Abstract: A method for determining a lay-up geometry for creating a component made of composite material, includes a body which is a volume of revolution of axis directed in an axial direction, the body extending around the axial direction in a circumferential direction, and a flange extending from one end of the body in a direction of extension, the method involving determining a first surface having the shape of the body that is to be produced and determining a second surface, situated in the prolongation of the first surface, the second surface having closed curves of undulation in the circumferential direction, wherein the second surface also has corrective curvatures in the direction of prolongation.

Abstract: The invention relates to a vacuum tube, particularly a cathode-ray visual-display tube. In order to absorb residual gases after having formed a vacuum in the tube a getter material (barium) is used, which is evaporated onto the internal walls of the tube from a getter support. According to the invention, instead of the getter support being welded to the electron gun it is independent of the gun and is fixed rigidly to the walls of the neck of the tube, in front of the electron gun. The distribution of the getter material in the tube is thus improved, especially for tubes focused by the neck, that is to say tubes for which the internal wall (covered with graphite) of the neck serves as a cylindrical electrode for focusing the electron beam, taken to the anode potential.