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1.发明授权Acquiring focus in optical systems using a focus error signal and a laser drive signal 失效使用聚焦误差信号和激光驱动信号获得光学系统中的焦点
公开(公告)号：US4998233A
公开(公告)日：1991-03-05
申请号：US155390
申请日：1988-02-12
CPC分类号： G11B7/08511 , G11B7/0908
摘要： A focus acquire circuit for use in optical systems, such as optical data recorders and players, uses up to three parameters 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 cna be combined together for indicating an in-focus condition.
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公开(公告)号：US4731773A
公开(公告)日：1988-03-15
申请号：US857268
申请日：1986-04-30
申请人： Julian Lewkowicz
发明人： Julian Lewkowicz
IPC分类号： G11B11/00 , G11B7/00 , G11B7/0045 , G11B7/125 , G11B11/105 , H04N5/76
CPC分类号： G11B7/126 , G11B11/10506 , G11B11/1053 , G11B11/10536 , G11B7/0045
摘要： 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, coherent light for example, shaped to have an initial recording-initiating intensity amplitude followed by a recording-sustaining amplitude. 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.
摘要翻译： 光学信息载体信号记录仪采用消融，材料移动，材料相变，磁光或类似技术的热致记录。 记录中的同步噪声通过使用导热能量脉冲（例如相干光）而被降低，相干光被成形为具有初始记录起始强度幅度，随后是记录维持幅度。 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：US06975467B1
公开(公告)日：2005-12-13
申请号：US09976669
申请日：2001-10-11
申请人： Julian Lewkowicz , Larry J. Koudele
发明人： Julian Lewkowicz , Larry J. Koudele
IPC分类号： G11B27/36
CPC分类号： G11B5/6029 , G11B5/09 , G11B5/5534 , G11B5/6005 , G11B2220/2516
摘要： A method and apparatus for detecting a high fly write condition in a disk drive is disclosed. Amplitudes of automatic gain control (AGC) fields are used in connection with determining whether a high fly write condition exists in a disk drive, since the amplitude of an AGC field read by a head is generally related to the flying height of the head. In one embodiment, a calibration process is performed to obtain average amplitudes of AGC fields on a zone-by-zone basis for a head associated with a disk surface. These average amplitudes of AGC fields are then stored onto the disk surface for later use. When a write operation is to be performed, the head measures the amplitude of the AGC field associated with a data sector onto which a block of data is to be stored. The measured amplitude of the AGC field is compared to the average amplitude of the AGC fields for the zone associated with the AGC field being read. If the difference between the measured amplitude of the AGC field and the average amplitude for the AGC fields for the zone is outside of a certain tolerance, a high fly write condition may exist. Accordingly, data written during a high fly write condition may be rewritten when the flying height has returned to normal or some other remedial action may be taken.
摘要翻译： 公开了一种用于检测磁盘驱动器中的高飞写入状态的方法和装置。 自动增益控制（AGC）场的幅度用于确定磁盘驱动器中是否存在高飞写条件，因为头读取的AGC场的幅度通常与头的飞行高度相关。 在一个实施例中，执行校准处理以获得与磁盘表面相关联的磁头的逐个区域的AGC场的平均振幅。 然后将AGC场的这些平均振幅存储在磁盘表面上供以后使用。 当要执行写入操作时，头部测量与要存储数据块的数据扇区相关联的AGC字段的幅度。 将AGC场的测量幅度与被读取的AGC场相关联的区域的AGC场的平均幅度进行比较。 如果AGC场的测量幅度与该区域的AGC场的平均幅度之间的差异超出了一定的公差，则可能存在高飞写入条件。 因此，当飞行高度恢复正常或可采取一些其他补救动作时，可以在高飞写入状态期间写入的数据被重写。
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4.发明授权Laser power calibration by measuring laser drive current at out of focus and in focus conditions 失效通过在焦点和焦点条件下测量激光驱动电流进行激光功率校准
公开(公告)号：US5216659A
公开(公告)日：1993-06-01
申请号：US757748
申请日：1991-09-11
申请人： David E. Call , Julian Lewkowicz
发明人： David E. Call , Julian Lewkowicz
IPC分类号： G11B7/00 , G11B7/0045 , G11B7/0055 , G11B7/125
CPC分类号： G11B7/126
摘要： Apparatus and method 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 for in focus condition and one for out of focus condition, wherein the curves exhibit an asymptotic region at high power levels (P.sub.2). Measurement of drive current (I.sub.2) power level P.sub.2 is taken under an out of focus condition. Measurements of drive current at a predetermined low power level P.sub.1 are taken for both (I.sub.1) and in focus condition (I.sub.3). The linear slope of the in focus curve can thus be calculated to set desired power levels.
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公开(公告)号：US5070495A
公开(公告)日：1991-12-03
申请号：US336479
申请日：1989-04-12
IPC分类号： G11B11/10 , G11B7/00 , G11B7/0045 , G11B7/125 , G11B11/105 , G11B27/36
CPC分类号： G11B7/126 , G11B11/10506 , G11B11/10595 , G11B27/36
摘要： 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：US4191977A
公开(公告)日：1980-03-04
申请号：US947308
申请日：1978-09-29
申请人： Julian Lewkowicz
发明人： Julian Lewkowicz
摘要： An electromagnetic transducer particularly of the magneto-resistive (MR) type is biased by an inductive circuit means and operates within the linear portion of its characteristic curve. The inductive circuit means is interconnected to the output terminals of said transducer. An amplifier means is connected to the output terminals of the transducer and the inductive circuit means. The amplifier means is also biased by the inductive circuit means. The biasing scheme is enhanced when a gyrator is used as the inductive circuit means.
