracks not irradiated by the optical beam can be eliminated. Therefore, track pitches can be made narrower so as to increase recording density of the magnetic recording medium. Further, since crosstalk from adjoining tracks is eliminated, a high S/N can be achieved.

摘要翻译： 一种磁记录介质，其具有由补偿温度包括在室温内的铁氧体材料制成的记录层和使用该磁记录介质的信息记录再现方法。 在记录期间，当光束投射在记录层上以提高记录部分的温度时，通过施加来自磁头的信号磁场来记录信息。 在再现期间，当光束投射在记录层的再现部分上以升高其温度时，通过由磁头检测来自再现部分的漏磁通来再现信息。 因此，在再现期间，不会由不被光束照射的记录层的其它部分产生磁通量。 利用该布置，可以消除由于未被光束照射的相邻轨道的漏磁通引起的串扰。 因此，可以使轨道间距更窄，以提高磁记录介质的记录密度。 此外，由于消除了来自相邻轨道的串扰，可以实现高S / N。

公开(公告)号：US5631096A

公开(公告)日：1997-05-20

申请号：US400464

申请日：1995-03-07

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

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

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

CPC分类号： G11B11/10508 ,  G11B11/10515 ,  G11B11/10586 ,  G11B11/10521 ,  Y10S428/90

摘要： A magneto-optical memory device is provided with a base whereon a first magnetic film which exhibits in-plane magnetization at room temperature and exhibits perpendicular magnetization at above room temperature, a second magnetic film having its Curie temperature above room temperature; and a third magnetic film having its Curie temperature set above the Curie temperature of the second magnetic film, which exhibits perpendicular magnetization in a temperature range between room temperature and Curie temperature are laminated in this order. When recording, the temperature of the third magnetic film is raised to the vicinity of its Curie temperature, and information is recorded thereon by an external magnetic field. As the magnetization of the second magnetic film having a temperature rise above its Curie temperature disappears, an exchange coupling force is not exerted between the first magnetic film and the third magnetic film. In the above arrangement, since the effect from the magnetization of the first magnetic film can be avoided, information can be recorded on the third magnetic film by a small external magnetic field, thereby permitting a reduction in electric power consumption and in the size of the apparatus.

摘要翻译： 磁光存储器件设置有第一磁性膜的基底，第一磁性膜在室温下表现出平面内的磁化强度，并且在室温以上表现出垂直的磁化强度，第二磁性膜的居里温度高于室温; 并且将其居里温度设定在高于室温和居里温度之间的温度范围内的垂直磁化强度的第二磁性膜的居里温度的第三磁性膜依次层叠。 当记录时，第三磁性膜的温度升高到其居里温度附近，并且通过外部磁场在其上记录信息。 随着具有高于其居里温度的温度升高的第二磁性膜的磁化消失，在第一磁性膜和第三磁性膜之间不产生交换耦合力。 在上述结构中，由于可以避免第一磁性膜的磁化的影响，所以可以通过小的外部磁场将信息记录在第三磁性膜上，从而能够降低电力消耗和 仪器。