公开(公告)号：EP0368194A3

公开(公告)日：1992-03-04

申请号：EP89120477.8

申请日：1989-11-06

申请人： HITACHI, LTD. ,  Hitachi Maxell Ltd.

发明人： Kirino, Fumiyoshi Sanikopo Takaidohigashi 401 ,  Miyamoto, Harukazu ,  Okamine, Shigenori ,  Ogihara, Noriyuki ,  Takahashi, Masahiko ,  Ohta, Norio ,  Niihara, Toshio

IPC分类号： G11B11/10

CPC分类号： G11B11/1053 ,  G11B11/10508 ,  G11B11/10519 ,  G11B11/10586 ,  G11B11/10589 ,  G11B11/10591 ,  G11B11/10593 ,  Y10S428/90

摘要： In a magneto-optical disk for recording, reproduction or erasing with a laser beam, which comprises a film of four-layer structure consisting of a first dielectric layer (2), a magneto-optical recording layer (3), a second dielectric layer (4) and a metallic layer (5), laid on a disk substrate (1) provided with guide tracks, temperature distribution of the magneto-optical recording layer (3) is controlled by controlling the thermal diffusivity of the metallic layer (5), and recording/reproduction/erasing repetition characteristics are improved thereby. In the disk of the present structure, the temperature is elevated in a broader area from the center of laser beam, and thus a thoroughly broad erasing domain width taking a track offset into account can be obtained and not recording domains remain after the erasing. The reproduced signal output is increased by 4 dB, as compared with that obtained by a disk of three-layer structure without any metallic layer, because the beam utilization efficiency is increased owing to both Kerr effect and Faraday effect. When the disk of the present structure is subjected to field modulation recording, tails of arrow-feather-shaped recording domains peculiar to the field modulation recording can be shortened and interbit interferences can be overcome, resulting in an increase in C/N (S/N) ratio and the high density recording can be made. By endowing a Kerr enhancement action to the second dielectric layer (4) and a protective action on the magneto-optical layer (3) to the first dielectric layer (2), only the reliability can be improved without lowering the C/N ratio. By improving the corrosion resistance of the magneto-optical recording layer, the first dielectric layer (2) can be omitted to the contrary, and a magneto-optical disk of simple structure can be obtained and used as memory for domestic applications or communication fields.

摘要翻译： 在由激光束进行记录，再现或擦除的磁光盘中，该磁光盘包括由第一介质层（2），磁光记录层（3），第二介质层 （5）的热扩散率来控制所述磁光记录层（3）的温度分布，所述磁光记录层（3）的温度分布通过控制所述金属层（5）的热扩散率来控制，所述金属层（5） 从而改善记录/再现/擦除重复特性。 在本结构的光盘中，温度从激光束的中心在更宽的区域内升高，因此可以获得考虑轨道偏移的彻底宽的擦除区域宽度，并且在擦除之后不会留下记录区域。 由于克尔效应和法拉第效应两者都增加了光束利用效率，与由没有任何金属层的三层结构盘所获得的信号相比，再现信号输出增加了4dB。 当本结构的盘受到场调制记录时，可以缩短场调制记录特有的箭形羽状记录域的尾部，并且可以克服码间干扰，导致C / N（S / N）比例并且可以进行高密度记录。 通过赋予第二电介质层（4）克尔增强作用和在磁光层（3）上对第一电介质层（2）的保护作用，可以在不降低C / N比的情况下仅提高可靠性。 通过改善磁光记录层的耐腐蚀性，相反可以省略第一电介质层（2），并且可以获得结构简单的磁光盘并将其用作家庭应用或通信领域的存储器。

公开(公告)号：EP0368194B1

公开(公告)日：1998-06-17

申请号：EP89120477.8

申请日：1989-11-06

申请人： HITACHI, LTD. ,  Hitachi Maxell Ltd.

