JPS5788540A - Method and apparatus for information read-in of optical magnetic recording medium - Google Patents

Method and apparatus for information read-in of optical magnetic recording medium

Info

Publication number
JPS5788540A
JPS5788540A JP16445680A JP16445680A JPS5788540A JP S5788540 A JPS5788540 A JP S5788540A JP 16445680 A JP16445680 A JP 16445680A JP 16445680 A JP16445680 A JP 16445680A JP S5788540 A JPS5788540 A JP S5788540A
Authority
JP
Japan
Prior art keywords
light
information
beam splitter
split
optical
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.)
Pending
Application number
JP16445680A
Other languages
Japanese (ja)
Inventor
Kiichi Kato
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.)
Olympus Corp
Original Assignee
Olympus Corp
Olympus Optical Co Ltd
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 Olympus Corp, Olympus Optical Co Ltd filed Critical Olympus Corp
Priority to JP16445680A priority Critical patent/JPS5788540A/en
Publication of JPS5788540A publication Critical patent/JPS5788540A/en
Pending 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

Abstract

PURPOSE:To detect the split light without using a polarizer, etc. and to enable optical reading of information with good S/N, by making opposite the direction of polarization of >=2 light flux parts symmetrical to an optical axis and separately detecting the light fluxes. CONSTITUTION:A laser light flux via a relay lens 22 is reflected by a beam splitter 23 to be a linear polarized light and becomes a light flux which is split into two symmetrically with respect to an optical axis at 1/2 wavelength plates 24B, 24A where the transmitted light is polarized oppositely to each other. The light fluxes become reflected light fluxes in which the polarized plane is changed in accordance with the information on a magnetic disc 26 and separately detected at detectors 27A, 27B via the 1/2 wavelength plates 24A, 24B and beam splitter 23 to read in the information according to differential amplification. Through the optical constitution consisting of the beam splitter splitting the reflected light into two, which is unnecessary for a polarizer every split reflection light and simple and easy for the adjustment, the optical reading of information can be made in an excellent manner with 7<S/N light amount loss.
JP16445680A 1980-11-21 1980-11-21 Method and apparatus for information read-in of optical magnetic recording medium Pending JPS5788540A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP16445680A JPS5788540A (en) 1980-11-21 1980-11-21 Method and apparatus for information read-in of optical magnetic recording medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP16445680A JPS5788540A (en) 1980-11-21 1980-11-21 Method and apparatus for information read-in of optical magnetic recording medium

Publications (1)

Publication Number Publication Date
JPS5788540A true JPS5788540A (en) 1982-06-02

Family

ID=15793516

Family Applications (1)

Application Number Title Priority Date Filing Date
JP16445680A Pending JPS5788540A (en) 1980-11-21 1980-11-21 Method and apparatus for information read-in of optical magnetic recording medium

Country Status (1)

Country Link
JP (1) JPS5788540A (en)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57169947A (en) * 1981-04-14 1982-10-19 Sharp Corp Magnetic optical head
JPS58128037A (en) * 1982-01-22 1983-07-30 Sharp Corp Magnetooptical head
JPS5979446A (en) * 1982-10-28 1984-05-08 Sharp Corp Magneto-optical head
JPS5982646A (en) * 1982-10-29 1984-05-12 Sharp Corp Optomagnetic storage device
JPS6054226U (en) * 1983-09-20 1985-04-16 オリンパス光学工業株式会社 Magneto-optical pickup device
JPS6190346A (en) * 1984-10-11 1986-05-08 Hitachi Ltd Photo-electromagnetic reproducing device
JPS63193355A (en) * 1987-02-06 1988-08-10 Nec Corp Magneto-optical head
JPS63244346A (en) * 1987-03-30 1988-10-11 Matsushita Electric Ind Co Ltd Magneto-optical disk device
US4853923A (en) * 1985-12-12 1989-08-01 Nikon Corporation Maneto-optical recording apparatus with path length compensated dual photo-electric conversion
JPH0329138A (en) * 1990-04-13 1991-02-07 Sanyo Electric Co Ltd Information reader
WO1993016469A1 (en) * 1992-02-07 1993-08-19 Sony Corporation Phase varying device, and optical pickup apparatus using the same for magneto-optical storage
JPH06259790A (en) * 1993-11-15 1994-09-16 Canon Inc Optical pickup device
US5416755A (en) * 1985-02-28 1995-05-16 Canon Kabushiki Kaisha Optical pickup using split beams impinging on different photo-detector areas
WO1996015530A1 (en) * 1994-11-10 1996-05-23 Sony Corporation Optical pickup apparatus and optical disk drive apparatus
US5661701A (en) * 1985-02-28 1997-08-26 Canon Kabushiki Kaisha Optical pickup using split beams impinging on different photodetector areas
US5663940A (en) * 1993-11-19 1997-09-02 Sony Corporation Optical pickup apparatus including hologram element

