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公开(公告)号：DE69021173D1
公开(公告)日：1995-08-31
申请号：DE69021173
申请日：1990-11-08
Applicant: IBM
Inventor： TAYEFEH MOROVAT
IPC: G11B11/10 , G11B11/105 , G11B19/02 , G11B27/36
Abstract: A magnetooptic storage member is scanned by a single laser beam. The beam intensity is sufficient to heat a localized area of the storage member to be above the Curie temperature for enabling reversing the residual magnetization of the localized area. Such localized area is subjected to a magnetic bias field for directing which of the residual directions shall be assumed in the localized area. The storage member and laser beam are relatively moved such that a front or leading portion of the localized area does not reach the Curie temperature. The light reflected from this leading portion, which moves with the laser beam relative to the storage member, is detected for indicating the initial residual state of the localized area before any changes are made by the combination of the bias field and the laser beam.
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公开(公告)号：CA2025924C
公开(公告)日：1995-08-01
申请号：CA2025924
申请日：1990-09-21
Applicant: IBM
Inventor： TAYEFEH MOROVAT
Abstract: A magnetooptic player reads magnetooptically recorded signals on a disk by using a differential detector. Intermediate areas on a storage member used to store the magnetooptically record signals are sector marks and ID fields formed by undulations in the surface of the disk. Such sector marks and ID fields are read by detecting the intensity modulation in a reading light beam; for detecting such embossed marks and D-ROM disks, one-half of the differential detector is disabled for facilitating such detection in a differentially arranged detector.
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公开(公告)号：DE69016246T2
公开(公告)日：1995-06-29
申请号：DE69016246
申请日：1990-04-04
Applicant: IBM
Inventor： BLETSHER WARREN LEROY , TAYEFEH MOROVAT , LEWKOWICZ JULIAN
IPC: G11B11/10 , G11B7/00 , G11B7/0045 , G11B7/125 , G11B11/105 , G11B27/36 , G11B7/12
Abstract: Recording operations for an optical disk recorder are calibrated by adjusting recording power level (light intensity) such that a permissible crosstalk can be detected in adjacent erased tracks. Following the power level calibration, pulse duration or width is calibrated for a predetermined symmetry of recorded pulses along the calibration track. Various sequences and procedures are described. Calibration occurs at a plurality of radially spaced-apart tracks.
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公开(公告)号：AU8278191A
公开(公告)日：1992-03-26
申请号：AU8278191
申请日：1991-08-23
Applicant: IBM
Inventor： KULAKOWSKI JOHN EDWARD , MEANS RODNEY JEROME , TAYEFEH MOROVAT
IPC: G11B7/00 , G11B7/0045 , G11B7/0055 , G11B7/007 , G11B7/013 , G11B11/10 , G11B11/105 , G11B20/12 , G11B19/04
Abstract: The present invention relates to a re-writable data storage member (10) comprising a plurality of spaced apart addressable data storage areas (12) for recording and storing data and a plurality of non-data storage areas (15) interposed between adjacent ones of the addressable data storage areas for recording signals not representing data, the storage member being adapted to be scanned in a direction over the storage areas. According to the invention the storage member is characterised in that one of the addressable data storage areas contains first machine readable indicia indicating that the storage member contains data which is not to be changed from any original recording of the data, another of the addressable data storage areas contains second machine readable indicia indicating whether or not the storage member has been erased of data in its entirety, and each of the non-data storage areas contains third machine readable indicia indicating whether or not one of the respective adjacent addressable data storage areas can be written into. The invention also relates to a data storage system comprising a re-writable data storage member as above and to a method of operating such a data storage system.
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Patent Agency Ranking
公开(公告)号：DE69027514T2
公开(公告)日：1997-01-23
申请号：DE69027514
申请日：1990-12-07
Applicant: IBM
Inventor： TAYEFEH MOROVAT
Abstract: The present invention relates to an optical detection circuit comprising detecting means for detecting signals representing both polarisation modulation and intensity modulation in a received light beam. According to the invention the device is characterised in that the detecting means comprises polarisation modulation detection means (32, 33) for detecting two forms of polarisation, and conversion means (40) for selectively inhibiting the portion of the polarisation modulation detection means which detects one of the forms of polarisation so as to convert the polarisation modulation detection means into intensity modulation detection means when required.
