An apparatus used to control a workpiece inside a vacuum chamber. The workpiece is supported on a workpiece holder in the vacuum chamber. The workpiece is isolated from the atmosphere outside of the vacuum chamber by differentially pumped vacuum seals and an integral air bearing support. The differentially...http://www.google.de/patents/US5898179?utm_source=gb-gplus-sharePatent US5898179 - Method and apparatus for controlling a workpiece in a vacuum chamber
