| abstract |
An ion beam apparatus comprises a source of ions (1), an evacuatable chamber (11), first and second electrodes (3,5) disposed within the chamber for forming an ion beam from ions from the ion source, the first electrode being electrically insulated from the second electrode. First and second supports for (17,19) supporting said first and second electrodes, respectively, are provided. The apparatus is arranged to allow said electrodes to be moved independently of one another relative to said chamber from outside said chamber. <IMAGE> |