WO2002029788A1 - Disk unit - Google Patents

Disk unit Download PDF

Info

Publication number
WO2002029788A1
WO2002029788A1 PCT/JP2001/008737 JP0108737W WO0229788A1 WO 2002029788 A1 WO2002029788 A1 WO 2002029788A1 JP 0108737 W JP0108737 W JP 0108737W WO 0229788 A1 WO0229788 A1 WO 0229788A1
Authority
WO
Grant status
Application
Patent type
Prior art keywords
control voltage
peak level
vca
applied
fcm signal
Prior art date
Application number
PCT/JP2001/008737
Other languages
French (fr)
Inventor
Koichi Tada
Toshihide Hamaguchi
Tadashi Okajima
Original Assignee
Sanyo Electric 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

Links

Classifications

    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10Digital recording or reproducing
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/004Recording, reproducing or erasing methods; Read, write or erase circuits therefor
    • G11B7/005Reproducing
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B11/00Recording 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
    • G11B11/10Recording 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
    • G11B11/105Recording 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 thermo-magnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
    • G11B11/1055Disposition or mounting of transducers relative to record carriers
    • G11B11/10556Disposition or mounting of transducers relative to record carriers with provision for moving or switching or masking the transducers in or out of their operative position
    • G11B11/10563Access of indexed parts
    • G11B11/10565Marks for track change, e.g. prepits, gray codes
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/007Arrangement of the information on the record carrier, e.g. form of tracks, actual track shape, e.g. wobbled, or cross-section, e.g. v-shaped; Sequential information structures, e.g. sectoring or header formats within a track
    • G11B7/00745Sectoring or header formats within a track

Abstract

A disk unit (10) including a VCA (36) to which a first control voltage and a second control voltage are applied at different timings. The VCA (36) amplifies an FCM signal at a gain corresponding to an applied control voltage, the peak level of the amplified FCM signal being detected by a peak-hold circuit (38). A DSP (44) calculates an optimum control voltage providing an optimum peak level based on the peak level of an FCM signal to which a gain corresponding to the first control voltage is assigned and on the peak level of an FCM signal to which a gain corresponding to the second control voltage is assigned. Then, the calculated optimum control voltage is applied to the VCA (36).
PCT/JP2001/008737 2000-10-05 2001-10-03 Disk unit WO2002029788A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2000-305610 2000-10-05
JP2000305610A JP2002117535A (en) 2000-10-05 2000-10-05 Disk device

Publications (1)

Publication Number Publication Date
WO2002029788A1 true true WO2002029788A1 (en) 2002-04-11

Family

ID=18786435

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2001/008737 WO2002029788A1 (en) 2000-10-05 2001-10-03 Disk unit

Country Status (2)

Country Link
JP (1) JP2002117535A (en)
WO (1) WO2002029788A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0982031A (en) * 1995-09-14 1997-03-28 Sony Corp Apparatus and method for gain control as well as reproducing apparatus
WO1998054703A1 (en) * 1997-05-28 1998-12-03 Sanyo Electric Co., Ltd. Recording medium and reproducing apparatus therefor
WO1999040576A1 (en) * 1998-02-06 1999-08-12 Sanyo Electric Co., Ltd. Optical disc device
JPH11306686A (en) * 1998-04-21 1999-11-05 Sony Corp Signal processing circuit
WO2001088907A1 (en) * 2000-05-19 2001-11-22 Sanyo Electric Co., Ltd. Disk reproducing device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0982031A (en) * 1995-09-14 1997-03-28 Sony Corp Apparatus and method for gain control as well as reproducing apparatus
WO1998054703A1 (en) * 1997-05-28 1998-12-03 Sanyo Electric Co., Ltd. Recording medium and reproducing apparatus therefor
WO1999040576A1 (en) * 1998-02-06 1999-08-12 Sanyo Electric Co., Ltd. Optical disc device
JPH11306686A (en) * 1998-04-21 1999-11-05 Sony Corp Signal processing circuit
WO2001088907A1 (en) * 2000-05-19 2001-11-22 Sanyo Electric Co., Ltd. Disk reproducing device

Also Published As

Publication number Publication date Type
JP2002117535A (en) 2002-04-19 application

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DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
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122 Ep: pct application non-entry in european phase