Power efficient voltage to current coverter
    2.
    发明授权
    Power efficient voltage to current coverter 失效
    高效电压到电流覆盖器

    公开(公告)号:US5258653A

    公开(公告)日:1993-11-02

    申请号:US767713

    申请日:1991-09-30

    申请人: Stuart D. Perry

    发明人: Stuart D. Perry

    IPC分类号: G05F1/56 H03F1/02 H02J1/00

    摘要: A power efficient amplifier uses two stages, a low voltage stage and a high voltage stage. The low voltage stage supplies a nominal operating current to a load from a low voltage low power output when the requirements are small, and the high voltage stage supplies a desired output current to the load exceeding the nominal operating current when the load requires such. Switching to the high voltage output stage in response to sensing current to the load exceeding the nominal operating current conserves energy and increases operational efficiency. The amplifier circuitry produces a power efficient voltage-to-current transformation. The circuitry includes an operational amplifier that receives a signal proportional to the current flowing to the load and, an input signal which represents the desired load current. When the output increases above a certain level, it turns off the low voltage stage and turns on the high voltage stage causing the available output power to increase. A power efficient amplifier is obtained by operating with the lowest required output power.

    摘要翻译: 功率放大器使用两个阶段,即低压级和高压级。 当需求很小时,低电压级提供来自低压低功率输出的负载的额定工作电流,并且当负载需要时,高压级向期望的输出电流提供超过额定工作电流的负载。 响应于超过额定工作电流的负载的感测电流切换到高压输出级,节省能量并提高运行效率。 放大器电路产生功率有效的电压到电流转换。 电路包括运算放大器,其接收与流向负载的电流成比例的信号,以及表示所需负载电流的输入信号。 当输出增加到一定水平以上时,它会关闭低压级,并打开高压级,导致可用的输出功率增加。 通过以最低要求的输出功率运行,可获得功率高效的放大器。

    Magneto-optic read-out method and apparatus with polarization correction
means
    3.
    发明授权
    Magneto-optic read-out method and apparatus with polarization correction means 失效
    具有偏振校正装置的磁光读出方法和装置

    公开(公告)号:US4774615A

    公开(公告)日:1988-09-27

    申请号:US15753

    申请日:1987-02-17

    CPC分类号: G11B11/10515 G11B11/10545

    摘要: Disclosed herein are an improved method and apparatus for optically reading pre-recorded magnetic information on a magneto-optic recording element. The invention addresses the technical problem of minimizing the adverse effect of unpredictable variations in the state of polarization of the beam of radiation used for read-out. Such variations may be produced, for example, by birefringence variations in a transparent layer or substrate through which the recorded information is recovered. According to the invention, the undesired polarization variations are sensed from the system's output signal, and an error signal representative of such variations is produced. Such error signal is used to adjust the state of polarization of the read-out beam prior to detection by the system's detector elements. Preferably, the read beam is directed through the combination of a quarterwave plate and a Faraday rotator, and the error signal is used to control the magnetic field of the Faraday rotator. In effect, the combination of the quarterwave plate and Faraday rotator behaves like a variable phase retardation plate as far as the resultant output signal is measured by differential detection is concerned.

    Compensation apparatus for radial and vertical runout of an optical disc
    4.
    发明授权
    Compensation apparatus for radial and vertical runout of an optical disc 失效
    用于光盘的径向和垂直跳动的补偿装置

    公开(公告)号:US5742573A

    公开(公告)日:1998-04-21

    申请号:US642385

    申请日:1996-05-03

    IPC分类号: G11B7/095

    CPC分类号: G11B7/0956 G11B7/0953

    摘要: An apparatus for compensating for radial and vertical runout of an optical disc using an actuator having a lens for focus of a laser beam and wherein the focus and tracking currents control the position of the lens in the vertical and radial directions is disclosed. The apparatus focuses the actuator lens along at least one revolution of a track on an optical disc and producing lens position signals. Structures provided which responds to the lens position signals to produce the frequency content of surface height and track deviations of the optical disc using a frequency transform technique. The surface height and track deviations frequency content are stored and a signal representing the focusing and tracking actuator currents and in response to the focusing and tracking actuator current signals and the stored surface height and track deviation frequencies the lens position is controlled thereby reducing focusing and tracking errors.

