Abstract: A method for controlling a particle acceleration energy in a radio-frequency quadrupole accelerator, the method being particularly adapted for ion implantation in the process of manufacturing semiconductor devices, wherein the particle acceleration energy is varied without the necessity of changing the resonant frequency of the RFQ accelerator so that the final energy of the particles has a plurality of distinct energy having a lower value than the designed voltage.

Abstract: A high-speed scan type X-ray generating apparatus for scanning X-ray generating positions along a circumference of an examinee, in which an electron beam is emitted from an electron gun into a ring-shaped vacuum tube. The electron beam is deflected by electromagnets or the like to run on a circular orbit through the vacuum tube. The electron beam is further deflected by different, small electromagnets to deviate from the circular orbit and impinge on a ring-shaped target, thereby generating an X-ray toward the center of the vacuum tube. By controlling the small electromagnets, the X-ray generating position is caused to scan at high speed along a circumferential wall of the ring-shaped target.

Abstract: In a multipole linear accelerator such as of a quadrupole type, fine positional adjustment of the tip portions of the electrodes constituting the multipole structure can be made with electric contact kept substantially unaffected between the electrodes and the cavity drum in which the electrodes are mounted. Each of the electrodes are provided with a series of contact plates on both sides of the root portion of the electrode over the whole length thereof. Each of the contact plates, which are held to the root portion of the electrode by means of an adjusting screw bolt, slantwise bridges the root portion of the electrode and the inner surface of the cavity drum with elastic contact pieces interposed.