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57169947A (en) * 1981-04-14 1982-10-19 Sharp Corp Magnetic optical head
JPH034976B2 (en) * 1981-04-14 1991-01-24 Sharp Kk
JPH0338663B2 (en) * 1982-01-22 1991-06-11 Sharp Kk
JPS58128037A (en) * 1982-01-22 1983-07-30 Sharp Corp Magnetooptical head
JPS5979446A (en) * 1982-10-28 1984-05-08 Sharp Corp Magneto-optical head
JPH0363139B2 (en) * 1982-10-28 1991-09-30 Sharp Kk
JPS5982646A (en) * 1982-10-29 1984-05-12 Sharp Corp Optomagnetic storage device
JPH0581977B2 (en) * 1982-10-29 1993-11-17 Sharp Kk
JPS6054226U (en) * 1983-09-20 1985-04-16 オリンパス光学工業株式会社 Magneto-optical pickup device
JPS6190346A (en) * 1984-10-11 1986-05-08 Hitachi Ltd Photo-electromagnetic reproducing device
JPH0556584B2 (en) * 1984-10-11 1993-08-19 Hitachi Ltd
US5416755A (en) * 1985-02-28 1995-05-16 Canon Kabushiki Kaisha Optical pickup using split beams impinging on different photo-detector areas
US5661701A (en) * 1985-02-28 1997-08-26 Canon Kabushiki Kaisha Optical pickup using split beams impinging on different photodetector areas
US4853923A (en) * 1985-12-12 1989-08-01 Nikon Corporation Maneto-optical recording apparatus with path length compensated dual photo-electric conversion
JPS63193355A (en) * 1987-02-06 1988-08-10 Nec Corp Magneto-optical head
JPS63244346A (en) * 1987-03-30 1988-10-11 Matsushita Electric Ind Co Ltd Magneto-optical disk device
JPH0329138A (en) * 1990-04-13 1991-02-07 Sanyo Electric Co Ltd Information reader
JPH05777B2 (en) * 1990-04-13 1993-01-06 Sanyo Electric Co
WO1993016469A1 (en) * 1992-02-07 1993-08-19 Sony Corporation Phase varying device, and optical pickup apparatus using the same for magneto-optical storage
US5563869A (en) * 1992-02-07 1996-10-08 Sony Corporation Prism has a plurality of reflective regions each with a predetermined phase difference
US5577018A (en) * 1992-02-07 1996-11-19 Sony Corporation Phase changing apparatus and optical pickup apparatus for magneto-optic storage device using same
US5742577A (en) * 1992-02-07 1998-04-21 Sony Corporation Prism has a plurality of reflective regions each with a predetermined phase difference
US5717667A (en) * 1993-11-11 1998-02-10 Sony Corporation Optical pickup apparatus including an optical rotation device
JPH06259790A (en) * 1993-11-15 1994-09-16 Canon Inc Optical pickup device
US5663940A (en) * 1993-11-19 1997-09-02 Sony Corporation Optical pickup apparatus including hologram element
WO1996015530A1 (en) * 1994-11-10 1996-05-23 Sony Corporation Optical pickup apparatus and optical disk drive apparatus
US5896360A (en) * 1994-11-10 1999-04-20 Sony Corporation Optical pickup device and optical disc driving apparatus having light polarizing hologram

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