A sweep scheme which may be used with an ion‐beam laser is investigated. In this scheme, a beam of ions passes through a symmetric electric‐quadrupole triplet lens and into a parallel‐plate transmission line. A voltage pulse of finite duration (TEM‐mode) propagates along the transmission line in the downstream direction with the velocity of light. The ions pass out the end of the transmission line where they are space‐charge neutralized and are incident on a target parallel to the transmission‐line axis. We show that the point of intersection of the beam with the target moves along the target with the velocity of light due to the voltage pulse. For the beam to remain focused as it hits the target, the focusing potential of the lens must be varied, and we determine the required time variation using the thin‐lens approximation. A set of operating parameters is given.
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