JPS57169947A - Magnetic optical head - Google Patents

Magnetic optical head

Info

Publication number
JPS57169947A
JPS57169947A JP5658781A JP5658781A JPS57169947A JP S57169947 A JPS57169947 A JP S57169947A JP 5658781 A JP5658781 A JP 5658781A JP 5658781 A JP5658781 A JP 5658781A JP S57169947 A JPS57169947 A JP S57169947A
Authority
JP
Japan
Prior art keywords
polarized
photodetector
error signal
rotated
polarized light
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP5658781A
Other languages
Japanese (ja)
Other versions
JPH034976B2 (en
Inventor
Akira Takahashi
Kenji Oota
Toshihisa Deguchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sharp Corp
Original Assignee
Sharp Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sharp Corp filed Critical Sharp Corp
Priority to JP5658781A priority Critical patent/JPS57169947A/en
Publication of JPS57169947A publication Critical patent/JPS57169947A/en
Publication of JPH034976B2 publication Critical patent/JPH034976B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
    • G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
    • G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
    • G11B11/10532—Heads
    • G11B11/10541—Heads for reproducing
    • G11B11/10543—Heads for reproducing using optical beam of radiation
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
    • G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
    • G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
    • G11B11/1055—Disposition or mounting of transducers relative to record carriers
    • G11B11/10576—Disposition or mounting of transducers relative to record carriers with provision for moving the transducers for maintaining alignment or spacing relative to the carrier

Abstract

PURPOSE:To obtain an error signal with good S/N ratio and to simplify the construction of a head, by using a polarized beam splitter for a photodetector of a magnetooptic head. CONSTITUTION:The beam from a laser 1 passes through a condenser lens 2, a half mirror 7, and a condenser lens 8 and is made incident to a recording medium 9, and the reflection beam passes through the half mirror 7 and a polarized beam splitter 21 and after the polarized plane is rotated, the beam enters the photodetector 21 and a 4-split photodetector 16 via a cylindrical lens 14. A focus error signal and a track error signal are picked up from the 4-split photodetector 16. In this case, the rotation of the polarized plane by Kurr effect of the splitter 21 is dependent on the direction of magnetization of the recording medium 9, and when the polarized light beam splitter 21 is set to the S direction to the polarized light S1 rotated by angle alpha and to the polarized light S2 rotated by angle -alpha, polarized components S'1 and S'2 are obtained at the photodetector 12, and an error signal with the good S/N ratio is obtained and the construction can be simplified.
JP5658781A 1981-04-14 1981-04-14 Magnetic optical head Granted JPS57169947A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5658781A JPS57169947A (en) 1981-04-14 1981-04-14 Magnetic optical head

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5658781A JPS57169947A (en) 1981-04-14 1981-04-14 Magnetic optical head

Publications (2)

Publication Number Publication Date
JPS57169947A true JPS57169947A (en) 1982-10-19
JPH034976B2 JPH034976B2 (en) 1991-01-24

Family

ID=13031306

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5658781A Granted JPS57169947A (en) 1981-04-14 1981-04-14 Magnetic optical head

Country Status (1)

Country Link
JP (1) JPS57169947A (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5829155A (en) * 1981-08-14 1983-02-21 Olympus Optical Co Ltd Information reproducer by photomagnetic system
JPS5977649A (en) * 1982-10-26 1984-05-04 Sanyo Electric Co Ltd Reproducing device of photomagnetic disc
JPS59168951A (en) * 1983-03-16 1984-09-22 Sanyo Electric Co Ltd Optical magnetic disc device
JPS60187955A (en) * 1984-03-07 1985-09-25 Yokogawa Hokushin Electric Corp Photomagnetic disk device
JPS60191450A (en) * 1984-03-09 1985-09-28 Yokogawa Hokushin Electric Corp Photomagnetic disk device
FR2615995A1 (en) * 1987-05-27 1988-12-02 Bull Sa INFORMATION WRITING MODE ON A MAGNETIC RECORDING MEDIUM
US4853923A (en) * 1985-12-12 1989-08-01 Nikon Corporation Maneto-optical recording apparatus with path length compensated dual photo-electric conversion
JPH0246547A (en) * 1988-08-08 1990-02-15 Sharp Corp Magneto-optical memory device
JPH0249242A (en) * 1988-08-10 1990-02-19 Sharp Corp Magneo-optical memory device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5619176A (en) * 1979-07-25 1981-02-23 Mitsubishi Electric Corp Optical information reader
JPS5788540A (en) * 1980-11-21 1982-06-02 Olympus Optical Co Ltd Method and apparatus for information read-in of optical magnetic recording medium

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5619176A (en) * 1979-07-25 1981-02-23 Mitsubishi Electric Corp Optical information reader
JPS5788540A (en) * 1980-11-21 1982-06-02 Olympus Optical Co Ltd Method and apparatus for information read-in of optical magnetic recording medium

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5829155A (en) * 1981-08-14 1983-02-21 Olympus Optical Co Ltd Information reproducer by photomagnetic system
JPH0327977B2 (en) * 1981-08-14 1991-04-17 Olympus Optical Co
JPS5977649A (en) * 1982-10-26 1984-05-04 Sanyo Electric Co Ltd Reproducing device of photomagnetic disc
JPS59168951A (en) * 1983-03-16 1984-09-22 Sanyo Electric Co Ltd Optical magnetic disc device
JPS60187955A (en) * 1984-03-07 1985-09-25 Yokogawa Hokushin Electric Corp Photomagnetic disk device
JPS60191450A (en) * 1984-03-09 1985-09-28 Yokogawa Hokushin Electric Corp Photomagnetic disk device
US4853923A (en) * 1985-12-12 1989-08-01 Nikon Corporation Maneto-optical recording apparatus with path length compensated dual photo-electric conversion
FR2615995A1 (en) * 1987-05-27 1988-12-02 Bull Sa INFORMATION WRITING MODE ON A MAGNETIC RECORDING MEDIUM
JPH0246547A (en) * 1988-08-08 1990-02-15 Sharp Corp Magneto-optical memory device
JPH0249242A (en) * 1988-08-10 1990-02-19 Sharp Corp Magneo-optical memory device

Also Published As

Publication number Publication date
JPH034976B2 (en) 1991-01-24

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