Radial geometry electron beam controlled switch utilizing wire-ion-plasma electron source

A switch system controlled by an electron beam and employing a radial geometry, comprising:

• a hollow outer switch electrode member;
• an inner switch electrode member disposed within said outer electrode member;
• gas envelope means for enveloping said inner and outer electrode members and adapted to contain an ionizable switch gas within an annular switch cavity region disposed between said switch electrodes, wherein conduction between said switch electrodes is supported when said switch gas is ionized to form a conductive plasma, and said switch electrodes are electrically isolated from each other when said gas is not ionized;
• means for introducing a beam of high energy electrons into said switch cavity region to ionize said switch gas and form said plasma;
• and
• means for turning said electron beam on and off by application of a relatively low potential and thereby respectively ionizing the switch gs to close the switch when the beam is turned on and allowing the plasma to decay to open the switch when the beam is turned off.

An electron-beam-controlled switch employing a radial geometry with an electron gun to provide the controlling electron beam, comprising:

• an electron gun cathode comprising a substantially cylindrical inner structure having an electron emissive surface;
• an electron gun anode comprising a substantially cylindrical outer grid structure, said cylindrical structure of said cathode being disposed within said outer cylindrical structure of said anode;
• means for defining a first gas envelope about said anode and cathode for containing an electron gun ionization gas, said envelope means comprising a substantially cylindrical foil support structure carrying electron transmissive foil windows comprising a first switch electrode, said foil structure and said cylindrical grid structure arranged to define a substantially annular electron gun ionization chamber;
• an array of wire anodes disposed within said electron gun ionization chamber;
• means for selectively applying a relatively low ionization potential to said wire anodes for selectively ionizing said electron gun gas to produce a plasma containing positive ions;
• means for applying a large negative potential to said electron gun cathode for extracting positive ions from said chamber to bombard said cathode, thereby generating secondary electrons which are repelled radially outwardly by said large potential through said foil windows;
• a second switch electrode comprising an outer cylindrical structure disposed outside of said first switch electrode;
• and
• means for defining a substantially annular switch ionization chamber between said first and second switch electrodes, said chamber adapted to contain a switch ionization gas, whereby said switch gas is selectively ionized by said secondary electrons to provide a conductive plasma coupling the first and second switch electrodes when the ionization potential is applied to said wire anodes, and said plasma quickly decays when the ionization potential is turned off, so that conduction between the switch electrodes is no longer supported.