The Design of Electrostatic Zoom Image Intensifies

Abstract

Publisher Summary This chapter discusses the design of electrostatic-zoom image intensifiers. Electrostatic image-intensifier design is an excellent subject for the application of large computers. A zoom tube can be produced by introducing into the triode a fourth electrode either in the anode space or in the cathode space. Anode-space zooming is most simply achieved by separating the screen from the anode. The essential feature of such a tube is that it comprises two independent parts, the cathode lens and the zoom lens, separated by a field-free space within the anode. This separation simplifies the design problem considerably because the basic properties of the two parts can be computed separately, and the results of combining them in any manner are then calculable by the simple formulae of Gaussian optics. These principles provide guidelines that help to optimize the tube performance overall, but much still depends on the location and detailed shaping of the electrodes. A trial-and-error study of these effects can be economically conducted by computation.