JPS643842A - Magneto-optical disk device - Google Patents

Magneto-optical disk device

Info

Publication number
JPS643842A
JPS643842A JP15811987A JP15811987A JPS643842A JP S643842 A JPS643842 A JP S643842A JP 15811987 A JP15811987 A JP 15811987A JP 15811987 A JP15811987 A JP 15811987A JP S643842 A JPS643842 A JP S643842A
Authority
JP
Japan
Prior art keywords
magneto
differential amplifier
detected
photodetecting
switch element
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
JP15811987A
Other languages
Japanese (ja)
Inventor
Tatsuaki Sakurai
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
Priority to JP15811987A priority Critical patent/JPS643842A/en
Publication of JPS643842A publication Critical patent/JPS643842A/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
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B13/00—Recording simultaneously or selectively by methods covered by different main groups among G11B3/00, G11B5/00, G11B7/00 and G11B9/00; Record carriers therefor not otherwise provided for; Reproducing therefrom not otherwise provided for
    • G11B13/04—Recording simultaneously or selectively by methods covered by different main groups among G11B3/00, G11B5/00, G11B7/00 and G11B9/00; Record carriers therefor not otherwise provided for; Reproducing therefrom not otherwise provided for magnetically or by magnetisation and optically or by radiation, for changing or sensing optical properties

Abstract

PURPOSE:To detect a magneto-optical signal and an address signal selectively from an independent differential amplifier and to simplify circuit constitution by providing a switch element on the output side of one of photodetecting elements. CONSTITUTION:When the switch element 11 is turned off, the difference in the quantity of photodetection between the photodetecting elements 6 and 7 is calculated by the differential amplifier 8 and a magneto-optical signal is detected. When the address signal is detected, on the other hand, the switch element 11 is turned on to ground the output side of the photodetecting element 7, whose light quantity is eliminated apparently; and the differential amplifier 8 amplifies only the quantity of light photodetected on the side of the photodetecting element 6 and the address signal can be detected with the output of the differential amplifier 8.
JP15811987A 1987-06-25 1987-06-25 Magneto-optical disk device Pending JPS643842A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15811987A JPS643842A (en) 1987-06-25 1987-06-25 Magneto-optical disk device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15811987A JPS643842A (en) 1987-06-25 1987-06-25 Magneto-optical disk device

Publications (1)

Publication Number Publication Date
JPS643842A true JPS643842A (en) 1989-01-09

Family

ID=15664715

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15811987A Pending JPS643842A (en) 1987-06-25 1987-06-25 Magneto-optical disk device

Country Status (1)

Country Link
JP (1) JPS643842A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5453403A (en) * 1994-10-24 1995-09-26 Chartered Semiconductor Manufacturing Pte, Ltd. Method of beveled contact opening formation
US5864926A (en) * 1996-09-09 1999-02-02 Rasmussen Gmbh Spring band clamp

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5453403A (en) * 1994-10-24 1995-09-26 Chartered Semiconductor Manufacturing Pte, Ltd. Method of beveled contact opening formation
US5864926A (en) * 1996-09-09 1999-02-02 Rasmussen Gmbh Spring band clamp

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