Guide system for electric charged particles - has electrodes under voltage supported on insulating rings in component holding metal tube

摘要

The guide system is formed by electron or ion sources, electron, or ion-optical devices etc. It has metal tube for holding the individual components of the system. Electrodes (4) under voltage are supported in the metal tube (1) via rings (2,3) of electrically insulating material. The component materials are chosen so that their thermal expansion coefficients are increased from inside outwards. Pref. the components under voltage are of a tungsten- copper alloy. The voltage carrying electrodes may be of vitreous carbon. The rings may be of aluminium oxide ceramic material. A spiral spring (7) is typically provided for securing the axial position of the support rings and the electrodes. The use of the metal tube offers a simple design for erection of systems with close tolerances, of self-centering type and with heating facilities.