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 mediumInfo
- 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
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.
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)
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 |
-
1980
- 1980-11-21 JP JP16445680A patent/JPS5788540A/en active Pending
Cited By (27)
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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