Overvoltage protection device for capacitor externally connected to
power IC
    92.
    发明授权
    Overvoltage protection device for capacitor externally connected to power IC 失效
    电容器外部连接电容器的过电压保护装置

    公开(公告)号:US5555148A

    公开(公告)日:1996-09-10

    申请号:US357178

    申请日:1994-12-13

    CPC分类号: H02H9/046 H02H7/16

    摘要: When a charging voltage Vs of a charging capacitor C is judged to exceed a voltage Vth1 through a comparator 8 of a charging voltage monitoring circuit 2, a logical output of the comparator 8 becomes "High" so that a control circuit 3 permits a transistor 4 of a discharging circuit 1 to be conductive, whereby the capacitor C discharges. Through such discharging, the charging voltage Vs decreases. When the voltage Vs is then judged to be less than a voltage Vth2, the logical output of the comparator 8 becomes "Low" so that the control circuit 3 stops the operation of the discharging circuit 1, whereby a power IC 18 permits the capacitor C to charge again. The charging and the discharging operation of the capacitor C are repeatedly conducted in this manner that.

    摘要翻译: 通过充电电压监视电路2的比较器8判断充电电容器C的充电电压Vs超过电压Vth1时,比较器8的逻辑输出变为“高”,使得控制电路3允许晶体管4 的放电电路1导通,由此电容器C放电。 通过这样的放电,充电电压Vs降低。 然后当电压Vs被判断为小于电压Vth2时,比较器8的逻辑输出变为“低”,使得控制电路3停止放电电路1的操作,由此电源IC 18允许电容器C 再次收费。 以这种方式重复地进行电容器C的充电和放电操作。

    Phase shift device and laser apparatus utilizing the same
    93.
    发明授权
    Phase shift device and laser apparatus utilizing the same 失效
    相移装置和利用其的激光装置

    公开(公告)号:US5477554A

    公开(公告)日:1995-12-19

    申请号:US392689

    申请日:1995-02-23

    摘要: A phase shift device for a laser beam has a circular first area transparent so the laser beam and a second area provided around the first area and transparent to the laser beam. The first and second areas generate a phase difference for example 180.degree. in the passing light beams. The phase shift device is positioned for example at a beam waist of a laser scanning apparatus to form a beam spot of a diameter smaller than that defined by the numerical aperture of the imaging optical system. Structure of a laser apparatus employing such phase shift device is also disclosed.

    摘要翻译: 用于激光束的相移装置具有圆形的第一区域透明,因此激光束和设置在第一区域周围并对激光束透明的第二区域。 第一和第二区域在通过的光束中产生例如180°的相位差。 相移装置例如位于激光扫描装置的束腰处,以形成直径小于由成像光学系统的数值孔径限定的光束点。 还公开了采用这种相移装置的激光装置的结构。