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JPS6489053A - Method for inspecting defect of magneto-optical disc - Google Patents

Method for inspecting defect of magneto-optical disc

Info

Publication number
JPS6489053A
JPS6489053A JP24696387A JP24696387A JPS6489053A JP S6489053 A JPS6489053 A JP S6489053A JP 24696387 A JP24696387 A JP 24696387A JP 24696387 A JP24696387 A JP 24696387A JP S6489053 A JPS6489053 A JP S6489053A
Authority
JP
Japan
Prior art keywords
magneto
optical disc
light beam
detectors
time
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
JP24696387A
Other languages
Japanese (ja)
Inventor
Hisatoku Tanaka
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.)
Sony Corp
Original Assignee
Sony 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 Sony Corp filed Critical Sony Corp
Priority to JP24696387A priority Critical patent/JPS6489053A/en
Publication of JPS6489053A publication Critical patent/JPS6489053A/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

Abstract

PURPOSE:To shorten a inspection time and to reduce false inspections by making a light beam from a light source incident on a magneto-optical disc, supplying the light beam obtained from the photo-electro-magneto-optical disc to at least two detectors and detecting respectively the polarized components of a polarizing plane in directions perpendicular to each other. CONSTITUTION:The light beam from a light source 5 is made incident on a magneto-optical disc 1, the light beam obtained from the magneto-optical disc 1 is supplied to at least two detectors 12A and 12B and the polarized components of the polarizing plane in the directions perpendicular to each other are respectively detected. By obtaining the difference and the sum of the detection outputs of the detectors 12A and 12B, the defect of the magneto- optical disc 1 is inspected. Thus, the magneto-optical disc 1 can be revolved at the time of an inspection at higher speed than used actually and the inspection time can be widely shortened. Since the recording process of the magneto- optical disc 1 is unnecessary, the false detections by data errors, etc., due to a driving device at the time of a recording can be reduced.
JP24696387A 1987-09-30 1987-09-30 Method for inspecting defect of magneto-optical disc Pending JPS6489053A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP24696387A JPS6489053A (en) 1987-09-30 1987-09-30 Method for inspecting defect of magneto-optical disc

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP24696387A JPS6489053A (en) 1987-09-30 1987-09-30 Method for inspecting defect of magneto-optical disc

Publications (1)

Publication Number Publication Date
JPS6489053A true JPS6489053A (en) 1989-04-03

Family

ID=17156327

Family Applications (1)

Application Number Title Priority Date Filing Date
JP24696387A Pending JPS6489053A (en) 1987-09-30 1987-09-30 Method for inspecting defect of magneto-optical disc

Country Status (1)

Country Link
JP (1) JPS6489053A (en)

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