摘要翻译： 特别是磁阻（MR）型的电磁换能器由感应电路装置偏置并在其特性曲线的线性部分内工作。 感应电路装置互连到所述换能器的输出端。 放大器装置连接到换能器和感应电路装置的输出端。 放大器装置也被感应电路装置偏置。 当使用回转器作为感应电路装置时，偏置方案得到增强。
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公开(公告)号：US4075671A
公开(公告)日：1978-02-21
申请号：US744839
申请日：1976-11-24
IPC分类号： G01D5/18 , G01H11/02 , G11B5/00 , G11B5/02 , G11B5/39 , G11B19/02 , G11B23/00 , H03G3/20 , G11B5/30
CPC分类号： H03G3/3005 , G11B23/0007 , G11B5/39 , G11B19/02 , G11B2005/0018
摘要： Two magnetoresistive (MR) elements are connected with two matched impedance elements in a bridge arrangement for sensing magnetic flux manifesting information recorded on magnetic media. An alternating current (AC) bias is applied to the bridge's input, and short-term variations in the bridge output signal envelope are detected as representing recorded information. Long-term (average) variations in the signal envelope are also detected and used to adjust the AC bias to maintain a constant average envelope. Additional bridge inputs may be connected in parallel with the first, and the additional bridges' outputs used to derive additional information signals without any additional AC bias adjustment circuits.
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8.发明授权Method and apparatus for high fly write detection using stored amplitude values 失效使用存储的振幅值进行高速写入检测的方法和装置公开(公告)号：US06987628B1
公开(公告)日：2006-01-17
申请号：US09905604
申请日：2001-07-13
IPC分类号： G11B27/36
CPC分类号： G11B27/36 , G11B5/6029
摘要： A method and apparatus for detecting a high flying condition of a transducer head in a computer disk drive is provided. The method and apparatus allow the detection of high fly write events that occur over one or a small number of data sectors. In addition, the present invention provides a method and apparatus for detecting high fly write events with a great deal of sensitivity. The method and apparatus of the present invention provide quick response and high sensitivity by monitoring the strength of a signal derived from data written to the disk, and signaling a high fly write event if the monitored signal strength in connection with a particular piece of data is less than a stored high fly write number corresponding to that piece of data by a predetermined amount.
摘要翻译： 提供一种用于检测计算机磁盘驱动器中的换能器头的高飞行状态的方法和装置。 该方法和装置允许检测在一个或少量数据扇区上发生的高飞写入事件。 另外，本发明提供了用于以高灵敏度检测高飞写入事件的方法和装置。 本发明的方法和装置通过监视从写入盘的数据得到的信号的强度来提供快速响应和高灵敏度，并且如果与特定数据片相关的监视信号强度为 小于与该数据片相对应的预定量的存储的高速写入号码。
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公开(公告)号：US06678102B1
公开(公告)日：2004-01-13
申请号：US09649660
申请日：2000-08-29
申请人： Bruce Liikanen , Julian Lewkowicz , Larry Koudele
发明人： Bruce Liikanen , Julian Lewkowicz , Larry Koudele
IPC分类号： G11B2736
CPC分类号： G11B27/36 , G11B5/6029 , G11B20/10027 , G11B20/1816 , G11B2020/1281 , G11B2220/2516
摘要： A method and apparatus for detecting a high fly write event in a computer disk drive is provided. The method and apparatus allow the detection of high fly write events occurring over very short time spans. In addition, the present invention provides a method and apparatus for detecting high fly write events with a great deal of sensitivity. The method and apparatus of the present invention provide quick response and high sensitivity by monitoring the strength of a signal derived from a servo sector position burst or a group of bursts, and signaling a high fly write event if the monitored signal strength is less than a predetermined or threshold amount.
摘要翻译： 提供了一种用于检测计算机磁盘驱动器中的高飞写入事件的方法和装置。 该方法和装置允许检测在非常短的时间跨度上发生的高飞写入事件。 另外，本发明提供了用于以高灵敏度检测高飞写入事件的方法和装置。 本发明的方法和装置通过监视从伺服扇区位置脉冲串或一组脉冲串导出的信号的强度来提供快速响应和高灵敏度，并且如果所监视的信号强度小于 预定或阈值。
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公开(公告)号：US5309461A
公开(公告)日：1994-05-03
申请号：US921894
申请日：1992-07-29
IPC分类号： G11B7/00 , G11B7/0045 , G11B7/125 , H01S5/068 , H01S5/0683 , H01S3/00
CPC分类号： G11B7/126 , H01S5/06825 , H01S5/06832
摘要： A drive circuit for a laser which has the capability of eliminating transient conditions when switching a high frequency modulator on or off, and including elements for maintaining desired depth of modulation. These capabilities are included in a circuit that automatically compensates for changing conditions due to temperature, laser characteristics and fluctuations in media reflectivity.
摘要翻译： 一种用于激光器的驱动电路，其具有在开启或关闭高频调制器时消除瞬态条件的能力，并且包括用于维持所需调制深度的元件。 这些功能包括在电路中，自动补偿由于温度，激光特性和介质反射率波动引起的变化条件。
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