公开(公告)号：DE69324858T2

公开(公告)日：1999-10-14

申请号：DE69324858

申请日：1993-02-19

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  FUJITA GORO

IPC: G11B7/0045 ,  G11B7/005 ,  G11B7/007 ,  G11B7/09 ,  G11B7/14 ,  G11B7/26 ,  G11B20/14 ,  H03M5/14 ,  G11B7/00 ,  G11B7/095

Abstract: An optical recording medium on which information data is to be recorded and on which an n-th recording track is located at a distance from the (n-1)th recording track preceding the n-th recording track in a recording region which is narrower than the diameter of a spot of a light beam radiated on the recording area, with recording data obtained on logical processing with recording data recorded on the (n-1)th recording track being recorded on the n-th recording track for increasing the storage capacity of information data, is disclosed. A return beam of a light beam radiated across two neighboring recording tracks on the optical recording medium is detected by a detector having first and second light receiving sections having a boundary line extending parallel to the recording track of the optical recording medium for reading out the information recorded on the optical recording medium based on the level of a sum or difference signal of the output signals of the first and second light receiving sections.

公开(公告)号：EP0579843A4

公开(公告)日：1996-05-08

申请号：EP93903326

申请日：1993-02-08

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  SEO KATSUHIRO ,  SAITO KIMIHIRO ,  TOYOTA KIYOSHI

IPC: G02B5/04 ,  G02B5/30 ,  G11B7/12 ,  G11B7/13 ,  G11B7/135 ,  G11B11/105 ,  G11B11/10

CPC classification number: G11B7/131 ,  G02B5/04 ,  G02B5/3083 ,  G11B7/123 ,  G11B7/1356 ,  G11B7/1359 ,  G11B7/1367 ,  G11B11/10543

Abstract: An optical pickup apparatus has a laser beam source (11), a polarized beam splitter (14) and an objective lens (13), all being aligned with an optical axis (0-0'). The beam emitted from the laser beam source (11) is projected onto a recording surface (1a) of a magneto-optical recording medium (1) as a focused beam, and a predetermined polarization component included in reflected light from the recording surface (1a) of the magneto-optical recording medium (1) is separated with the polarized beam splitter (14) and picked up. In the optical pickup apparatus, between the polarized beam splitter (14) and the objective lens (13), provided is a phase varying means by which the phase of the beam passed through one side of the optical axis (0-0') is made different from the phase of the beam passed through the other side of the optical axis (0-0') by a predetermined angle. As the phase shifting means, a half-wave plate (15), a prism (39) of a retardation type, or a composite optically active plate (52) can be used. On the side orthogonal to the phase varying means (14), further provided is a beam sensing element for sensing light polarized by the polarized beam splitter.

公开(公告)号：DE69331163D1

公开(公告)日：2001-12-20

申请号：DE69331163

申请日：1993-02-19

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  FUJITA GORO

IPC: G11B7/0045 ,  G11B7/005 ,  G11B7/007 ,  G11B7/09 ,  G11B7/14 ,  G11B7/26 ,  G11B20/14 ,  H03M5/14 ,  G11B7/00 ,  G11B7/095

Abstract: An optical recording medium on which information data is to be recorded and on which an n-th recording track is located at a distance from the (n-1)th recording track preceding the n-th recording track in a recording region which is narrower than the diameter of a spot of a light beam radiated on the recording area, with recording data obtained on logical processing with recording data recorded on the (n-1)th recording track being recorded on the n-th recording track for increasing the storage capacity of information data, is disclosed. A return beam of a light beam radiated across two neighboring recording tracks on the optical recording medium is detected by a detector having first and second light receiving sections having a boundary line extending parallel to the recording track of the optical recording medium for reading out the information recorded on the optical recording medium based on the level of a sum or difference signal of the output signals of the first and second light receiving sections.

公开(公告)号：DE69219683T2

公开(公告)日：1997-09-11

申请号：DE69219683

申请日：1992-07-10

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI

IPC: G11B7/135 ,  G11B7/125 ,  G11B11/10 ,  G11B11/105 ,  G11B7/13

Abstract: An optical pickup device includes an optical isolator (6, 8) provided in a beam path of an optical system (3, 8, 6, 5) for modulating the laser beam radiated from an end face (1a) of a semiconductor laser device (1) and returning it to an end face (1a) of the semiconductor laser device (1), and a detector (2) for detecting changes in an output of the return beam from the other face (1b) of the semiconductor laser device (1). The optical isolator (6, 8) is adapted to transmit a beam component (P-wave) having the same plane of polarization as that of the laser beam. The magneto-optical recording medium (9) may be reproduced by an optical system without employing a differential optical system.

