Abstract: An electron collector is shown having four axisymmetric electrodes with off-axis apertures therein which receive an electron beam. The application of a consecutively smaller voltage to each electrode as compared to the cathode that generates the electron beam creates an electrostatic field that efficiently deflects the beam electrons onto the electrodes for their collection.

Abstract: An improved electron gun is shown with a cathode having a smooth, concaved surface and a grooved pattern therein which matches, and is aligned with, the pattern of a shadow grid placed immediately before the cathode surface so that the outer, larger radius of curvature of the shadow grid closest to the cathode is substantially identical and concentric with the radius of curvature of the smooth, concave cathode surface. Beyond the shadow grid is a control grid which controls the flow of electrons emitted from the cathode toward an anode. The grooves which form the pattern within the cathode surface have tapered side walls and rounded outer and inner corners to improve the flow of emitted electrons and facilitate manufacture.