ELECTRIC CHARGE CONVERSION TYPE SEALED NEUTRON GENERATING TUBE

PROBLEM TO BE SOLVED: To provide a compact sealed neutron generating tube for well logging resisting an impact at a high temperature by preventing a dielectric breakdown reducing the life of the neutron tube caused by an electric discharge in the presence of a too strong electric field. SOLUTION: This neutron tube is structured such that an electric charge conversion electrode 11 is placed on the downstream of a negative ion source 4 in an air tight vacuum container 2 filled with gaseous deuterium and gaseous tritium at a low pressure, and a target 5 is placed on the downstream of the electric charge conversion electrode 11. Energy of ion discharge from the negative ion source by impressing a positive voltage on the electric charge conversion electrode 11 is converted into positive ion when passing through the electric charge conversion electrode 11. The positive ion is still accelerated to the target maintained at a ground potential, resulting in obtaining energy accelerated by a voltage twice as high as that impressed on the electric charge conversion electrode 11.