Patent ID: 6621372
Filing Date: 2003-09-16
Classification: H01J,H03H

Abstract:
An impedance matching device, comprising at least two stubs provided serially on a main coaxial tube to be separated from each other with a predetermined interval in a tube axial direction, said main coaxial tube having an inner conductor and an outer conductor,wherein said each stub comprising: a variable capacity capacitor whose one end is to be jointed to said inner conductor of said main coaxial tube, said variable capacity capacitor having a movable side electrode and a fixed side electrode; an electrically conductive capacitor cover to be jointed to said outer conductor of said main coaxial tube so as to be electrically joined to the other end of said variable capacity capacitor as well as to cover a surrounding of said variable capacity capacitor; and a drive motor arranged on an outside of said capacitor cover so as to drive said movable side electrode of said variable capacity capacitor.