The combined linear and rotational feedthrough is useful for positioning of targets or aperture slits in a particle accelerator beam. This feedthrough is especially designed for use with a continuous variable beam attenuator, as is often required, for example, during particle-beam measurements on semiconductor targets. Please note (as viewed in above picture) that the grid can be rotated and thus provides for a continuously variable attenuation of the beam.


A shaft can be displaced by 3.15 inches between the two fixed positions and also be rotated 360°. Sealing of moving parts is accomplished be means of membrane bellow and a magnetic fluid joint. The unit fits a standard diagnostic chamber and the stroke is matched to the chamber dimension.