Abstract: An improved electron beam deflector with incorporated permanent magnets for picture correction, where the magnets and the magnetic field generated by these magnets are surrounded by an auxiliary magnetic shielding that forms one piece with the deflector and is positioned with high geometrical precision with respect to the magnets. This auxiliary shielding causes the picture correction efficiency to be unaffected by the shape and geometry of positioning of the metal elements in the vicinity of the deflector when it is being assembled and during its operation. The deflector can be used with picture tube devices, particularly of the cathode-ray type.

Abstract: Disclosed is an electron gun for cathode ray tubes successively comprising an electron source electrode or cathode, a control or Wehnelt electrode, a first acceleration electrode or anode carried to an adjustable voltage and at least one focusing or second acceleration electrode in which there is inserted, between the first acceleration electrode and the focusing or second acceleration electrode, an additional electrode which is carried, during operation, to a fixed biase voltage, this electrode forming a low-powered electrostatic lens with the anode electrode and forming a high-powered electrostatic lens with the second acceleration electrode.

Abstract: An electron gun comprising in succession in a vacuum envelope an electron source electrode or cathode, a control grid electrode, a first accelerating electrode or anode and a first and second focussing electrode. It further comprises connections for subjecting in operation each electrode to a polarizing voltage. The first focussing electrode is raised in operation to a polarizing voltage several tens of times higher than the polarizing voltage of the anode which precedes it and the second focussing electrode is raised in operation to a polarizing voltage several times higher than the polarizing voltage of the first focussing electrode which precedes it. The first focussing electrode and the anode form thus a prefocussing lens while the second focussing electrode and the first focussing electrode form a main lens.