Electron guides with extraction, a potentially useful new class of electron devices

We at RCA have been exploring the possibility of constructing low voltage electrostatic periodic focusing structures for electrons which allow beam extraction at any period. These are the analogs to optical light pipes, where it should be noted that electrons can be deflected out of a guide relatively easily compared to deflecting light out of an optical fiber. Such devices can form the basis of a new class of cathodoluminescent displays. This paper will review the structures which have been proposed in the past primarily for traveling wave tubes and how they can be modified for beam extraction. The evolution of a beam of particles will be discussed using non-linear phase space transformations which conserve phase space volume. Finally some qualitative features of the spot profiles of extracted beams will be explained.