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公开(公告)号：EP0206824A2
公开(公告)日：1986-12-30
申请号：EP86304934
申请日：1986-06-25
Applicant: IBM
Inventor： LEWKOWICZ JULIAN
IPC: G11B11/00 , G11B7/00 , G11B7/0045 , G11B7/125 , G11B11/105 , G11B7/013 , G11B13/04
CPC classification number: G11B7/126 , G11B7/0045 , G11B11/10506 , G11B11/1053 , G11B11/10536
Abstract: An optical information-bearing-signal recorder employs thermally-induced recording of ablative, material movement, material phase change, magneto-optic or similar technologies. Synchronous noise in the recording is reduced by employing a heat-inducing energy pulse (25), coherent light for example, shaped to have an initial recording-initiating intensity amplitude (44, 44A) followed by a recording-sustaining amplitude (55, 55A). The duration of the recording-initiating amplitude portion is constant for all lengths of signals being recorded. When a rotating optical disk is employed as a record-bearing medium, the recording-initiating and recording-sustaining amplitudes are increased with increasing radius of the recording on the disk.
Abstract translation: 光信息承载信号记录仪采用烧蚀，材料移动，材料相变，磁光或类似技术的热感记录。 记录中的同步噪声通过采用导热能量脉冲（25）减少，相干光例如成形为具有初始记录起始强度幅度（44,44A），随后是记录维持幅度（55,55A ）。 记录起始振幅部分的持续时间对于正在记录的所有信号长度是恒定的。 当使用旋转光盘作为记录承载介质时，记录起始和记录维持幅度随着盘上记录的半径的增加而增加。
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公开(公告)号：JPS626443A
公开(公告)日：1987-01-13
申请号：JP8840486
申请日：1986-04-18
Applicant: IBM
Inventor： LEWKOWICZ JULIAN
IPC: G11B11/00 , G11B7/00 , G11B7/0045 , G11B7/125 , G11B11/105
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公开(公告)号：DE69016246D1
公开(公告)日：1995-03-09
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：DE69221049D1
公开(公告)日：1997-09-04
申请号：DE69221049
申请日：1992-09-04
Applicant: IBM
Inventor： CALL DAVID ERNEST , LEWKOWICZ JULIAN
IPC: G11B7/00 , G11B7/0045 , G11B7/0055 , G11B7/125 , G11B7/09 , H01S3/00
Abstract: Method and apparatus for calibrating the drive current circuit of a semiconductor laser diode subject to reflected optical feedback from a target surface such an an optical recording disk. The method makes use of two power output vs. drive current characteristic curves for the laser, one curve 190 for in-focus condition and the other curve 191 for out-of-focus condition, wherein the curves exhibit an asymptotic region at high power level (P2). Measurement of drive current I2 at power level P2 is taken under an out-of-focus condition. Measurement of drive current I1 and I3 at a predetermined low power level P1 are taken for both out-of-focus condition and in-focus condition. The linear slope of the in-focus curve 190 can thus be calculated to set desired power levels.
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公开(公告)号：DE68906047D1
公开(公告)日：1993-05-27
申请号：DE68906047
申请日：1989-02-07
Applicant: IBM
Inventor： DIMATTEO JOSEPH HOWARD , FIORINO BENJAMIN C , FENNEMA ALAN AUGUST , LEWKOWICZ JULIAN
Abstract: A focus acquire circuit for use in optical systems, such as optical data recorders and players, uses up to three parameter signals to indicate an in-focus condition. The zero crossing of a focus error signal is combined with a signal indicating that the focus error signal has approached a peak value and with a signal indicating a change in laser drive signal amplitude to indicate an in-focus condition. Various circuit details are illustrated showing how the three parameters can be combined together for indicating an in-focus condition.
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Patent Agency Ranking
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公开(公告)号：DE69106253T2
公开(公告)日：1995-06-29
申请号：DE69106253
申请日：1991-07-15
Applicant: IBM
Inventor： CALL DAVID ERNEST , LEWKOWICZ JULIAN
IPC: G11B7/00 , G11B7/004 , G11B7/0045 , G11B7/0055 , G11B7/125 , H01S5/06 , H01S5/062 , H01S5/0683 , H01S3/10 , G12B13/00 , H01S3/13
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公开(公告)号：DE68906047T2
公开(公告)日：1993-10-28
申请号：DE68906047
申请日：1989-02-07
Applicant: IBM
Inventor： DIMATTEO JOSEPH HOWARD , FIORINO BENJAMIN C , FENNEMA ALAN AUGUST , LEWKOWICZ JULIAN
Abstract: A focus acquire circuit for use in optical systems, such as optical data recorders and players, uses up to three parameter signals to indicate an in-focus condition. The zero crossing of a focus error signal is combined with a signal indicating that the focus error signal has approached a peak value and with a signal indicating a change in laser drive signal amplitude to indicate an in-focus condition. Various circuit details are illustrated showing how the three parameters can be combined together for indicating an in-focus condition.
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公开(公告)号：DE69128744D1
公开(公告)日：1998-02-26
申请号：DE69128744
申请日：1991-06-10
Applicant: IBM
Inventor： CARDERO SILVIO , GOODMAN BRIAN GERARD , LEWKOWICZ JULIAN
Abstract: The present invention relates to apparatus for detecting a digital data signal in the readback signal from a data recording system comprising means for receiving a readback signal (18) containing digital data signals, means for detecting transitions of the readback signal relative to the DC baseline of the readback signal, and means for utilising the transitions to generate the digital data signals (32). According to the invention the apparatus is characterised in it comprises threshold level generating means dependant on selected parameters of the readback signal for generating a varying threshold level (42) which defines the DC baseline.
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