| 摘要 |
<p>PURPOSE:To obtain good emission life characteristic through preventing unnecessary thermal evaporation of electron radiating material from the faces except the electron radiating face of a cathode body by fixing wax material to the cathode body by means of laser weld after temporarily sintering it to the cathode body in the reducing atmosphere. CONSTITUTION:The wax material molten in trichlene is applied to the side face of a cathode body 1 by using a writing brush. Subsequently, temporary sintering of the wax material is finished by heating it to the temperature, 1,200 deg.C in the reducing atmosphere. Subsequently, a laser beam is radiated to the side face and back face of the cathoide body 1 the times respectively, a wax material film 11 is formed by fixing the wax material to the cathode body 1 and therefore, the impregnated cathode 20 is formed. Thereby, the thermal evaporation of the impregnated cathode 20 is caused from only the front of the cathode body 1 when the cathode is operated, resultautly the thermal evaporation amount of the electron radiating material can be reduced to about one third of the normal level.</p> |
