METHOD AND APPARATUS FOR GENERATION OF A UNIFORM-PROFILE PARTICLE BEAM

摘要

The present invention pertains to an apparatus for generating a charged particle beam comprising a magnetic element for controlling the profile of the beam in a predetermined plane. A cathode can be provided for emitting charged particles and an anode for accelerating the charged particles along an axis of travel. The present invention also pertains to a method for generating a particle beam that has a uniform profile in a predetermined plane comprising inducing emission of charged particles from an emitter, accelerating those particles along and toward an axis of beam travel, generating a magnetic field with a component aligned with the axis of beam travel but different in the predetermined plane than at the emitter, and modifying the beam profile.

主权项

1. An apparatus for generating a charged particle beam comprising:
a cathode for emitting charged particles; an anode configured to accelerate said charged particles along an axis of travel of said charged particle beam; and a first magnetic element configured to control a beam profile of said charged particle beam in a predetermined plane by changing the strength of a component of a magnetic field along said axis of travel; wherein said charged particles are emitted toward a planar target screen having a planar surface, wherein a second magnetic element is positioned adjacent to and around the perimeter of said target screen, wherein a plane coincident with said planar surface of said target screen and extending outside said perimeter of said planar surface of said target screen would pass through said second magnetic element.