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JPS6464156A - Optical information recording and reproducing device - Google Patents

Optical information recording and reproducing device

Info

Publication number
JPS6464156A
JPS6464156A JP63122881A JP12288188A JPS6464156A JP S6464156 A JPS6464156 A JP S6464156A JP 63122881 A JP63122881 A JP 63122881A JP 12288188 A JP12288188 A JP 12288188A JP S6464156 A JPS6464156 A JP S6464156A
Authority
JP
Japan
Prior art keywords
grating
diffraction
light beam
gratings
information recording
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
JP63122881A
Other languages
Japanese (ja)
Inventor
Shigeru Ouchida
Toshiyuki Iguchi
Nobuyuki Baba
Kazuhiro Fujita
Hideo Maeda
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.)
Ricoh Co Ltd
Original Assignee
Ricoh 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 Ricoh Co Ltd filed Critical Ricoh Co Ltd
Publication of JPS6464156A publication Critical patent/JPS6464156A/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
    • 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

Landscapes

  • Optical Head (AREA)

Abstract

PURPOSE:To contrive to miniaturize the titled device and to reduce its cost by providing a deflection split element having a diffraction grating whose grating direction is made different, on an optical path of a reflected light from an information recording medium. CONSTITUTION:A light beam which is reflected by a magneto-optical disk and transmitted through a polarized light beam splitter is made incident on the center between diffraction gratings 30a, 30b of a 2-split diffraction grating 30. The grating 30 is divided into two to the right and left centering around an optical axis, and the diffraction gratings 30a, 30b whose grating directions is made different by inclining each of them, for instance, by 45 deg. each by setting its center line as a boundary are formed on a grating substrate 30c. Accordingly, as for a deflection angle of the light beam which is made incident, the angles sensed by the gratings 30a, 30b are different, and in one grating 30a or 30b, the diffraction efficiency becomes high by a portion containing a (p) wave component, and on the other hand, in the other grating 30b or 30a, the diffraction efficiency becomes low. Therefore, by detecting a difference of both of them, the deflecting direction can be detected. According to this constitution, it becomes unnecessary to use complicated optical parts such as a lambda/2 plate and a Wollaston prism.
JP63122881A 1987-05-20 1988-05-19 Optical information recording and reproducing device Pending JPS6464156A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7621587 1987-05-20

Publications (1)

Publication Number Publication Date
JPS6464156A true JPS6464156A (en) 1989-03-10

Family

ID=13598952

Family Applications (1)

Application Number Title Priority Date Filing Date
JP63122881A Pending JPS6464156A (en) 1987-05-20 1988-05-19 Optical information recording and reproducing device

Country Status (1)

Country Link
JP (1) JPS6464156A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01250905A (en) * 1987-12-24 1989-10-05 Kuraray Co Ltd polarizing optical element
EP1573369B1 (en) * 2002-12-16 2014-07-09 Nokia Corporation Pupil enlarging waveguide device with splitted diffractive grating for balancing diffraction efficiency

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01250905A (en) * 1987-12-24 1989-10-05 Kuraray Co Ltd polarizing optical element
EP1573369B1 (en) * 2002-12-16 2014-07-09 Nokia Corporation Pupil enlarging waveguide device with splitted diffractive grating for balancing diffraction efficiency

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