Interlocking periodic permanent magnet assembly for electron tubes and method of making same

摘要

The present invention is a periodic permanent magnet (PPM) assembly used to produce a focussing field within an electron tube, and the corresponding method of manufacturing the same. The present invention PPM includes producing two opposing semi-cylindrical stacks by alternately stacking semi-annular shaped magnets and pole pieces. Once the two semi-cylindrical stacks are formed, they are joined around the electron tube, such that the various pole pieces and magnets of the two semi-cylindrical stacks align. As a result of the joining of the two semi-cylindrical stacks, a cylindrical periodic permanent magnet assembly is formed around the electron tube in a cost effective and labor efficient manner.