CORSOD HEATER ASSEMBLY FOR ELECTRON BEAM DEVICE

摘要

PURPOSE: To enhance reliability of fixing and easily replace an emitter by using a split ring to be fixed to a heater as means for fixing a mask and the emitter to a main body. CONSTITUTION: A ring-like groove 3 is formed at the end of an inside surface of a cup of a body 1 for containing a graphite heater 2 therein. An emitter 4 and a graphite mask 5 are mounted on the heater 2 in sequence coaxially. The mask 5 and the emitter 4 are fixed via a split graphite ring 6 having a conical side face. The split ring 6 is fitted to the side face of the mask 5 with a gap 'a'. The groove 3, into which the emitter 4 and the split ring 6 are contained, has two portions in conformity with the side face of the emitter 4 and the conical side face of the split ring 6. Consequently, it is possible to secure high reliability of fixing of the mask 5 and the emitter 4 and simplify replacement of the emitter 4.