Electrode, particularly sole electrode for m-type electron tube

Claim 1

IN AN ELECTRON TUBE HAVING A SOURCE OF PRIMARY ELECTRONS AND PROVIDED WITH AN ELECTRODE STRUCTURE DELIMITING AN INTERACTION SPACE, MEANS FOR GUIDING SAID ELECTRONS IN A FIRST DIRECTION PAST SAID ELECTRODE STRUCTURE INCLUDING MEANS FOR GENERATING WITHIN SAID INTERACTION SPACE AN ELECTRIC FIELD AND A MAGNETIC FIELD CROSSED WITH SAID ELECTRIC FIELD THEREBY GUIDING SAID ELECTRONS PERPENDICULARLY TO BOTH OF SAID FIELD, THE IMPROVEMENT ESSENTIALLY CONSISTING OF SECOND MEANS FOR SUBSTANTIALLY PREVENTING THE ESCAPE OF SECONDARY ELECTRONS FROM SAD ELECTRODE STRUCTURE DUE TO THE IMPACT THEREAGAINST OF SAID PRIMARY ELECTRONS, SAID SECOND MEANS INCLUDING BI-DIMENSIONAL NETWORK MEANS EXTENDING IN TWO DISTINCT DIRECTIONS AND EFFECTIVELY CONSTITUTING SECONDARY ELECTRONS TRAPS AND OPERABLE TO LEAVE SUBSTANTIALLY UNAFFECTED THE NON-RETARDING CHARACTERISTIC OF SAID ELECTRODE STRUCTURE AT THE UTILIZED FREQUENCIES.