FOCUSING SOLENOID, ITS APPLICATION AND MANUFACTURING PROCESS

摘要

The present invention provides a focussing solenoid for focussing an electron beam in a picture taking tube. This focussing solenoid comprises a sleeve which has a helical etching in which are housed the turns of a first layer of wire. For all the other layers of wire wound in a helix about the sleeve, the slope of the turns of the helix with respect to the sleeve is substantially the same and the turns of one layer are guided by the turns of the preceding layer. Connections connect the layers together so that all the layers have the same winding direction about said sleeve.