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公开(公告)号：DE69120757D1
公开(公告)日：1996-08-14
申请号：DE69120757
申请日：1991-09-16
Applicant: IBM
Inventor： KULAKOWSKI JOHN EDWARD , MEANS RODNEY JEROME , TAYEFEH MOROVAT
IPC: G11B7/00 , G11B7/0045 , G11B7/0055 , G11B7/007 , G11B7/013 , G11B11/10 , G11B11/105 , G11B20/12
Abstract: The present invention relates to a re-writable data storage member (10) comprising a plurality of spaced apart addressable data storage areas (12) for recording and storing data and a plurality of non-data storage areas (15) interposed between adjacent ones of the addressable data storage areas for recording signals not representing data, the storage member being adapted to be scanned in a direction over the storage areas. According to the invention the storage member is characterised in that one of the addressable data storage areas contains first machine readable indicia indicating that the storage member contains data which is not to be changed from any original recording of the data, another of the addressable data storage areas contains second machine readable indicia indicating whether or not the storage member has been erased of data in its entirety, and each of the non-data storage areas contains third machine readable indicia indicating whether or not one of the respective adjacent addressable data storage areas can be written into. The invention also relates to a data storage system comprising a re-writable data storage member as above and to a method of operating such a data storage system.
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公开(公告)号：DE69116039T2
公开(公告)日：1996-07-04
申请号：DE69116039
申请日：1991-03-01
Applicant: IBM
Inventor： FINKELSTEIN BLAIR IAN , TAYEFEH MOROVAT , UENO HIDEO
IPC: G11B7/00 , G11B7/0045 , G11B7/0055 , G11B7/125 , G11B11/10 , G11B11/105 , G11B20/18 , G11B27/36
Abstract: The present invention relates to a method of calibrating a system for the recording and readback of optically detectable data of the type which comprises a record medium (30) formed from a material which is sensitive to optical radiation, means (67) for generating a beam of light (47), means (33) for scanning the beam of light relative to the surface of the medium, means (75) for selectively varying the intensity of the beam of light so as to record data at selected positions on the surface and means (79) for reading back the recorded data. The calibrating method comprises the operation of controlling the recording intensity of the beam of light so that signals from the readback means have a maximum amplitude. According to the invention the operation of controlling the recording intensity comprises utilising the beam of light to record a plurality of test patterns (29) on the surface of the medium each pattern being recorded with a different intensity of the beam of light, reading back the test patterns and generating a readback test signal from each test pattern, detecting the readback test signal having the largest amplitude, and utilising the intensity of the beam of light used to record the test pattern which generates the readback test signal having the largest amplitude for the light beam when it is recording data. The invention also relates to apparatus for implementing the above method of calibrating.
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公开(公告)号：DE69021173T2
公开(公告)日：1996-02-29
申请号：DE69021173
申请日：1990-11-08
Applicant: IBM
Inventor： TAYEFEH MOROVAT
IPC: G11B11/10 , G11B11/105 , G11B19/02 , G11B27/36
Abstract: A magnetooptic storage member is scanned by a single laser beam. The beam intensity is sufficient to heat a localized area of the storage member to be above the Curie temperature for enabling reversing the residual magnetization of the localized area. Such localized area is subjected to a magnetic bias field for directing which of the residual directions shall be assumed in the localized area. The storage member and laser beam are relatively moved such that a front or leading portion of the localized area does not reach the Curie temperature. The light reflected from this leading portion, which moves with the laser beam relative to the storage member, is detected for indicating the initial residual state of the localized area before any changes are made by the combination of the bias field and the laser beam.
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公开(公告)号：HU9403547D0
公开(公告)日：1995-02-28
申请号：HU9403547
申请日：1993-05-19
Applicant: IBM
Inventor： JAQUETTE GLEN ALAN , TAYEFEH MOROVAT
Abstract: A circuit for simultaneously detecting both MO and ROM signals reflected from an optical disk so that both signals are present and useable without switching from one to the other. The circuit eliminates switching time and switching transients. Two photodetectors are arranged to sense P and S components of polarized light in order to stimulate a differential amplifier and produce an output representative of MO recorded data. A second amplifier is connected to at least one of the photodetectors to produce an output representative of ROM recorded data and also representative of defects in the MO portion of the optical disk.
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