Electron tube with collector having magnetic field associated therewith, said field causing electron dispersion throughout the collector

Claim 1

AN ELECTRON TUBE APPARATUS COMPRISING, AN ELECTRON GUN FOR PROJECTING OVER AN ELONGATED BEAM PATH A BEAM OF ELECTRONS HAVING AN AVERAGE BEAM POWER GREATER THAN 100 KILOWATTS, A COLLECTOR ASSEMBLY SPACED FROM SAID GUN AT THE TERMINAL END OF THE BEAM AND DISPOSED TO COLLECT SAID BEAM, AN INTERACTION STRUCTURE FOR SUPPORTING ELECTROMAGNETIC ENERGY AND SO DISPOSED THAT THE ELECTROMAGNETIC FIELDS OF SAID INTERACTION STRUCTURE INTERACT WITH SAID BEAM, FIRST MEANS FOR GENERATING A BEAM-FOCUSING MAGNETIC FIELD FOR MAINTAINING SAID BEAM IN FOCUS AS IT PASSES THROUGH SAID INTERACTION STRUCTURE, SAID BEAMFOCUSING MEANS INCLUDING A PAIR OF APERTURED POLE PIECES AXIALLY SPACED APART ALONG THE BEAM PATH AND STRADDLING SAID INTERACTION STRUCTURE FOR MAINTAINING THE BEAM-FOCUSING MAGNETIC FIELD WITHIN THE BEAM PATH, ONE OF AID POLE PIECES BEING DISPOSED BETWEEN THE TERMINAL END OF SAID INTERACTION STRUCTURE AND SAID COLLECTOR ASSEMBLY AND BEING ADAPTED TO SHIELD SAID COLLECTOR ASSEMBLY FROM THE BEAM-FOCUSING MAGNETIC FIELD BUT NEVERTHELESS PERMITTING A LEAKAGE MAGNETIC FIELD TO PERMEATE SAID COLLECTOR REGION, AND A SECOND MAGNETIC FIELD-GENERATING MEANS ARRANGED TO PRODUCE A STATIC DISPERSING MAGNETIC FIELD IN THE REGION OF SAID COLLECTOR ASSEMBLY WHICH DISPERSING FIELD IS SUPERIMPOSED UPON SAID LEAKAGE FIELD IN SAID COLLECTOR ASSEMBLY, SAID SECOND MAGNETIC FIELD-GENERATING MEANS BEING SUCH THAT THE RESULTANT MAGNETIC FIELD RESULTING FROM SAID SUPERIMPOSITION HAS OVER A SUBSTANTIAL PART OF THE LENGTH OF THE COLLECTOR ASSEMBLY IN THE DIRECTION OF THE AXIS OF SAID BEAM PATH A SUBSTANTIAL RADIAL COMPONENT FOR DISPERSING THE BEAM.