Patent ID: 7850432

Claim:
An ion pump comprising: a gastight housing defining a gas inlet, wherein the housing is configured for attachment to a vacuum chamber; an anode comprising a plurality of electrically-bonded, open tubes within the housing; a cathode comprising a first plate positioned on one side of the anode and spaced apart from the anode and a second plate positioned on an opposite side of the anode and spaced apart from the anode; one or more magnets for creating a magnetic field at the anode; a source for providing an electrical potential to the anode; and a blocking shield assembly within the housing between the cathode and the gas inlet configured to block particles generated at the cathode from direct line-of-sight transmission through the gas inlet, wherein the blocking shield assembly is further configured to block particles from transmission through the gas inlet that are generated at or reflected from surfaces within the housing that have line-of-sight to the cathode.