    摘要翻译: 公开了一种用于使用具有用于激光束的焦点的透镜的致动器来补偿光盘的径向和垂直偏移的装置,并且其中聚焦和跟踪电流控制透镜在垂直和径向方向上的位置。 该装置将致动器透镜沿轨道的至少一圈旋转在光盘上并产生透镜位置信号。 提供的响应于透镜位置信号的结构使用频率变换技术产生表面高度的频率含量和光盘的偏离。 存储表面高度和轨道偏差频率含量,并且表示聚焦和跟踪致动器电流的信号,并且响应于聚焦和跟踪致动器电流信号以及存储的表面高度和轨道偏离频率,从而控制透镜位置,从而减少聚焦和跟踪 错误。

    Digital compensator for controlling a servo to correct the value of a
given parameter of a system
    5.
    发明授权
    Digital compensator for controlling a servo to correct the value of a given parameter of a system 失效
    数字补偿器,用于控制伺服以校正系统给定参数的值

    公开(公告)号:US5511052A

    公开(公告)日:1996-04-23

    申请号:US228918

    申请日:1994-04-18

    申请人: Stuart D. Perry

    发明人: Stuart D. Perry

    IPC分类号: G05D3/12 G11B7/09 G11B7/085

    摘要: A digital compensator controls a servomechanism, such as the focus servo of an optical disk drive. The compensator waits one full sample period before applying the correction that was calculated for the proceeding sample. The compensator does not use the present input sample in its calculation of the present output sample. The method for operating the digital compensator comprises the steps of receiving a first input sample at time t.sub.1, receiving a second input sample at time t.sub.2, and computing a first output in response to the first input sample at time t.sub.2. The method does not require a present input sample to calculate a present output.

    摘要翻译: 数字补偿器控制伺服机构,例如光盘驱动器的聚焦伺服。 补偿器在应用为进行样品计算的校正之前等待一个完整的采样周期。 在计算当前输出样本时,补偿器不使用当前输入样本。 用于操作数字补偿器的方法包括以下步骤:在时间t1接收第一输入样本,在时间t2接收第二输入样本,并在时间t2响应于第一输入样本计算第一输出。 该方法不需要当前输入样本来计算当前输出。

    Controlling the speed of an image-bearing member using relative states
    6.
    发明授权
    Controlling the speed of an image-bearing member using relative states 失效
    使用相对状态控制图像承载部件的速度

    公开(公告)号:US5325155A

    公开(公告)日:1994-06-28

    申请号:US58921

    申请日:1993-05-06

    申请人: Stuart D. Perry

    发明人: Stuart D. Perry

    IPC分类号: G03G15/00 H04N1/047 H04N1/12

    摘要: A method and apparatus for controlling the relative states between a rotating load member driven by a motor via a transmission where the velocity and position of the rotating load member are determined and the velocity and position of the motor are determined. The information concerning the velocity and position of the load and motor are used by a controller to generate a torque signal for controlling the velocity and position of the motor such that there is increased relative damping and relative stiffness between the rotating load member and the motor.

    摘要翻译: 一种用于控制由电动机驱动的旋转负载构件之间的相对状态的方法和装置,其经由传动装置确定旋转负载构件的速度和位置,并确定电动机的速度和位置。 控制器使用关于负载和电动机的速度和位置的信息来产生用于控制电动机的速度和位置的转矩信号,使得在旋转负载构件和电动机之间增加相对阻尼和相对刚度。

    Driving circuit for double solenoid focus actuator
    7.
    发明授权
    Driving circuit for double solenoid focus actuator 失效
    双电磁对焦执行器驱动电路

    公开(公告)号:US5070489A

    公开(公告)日:1991-12-03

    申请号:US387733

    申请日:1989-08-01

    IPC分类号: G11B7/09

    CPC分类号: G11B7/0927

    摘要: A circuit for driving a focus actuator of the "double-solenoid" (i.e. twin-coil) variety comprises circuit means for selectively supplying current to one or the other of the actuator's coils in such a manner as to eliminate any dead-band discontinuity in the actuator response while current-switching between the coils. Such circuitry comprises a current source and/or amplifier for selectively providing current to the actuator coils, means for detecting the difference in current flowing in the coils, an a differential amplifier, connected in a feedback loop, for comparing the output of the detecting means with a signal indicating the focal position of a focusing lens. The output of the differential amplifier is used to control the output of the current source, controlling which of the two actuator coils receives current and how much.

    摘要翻译: 用于驱动“双螺线管”(即双线圈)品种的聚焦致动器的电路包括用于以这样的方式选择性地向一个或另一个致动器线圈供应电流的电路装置,以消除任何死区 在线圈之间电流切换时的致动器响应。 这种电路包括用于选择性地向致动器线圈提供电流的电流源和/或放大器,用于检测在线圈中流动的电流差的装置,连接在反馈回路中的差分放大器,用于比较检测装置的输出 具有指示聚焦透镜的焦点位置的信号。 差分放大器的输出用于控制电流源的输出,控制两个致动器线圈中的哪一个接收电流以及多少。