公开(公告)号：EP0913818A1

公开(公告)日：1999-05-06

申请号：EP97930771.7

申请日：1997-07-11

申请人： HITACHI MAXELL, LTD. ,  SANYO ELECTRIC Co., Ltd.

发明人： OONUKI, Satoru ,  YOSHIHIRO, Masafumi ,  NAGAI, Nobuyuki ,  SHIMAZAKI, Katsusuke ,  AWANO, Hiroyuki ,  SHIRAI, Hiroshi ,  OHTA, Norio ,  SUMI, Satoshi ,  YAMAGUCHI, Atsushi

IPC分类号： G11B11/10

CPC分类号： G11B11/10515 ,  G11B7/00745 ,  G11B11/10508 ,  G11B11/10521 ,  G11B11/10528 ,  G11B11/10578 ,  G11B11/10584 ,  G11B11/10593 ,  G11B11/10595 ,  G11B27/19 ,  G11B27/3027

摘要： A magneto-optical recording medium (11) has a second auxiliary magnetic film (4), a first auxiliary magnetic film (5) and a magneto-optical recording film (6) in this order from the laser beam applied side. If the temperatures of the first and second auxiliary magnetic films (4 and 5) exceed their critical temperatures T CR1 and T CR2 , the magnetization of the auxiliary magnetic films is changed from the surface magnetization to the vertical magnetization. The Curie points T C0 , T C1 and T C2 of the magneto-optical recording film (6), the first auxiliary magnetic film (4) and the second auxiliary magnetic film (5) and the critical temperatures T CR1 and T CR2 satisfy the relations room temperature CR2 CR1 C0 , T C1 and T C2 . The thickness of the first auxiliary magnetic film (4) is larger than the tickness of a magnetic wall. After the recording magnetic domain (22) of the magneto-optical recording film (6) is contracted and transferred onto the first auxiliary magnetic film (4) by the reproducing light application, it is expanded and transferred onto the second auxiliary magnetic film (5). Since an amplified reproducing signal can be obtained from an expanded magnetic domain (23), the magneto-optical recording medium is suitable for the reproduction of the high density recording.

摘要翻译： 从激光束施加侧起，磁光记录介质（11）具有第二辅助磁膜（4），第一辅助磁膜（5）和磁光记录膜（6）。 如果第一和第二辅助磁性膜（4和5）的温度超过它们的临界温度TCR1和TCR2，则辅助磁性膜的磁化从表面磁化转变为垂直磁化。 磁光记录膜（6），第一辅助磁性膜（4）和第二辅助磁性膜（5）的居里点TC0，TC1和TC2以及临界温度TCR1和TCR2满足室温

公开(公告)号：EP0915462A1

公开(公告)日：1999-05-12

申请号：EP97930772.5

申请日：1997-07-11

申请人： HITACHI MAXELL, LTD. ,  SANYO ELECTRIC Co., Ltd.

发明人： AWANO, Hiroyuki ,  SHIRAI, Hiroshi ,  YOSHIHIRO, Masafumi ,  OONUKI, Satoru ,  OHTA, Norio ,  SHIMAZAKI, Katsusuke ,  NAGAI, Nobuyuki ,  SUMI, Satoshi ,  YAMAGUCHI, Atsushi

IPC分类号： G11B11/10

CPC分类号： G11B11/10584 ,  G11B11/1051 ,  G11B11/10515 ,  G11B11/10554 ,  G11B11/10586 ,  G11B11/10595 ,  G11B27/19 ,  G11B27/3027

摘要： A magneto-optical recording medium 11 is irradiated with a reproducing light beam 13 so that only a minute magnetic domain 313b, which is subjected to recording in a recording layer 18 and which is smaller than 1/2 of a spot radius of the recording light beam 13, is selected by a gate layer 17 and transferred to a magnetic domain-magnifying and reproducing layer 3. The magnetic domain transferred to the magnetic domain-magnifying and reproducing layer 3 is magnified by using a magnifying and reproducing magnetic field 411 of an alternating magnetic field. A large reproduction signal is obtained from the magnified magnetic domain 419, and the minute magnetic domain can be subjected to reproduction at a high resolving power and at a high S/N ratio. The magnified magnetic domain 419 is reduced by using a reducing reproducing magnetic field 415 of the alternating magnetic field. The gate layer 17 has a thickness which is not less than a thickness of a magnetic wall of the magnetic domain. A non-magnetic layer may be used in place of the gate layer 17.

公开(公告)号：EP0762410A1

公开(公告)日：1997-03-12

申请号：EP95918157.9

申请日：1995-05-10

申请人： HITACHI MAXELL, LTD.

发明人： SHIMAZAKI, Katsusuke ,  YOSHIHIRO, Masafumi ,  SAKEMOTO, Akito ,  OHTA, Norio ,  ISHIZAKI, Osamu ,  OHNUKI, Satoru ,  SUGIYAMA, Toshinori ,  ISHITSUKA, Kazuko

IPC分类号： G11B11/10

CPC分类号： G11B11/10515 ,  G11B11/10502 ,  G11B11/10508 ,  G11B11/1051 ,  G11B11/10521 ,  G11B11/10528 ,  G11B11/1053 ,  G11B11/10534 ,  G11B11/10554 ,  G11B11/10586 ,  G11B11/10595

摘要： On a surface of a transparent substrate 1 having a preformat pattern 2 formed thereon are laminated a first recording layer 4 in which a recording state exists in one different magnetic field region of an applied external magnetic field and a second recording layer 6 in which two recording states exist in magnetic field regions different from that for the first recording layer. As required, dielectric layers 3, 5 and 7, a reflecting layer 8 and a protection layer 9 can be laminated. The 4-valued recording of information becomes possible by assigning information signals "1", "0", "3" and "2" to H 0 , H 1 , H 2 and H 3 , respectively.