公开(公告)号：DE69219683D1

公开(公告)日：1997-06-19

申请号：DE69219683

申请日：1992-07-10

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI

IPC: G11B7/135 ,  G11B7/125 ,  G11B11/10 ,  G11B11/105 ,  G11B7/13

Abstract: An optical pickup device includes an optical isolator (6, 8) provided in a beam path of an optical system (3, 8, 6, 5) for modulating the laser beam radiated from an end face (1a) of a semiconductor laser device (1) and returning it to an end face (1a) of the semiconductor laser device (1), and a detector (2) for detecting changes in an output of the return beam from the other face (1b) of the semiconductor laser device (1). The optical isolator (6, 8) is adapted to transmit a beam component (P-wave) having the same plane of polarization as that of the laser beam. The magneto-optical recording medium (9) may be reproduced by an optical system without employing a differential optical system.

公开(公告)号：AT104795T

公开(公告)日：1994-05-15

申请号：AT87904732

申请日：1987-07-16

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  KITASHINAGAWA ,  AOKI YOSHIO

IPC: G11B5/02 ,  G11B11/10

公开(公告)号：CA1310120C

公开(公告)日：1992-11-10

申请号：CA566318

申请日：1988-05-09

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  OGAWA HIROSHI

IPC: G11B11/10 ,  G11B11/105

Abstract: An apparatus for reproducing a magneto-optical disk which is adapted to intermittently irradiate a magneto-optical disk with a light beam emitted from a laser light source at a predetermined sampling period, detect a polarized component of the light beam emitted from the laser light source and reflected from the disk by detecting elements, derive the reproduced output of an information signal recorded on the magneto-optical disk by taking the difference between the detected outputs from the respective detecting elements, and in which there is provided a random noise removing circuit at the rear stage of the detecting elements for removing photo-electric converting noises generated in the detecting elements.

公开(公告)号：AU583968B2

公开(公告)日：1989-05-11

申请号：AU6659386

申请日：1986-12-16

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  KAWAKUBO OSAMU ,  AOKI YOSHIO

IPC: G11B5/02 ,  G11B11/10 ,  G11B11/105 ,  G11B13/00 ,  G11B13/04 ,  G11B7/26

Abstract: A magneto-optical recording technique comprises: preparing a magneto-optical recording medium (10) comprising a magneto-optical recording layer (12) and a bias magnetic layer (14) formed on a transparent substrate (11), the recording layer (12) having a Curie temperature higher than room temperature, the bias magnetic layer (14) having a compensation temperature lower than a Curie temperature, and the recording layer (12) and the bias magnetic layer (14) being superposed with a non-magnetic layer (13) therebetween; and applying heating (for example by means of a laser beam L.B) to the magneto-optical recording medium (10) at first and second heating power levels, the first level being sufficient to heat the recording layer (12) to a temperature higher than the Curie temperature of the recording layer (12) and to heat the bias magnetic layer (14) to a temperature higher than the compensation temperature of the bias magnetic layer (14), and the second level being sufficient to heat the recording layer (12) to a temperature higher than the Curie temperature of the recording layer (12) while keeping the bias magnetic layer (14) below the compensation temperature of the bias magnetic layer (14).

公开(公告)号：DE69331163T2

公开(公告)日：2002-04-18

申请号：DE69331163

申请日：1993-02-19

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  FUJITA GORO

IPC: G11B7/0045 ,  G11B7/005 ,  G11B7/007 ,  G11B7/09 ,  G11B7/14 ,  G11B7/26 ,  G11B20/14 ,  H03M5/14 ,  G11B7/00 ,  G11B7/095

Abstract: An optical recording medium on which information data is to be recorded and on which an n-th recording track is located at a distance from the (n-1)th recording track preceding the n-th recording track in a recording region which is narrower than the diameter of a spot of a light beam radiated on the recording area, with recording data obtained on logical processing with recording data recorded on the (n-1)th recording track being recorded on the n-th recording track for increasing the storage capacity of information data, is disclosed. A return beam of a light beam radiated across two neighboring recording tracks on the optical recording medium is detected by a detector having first and second light receiving sections having a boundary line extending parallel to the recording track of the optical recording medium for reading out the information recorded on the optical recording medium based on the level of a sum or difference signal of the output signals of the first and second light receiving sections.

公开(公告)号：DE69330503D1

公开(公告)日：2001-08-30

申请号：DE69330503

申请日：1993-02-19

Applicant: SONY CORP

Inventor： HORIMAI HIDEYOSHI ,  FUJITA GORO

IPC: G11B7/0045 ,  G11B7/005 ,  G11B7/007 ,  G11B7/09 ,  G11B7/14 ,  G11B7/26 ,  G11B20/14 ,  H03M5/14 ,  G11B7/00 ,  G11B7/095

Abstract: An optical recording medium on which information data is to be recorded and on which an n-th recording track is located at a distance from the (n-1)th recording track preceding the n-th recording track in a recording region which is narrower than the diameter of a spot of a light beam radiated on the recording area, with recording data obtained on logical processing with recording data recorded on the (n-1)th recording track being recorded on the n-th recording track for increasing the storage capacity of information data, is disclosed. A return beam of a light beam radiated across two neighboring recording tracks on the optical recording medium is detected by a detector having first and second light receiving sections having a boundary line extending parallel to the recording track of the optical recording medium for reading out the information recorded on the optical recording medium based on the level of a sum or difference signal of the output signals of the first and second light receiving sections.