Abstract: The target of a television camera tube comprises photoconductive material in the form of a regularly interrupted structure so that both the photoconductive material and parts of the signal electrode are accessible to the electron beam. The potential difference between the signal electrode and the cathode is adjusted so that during scanning, the signal electrode accepts a proportion of the beam current dependent on the local potential of the photoconductor surface, and the photoconductor is stabilized only during fly-back. The camera tube thus has an adjustable inherent amplification without increased inertia.

Abstract: In a method of manufacturing an electric discharge tube in which at least one of the components of the tube is subjected to a treatment in a vessel sealed from the atmosphere. The vessel consists of at least two parts which are sealed against each other with the interposition of a gallium-containing material in the liquid state. One of the parts of the vessel preferably forms a part of the final envelope of the discharge tube.

Abstract: A television camera tube having a discrete structure of photosensitive elements provided on an electrically conductive carrier covered entirely with photoconductive material or another resistance material, so that with a suitable potential applied to the carrier a potential distribution occurs having successive saddle points for the scanning beam. Variation and exposure of the discrete photoconductive elements then results in a variation in beam splitting in the saddle points, as a result of which the tube has a greater or smaller extent of natural amplification.The invention relates to a television camera tube having a target which is to be scanned by an electron beam and which comprises a transparent electrically conductive signal electrode and discrete structure of photosensitive elements provided on an electrically conductive carrier.Such a camera tube is known from the U.S. Pat. No.