JPS57200961A - Reader in optical magnetic disk recording and reproducing system - Google Patents

Reader in optical magnetic disk recording and reproducing system

Info

Publication number
JPS57200961A
JPS57200961A JP56086153A JP8615381A JPS57200961A JP S57200961 A JPS57200961 A JP S57200961A JP 56086153 A JP56086153 A JP 56086153A JP 8615381 A JP8615381 A JP 8615381A JP S57200961 A JPS57200961 A JP S57200961A
Authority
JP
Japan
Prior art keywords
mirror
light
laser light
optical magnetic
reflected
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
JP56086153A
Other languages
Japanese (ja)
Inventor
Hideki Hatano
Takasumi Tajiri
Masaru Otaki
Shigeru 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.)
Pioneer Corp
Original Assignee
Pioneer Corp
Pioneer Electronic 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 Pioneer Corp, Pioneer Electronic Corp filed Critical Pioneer Corp
Priority to JP56086153A priority Critical patent/JPS57200961A/en
Publication of JPS57200961A publication Critical patent/JPS57200961A/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

Landscapes

  • Optical Head (AREA)

Abstract

PURPOSE:To obtain an output whose S/N ratio is small, by separating a laser light by a half-mirror, making one of them irraidate an optical magnetic recording disk, forming a reflected light, making it pass through a photodetector, and after that, photoelectrically convert the other as it is, and comparing and amplifying both of them. CONSTITUTION:A laser light from a laser light source 1 irradiates a thin film 5a of an optical magnetid disk 5 through a half-mirror 2, a reflector 3 and a lens 4, and a polarized light due to a Kerr effect is reflected. The reflected light is returned to the half-mirror 2 through the same path, and is photoelectrically converted 9 throgh a photodetector 7 whose transmittivity is varied by an angle of deflection. On the other hand, the light from the light source 1 is photoelectrically converted 10 through the half-mirror 2, and is attenuated 14 as necessary. Both signals are amplified 11, 12, respectively, and its outputs are differentially amplified 13. In this way, it is possible to obtain a signal being excellent in its S/N ratio, which has offset a noise by the differential amplifier 13.
JP56086153A 1981-06-04 1981-06-04 Reader in optical magnetic disk recording and reproducing system Pending JPS57200961A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP56086153A JPS57200961A (en) 1981-06-04 1981-06-04 Reader in optical magnetic disk recording and reproducing system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56086153A JPS57200961A (en) 1981-06-04 1981-06-04 Reader in optical magnetic disk recording and reproducing system

Publications (1)

Publication Number Publication Date
JPS57200961A true JPS57200961A (en) 1982-12-09

Family

ID=13878787

Family Applications (1)

Application Number Title Priority Date Filing Date
JP56086153A Pending JPS57200961A (en) 1981-06-04 1981-06-04 Reader in optical magnetic disk recording and reproducing system

Country Status (1)

Country Link
JP (1) JPS57200961A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6093649A (en) * 1983-10-27 1985-05-25 Matsushita Electric Ind Co Ltd Method for removing noise in optical pickup of semiconductor laser
EP0156058A2 (en) * 1983-08-06 1985-10-02 Brother Kogyo Kabushiki Kaisha Magneto-optical reading apparatus
JPS61208644A (en) * 1985-03-13 1986-09-17 Sharp Corp Optical head

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS528409B1 (en) * 1967-06-02 1977-03-09

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS528409B1 (en) * 1967-06-02 1977-03-09

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0156058A2 (en) * 1983-08-06 1985-10-02 Brother Kogyo Kabushiki Kaisha Magneto-optical reading apparatus
US5007021A (en) * 1983-08-06 1991-04-09 Brother Kogyo Kabushiki Kaisha Magneto-optical data reading apparatus
JPS6093649A (en) * 1983-10-27 1985-05-25 Matsushita Electric Ind Co Ltd Method for removing noise in optical pickup of semiconductor laser
JPS61208644A (en) * 1985-03-13 1986-09-17 Sharp Corp Optical head

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