Abstract: An image tube comprises a conductive film along the inside surface of an insulating tube extending axially of the image tube between a photoelectric cathode and a fluorescent anode. The conductive film should be electrically connected to the photoelectric cathode and have an axial length between 1/2 and 3/4 of that of the insulating tube. The conductive film may be formed along the outside surface of the insulating tube and either together with or without a conventional semi-insulating layer formed along the inside surface of the insulating tube.

Abstract: A target for an image pick-up tube employs a layer of lead monoxide P b O which exhibits substantially intrinsic conductivity. The surface region of the P b O layer is formed with a high energy level density effective to trap beam electrons landing thereon, while remaining in the intrinsically conductive state, by bombardment of the target surface with inert gas ions. Such a surface region effectively precludes injection of electrons into the target interior, and gives rise to improved resolution and dark current characteristics.