Patent Number: 
Section: claims

1. A neutron generator including an electrical ground connected to a neutron generating target, said neutron generator comprising:a plasma chamber disposed in a plasma ion source, and an external RF antenna disposed outside and around said plasma chamber;an extraction and acceleration system including three electrodes, a first electrode having a centered aperture being disposed at an end of said plasma chamber for extracting an ion beam, a second electrode having a centered aperture being disposed a distance from said first electrode that is between said first electrode and a neutron generating target positioned outside plasma chamber, and a third electrode having a centered aperture being disposed a distance from the second electrode that is between said second electrode and said neutron generating target, all three apertures aligned for extracting the ion beam, the ion beam being a deuterium ion beam, from the plasma chamber;said neutron generating target electrically connected to ground, said neutron generating target including a tapered conical concave surface having an apex, the concave surface having a target surface area into which ions in the ion beam impact, the concave target surface area being shaped and disposed so that the ions impact the target surface area at angles from normal to the target surface area that are greater than zero degrees, and said neutron generating target disposed outside and away from said plasma chamber and positioned so that the extracted ion beam is incident thereon to load the target and generate neutrons by reactions. 2. The neutron generator of claim 1 wherein the acceleration system accelerates the ions to an energy of the order of about 100 keV. 3. The neutron generator of claim 1 wherein the plasma ion source chamber is made of quartz or ceramic. 4. The neutron generator of claim 1 wherein the target is separated from the ion source by a drift tube. 5. The neutron generator of claim 4 wherein the ion source has a diameter of about 2 cm or less and a length of about 2.5 cm or less, and the drift tube has a diameter of about 5 mm or less and a length on the order of about 10 cm. 6. The neutron generator of claim 4 wherein the drift tube has a cooling channel. 7. The neutron generator of claim 1 further comprising an RF generator and a matching network through which the RF antenna is connected to the RF generator. 8. The neutron generator of claim 1 further comprising a plasma confinement solenoid surrounding the RF antenna.