Modulator switch with low voltage control

A cold cathode, crossed-field modulator switch, comprising:

• cathode electrode, source grid electrode, control grid electrode having relatively small apertures formed therein, and anode electrode disposed in spaced relation so as to form a cathode-electrode-to-source-grid gap, a source-grid-to-control-grid gap and a control-grid-to-anode electrode gap;
• means for maintaining gas under relatively low pressure in said inter-electrode gaps;
• means for producing a localized magnetic field which penetrates the cathode-to-source-grid gap but which magnetic field has no functionally significant penetration into the remaining inter-electrode gaps;
• means for applying a voltage to said source grid to create a potential difference between said cathode and source grid whereby an electric field is produced which extends at least across said cathode-to-source-grid gap, said magnetic field interacting with said electrical field in the gaseous environment in said cathode-to-source-grid gap to produce a plasma which is a source of electron and ion charge carriers;
• and
• modulator circuit means coupled to said control grid, said means adapted to selectively apply a positive potential to said control grid relative to the potential of said plasma to close said switch, and to apply a negative potential to said control grid relative to the plasma potential to interrupt current flow and thereby open the switch.

A cold cathode, crossed-field discharge switch, comprising:

• anode, cathode, source grid, and control grid electrodes;
• electrically insulating means supporting said electrodes in spaced relation, with said source grid adjacent said cathode electrode and said control grid adjacent said anode electrode, so as to provide a cathode-electrode-to-source grid gap, a source-grid-to-control-grid gap, and a control grid-to-anode-electrode gap;
• means for maintaining gas under a predetermined pressure in said gaps so that said gas can be ionized for electrical conduction;
• means for producing a localized magnetic field which penetrates the cathode-electrode-to-source grid gap;
• means for applying a voltage to said source grid to produce an electrostatic field to cause charge carrier generation, said magnetic field interacting with said electrostatic field in the gaseous environment in said inter-electrode gap between said source grid and said cathode electrode to produce a plasma which is a source of electron and ion charge carriers;
• and
• means for applying voltage to said control grid, said means being adapted to apply a voltage level at least equal to the plasma potential to close said switch device, said means being further adapted to apply negative potential relative to the plasma potential to interrupt conduction of such device.

An inductive energy storage circuit comprising:

• a current source;
• an inductive energy storage means coupled to said current source;
• a load;
• and
• switch means adapted to selectively couple said load to said inductive energy storage means by selectively opening and closing, said switch means comprising a cold-cathode plasma discharge switch comprising:
• (i) cathode, control grid and anode electrodes,
• (ii) means for providing a non-uniform plasma density distribution between said anode and said cathode electrodes, so that said plasma density is relatively high near the cathode and relatively low near the anode;
• and
• (iii) means for closing and opening said switch, said means comprising means for applying a positive potential relative to the potential of said plasma to said control grid to close said switch, and means for applying a negative potential relative to said plasma potential to said control electrode to open said switch.

A resistive load modulator circuit comprising:

• a voltage source;
• a resistive load;
• and
• modulator switch means adapted to selectively couple said load to said voltage source by selectively opening and closing, said switch means comprising a cold-cathode, plasma discharge switch comprising:
• (i) cathode, control grid and anode electrodes;
• (ii) means for providing a non-uniform plasma density distribution between said anode and said cathode electrodes, so that said plasma density is relatively high near the cathode and relatively low near the anode;
• and
• (iii) means for closing and opening said switch, said means comprising means for applying a positive potential relative to the potential of said plasma to said control grid to close said switch, and means for applying a negative potential relative to said plasma potential to said control grid to open said switch.