发明人： Kirino, Fumiyoshi Sanikopo Takaidohigashi 401 ,  Miyamoto, Harukazu ,  Okamine, Shigenori ,  Ogihara, Noriyuki ,  Takahashi, Masahiko ,  Ohta, Norio ,  Niihara, Toshio

IPC分类号： G11B11/10

CPC分类号： G11B11/1053 ,  G11B11/10508 ,  G11B11/10519 ,  G11B11/10586 ,  G11B11/10589 ,  G11B11/10591 ,  G11B11/10593 ,  Y10S428/90

公开(公告)号：EP0368194A2

公开(公告)日：1990-05-16

申请号：EP89120477.8

申请日：1989-11-06

申请人： HITACHI, LTD. ,  Hitachi Maxell Ltd.

发明人： Kirino, Fumiyoshi Sanikopo Takaidohigashi 401 ,  Miyamoto, Harukazu ,  Okamine, Shigenori ,  Ogihara, Noriyuki ,  Takahashi, Masahiko ,  Ohta, Norio ,  Niihara, Toshio

IPC分类号： G11B11/10

CPC分类号： G11B11/1053 ,  G11B11/10508 ,  G11B11/10519 ,  G11B11/10586 ,  G11B11/10589 ,  G11B11/10591 ,  G11B11/10593 ,  Y10S428/90

摘要： In a magneto-optical disk for recording, reproduction or erasing with a laser beam, which comprises a film of four-layer structure consisting of a first dielectric layer (2), a magneto-optical recording layer (3), a second dielectric layer (4) and a metallic layer (5), laid on a disk substrate (1) provided with guide tracks, temperature distribution of the magneto-optical recording layer (3) is controlled by controlling the thermal diffusivity of the metallic layer (5), and recording/reproduction/erasing repetition characteristics are improved thereby. In the disk of the present structure, the temperature is elevated in a broader area from the center of laser beam, and thus a thoroughly broad erasing domain width taking a track offset into account can be obtained and not recording domains remain after the erasing. The reproduced signal output is increased by 4 dB, as compared with that obtained by a disk of three-layer structure without any metallic layer, because the beam utilization efficiency is increased owing to both Kerr effect and Faraday effect. When the disk of the present structure is subjected to field modulation recording, tails of arrow-feather-shaped recording domains peculiar to the field modulation recording can be shortened and interbit interferences can be overcome, resulting in an increase in C/N (S/N) ratio and the high density recording can be made. By endowing a Kerr enhancement action to the second dielectric layer (4) and a protective action on the magneto-optical layer (3) to the first dielectric layer (2), only the reliability can be improved without lowering the C/N ratio. By improving the corrosion resistance of the magneto-optical recording layer, the first dielectric layer (2) can be omitted to the contrary, and a magneto-optical disk of simple structure can be obtained and used as memory for domestic applications or communication fields.

摘要翻译： 在用于用激光束进行记录，再现或擦除的磁光盘中，其包括由第一介电层（2），磁光记录层（3），第二电介质层 （4）和设置有导轨的盘基板（1）上的金属层（5），通过控制金属层（5）的热扩散率来控制磁光记录层（3）的温度分布， ，并且由此提高记录/再现/擦除重复特性。 在本结构的盘中，从激光束的中心向温度升高的范围，因此可以获得考虑到磁道偏移的彻底宽的擦除域宽度，并且在擦除之后不会保留记录域。 与由没有任何金属层的三层结构的盘相比，再现信号输出增加了4dB，因为由于克尔效应和法拉第效应都增加了光束利用效率。 当对本结构的盘进行现场调制记录时，可以缩短场调制记录特有的箭头形状的记录区的尾部，并克服间隙干扰，导致C / N（S / N）比，并且可以进行高密度记录。 通过向第二电介质层（4）赋予克尔增强作用和对第一电介质层（2）的磁光层（3）的保护作用，仅在不降低C / N比的情况下可以提高可靠性。 通过提高磁光记录层的耐腐蚀性，可以省略第一介电层（2），并且可以获得简单结构的磁光盘并将其用作家用或通信领域的存储器。