LASER HOT CATHODE STRUCTURE

摘要

PURPOSE:To sharply improve the quantum efficiency of a cathode structure of an electron gun or the like via a simple modification. CONSTITUTION:A cathode electrode section 1 is provided in an electron gun, a laser beam is radiated to a cathode 2 provided in it and wound with a heating coil 3, and the generated electron beam is emitted through the small hole of an anode electrode section 4 and accelerated by a cavity 7. When the laser beam is radiated while the cathode 2 is heated at a prescribed temperature, the quantum efficiency is sharply improved.